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251.
128:49617
Some kinetic aspects of lignin reactions in chlorine dioxide bleaching.
Ljunggren, Sten; Gunnarsson, Per-Ivar (STFI, Stockholm S-114 86,
Swed.). Int. Symp. Wood. Pulping Chem., 8th, Volume 2, 303-308.
Gummerus Kirjapaino Oy: Jyvaskyla, Finland. (English) 1995. CODEN:
65KDAY. DOCUMENT TYPE: Conference CA Section: 43 (Cellulose,
Lignin, Paper, and Other Wood Products)
Much effort has recently been made to clarify the mechanisms of
chlorine dioxide reaction with different lignin structures. Few attempts
have however been made to elucidate the kinetic behavior of these
reactions, esp. the reaction with non-phenolic lignin structures. Kinetic
studies have therefore now been carried out on the reaction between
chlorine dioxide and models of representative lignin units present in
residual lignin of oxygen-bleached kraft pulp. Literature data for the
reaction of phenols indicate that the rate of reaction of lignin-like
phenolic models is about 105 times faster than the rate of reaction of
non-phenolic groups in lignin. In the pH-interval used during industrial
bleaching (pH 2-4), the fraction of ionized phenols is extremely low with
a concn. about 10-6 times that of non-ionized phenolic groups so that, in
spite of their high reactivity, they contribute only moderately to the total
rate. Thus, although the total rate of reaction of phenols is faster, this
does not exclude the importance of chlorine dioxide reactions with
non-phenolic groups which are predominantly in the residual lignin. The
influence of pH on the degrdn. of lignin models has also been studied.
It was found that a pH higher than 4 gives less chlorination in the arom.
nuclei and more oxidn., esp. in the side chain where the a-hydroxyl
group is oxidized to the a-carbonyl group. However, too high a pH
gives less delignification. It seems that different lignin structures
respond differently to pH-changes during bleaching.
252.
128:39901
Study on release rate of gel-type solid chlorine dioxide.
Zhou, Dajun; Liu, Yuejin; Xiong, Shuangxi; Ling, Jianxiong; Chen,
Change (Dep. Chem. Eng., Xiangtan Univ., Xiangtan 411105, Peop.
Rep. China). Wujiyan Gongye, (5), 3-5 (Chinese) 1997 Wujiyan
Gongye Bianjib. CODEN: WUGOFJ. ISSN: 1006-4990. DOCUMENT
TYPE: Journal CA Section: 66 (Surface Chemistry and Colloids)
A gel-type solid ClO2 on an agar base was prepd. by rapid mixing of an
agar contg. an acid activator with a resin (having high absorptivity for
liq.) impregnated with 0.02M ClO2 and the release rate of the solid
ClO2 was studied. The effects of the type and the content of absorbent
resin, ClO2 concn. of the impregnating soln., acid activator type and
content, and temp. on the release rate were examd.
253.
128:39352
Drinking water filtration system using positively charged filtration
system.
Baumann, E. Robert; Rozelle, Lee (Puraq Water Systems, Inc., USA).
PCT Int. Appl. WO 9741960 A1 13 Nov 1997, 67 pp. DESIGNATED
STATES: W: AL, AM, AT, AU, AZ, BA, BB, BG, BR, BY, CA, CH, CN,
CU, CZ, DE, DK, EE, ES, FI, GB, GE, GH, HU, IL, IS, JP, KE, KG, KP,
KR, KZ, LC, LK, LR, LS, LT, LU, LV, MD, MG, MK, MN, MW, MX, NO,
NZ, PL, PT, RO, RU, SD, SE, SG, SI, SK, TJ, TM, TR, TT, UA, UG, UZ,
VN, YU, AM, AZ, BY, KG, KZ, MD, RU, TJ, TM; RW: AT, BE, BF, BJ,
CF, CG, CH, CI, CM, DE, DK, ES, FI, FR, GA, GB, GR, IE, IT, LU, MC,
ML, MR, NE, NL, PT, SE, SN, TD, TG. (English). (World Intellectual
Property Organization). CODEN: PIXXD2. CLASS: ICM:
B03C005-00. ICS: C02F001-00; C02F009-00; C02F001-78;
C02F001-76; B01D037-00. APPLICATION: WO 97-US7106 29 Apr
1997. PRIORITY: US 96-642535 3 May 1996. DOCUMENT TYPE:
Patent CA Section: 61 (Water)
This invention comprises a process and app. for producing purified
drinking water from surface or ground fresh water sources using no
chem. pre-treatment or coagulants, by usage of a pos.-charged
filtration media to attract the typically neg.-charged suspended solids
present in the water source. The process, which can be portable,
includes a filtration system having a filtration/recirculation/backwash
component and a disinfection step. The process further includes a
system controller which receives elec. signals from float controls to
control the filtration, recirculation, and backwash steps. This process
produces drinking water which meets or exceeds the guidelines set by
the World Health Organization for turbidity and microbiol. content.
254.
128:39131
Gaseous, chlorine-free chlorine dioxide for drinking water.
Gordon, Gilbert; Rosenblatt, Aaron (Department of Chemistry, Miami
Univ., Oxford, OH 45056, USA). Chem. Oxid., Volume Date 1995, 5,
250-259 (English) 1997 Technomic Publishing Co., Inc. CODEN:
CHOXEC. ISSN: 1072-2459. DOCUMENT TYPE: Journal; General
Review CA Section: 61 (Water) Section cross-reference(s): 49
A review with 9 refs. The benefits of applying chlorine dioxide (ClO2)
for the oxidative treatment of drinking water are well established. Ests.
have been made that over 700 utilities in the United States use or have
the capabilities to use ClO2 for disinfection. Chlorine dioxide treated
finished water typically has substantially lower trihalomethane (THM)
levels because ClO2 will not form chlorinated org. species as a
byproduct of disinfection. In fact, many utilities rely on ClO2 to meet the
100 mg/L THM max. contamination level (MCL) mandated in current
drinking water regulations. An emerging regulatory issue concerning
the formation of disinfection byproducts (DBPs) is causing the water
industry to set stds. for the generation and delivery of ClO2. The
Federal Register (11 Feb. 1994) contains language developed to limit
the prodn. of unwanted inorg. byproducts (namely chlorite (ClO2-) and
chlorate (ClO3-) ions) by requiring utilities to maintain high (95%)
generation efficiencies and by limiting the amt. of excess Cl2 that can
be used during the generation process. The efficiency and excess Cl2
regulations may be problematic for utilities that overchlorinate to attain
chlorine dioxide high yields. This situation is a double edged sword.
Many utilities will have to decide either to reduce the amt. of Cl2 used to
react with sodium chlorite (NaClO2), thereby increasing the ClO2-
residual in finished water, or else overchlorinate to increase yields and
surpass the excess Cl2 limits. A new ClO2 technol. that meets the
forthcoming regulations has been developed. The novel ClO2
generation system delivers essentially 100% ClO2 that is Cl2 free. The
process also eliminates ClO2- and ClO3- that are often produced in
traditional generators or carried through such systems as a result of
poor generation efficiency. The technol. affords infinite turndown
capability, meaning that if a smaller or larger dose of ClO2 is required
to meet changing demand or seasonal variations, a system
recalibration is not required to maintain generator efficiency. This
eliminates a common problem assocd. with ClO2 generation when
water flow through the treatment plant changes unexpectantly and
reduces generator efficiency.
255.
128:39027
Characterization of effluents from chlorine dioxide substitution
bleaching and oxygen-reinforced extraction.
Yetis, Ulku; Ataberk, Selale; Gokcay, Celal F.; Sahin, Sebnem M.
(Environmental Engineering Department, Middle East Technical
University, Ankara 06531, Turk.). Water Sci. Technol., 36(2-3,
Pretreatment of Industrial Wastewaters II), 353-360 (English) 1997
Elsevier Science Ltd. CODEN: WSTED4. ISSN: 0273-1223.
DOCUMENT TYPE: Journal CA Section: 60 (Waste Treatment and
Disposal) Section cross-reference(s): 43
The effects of ClO2 substitution for elemental Cl in the chlorination
stage, aimed at the minimization of chlorinated orgs. and subsequent O
reinforcement in the proceeding extn. stage on the characteristics of
bleaching effluents were examd. The characteristics of the effluents
were assessed in terms of mol. wt. distribution by gel filtration, so that
alternatives for the treatment of these effluents can be proposed. The
anal. of chlorination and extn. stage effluents with different ClO2
substitution levels and varying available Cl charges using a Sephadex
G-50 column have indicated that indeed a marked change in the mol.
wt. distribution of chlorinated org. compds. have occurred. The mol.
size of chlorinated org. compds. in the chlorination stage has increased
with the ClO2 substitution, while that in the extn. stage has decreased
when compared with the mol. size of these compds. in original
bleaching effluents with only elemental Cl used in the chlorination stage
and followed by extn. stage. Mol. size of the chlorinated org. compds.
in the chlorination stage effluents was not seriously affected by the ClO2
substitution level; while it was increased greatly by the increased total
Cl dosage. In the extn. stage effluents, ClO2 substitution level has not
appeared to be an important parameter influencing the mol. size
distribution.
256.
128:38749
Measurements of arctic sunrise surface ozone depletion events at
Kangerlussuaq, Greenland (67癗, 51癢).
Miller, Henry L.; Weaver, Alex; Sanders, Ryan W.; Arpag, Karen;
Solomon, Susan (Aeronomy Lab., Univ. Colorado, Boulder, CO, USA).
Tellus, Ser. B, 49B(5), 496-509 (English) 1997 Munksgaard
International Publishers Ltd. CODEN: TSBMD7. ISSN: 0280-6509.
DOCUMENT TYPE: Journal CA Section: 59 (Air Pollution and Industrial
Hygiene) Section cross-reference(s): 53
In-situ measurements of surface O3 were conducted from Jan. through
May 1995 at Kangerlussuaq, Greenland. Several O3 depletions were
obsd., the most severe during 14-17 Mar. (<10 ppbv; typical ~40 ppbv).
Simultaneous near-UV/VIS spectroscopic measurements yielded total
column values for BrO and OClO. Elevated BrO levels were obsd. at
the onset of O3 depletion episodes. The BrO column resides in the
boundary layer. The boundary layer BrO mixing ratio (>13 pptv)
showed correlation with surface O3 depletion, whereas OClO values
showed no correlation.
257.
128:36233
Nitrogen dioxide in ECF and TCF bleaching sequences.
Rosal, Alfonso; Vidal, Teresa; Colom, Jose F. (Especialidad Papelera
y Grafica. E.T.S.I.I. de Terrassa, Terrassa 08222, Spain). Int. Symp.
Wood. Pulping Chem., 8th, Volume 2, 367-372. Gummerus Kirjapaino
Oy: Jyvaskyla, Finland. (English) 1995. CODEN: 65KDAY.
DOCUMENT TYPE: Conference CA Section: 43 (Cellulose, Lignin,
Paper, and Other Wood Products)
Oxygen delignification, following pretreatment of Eucalyptus globulus
kraft pulp with nitrogen dioxide, permits the prodn. of ECF and TCF fully
bleached pulps. The use of 0.5% NO2 increases the delignification
after the oxygen stages. However, the introduction of NO2 increases
the yellowness of the pulp. To reduce this effect it is necessary to use
one of the bleaching agents: chlorine dioxide, ozone, or formamidine
sulfinic acid (FAS) after the oxygen stages. The nitrogen dioxide
treatment between two oxygen stages followed by FAS and hydrogen
peroxide, produces TCF fully bleached pulps.
258.
128:36220
Relations between cooking conditions, pulp quality and bleachability as
studied using a new superbatch experimental cooking system.
Svedman, Mikael; Tikka, Panu; Kovasin, Kari (Oy Lannen Laboratoriot
- Western Laboratories Inc., Rauma 26101, Finland). Int. Symp. Wood.
Pulping Chem., 8th, Volume 2, 201-206. Gummerus Kirjapaino Oy:
Jyvaskyla, Finland. (English) 1995. CODEN: 65KDAY. DOCUMENT
TYPE: Conference CA Section: 43 (Cellulose, Lignin, Paper, and Other
Wood Products)
Cooking, oxygen delignification, and ECF bleaching characteristics of
Scandinavian pine were studied using a recently implemented lab.
scale displacement cooking system. Cooking with white liquor was
varied over a wide range in order to produce pulps of varying
delignification degrees and yields with const. impregnation and hot
black liquor treatment. The pulps were then oxygen delignified and
bleached with a D(EOP)DD sequence, again varying conditions in
order to evaluate delignification and brightness development.
Unbleached and bleached pulps were analyzed and tested in terms of
PFI-beating and pulp strength. The results show that the alkali profile
after the two-stage pretreatment with black liquors dets. the
delignification speed and delignification selectivity in displacement
kraft batch cooking. Bleachability, i.e. the active chlorine consumption
to a certain brightness level, was significantly better for cooks done at
higher alkali concns. Yield saving by using a low alkali charge impairs
bleachability.
259.
128:36211
Elimination of chromophoric structures in modern kraft pulp bleaching
sequences.
Annergren, Goran; Boman, Maria; Olsson, Elisabeth; Wikman, Bengt;
Osterberg, Folke (SCA Technology Centre, Sundsvall 850 03, Swed.).
Int. Symp. Wood. Pulping Chem., 8th, Volume 1, 745-752. Gummerus
Kirjapaino Oy: Jyvaskyla, Finland. (English) 1995. CODEN: 65KDAY.
DOCUMENT TYPE: Conference CA Section: 43 (Cellulose, Lignin,
Paper, and Other Wood Products)
As a continuation of a study about the removal of light absorbing
material and residual lignin in different bleaching sequences
[prebleaching with elemental chlorine as well as elemental chlorine-free
(ECF) and total chlorine-free (TCF) full bleaching], using a dioxane
extn. for pyrolysis-gas chromatog.-mass spectroscopic and FTIR
investigations of extd. lignin, changes in light absorption of the lignin
material during the extn. have been illustrated in material balances.
The difference between light absorption and lignin after peroxide
bleaching which employs only the selective peroxide bleaching region
and those after a high-intensity peroxide bleaching which is continued
in the following stagnating region has been investigated in accordance
with the earlier studies.
260.
128:36208
Formation of chloro-organics during chlorine bleaching of softwood
kraft pulp.
Rajan, P. S.; Chen, C. -L.; Gratzl, J. S. (Department of Wood and
Paper Science, North Carolina State University, Raleigh, NC
27695-8005, USA). Int. Symp. Wood. Pulping Chem., 8th, Volume 1,
713-720. Gummerus Kirjapaino Oy: Jyvaskyla, Finland. (English)
1995. CODEN: 65KDAY. DOCUMENT TYPE: Conference CA
Section: 43 (Cellulose, Lignin, Paper, and Other Wood Products)
Section cross-reference(s): 59, 60
The formation of chloro-orgs. during chlorine bleaching was studied
using high and low relative mol. mass (HRMM and LRMM) pine kraft
lignins as models. When the HRMM lignin was treated with a mixt. of
chlorine-chlorine dioxide (50% substitution) by dropwise addn., the
content of total organically bound chlorine (TOCI) of the chlorination
mixt. was reduced significantly (~ 80% redn.) compared to that resulting
from one charge addn. with chlorine only. Further, the formation of
absorbable org. halogen compds. (AOX) was reduced by about 50%.
The formation of 4-chlorophenol derivs. was also reduced appreciably.
4,5-Dichloroguaiacol, 4,5-dichlorocatechol, and 2,4,6-trichlorophenol
were the major monomeric products in the chlorination mixts. The
rather high yield of 2,4,6-trichlorophenol suggested that appreciable
amts. of compression wood lignin present in the furnish.
261.
128:36203
Surface properties of bleached kraft pulp fibers and their comparison
with the properties of the final paper products.
Laine, Janne; Stenius, Per (Laboratory of Forest Products Chemistry,
Department of Forest Products Technology, Helsinki University of
Technology, ESPOO FIN-02150, Finland). Int. Symp. Wood. Pulping
Chem., 8th, Volume 1, 589-596. Gummerus Kirjapaino Oy: Jyvaskyla,
Finland. (English) 1995. CODEN: 65KDAY. DOCUMENT TYPE:
Conference CA Section: 43 (Cellulose, Lignin, Paper, and Other Wood
Products)
Unbleached softwood kraft pulp was O delignified and bleached using
either H2O2 and O3 or ClO2. The surface properties of the fibers were
investigated after each bleaching stage. The influence of the surface
properties on the strength and bulk properties of paper products and
pulps was evaluated. The surface coverage of the fibers by lignin and
extractives was analyzed using variable angle ESCA (XPS). The amts.
and accessibilities of carboxyl groups in pulps were analyzed using
adsorption of cationic polyelectrolytes. O3 removed significantly more
of the surface lignin than the av. decrease in lignin content of the pulp.
On the other hand, the fraction of surface lignin removed by O and H2O2
was smaller than the total decrease in lignin content. The effect of ClO2
on the surface lignin content depended strongly on the no. of
treatments. The amt. of surface charge decreased by ~50% and ~5%
by O3 and H2O2 treatments, resp., whereas a slight increase was
obtained when fibers were O delignified. ClO2 decreased the charge,
but the extent of decrease varied between stages. The surface charge
of bleached pulps was obsd. to correlate with tensile strength, light
scattering coeff., and brightness reversion.
262.
128:36164
Chromophore changes during chemical pulp bleaching. A study by
absorption spectroscopy.
Mcgrouther, Kim G.; Pasco, Maria F.; Suckling, Ian D. (PAPRO-New
Zealand, NZ Forest Research Institute Ltd, Rotorua, N. Z.). Int. Symp.
Wood. Pulping Chem., 8th, Volume 3, 85-90. Gummerus Kirjapaino
Oy: Jyvaskyla, Finland. (English) 1995. CODEN: 65KDAY.
DOCUMENT TYPE: Conference CA Section: 43 (Cellulose, Lignin,
Paper, and Other Wood Products)
UV/visible absorption spectra were used to follow changes in the
chromophores in pine kraft pulps through each stage of a no. of
different bleaching sequences. The bleaching stages investigated
were: O delignification (O); transition metal ion removal (Q);
pre-bleaching with Cl (C), ClO2 (D), or O3 (Z); O-fortified extn. (Eo); and
final brightening with ClO2 (D) or H2O2 (P). In some stages, e.g. O
delignification and treatment with ClO2, removal of specific
chromophores was obsd., but the identity of these chromophores still
needs to be detd.
263.
128:36160
The role of xylan and glucomannan in yellowing of kraft pulps.
Buchert, Johanna; Bergnor, Elisabeth; Lindblad, Gunnar; Viikari, Liisa;
Ek, Monica (VTT Biotechnology and Food Research FIN-02044 VTT,
Finland). Int. Symp. Wood. Pulping Chem., 8th, Volume 3, 43-48.
Gummerus Kirjapaino Oy: Jyvaskyla, Finland. (English) 1995. CODEN:
65KDAY. DOCUMENT TYPE: Conference CA Section: 43 (Cellulose,
Lignin, Paper, and Other Wood Products)
The effects of xylan and glucomannan on the thermal stability of
unbleached, partially bleached, and fully bleached pine and birch kraft
pulps were studied. The choice of bleaching chems. strongly affected
the brightness reversion. Compared with hydrogen peroxide or
chlorine dioxide, bleaching with ozone reduced the amt. of carboxyl
groups and subsequently the pc-nos. of oxygen-delignified pulps. Xylan
removal reduced also the amt. of carboxyl groups in the pulps and this
was reflected in improved brightness stability whereas glucomannan
removal had no effect. Thus, the uronic acids bound to pulp xylan were
found to participate in the brightness reversion of kraft pulps.
264.
128:36152
EFC bleached hardwood kraft pulp at Arkhangelsk pulp and paper mill.
Tarannikov, N. M.; Ivanov, N. I.; Davydova, T. G.; Gorshkov, V. A.;
Malkov, Yu. A.; Egorova, N. I. (OTK, Russia). Tsellyul., Bum., Karton,
(9-10), 12-14 (Russian) 1997 Tsellyuloza, Bumaga, Karton. CODEN:
TBKAEY. ISSN: 0869-4923. DOCUMENT TYPE: Journal CA Section:
43 (Cellulose, Lignin, Paper, and Other Wood Products) Section
cross-reference(s): 60
Replacing elemental chlorine in bleaching of hardwood kraft pulp with
an elemental chlorine-free (ECF) bleaching sequence comprising (1)
acid pretreatment with HCl, (2) pre-bleaching with ClO2, (3) alk. extn.,
(4) hypochlorite bleaching, (5) bleaching with ClO2, (6) alk. extn., and
(7) post bleaching with ClO2 resulted in improved properties of the pulp
and significant decrease of AOX in the filtrates from various bleaching
stages.
265.
128:26674
Pilot study: the use of high-purity, chlorine-free chlorine dioxide to
minimize trihalomethane formation.
Long, Bruce W.; Miller, Robert F.; Rosenblatt, Aaron A. (CDG
Technology, Inc., New York, NY, USA). Chem. Oxid., Volume Date
1996, 6, 126-133 (English) 1997 Technomic Publishing Co., Inc.
CODEN: CHOXEC. ISSN: 1072-2459. DOCUMENT TYPE: Journal
CA Section: 61 (Water)
Increasingly restrictive regulation of chlorination byproducts and
concerns about chlorine-resistant pathogens (Giardia;
Cryptosporidium) have moved the Indianapolis Water Company (IWC)
to evaluate alternatives to chlorine for drinking water disinfection; the
alternatives being considered by IWC include chlorine-free chlorine
dioxide. Chlorine dioxide is a powerful, highly selective oxidant that
cannot be shipped and, therefore, must be generated on site, as
needed; its benefits for drinking water treatment are well established.
However, several factors, including functional limitations of conventional
chlorine dioxide generation methods and concerns about the possible
toxicity of chlorine dioxide disinfection byproducts, have substantially
limited the use of chlorine dioxide to niche applications. New methods
for post-disinfection removal of chlorine dioxide byproducts, and
advanced technol. for on-site generation of high-purity, chlorine-free
chlorine dioxide, are among recent developments that are making
chlorine dioxide broadly applicable. IWC's chlorine dioxide work has
focused initially on minimizing formation of trihalomethanes (THM)
during water treatment. IWC's tests have employed the first pilot scale
chlorine dioxide generator to use gas:solid technol. that has been
shown in bench scale studies to produce 100% chlorine dioxide gas (in
an inert carrier) that is substantially free of the free chlorine, chlorite ion,
and chlorate ion typically assocd. with other chlorine dioxide generation
methods. The gas:solid generator enjoys infinite turndown capability,
functioning at high efficiency at 0-100% of nameplate capacity, without
the need for recalibration between dosage settings. Exptl. work
conducted at IWC's White River North (WRN) treatment plant has
consisted of tests designed to emulate the flocculation sedimentation
process employed at WRN. All samples were untreated (raw) water
dosed with both chlorine dioxide and alum, then analyzed for total
trihalomethane (TTHM) content. Chloride dioxide dosages were as
high as 6 mg per L (mg/L); TTHM levels of samples treated with the
chlorine dioxide were no higher than 10.4 mg per L (mg/L), compared to
69 mg/L for controls. When the data were cor. for TTHM content of the
chlorine dioxide stock solns. attributable to the WRN finished water
used to make up such solns., the TTHM content resulting from the
chlorine dioxide treatment was essentially nil.
266.
128:26478
Back-washing method for membrane separation apparatus for
prevention of permeation deterioration of separation membrane.
Yoshizaki, Takeshi; Ishihara, Katsuro; Narukami, Yoshihisa; Ozaki,
Toshiya; Ihara, Masahiro (Kubota, Ltd., Japan). Jpn. Kokai Tokkyo
Koho JP 09290141 A2 11 Nov 1997 Heisei, 4 pp. (Japanese).
(Japan). CODEN: JKXXAF. CLASS: ICM: B01D065-06. ICS:
B01D065-02. APPLICATION: JP 96-103016 25 Apr 1996.
DOCUMENT TYPE: Patent CA Section: 60 (Waste Treatment and
Disposal) Section cross-reference(s): 47, 61
This back-washing method is for an app. for solid.-liq. sepn. of aq. soln.
contg. sol. Mn and includes processes of sending an oxidizing agent
soln. by pressure in reverse direction to the filtration direction to a
filtered water flowing route to oxidize and decomp. org. substances
adhering to the membrane and then sending a reducing agent soln. by
pressure in the same direction in the route to reduce and dissolve
oxides of such as Mn adhering to the membrane. Durable filtration can
be carried out by the app. by the back-washing.
267.
128:26392
Chlorine dioxide provides solution for waste oil refinery.
Downing, Sherri; Rondeau, Bill; Marckini, Scott (Drew Indust. Div.,
Ashland Chem. Comp., Kansas City, KS, USA). Chem. Oxid., Volume
Date 1996, 6, 115-125 (English) 1997 Technomic Publishing Co., Inc.
CODEN: CHOXEC. ISSN: 1072-2459. DOCUMENT TYPE: Journal
CA Section: 60 (Waste Treatment and Disposal)
A West Coast oil refinery collects used oils and other lubricants from a
three state area. The oil is reprocessed at the refinery to obtain the
base lubricant. The base lubricant is then resold or is blended into new
formulations. As a result of the reprocessing, a wastewater stream is
generated. The wastewater is stored in several large tanks. The
refinery is required to meet certain wastewater effluent discharge limits
for pH, phenol, and chloroform, among others. These crit. criteria are
set at pH 6-9, phenol less than 5 ppm and chloroform less than 2 ppm.
Each tank is batch treated with chlorine dioxide prior to discharge to
the public-owned treatment works (POTW). The primary goal of using
chlorine dioxide is to comply with these discharge limits. A secondary
goal for the refinery is to treat the wastewater on a continuous basis
instead of using the batch tanks. Chlorine dioxide was batch fed to a
tanks. Chlorine dioxide was batch fed to a tank. Phenol levels were
then monitored to det. treatment effectiveness. If phenol levels were not
less than 5 ppm, second and sometimes third applications of chlorine
dioxide were needed. In these situations program costs escalated and
chloroform levels exceeded the 2 ppm limit. An alternative chlorine
dioxide equipment supplier and chems. were being used. The chlorine
dioxide generator educted the chems. through a generating column into
a large vol. of motive water. Variations in generator efficiency and
limited capacity caused unsatisfactory results. To seek a soln. to the
discharge problem, a GENEROXTM three pump chlorine dioxide
generator was then tried. Chlorine dioxide generation efficiency,
defined as the percent conversion of the sodium chlorite precursor into
chlorine dioxide, was maintained between 93-96%. The higher
efficiencies of generation led to greater oxidn. potential per gal of
sodium chlorite fed and resulted in lower residual THM formation
including chloroform, lower phenol to chlorine dioxide reaction ratios
and ultimately lower costs. The chlorine dioxide was fed at a ratio of
2.5 lb of chlorine dioxide to one pound of phenol, making a single pass
to the waste stream between storage tanks. Three 5,000 gal batches
were treated and sampled for phenol and chloroform concns. In all
three cases, phenols were well below the 5 ppm limit and the
chloroform concns. were less than 2 ppm. Results of the trial prompted
the plant to select the GENEROX three pump chlorine dioxide
generator and chems. In addn., it was decided that the chlorine dioxide
program would be re-engineered to provide treatment to a continuous
25 GPM stream as opposed to the batch tanks in order to meet the
plant's secondary goal for treatment. A split stream of concd. chlorine
dioxide was introduced at a secondary feed point to aid in phenol
destruction. This feed point acted as a polishing step prior to
discharge. Results of the continuous treatment have also been
successful. Phenol limits have been met 98% of the time while the
remaining 2% attributed to process malfunctions or loss of equipment
control upstream, directly affecting chlorine dioxide performance. The
chloroform levels have remained under the 2 ppm limit. By using a
consistently efficient chlorine dioxide generator, treatment costs were
reduced by 30% and both primary and secondary treatment goals were
achieved.
268.
128:26391
Use of chlorine dioxide for the disinfection of treated wastewater
(secondary effluent).
Masschelein, Willy J.; Mainguy, J. M.; Kernoa, Th.; Moal, M.; Dernat, M.;
Pouillot, M. (Brussels, Belg.). Chem. Oxid., Volume Date 1996, 6,
85-114 (English) 1997 Technomic Publishing Co., Inc. CODEN:
CHOXEC. ISSN: 1072-2459. DOCUMENT TYPE: Journal CA
Section: 60 (Waste Treatment and Disposal)
Present contribution reports on the leading refs. underlying the
application of chlorine dioxide in the treatment of secondary effluents of
urban wastewater treatment plants. Also data of a case study on a full
scale application in Deauville (Normandy-France) are reported.
Chlorine dioxide has at least four major advantages for disinfection of
secondary effluents: The disinfecting power is not affected by changes
in pH in the range of 5 to 9. Ammonia and Kjeldahl nitrogen (TKN) do
not affect the germicidal efficiency. Nitrite, if present is oxidized into
nitrate. Bromide ion is not significantly oxidized. Chlorine dioxide is a
powerful inactivating agent of viruses , which is also able to inactivate
spores and cysts like Clostridium perfringens and Cryptosporidium
parvum. Virucidal action is increasing at alk. pH. There is no
significant formation of trihalomethanes (THM's); formation of AOX
remains marginal. The necessary dose depends on the water quality to
be treated. It is generally in the range of 2-5 mg/L; (exceptional
maximal doses reported range 12 mg/L). With adequate mixing, two to
three minutes contact time are sufficient, but 10-15 min. are
recommendable. For the case of Deauville, the avg. dose was 4.8
mg/L (1994); the residual at discharge point avg. 0.2 mg/L. An
abatement of 2.5 to 4 logs decay of enterobacteria were achieved by
the disinfection of the treatment and 1.5 to 2 logs for Clostridium
perfringens spores. These removal rates are "addnl." to the ones
achieved by other previous treatment steps. The cost-efficiency of
chloride dioxide for disinfection of such effluents compares favorably
with other disinfectants.
269.
128:26199
Carbon monoxide emissions from oxygen delignification and chlorine
dioxide bleaching of wood pulp.
Someshwar, A. V.; Jain, A. K.; Dillard, D. S.; Caron, A. L. (NCASI,
Gainesville, FL 32614, USA). Environ. Conf. Exhib., Volume 1, 13-18.
TAPPI Press: Atlanta, Ga. (English) 1997. CODEN: 65KSAB.
DOCUMENT TYPE: Conference CA Section: 59 (Air Pollution and
Industrial Hygiene) Section cross-reference(s): 43
CO is a byproduct of bleaching pulp with ClO2 and delignification with
O2. Preliminary results from an ongoing NCASI study to investigate CO
emissions from ClO2 bleaching and O2 delignification are presented.
Continuous emission monitoring systems (CEMs) were used to
measure CO emissions from vents on four O2 delignification systems
and six bleach plants, all located in the northwestern United States.
Recent CO emission data generated by mills conducting tests in the
southeastern U.S. on four O2 delignification systems and ten bleach
plants using ClO2 were also obtained and analyzed. The CEM data
show long-term av. CO emissions to range from 0.05 to 0.4 lb/ODTBS
for the four O2 reactors, and from 0.5 to 1.2 lb/ODTBS for the six bleach
plants. Including the short-term stack test data for the southeastern O2
reactors, CO emissions appear to increase with total oxygen charge on
the brown pulp, although not all data conformed to such a relationship.
For bleaching with ClO2, CO emissions also seem to be dependent
primarily on percent ClO2 applied on the pulp, although there is
significant scatter in the data.
270.
128:26198
Carbon monoxide emissions from chlorine dioxide bleaching.
Sims, Gregory R.; Dillard, David; Dewitt, Gerald (Roy. F. Weston, Inc.,
Auburn, AL 36832, USA). Environ. Conf. Exhib., Volume 1, 7-11.
TAPPI Press: Atlanta, Ga. (English) 1997. CODEN: 65KSAB.
DOCUMENT TYPE: Conference CA Section: 59 (Air Pollution and
Industrial Hygiene) Section cross-reference(s): 43
CO is generated as a byproduct of pulp bleaching with ClO2. As ClO2
is substituted for Cl2, CO emissions may increase in quantities
sufficient to trigger Prevention of Significant Deterioration (PSD)
permitting requirements. Rayonier's Jesup, Georgia, mill plans to
increase the use of ClO2 in the first stage of a CEDED bleaching
sequence. As a result of the concern for increased CO emissions, a
testing program was conducted to monitor total bleach plant CO
emissions with varying levels of ClO2 substitution and operating
parameters in the first stage. Test results indicated that total bleach
plant CO emissions do not increase linearly with increased ClO2 usage
in the first stage, but CO reaches a max. rate. The chem. and the
kinetics of CO generation is not well understood; however, the data
indicate that increasing ClO2 substitution in the first stage may shift the
location of CO generation without significantly increasing total CO
emissions. As a result of the evaluation program, it was possible to
avoid PSD permitting for any potential increases in ClO2 substitution.
271.
128:26197
Permitting carbon monoxide emissions from bleaching operations at
pulp and paper facilities.
Keeley, S. Andrew; Orynawka, John; Hiltgen, Kenneth D. (BEandK
Environmental Co., Norcross, GA 30092, USA). Environ. Conf. Exhib.,
Volume 1, 3-6. TAPPI Press: Atlanta, Ga. (English) 1997. CODEN:
65KSAB. DOCUMENT TYPE: Conference CA Section: 59 (Air
Pollution and Industrial Hygiene) Section cross-reference(s): 43
Recent studies indicate that bleaching operations at pulp and paper
facilities are major sources of CO emissions. Some of these studies
suggest a direct link between emissions of CO and the use of ClO2
substitution in the bleaching process, which may be required under the
cluster rule. In most mills this increase in CO is significant enough to
trigger a prevention of significant deterioration (PSD) review. This
paper addresses the impact the CO emissions will have on PSD
permitting, and a preliminary detn. of Best Achievable Control Technol.
(BACT) for the control of CO from bleaching operations.
272.
128:24116
A comparison of the reactivity and efficiency of ozone, chlorine dioxide,
dimethyldioxirane and hydrogen peroxide with residual kraft lignin.
Sun, Yu. Jun; Argyropoulos, Dimitris S. (Department of Chemistry,
McGill University and Pulp and Paper Research Centre, Montreal, PQ
H3A 2A7, Can.). Int. Symp. Wood. Pulping Chem., 8th, Volume 1,
361-368. Gummerus Kirjapaino Oy: Jyvaskyla, Finland. (English)
1995. CODEN: 65KDAY. DOCUMENT TYPE: Conference CA
Section: 43 (Cellulose, Lignin, Paper, and Other Wood Products)
Residual lignin isolated from a conventional softwood (picea mariana)
kraft pulp was reacted in homogeneous solns. with varying charges of
ozone, chlorine dioxide, dimethyldioxirane (DMD) and alk. hydrogen
peroxide, followed by quant. 31P NMR analyses of their functional
groups. This effort supplied plots of relative reactivity of these reagents
toward specific functional groups present in lignin, and it revealed
salient features that control their reactivity and efficiency. The guaiacyl
phenolic units, present on the lignin, were found to be the major sites of
attack for all the surveyed oxidative treatments. At a given charge,
ozone and chlorine dioxide were found to be most efficient in causing
the formation of carboxylic acids on residual kraft lignin. Alternatively,
low charges of ozone and DMD may act as activating stages prior to
another bleaching stage, i.e., chlorine dioxide and/or alk. hydrogen
peroxide, since they were found to introduce free phenolic hydroxyl
groups in residual lignin. Most of the condensed phenolic units present
in residual kraft lignin react with the bleaching reagents surveyed.
However, it is likely that certain condensed structures are resistant to
attack. At high charges of alk. hydrogen peroxide (above 1.6%) the
extent of condensed phenolic unit elimination was similar to those
obsd. for chlorine dioxide and ozone.
273.
128:16401
Preparation of stabilized chlorine dioxide.
Xie, Huifang; He, Qihuan; Bao, Xunxiang (Inst. of Chem. Eng., Nanjing
Univ. Sci. and Technol., Nanjing 210094, Peop. Rep. China). Gongye
Shuichuli, 17(3), 14, 42 (Chinese) 1997 Gongye Shuichuli Zazhishe.
CODEN: GOSHFA. ISSN: 1005-829X. DOCUMENT TYPE: Journal
CA Section: 63 (Pharmaceuticals)
Stabilized ClO2 was prepd. by the reaction of NaClO2 and aq. HCl in
the presence of benzene to collect ClO2 in benzene, and transfer of
ClO2 into aq. Na percarbonate. The prepd. stabilized ClO2 is used as
disinfectant and germicide. The process eliminates the diln. and
transportation of gaseous ClO2 in the conventional process.
274.
128:14665
Generation of chlorine dioxide.
Yoshikawa, Akira (Yoshikawa, Akira, Japan). Jpn. Kokai Tokkyo Koho
JP 09268002 A2 14 Oct 1997 Heisei, 3 pp. (Japanese). (Japan).
CODEN: JKXXAF. CLASS: ICM: C01B011-02. APPLICATION: JP
96-114058 2 Apr 1996. DOCUMENT TYPE: Patent CA Section: 49
(Industrial Inorganic Chemicals)
Aq. chlorites are mixed with aq. H2O2 in the presence of mineral acids
at pH 4-8, preferably 5.5-7.0, to give aq. ClO2.
275.
128:14282
Selection of corrosion barriers for glass reinforced plastics (GRP)
equipment in pulp bleaching environments.
Gastaldo, Richard A.; Voruganti, Venkat; Rust, Dwight A.; Daniel, Don
W. (Ashland Chem. Company, Div. Ashland Inc., Dublin, OH 43017,
USA). BPF Compos. Congr. '96, Pap., 20th, Paper 24, 1-13. British
Plastics Federation: London. (English) 1996. CODEN: 65ICAL.
DOCUMENT TYPE: Conference CA Section: 43 (Cellulose, Lignin,
Paper, and Other Wood Products) Section cross-reference(s): 38, 57
Material selection criteria are outlined, for glass fiber - resin
composites used in pulp bleaching installations, including resin type,
corrosion barrier, cure system, and post cure schedule. These factors
can contribute to the service life of corrosion barriers of glass
reinforced plastic (GRP) equipment exposed to chlorine dioxide,
hydrogen peroxide, or sodium hydroxide ext. and/or sodium
hypochlorite. Lab. corrosion studies (ASTM C-581) and corrosion
coupon data gathered from pulp mills are described and the results
discussed. Modified phenolic novolac vinyl ester resin is preferred for
chlorine dioxide; brominated bisphenol vinyl ester resin is preferred for
sodium hypochlorite and hydrogen peroxide media; modified phenolic
novolac vinyl ester and chlorinated polyester resins are preferred for
ozone service while bisphenol polyester and bisphenol vinyl ester
resins are preferred for caustic service. For corrosion barrier veils,
carbon and synthetic veils are best for caustic and sodium hypochlorite
service, resp. This information should be of use for design engineers,
fabricators, and end users of composite equipment for pulp bleaching.
276.
128:8246
Method for producing chlorine dioxide.
Taku, Kazuo; Inazumi, Yoshinori (Suido Kiko K. K., Japan). Jpn. Kokai
Tokkyo Koho JP 09279376 A2 28 Oct 1997 Heisei, 10 pp.
(Japanese). (Japan). CODEN: JKXXAF. CLASS: ICM: C25B001-26.
APPLICATION: JP 96-113047 11 Apr 1996. DOCUMENT TYPE:
Patent CA Section: 72 (Electrochemistry) Section cross-reference(s):
49
Chlorine dioxide is prepd. by circulating a NaClO2 soln. (electrolytic
soln.) between a cation exchange diaphragmic electrolytic cell and an
electrolytic soln.-circulating tank. The electrolytic soln.-circulating tank
comprises an evapn.-degassing tower equipped with a catalytic filler in
the upper part and a soln.-storing tank in the lower part of the
electrolytic soln.-circulating tank. The evapn.-degassing tower is
connected to a vacuum device to evacuate the inside of the electrolytic
soln.-circulating tank. A portion of NaClO2 soln. is electrolyzed in the
anodic chamber of the electrolytic cell to form chlorine dioxide in the
electrolytic soln., the electrolytic soln. is sprinkled in the
evapn.-degassing tower to evap. the water in the electrolytic soln.,
gas-liq. contact is carried out between the electrolytic soln. and the
steam evapd. from the surface of the catalytic filler . The chlorine
dioxide in the electrolytic soln. is absorbed by the steam and is taken
out from the evapn.-degassing tower using the vacuum device. The
sepn. of chlorine oxide from the electrolytic soln. is easy.
277.
130:259406
Photodissociation of OClO and Ar/OClO and H2O/OClO clusters
studied by the resonance enhanced multiphoton ionization-time of flight
method.
Kreher, Christoph J.; Carter, Robert T.; Huber, J. Robert
(Physikalisch-Chemisches Institut, Universitat Zurich, Zurich CH-8057,
Switz.). J. Chem. Phys., 110(7), 3309-3319 (English) 1999 American
Institute of Physics. CODEN: JCPSA6. ISSN: 0021-9606.
DOCUMENT TYPE: Journal CA Section: 74 (Radiation Chemistry,
Photochemistry, and Photographic and Other Reprographic
Processes)
The photodissocn. of jet-cooled OClO following excitation into the A 2A2
state at around 350 nm was investigated in homogeneous OClO and
large heterogeneous Ar/OClO and H2O/OClO clusters (estd. cluster
size n ~800-2600) by probing the O (3P) and ClO (X 2P)
photofragments using the resonance enhanced multiphoton
ionization-time of flight technique. Action spectra, photofragment
excitation spectra and photofragment speed distributions were
recorded and compared to those for monomer dissocn. OClO was
found to occupy both surface and interior sites in the heterogeneous
clusters with the percentage of surface and interior dissocn. processes
being ~50% for large cluster sizes. Both O and ClO photofragments
generated in the cluster interior are translationally thermalized with
T~300 K and the ClO fragments are strongly rotationally and
vibrationally relaxed. This is most important for vibration as monomer
dissocn. yields ClO contg. up to 8 vibrational quanta at this photolysis
wavelength. Photodissocn. on the cluster surface is found to proceed
with little interaction with the cluster host. The distribution of
counter-fragment masses leads to a broadening of the speed
distributions compared with monomer dissocn. In addn., cluster chem.
was found to occur in OClO-rich heterogeneous clusters as manifested
by detection of O photofragments with velocities exceeding the highest
thermodynamically possible value. This result, consistent with that from
homogeneous OClO cluster dissocn., indicates the presence of small
OClO aggregates on the surface and within heterogeneous clusters.
From a standpoint of atm. chem., H2O/OClO clusters yield a substantial
fraction of thermalized primary photofragments, in contrast to OClO
monomer dissocn.
278.
131:290584
Treatment of printing and dyeing wastewater by coagulation-ClO2
oxidation process.
Chen, Honglin; Zhang, Changshou; Su, Jing (Jingjiang Environmental
Monitoring Station, Jingjiang 214500, Peop. Rep. China). Huagong
Huanbao, 19(4), 223-226 (Chinese) 1999 Huagong Huanbao Bianjibu.
CODEN: HUHUFD. ISSN: 1006-1878. DOCUMENT TYPE: Journal
CA Section: 60 (Waste Treatment and Disposal) Section
cross-reference(s): 40
The reaction mechanism and process flow of the basic AlCl3
coagulation-ClO2 oxidn. process for treatment of printing and dyeing
wastewater were introduced. The effluent was colorless, with COD 108
mg L-1 and ClO2 content 0.15 mg L-1.
279.
131:289105
Process for extracting gold using bromine-containing leaching solution.
Yu, Yaoji; Bai, Xuyong; Zhang, Anmin (Hebei Geology College, Peop.
Rep. China). Faming Zhuanli Shenqing Gongkai Shuomingshu CN
1137067 A 4 Dec 1996, 8 pp. (Chinese). (People's Republic of
China). CODEN: CNXXEV. CLASS: ICM: C22B003-06.
APPLICATION: CN 1995-105351 26 May 1995. DOCUMENT TYPE:
Patent CA Section: 54 (Extractive Metallurgy)
The process comprises crushing, furnishing, roasting, soaking, paste
mixing, and sepg. solid with liq. Au is extd. by roasting the crushed Au
ores, soaking the crushes in the leaching soln. with solid/liq. ratio
1:(0.3-0.5) for 15-20 min, mixing a slurry to have solid/liq. ratio 1:2,
filtering through enriching plastic foam- or activated carbon-packed
absorbing column to enrich the Au content, and recovering Au by
conventional process. The leaching soln. consists of bromide 0.8-1.2,
H2SO4 1.8-2.0, ClO2 0.05-0.1, NaCl 1%, and water balance.
280.
131:288460
Apparatus and process for manufacturing stable chlorine dioxide.
Wang, Mingqin (Peop. Rep. China ). Faming Zhuanli Shenqing
Gongkai Shuomingshu CN 1138554 A 25 Dec 1996,5 pp. (Chinese).
(People's Republic of China). CODEN: CNXXEV. CLASS: ICM:
C01B011-02. APPLICATION: CN 1995-111079 20 Jun 1995.
DOCUMENT TYPE: Patent CA Section: 49 (Industrial Inorganic
Chemicals)
The app. comprises an outlet which is located on the top of a reactor, a
inlet for H2O, methanol and catalyst which is located above the inlet of
concd. H2SO4, a solid discharge outlet which is located at bottom of the
reactor, a static mixer which is located between the middle outlet of the
reactor with heat transfer and inlet of concd. H2SO4, and a inlet for inert
gas, NaClO3, NaCl, and water which is located between the heat
exchanger and the solid discharge outlet. The manufg. process
comprises prepg. 40% NaClO3 soln. A, 7% methanol soln. B (contg.
0.25% acid anhydride catalyst), absorbing liq. C (contg. H2O: SON-27:
30% hydrogen peroxide wt. ratio 20:1:1.5); feeding the soln. into a
reactor at a speed to give A:B:C wt. ratio 1:1:0.66; and controlling the
pH at 8.2-8.6 at the end of absorption.
281.
131:280692
Spectrophotometric determination of chlorine dioxide with Active
Scarlet Red K 2BP.
Feng, Yijun; Fu, Qinghong; Xie, Jiali; Shen, Yeqing; Du, Bingfan
(Department of Chemistry, Sichuan University, Chengdu 610064,
Peop. Rep. China). Lihua Jianyan, Huaxue Fence, 35(6), 268-269
(Chinese) 1999 Jixie Gongyebu Shanghai Cailiao Yanjiuso. CODEN:
LJHFE2. ISSN: 1001-4020. DOCUMENT TYPE: Journal CA Section:
79 (Inorganic Analytical Chemistry)
A method for the spectrophotometric detn. of ClO2 with Active Scarlet
Red K 2BP was presented. ClO2 can oxidize Active Scarlet Red K
2BP and cause color-fading of the dyestuff. The detg. wavelength was
535 nm, the linear range 0.172-6.72 mg/mL, and the upper and lower
detection limits were 6.72 and 0.172 mg/mL resp. ClO3- and ClO- had
interferences on the detn. The results were consistent with those by
iodometry.
282.
131:273990
Chemically induced stimulation of subterranean carbonaceous
formations with aqueous oxidizing solutions.
Riese, Walter C.; Bross, Stephen V. (Vastar Resources, Inc., USA).
U.S. US 5967233 A 19 Oct 1999, 9 pp., Cont.-in-part of U.S.
5,669,444. (English). (United States of America). CODEN: USXXAM.
CLASS: ICM: E21B043-17. ICS: E21B043-26; E21B043-27;
E21B043-40. NCL: 166263000. APPLICATION: US 1997-934585 22
Sep 1997. PRIORITY: US 1996-594725 31 Jan 1996. DOCUMENT
TYPE: Patent CA Section: 51 (Fossil Fuels, Derivatives, and Related
Products)
A method for increasing the prodn. of methane from a subterranean
carbonaceous formation by chem. stimulating the formation of addnl.
free surface area or cleats in the org. constituents of the formation and
by causing inorganically adsorbed methane to be released from
contained clay-minerals to increase the rate of methane desorption
from the formation by injecting an aq. oxidizing soln. contg. at least one
oxidant into the formation, and thereafter producing methane from the
formation at an increased rate. Suitable oxidants include peroxide,
ozone, oxygen, chlorine dioxide, sodium hypochloride, water sol. salts
of hypochlorous acid, perchlorate, chlorate, persulfate, perborate,
percarbonate, permanganate, nitrate and combinations thereof.
283.
131:273296
Ecological development in elemental chlorine free bleaching.
Nakamata, Keiichi (Technical & Development Div., Hokuetsu Paper
Mills, Ltd., Japan). Kami Parupu Gijutsu Taimusu, 42(5), 38-43
(Japanese) 1999 Tekku Taimusu. CODEN: KPGTAW. ISSN:
0453-1507. DOCUMENT TYPE: Journal CA Section: 43 (Cellulose,
Lignin, Paper, and Other Wood Products)
The company's Niigata Mill started full-scale operation of the ECF plant
with an initial capacity of 400,000 mtpy in Mar. 1998. The plant strongly
supports the operation of No.8 on machine coater started in June of
last year and has realized the company's policy of "Friendly paper
making with the earth and human race". ECF bleaching is the method
using ClO2 as the main constituent without using chlorine gas in chem.
pulp bleaching. The resulting effects were: large elimination of org.
chlorine compds. from waste water compared to traditional bleaching,
increase of both viscosity and brightness of obtained pulps, the
decrease in both chromaticity and AOX of waste water. Under the
current circumstances of the increasing interests in environmental
problems, the market's response to ECF bleaching has increased
greatly. The article states the merits of ECF bleaching focusing on the
following four points: (1) ensuring people's health, (2) promoting the
confidence and pride of sales persons by product discrimination, (3)
increasing sales amts. and (4) establishing strong confidence among
regional people.
284.
131:268300
Sterilizing and deodorant gas-feeding apparatus and sterilization and
deodorization system.
Aoyagi, Kohei; Fujita, Sanai (Sun Seal K. K.; Fujita, Sanai, Japan).
Jpn. Kokai Tokkyo Koho JP 11285525 A2 19 Oct 1999 Heisei, 7 pp.
(Japanese). (Japan). CODEN: JKXXAF. CLASS: ICM: A61L002-20.
ICS: A61L009-015. APPLICATION: JP 1998-76467 11 Mar 1998.
PRIORITY: JP 1998-37971 5 Feb 1998. DOCUMENT TYPE: Patent
CA Section: 5 (Agrochemical Bioregulators) Section
cross-reference(s): 59
The app., which sterilizes and deodorizes bedding, cloths, wards,
inside space of ambulances, etc., comprises (1) a hot air-supplying
unit, (2) a ventilation duct which is connected to (1) and has a gas
discharge opening, and (3) a detachable container of gel prepns.
showing sterilizing, antiseptic, preservative, insecticidal, mothproofing,
or deodorant effect such as stabilized ClO2, installed to the duct. The
app. may be equipped with an ozonizer near the gas discharge
opening. Also claimed is a sterilization and deodorization system
composed of the app. and an adsorption unit to remove used ClO2
from exhaust gas. The system can utilize ClO2 without risk of explosion
because ClO2 is made into a gel prepn.
285.
131:268294
Deodorant and antimicrobial aerosol compositions containing pure or
stabilized chlorine dioxide solution.
Abe, Koji (Business Plan K. K., Japan). Jpn. Kokai Tokkyo Koho JP
11269017 A2 5 Oct 1999 Heisei, 5 pp. (Japanese). (Japan).
CODEN: JKXXAF. CLASS: ICM: A01N059-08. ICS: A01N025-06;
A61L002-22; C01B011-02; C09K003-30. APPLICATION: JP
1998-38922 20 Feb 1998. DOCUMENT TYPE: Patent CA Section: 5
(Agrochemical Bioregulators) Section cross-reference(s): 59, 62, 63
Deodorant and antimicrobial aerosols comprise (1) a soln. contg.
dissolved ClO2 gas, chlorite, and pH-adjusting agent or a stabilized
ClO2 soln. with sodium chlorite or lithium chlorite as the main
component, (2) surfactant, (3) the antifoaming agent, and (4) propellant.
The aerosols can deodorize and disinfect a room within a short time
without generating stains due to water in furnishings. Thus, water was
added to stabilized ClO2 (Purogene) to make a soln. dild. to 2000 ppm,
and 969 mL of this soln., 1 g sodium alkylsulfonate (surfactant), 0.5 mg
liq. paraffin (antifoaming agent), and liquefied butane (propellant) were
put into an airtight container and agitated at room temp. to make an
aerosol.
286.
131:264653
Low-energy dissociation of OClO following electron capture.
Senn, Gilbert; Drexel, Herwig; Marston, George; Mason, Nigel J.; Mark,
Tilmann D.; Meinke, Martina; Schmale, Carola; Tegeder, Petra; Ruhl,
Eckart; Illenberger, Eugen (Institiut fur Ionenphysik der Leopold
Franzens Universitat, Innsbruck A-6020, Austria). J. Phys. B: At., Mol.
Opt. Phys., 32(14), 3615-3626 (English) 1999 Institute of Physics
Publishing. CODEN: JPAPEH. ISSN: 0953-4075. DOCUMENT
TYPE: Journal CA Section: 74 (Radiation Chemistry, Photochemistry,
and Photographic and Other Reprographic Processes)
The authors studied neg. ion formation following low-energy electron
impact (0-10 eV) on OClO including a time-of-flight anal. of the ions.
The dominant feature is formation of a transient neg. ion (OClO-*) by
resonant electron capture in the vicinity of 0.7 eV which decomps. into
Cl-, O-, ClO- and O2-. The total dissociative attachment (DA) cross
section at the resonance max. (0.7 eV) is near 10-15 cm2 with ClO- + O
the dominant channel. Although the DA reaction O2 + Cl- is exothermic
by nearly 4 eV the Cl- ion appears with a mean kinetic energy of only
0.4*0.1 eV indicating effective vibrational excitation of neutral O2. Also
obsd. at higher target gas pressures is the parent anion ClO2- which
arises from an effective charge transfer process involving a metastable
complex formed in the collision between the dominant DA product ClO-
and the sample mol. OClO. Possible implications of these results for
the heterogeneous chem. of OClO on polar stratospheric cloud
particles are considered.
287.
131:264645
Control of the Chlorine Dioxide-Iodine-Malonic Acid Oscillating
Reaction by Illumination.
Munuzuri, Alberto P.; Dolnik, Milos; Zhabotinsky, Anatol M.; Epstein,
Irving R. (Department of Chemistry and Volen Center for Complex
Systems, Brandeis University, Waltham, MA 02454-9110, USA). J.
Am. Chem. Soc., 121(35), 8065-8069 (English) 1999 American
Chemical Society. CODEN: JACSAT. ISSN: 0002-7863.
DOCUMENT TYPE: Journal CA Section: 74 (Radiation Chemistry,
Photochemistry, and Photographic and Other Reprographic
Processes) Section cross-reference(s): 78
The authors show that illumination of the chlorine
dioxide-iodine-malonic acid reaction with visible light suppresses
oscillations and shifts the steady state of the reaction to lower concns.
of iodide ions. In the system with starch, illumination results in a strong
decrease of the steady-state concn. of the triiodide-starch complex.
The authors suggest a simple mechanism, in which iodine atoms
produced by photodissocn. of mol. iodine initiate redn. of chlorine
dioxide to chlorite and oxidn. of iodide ions to iodine. This results in a
decreased amplitude of oscillations and, at more intense illumination,
the cessation of oscillations. Illumination also lowers the steady-state
concns. of iodide and the triiodide-starch complex. Results obtained
from numerical simulations are in good agreement with the exptl. data.
288.
131:263894
Chlorine dioxide generation for water treatment.
Cowley, Gerald; Lipsztajn, Marek; Ranger, George Joseph; Schaible,
Ron K.; Tran, Ty V.; Lawless, Darren F. (Sterling Pulp Chemicals, Ltd.,
Can.). U.S. US 5965004 A 12 Oct 1999, 14 pp., Cont.-in-part of U.S.
Ser. No. 545,792, abandoned. (English). (United States of America).
CODEN: USXXAM. CLASS: ICM: C25B001-00. NCL: 205499000.
APPLICATION: US 1997-959031 28 Oct 1997. PRIORITY: US
1996-545792 13 Mar 1996. DOCUMENT TYPE: Patent CA Section:
72 (Electrochemistry) Section cross-reference(s): 61
Chlorine dioxide is generated by electrochem. oxidn. of sodium chlorite
in an anode compartment of a cation-exchange membrane-divided cell
in the presence of significant quantities of sodium chlorate and is
recovered in a suitable recipient medium by passing the chlorine
dioxide through a hydrophobic microporous membrane. Water
balance in a continuous operation is maintained by removing water
from the anolyte by transporting the same partly across the hydrophobic
microporous membrane in vapor form and partly across the
cation-exchange membrane.
289.
131:261604
Accidental release prevention.
Charrington, Peter R. (Environmental Resources Management, Exton,
PA 19341, USA). Ceram. Trans., 87(Environmental Issues and Waste
Management Technologies in the Ceramic and Nuclear Industries III),
89-99 (English) 1998 American Ceramic Society. CODEN: CETREW.
ISSN: 1042-1122. DOCUMENT TYPE: Journal CA Section: 59 (Air
Pollution and Industrial Hygiene)
Under Title III of the Clean Air Act Amendments of 1990 (CAAA), both
the Occupational Health and Safety Administration (OSHA) and the
Environmental Protection Agency (EPA) had to promulgate rules for
facilities that handle regulated substances requiring them to prep.
hazard assessments of facilities. OSHA is accomplishing this activity
through its Process Safety Management (PSM) program, while EPA is
addressing its requirements with the Risk Management Program Rule
under Section 112 (r) of the CAAA. The final rule was signed on 24
May 1996 and published in the Federal Register on 20 June 1996. It is
estd. that approx. 66,000 facilities will be effected by the EPA's Rule,
some of which are already covered under the OSHA PSM regulations.
Even though compliance with the 112 (r) requirements is 21 June 1999,
the time to det. applicability and develop cost-effective compliance
strategies is now. This paper will assist you in understanding the
regulations and in developing an effective strategy to reduce the risk of
accidental releases.
290.
131:259804
Chemically induced stimulation of cleat formation in a subterranean
coal formation.
Riese, Walter C.; Bross, Stephen V. (Vastar Resources, Inc., USA).
U.S. US 5964290 A 12 Oct 1999, 8 pp., Cont.-in-part of U.S.
5,669,444. (English). (United States of America). CODEN: USXXAM.
CLASS: ICM: E21B043-17. ICS: E21B043-26; E21B043-27;
E21B043-40. NCL: 166263000. APPLICATION: US 1997-934722 22
Sep 1997. PRIORITY: US 1996-594725 31 Jan 1996. DOCUMENT
TYPE: Patent CA Section: 51 (Fossil Fuels, Derivatives, and Related
Products)
This invention relates to a method for increasing the prodn. of methane
from a subterranean coal formation by chem. stimulating the formation
of cleats in the formation to increase the rate of methane prodn. from
the formation by injecting an aq. oxidant soln. into the formation to
stimulate the formation of cleats in the formation; and thereafter
producing methane from the formation at an increased rate. Suitable
oxidants include chlorine dioxide, metallic salts of perchlorate, chlorate,
persulfate, perborate, percarbonate, permanganate, nitrate and
combinations thereof.
291.
131:259556
Chlorine dioxide gel or foaming composition and containers for
inserting the composition.
Abe, Koji (Business Plan K. K., Japan). Jpn. Kokai Tokkyo Koho JP
11278808 A2 12 Oct 1999 Heisei, 8 pp. (Japanese). (Japan).
CODEN: JKXXAF. CLASS: ICM: C01B011-02. ICS: A01N025-06;
A01N025-16; A01N059-00; B65D030-02; C08K003-24; C08K005-09;
C08K007-22; C08L101-14. APPLICATION: JP 1998-335690 26 Nov
1998. PRIORITY: JP 1997-329049 28 Nov 1997. DOCUMENT TYPE:
Patent CA Section: 49 (Industrial Inorganic Chemicals)
The ClO2-based soln. comprises dissolved ClO2 gas, chlorites, and pH
adjusting agent. Chlorite is lithium chlorite, and pH adjusting agent is
citric acid. The soln. can be formed into gel by absorption into a
high-water absorption resin or mixed with a foaming agent to give a
foaming product. The gel or foam products are stored in a laminated
container manufd. by binding films of polyethylene terephthalate,
polyethylene, and aluminum together with a binder. The ClO2-based
soln. can be used as disinfectants, deodorants, and bactericides.
292.
131:259518
Comparison of different ClO2 processes from a technical and
economical point of view.
Dahl, Anders (Celchem AB, Swed.). Kami Pa Gikyoshi, 53(8),
978-984 (Japanese) 1999 Kami Parupu Gijutsu Kyokai. CODEN:
KAGIAU. ISSN: 0022-815X. DOCUMENT TYPE: Journal CA Section:
49 (Industrial Inorganic Chemicals)
Three different ClO2 processes are compared basically including
following parameters: (1) consumption of raw materials and utilities, (2)
prodn. of byproducts, (3) product quality, (4) operational characteristics,
(5) process features, and (6) costs of operation and investment. The
selected processes are (1) SVP-LITE/R8, methanol based process,
world-wide the most common process used today, (2) HP-A process,
peroxide based process, of special interest in Japan because of easy
conversion and capacity expansion from existing R2/Mathieson plants,
and (3) integrated process, where ClO2 generation is integrated with
chlorate electrolysis and hydrochloric acid prodn.
293.
131:259112
Elimination of fluorescence from wastepaper or papermaking white
water by treating wastepaper with kraft pulping chlorine bleaching
solutions or treating papermaking white water with discharged kraft
pulping chlorine bleaching solutions.
Nishino, Fumiaki (Mitsubishi Paper Mills, Ltd., Japan). Jpn. Kokai
Tokkyo Koho JP 11269788 A2 5 Oct 1999 Heisei, 7 pp. (Japanese).
(Japan). CODEN: JKXXAF. CLASS: ICM: D21C005-02. ICS:
D21C009-14. APPLICATION: JP 1998-70063 19 Mar 1998.
DOCUMENT TYPE: Patent CA Section: 43 (Cellulose, Lignin, Paper,
and Other Wood Products)
Fluorescence-free wastepaper pulp is prepd. by mixing 3-50% (on kraft
pulp) beaten deinked or bleached wastepaper pulp with kraft pulp and
bleaching the mixts. with kraft pulp bleaching solns. in *1 chlorine
bleaching step. Fluorescence of papermaking white water is
eliminated by mixing papermaking white water (A) contg. fluorescent
dyes with discharged chlorine bleaching solns. (B) obtained from *1
kraft pulping chlorine bleaching step to cause A-B wt. ratio 1:1-100. A
slurry contg. colored wastepaper (degree of fluorescence 4.1) 20,
NaOH 0.8, and DI-1200 (deinking agent) 0.08% was beaten 30 min at
room temp.and washed and an aq. slurry contg. the pulp and 0.1%
H2O2 was kept 2 h at 60* to give a deinked pulp. A slurry contg. the
deinked pulp and 0.1% (on pulp) ClO2 was stirred 60 min at room
temp. to give a wastepaper pulp with degree of fluorescence 0.0 and
degree of whiteness 87.8%.
294.
131:259069
Kraft lignin recovery from black liquor.
Patel, Piyush V.; Rane, V. C. (Absorption Cooling Division of Thermax
Ltd., Pune, India). Chem. Ind. Dig., 12(2), 114-118 (English) 1999
Blockdale. CODEN: CINDEM. ISSN: 0971-5266. DOCUMENT
TYPE: Journal CA Section: 43 (Cellulose, Lignin, Paper, and Other
Wood Products)
Different processes available for the kraft lignin recovery from black
liquor are described and compared for economic feasibility. Acid pptn.
provides superior sepn. at lower capital and operating costs compared
to ultrafiltration. The ClO2 generator waste acid may be used to
recover 10-15% of the total lignin without affecting the sulfur balance of
the mill. For further recovery, acidification using CO2 may be used. For
the CO2 acidification process with dried lignin as byproduct, payback
period of about 4 yr is expected.
295.
131:256526
Determination of Chlorate and Chlorite and Mutagenicity of Seafood
Treated with Aqueous Chlorine Dioxide.
Kim, Jeongmok; Marshall, Maurice R.; Du, Wen-Xian; Otwell, W. Steve;
Wei, Cheng-I. (Food Science and Human Nutrition Department,
University of Florida, Gainesville, FL 32611-0370, USA). J. Agric.
Food Chem., 47(9), 3586-3591 (English) 1999 American Chemical
Society. CODEN: JAFCAU. ISSN: 0021-8561. DOCUMENT TYPE:
Journal CA Section: 17 (Food and Feed Chemistry)
The use of chlorine dioxide (ClO2) as a potential substitute for aq.
chlorine to improve the quality of seafood products has not been
approved by regulatory agencies due to health concerns related to the
prodn. of chlorite (ClO2-) and chlorate (ClO3-) as well as possible
mutagenic/carcinogenic reaction products. Cubes of Atlantic salmon
(Salmo salar) and red grouper (Epinephelus morio) were treated with
20 or 200 ppm aq. chlorine or ClO2 solns. for 5 min, and exts. of the
treated fish cubes and test solns. were checked for mutagenicity using
the Ames Salmonella/microsome assay. No mutagenic activity was
detected in the treated fish samples or test solns. with ClO2. Only the
sample treated with 200 ppm chlorine showed weak mutagenic activity
toward S. typhimurium TA 100. No chlorite residue was detected in
sea scallops, mahi-mahi, or shrimp treated with ClO2 at 3.9-34.9 ppm;
however, low levels of chlorate residues were detected in some of the
treated samples. In most cases, the increase in chlorate in treated
seafood was time- and dose-related.
296.
Observations and interpretation of column OClO seasonal cycles at two
polar sites.
Miller, Henry L., Jr.; Sanders, Ryan W.; Solomon, Susan (Aeronomy
Laboratory, NOAA, Boulder, CO, USA). J. Geophys. Res., [Atmos.],
104(D15), 18769-18783 (English) 1999 American Geophysical Union.
CODEN: JGRDE3. ISSN: 0148-0227. DOCUMENT TYPE: Journal
CA Section: 59 (Air Pollution and Industrial Hygiene) Section
cross-reference(s): 53
OClO and NO2 slant column abundances have been measured by
ground-based spectrographs in both the Arctic (Kangerlussuaq,
Greenland, at 67.0癗, 51.0癢) and the Antarctic (McMurdo Station,
Antarctica, at 77.8癝, 166.6癊). A key process for stratospheric ozone
depletion is the activation of chlorine by heterogeneous reactions.
Sunlight is also an essential ingredient in the catalytic cycles that
destroy ozone. This data set illustrates the seasonal timing of autumnal
chlorine activation and the springtime disappearance of active chlorine
at two polar sites. As such, the data provide constraints for model
calcns. In the Northern Hemisphere during the winters of 1994-1995
and 1995-1996, the OClO data show the seasonal onset of
stratospheric chlorine activation in mid-Dec. and seasonal
disappearance of active chlorine in mid-Mar. The data also show the
seasonal decline and recovery (in mid-Mar.) of nitrogen dioxide levels.
In the Southern Hemisphere during the winters of 1991, 1993, and
1996, similar chem. processing occurs during late Apr. to early May
and late Sept. to early Oct. The role of several factors in detg. the
seasonal cycles of column OClO are probed through model studies.
Obsd. cold temps. and reactions on liq. sulfate aerosols appear to play
a key role in producing the timing of the obsd. OClO seasonal cycle in
the Northern Hemisphere.
297.
131:247300
The measurement of active chlorine in the atmosphere by chemical
amplification.
Perner, D.; Arnold, T.; Crowley, J.; Klupfel, T.; Martinez, M.; Seuwen, R.
(Max Planck Institut fur Chemie, Mainz 55020, Germany). J. Atmos.
Chem., 34(1), 9-20 (English) 1999 Kluwer Academic Publishers.
CODEN: JATCE2. ISSN: 0167-7764. DOCUMENT TYPE: Journal
CA Section: 59 (Air Pollution and Industrial Hygiene) Section
cross-reference(s): 79
Chem. amplification, CA, a method commonly used for the detection of
peroxy radicals, HO2 and RO2, was found to be sensitive towards ClOx
(Cl + ClO + OClO) as well. ClOx is reduced by NO to Cl atoms which
react with carbon monoxide in the presence of O2. The reaction
sequence thus initiated oxidizes CO to CO2 and NO to NO2, with a
chain length of 300 * 60. This allows the atm. ClOx content to be
measured under ambient conditions with a detection limit of better than
1 ppt. In parallel peroxy radicals are indicated with a chain length of
160 * 15. Chem. amplification is not specific and does not indicate
which radical chain it is seeing. Identification relies solely on
plausibility. During the ARCtic Tropospheric Ozone Chem. (ARCTOC)
campaign in spring 1995 and 1996 the CA technique was used at
Ny-Alesund. ClOx at mixing ratios of up to 2 ppt were found in the
boundary layer under certain conditions. The low concns. of ClOx
indicate that the arctic boundary ozone depletion is mainly driven by
bromine.
298.
131:245226
Chlorine dioxide generator.
Deacon, Peter W.; McLaughlin, Jess (Vulcan Chemical Technologies,
Inc., USA). PCT Int. Appl. WO 9951332 A1 14 Oct 1999, 17 pp.
DESIGNATED STATES: W: AE, AL, AU, BA, BB, BG, BR, CA, CN,
CU, CZ, EE, GD, GE, HR, HU, ID, IL, IN, IS, JP, KP, KR, LC, LK, LR,
LT, LV, MG, MK, MN, MX, NO, NZ, PL, RO, SG, SI, SK, SL, TR, TT,
UA, UZ, VN, YU, ZA, AM, AZ, BY, KG, KZ, MD, RU, TJ, TM; RW: AT,
BE, BF, BJ, CF, CG, CH, CI, CM, CY, DE, DK, ES, FI, FR, GA, GB,
GR, IE, IT, LU, MC, ML, MR, NE, NL, PT, SE, SN, TD, TG. (English).
(World Intellectual Property Organization). CODEN: PIXXD2. CLASS:
ICM: B01J008-02. ICS: C01B011-02. APPLICATION: WO
1999-US6315 23 Mar 1999. PRIORITY: US 1998-53815 2 Apr 1998.
DOCUMENT TYPE: Patent CA Section: 49 (Industrial Inorganic
Chemicals)
An app. and method for generating chlorine dioxide are described.
Reagents are introduced into the lower end of a reaction column
through "V" inlets. The reagent column surrounds a center column
through which motive fluid moves upwardly into a nozzle and venturi
throat to produce a zone of reduced pressure at the upper end of the
reaction column . The reagents move upwardly through the column
interacting throughout 360 degrees. Reaction product exits the
generator through the venturi throat.
299.
131:230622
Simple kit for generating chlorine dioxide solution.
Ogawa, Katsutoshi; Oyama, Shoko (Chisso Corp., Japan). Jpn. Kokai
Tokkyo Koho JP 11255502 A2 21 Sep 1999 Heisei, 8 pp.
(Japanese). (Japan). CODEN: JKXXAF. CLASS: ICM: C01B011-02.
ICS: A01N059-00; A61L002-18; A61L009-01. APPLICATION: JP
1998-73034 9 Mar 1998. DOCUMENT TYPE: Patent CA Section: 49
(Industrial Inorganic Chemicals)
The kit comprises an inner container having 3 independent
compartments for sep. holding chlorite soln., hypochlorite soln., and
hydrochloric acid and an outer container having a cylindrical intrusion
for holding the inner container in position without having the 3 solns.
mixing together unwantedly. Chlorine dioxide is used as deodorants or
disinfectants and can be obtained simply by mixing the 3 solns.
together.
300.
131:230195
Chlorine dioxide bleaching of lignocellulosic materials with additives.
Jiang, Zhi-Hua; Van Lierop, Barbara; Berry, Richard M. (Pulp and
Paper Research Institute of Canada, Can.). PCT Int. Appl. WO
9947744 A1 23 Sep 1999, 29 pp. DESIGNATED STATES: W: AE,
AL, AM, AT, AU, AZ, BA, BB, BG, BR, BY, CA, CH, CN, CU, CZ, DE,
DK, EE, ES, FI, GB, GD, GE, GH, GM, HR, HU, ID, IL, IN, IS, JP, KE,
KG, KP, KR, KZ, LC, LK, LR, LS, LT, LU, LV, MD, MG, MK, MN, MW,
MX, NO, NZ, PL, PT, RO, RU, SD, SE, SG, SI, SK, SL, TJ, TM, TR, TT,
UA, UG, UZ, VN, YU, ZW, AM, AZ, BY, KG, KZ, MD, RU, TJ, TM; RW:
AT, BE, BF, BJ, CF, CG, CH, CI, CM, CY, DE, DK, ES, FI, FR, GA,
GB, GR, IE, IT, LU, MC, ML, MR, NE, NL, PT, SE, SN, TD, TG.
(English). (World Intellectual Property Organization). CODEN: PIXXD2.
CLASS: ICM: D21C009-14. APPLICATION: WO 1999-CA225 12
Mar 1999. PRIORITY: US 1998-PV78042 16 Mar 1998. DOCUMENT
TYPE: Patent CA Section: 43 (Cellulose, Lignin, Paper, and Other
Wood Products)
A method has been developed which enhances the effectiveness of
chlorine dioxide bleaching of lignocellulosic materials. It is effected by
adding to the chlorine dioxide bleaching stage an aldehyde compd. at
a concn. of from about 0.01 % to about 20 %, by wt. of the oven-dried
lignocellulosic material.