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Zinc hydrosulfite

Zinc hydrosulfite (zinc dithionite) is a powerhil reducing agent used in bleaching paper and textiles it is prepared from zinc dust and sulfur dioxide ... [Pg.398]

Although it has been reported (138) that decolorization of wastewater containing reactive azo dyes with sodium hydrosulfite is possible only to a limited extent, others have demonstrated good reduction (decolorization). For example, using zinc hydrosulfite for the decolorization of dyed paper stock (139) resulted in color reduction of 98% for azo direct dyes (139). A Japanese patent (140) describes reducing an azo reactive dye such as Reactive Yellow 3 with sodium hydrosulfite into its respective aromatic amines which ate more readily adsorbable on carbon than the dye itself. This report has been confirmed with azo acid, direct, and reactive dyes (22). [Pg.382]

The recommended treatment option for control of toxic pollutants regulated under PSES categorical standards is chemical substitution. Although chemical substitution of sodium hydrosulfite for zinc hydrosulfite is recommended for control of zinc at groundwood mills, PSES for zinc were calculated using treatment performance data for lime precipitation.39... [Pg.891]

It is often possible to use different process chemicals to accomplish the same goal. For example, both zinc hydrosulfite and sodium hydrosulfite can be used to bleach mechanical pulps. The substitution of the use of sodium hydrosulfite for zinc hydrosulfite was prompted, at least in part, by the establishment of effluent limitations controlling the discharge of zinc. Other opportunities exist to minimize the discharge of toxic and nonconventional pollutants through chemical substitution. [Pg.892]

Zinc formaldehyde sulfoxylates, 23 677 Zinc forming-die alloys, 26 594 Zinc foundry alloys, 26 591-594 Zinc hydrosulfite (dithionite), 26 559 Zinc hydroxypyridmethione biocide for antifouling coatings,... [Pg.1036]

SYNS DITHIONOUS acid, zinc salt (1 1) ZINC HYDROSULFFTE ZINC HYDROSULFITE (DOT)... [Pg.1449]

Ammonium Phosphate 7779-86-4 Zinc Hydrosulfite 7790-69-4 Lithium Nitrate... [Pg.1092]

Zinc hydrosulfite, ZnS-iO,. Mol. wt. 193.50, readily soluble in water. Supplier Virginia Chemicals. [Pg.650]

Zinc hydrosulfite, developed in the mid-1950s, was inexpensively made at the mill site by reacting powdered zinc with common pulp mill chemicals (Eq. 15.40). [Pg.485]

This powerful reducing agent produces brightness improvements of 10-12 points, if care is taken to exclude oxygen. Any oxygen present wastes a part of the active reducing capacity from the very rapid (probably only diffusion limited) reaction of zinc hydrosulfite with oxygen (Eq. 15.41). [Pg.485]

However, the disposal of spent groundwood bleach liquor from zinc hydrosulfite has posed zinc toxicity problems for shellfish, so that mills have now switched to sodium hydrosulfite. This is equally effective (although more expensive) and avoids this problem. Sodium hydrosulfite is made at the mill from purchased sodium borohydride (Eq. 15.42). [Pg.485]

Zinc Hydrosulfite Zinc Nitrate Zinc Sulfate Zinc Sulfide... [Pg.480]

ZINC HYDROSULFITE (7779-86-4) Reacts with water, steam, or acids, forming corrosive acid solution and sulfur oxide fumes. Incompatible with lead diacetate, mercury(I) chloride. Aqueous solution is incompatible with oxidizers, strong acids, alkalis, ammonia, aliphatic amines, alkanolamines, alkylene oxides, amides, epichlorohydrin, organic anhydrides, isocyanates, nitromethane, vinyl acetate. Attacks metals in the presence of moisture. [Pg.1250]

Zinc distearate. See Zinc stearate Zinc dithionite. See Zinc hydrosulfite Zinc ditolyl sulfinate dihydrate... [Pg.4750]

Potassium phosphate Sodium metasilicate 2,2,6,6-Tetramethyl-4-piperidinol bleaching agent mfg. 4,4 -Diaminostilbene-2,2 -disulfonic acid bleaching agent, animal glue Zinc hydrosulfite... [Pg.4911]

Sodium perborate Sodium perborate tetrahydrate Sodium percarbonate Sodium peroxide Sodium silicate Sodium sulfite Sulfur Sulfurous acid Zinc hydrosulfite... [Pg.4913]

Hydroxypropylcellulose Hydroxypropyl guar flotation depressant, mining Zinc hydrosulfite... [Pg.5296]

Sodium phosphoaluminate Sodium sorbate Starch, pregelatinized Zinc hydrosulfite paper/paperboard, aq./fatty food-contact Acrylates/VA copolymer Adipic acid/dimethylaminohydroxypropyl diethylenetriamine copolymer Adipic acid/epoxypropyl diethylenetriamine, copolymer Aluminum acetate Aluminum myristates/palmitates... [Pg.5504]

Vinyl acetate Zinc hydrosulfite textiles, food-packaging Linoleamide DEA PEG-14 tallate textiles, industrial Epoxy resin... [Pg.5810]

See other pages where Zinc hydrosulfite is mentioned: [Pg.1086]    [Pg.254]    [Pg.280]    [Pg.892]    [Pg.944]    [Pg.254]    [Pg.280]    [Pg.1449]    [Pg.1943]    [Pg.280]    [Pg.422]    [Pg.679]    [Pg.176]    [Pg.1069]    [Pg.1082]    [Pg.1345]    [Pg.1346]    [Pg.41]    [Pg.133]    [Pg.1093]    [Pg.1093]    [Pg.4753]    [Pg.4895]    [Pg.4913]    [Pg.4913]    [Pg.4913]    [Pg.4924]    [Pg.5314]    [Pg.6250]   
See also in sourсe #XX -- [ Pg.892 ]



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Hydrosulfites

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