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Zinc dithionite

Zinc Dithionite. Zinc dithionite [7779-86-4] is a white, water-soluble powder. Although it exhibits somewhat greater stabiHty in... [Pg.151]

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]

Zinc Dithionite. Zinc dithionite [7779-86-4], ZnS204, is a white, water-soluble powder. Although it exhibits somewhat greater stability in aqueous solution compared to sodium dithionite at a given temperature and pH, it is no longer used in the United States because of regulatory constraints on pollution of water by zinc. [Pg.151]

The use of sodium or zinc dithionite ("hydrosulfite") represents the most common type of reducing bleaching. Usually 0.5-1% sodium dithionite of the dry pulp weight is added and the bleaching is allowed to proceed at 50°-60°C for 1 -2 hours. Because ions of heavy metals catalyze the decomposition of dithionite solutions, complexing agents, such as EDTA, are added as stabilizers. [Pg.166]

Theoretical considerations reveal that the bleaching effect of dithionite reaches a maximum at pH 8-9 at temperatures of 20°-60°C. However, because oxygen cannot be excluded from the system, a lower pH region is used in practice (pH 5-6) to avoid the oxidation of dithionite. If zinc dithionite is used, the best effect is reached at a still lower pH value. [Pg.166]

SYNS DITHIONOUS. CID, ZINC SALT (1 1) ZINC DITHIONTTE ZINC DITHIONITE (DOT) ZINC HYDROSL LFITE... [Pg.1449]

The organic ground on which these observations fell was fertile. The reducing power of aldehydes was well known, for example the use of formaldehyde (together with zinc dithionite) in the dye industry. ... [Pg.79]

Zinc dust process Liquid or gaseous sulfur dioxide is reacted with zinc dust in an aqueous suspension at 40°C to zinc dithionite ... [Pg.122]

ZINC DITHIONITE (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.1249]

Dithionites ( 204 ). Both sodium and zinc dithionite have found use in the bleaching of mechanical pulps and textiles. The preparation of the dithionite ion is accomplished via the reduction of the bisulfite ion and sulfur dioxide with Zn dust. [Pg.156]

Zinc dithionite, a widely-used bleach component which, on contact with moisture, generates sulphur dioxide, a sharp-smelling and irritating gas. [Pg.159]

Some examples of articles in Class 9 are engines, internal combustion life-saving appliances, self-inflating battery-powered equipment or vehicle. Some examples of substances in Class 9 are blue, brown or white asbestos carbon dioxide (Dry ice) Environmentally hazardous substance, liquid/solid, n.o.s. Zinc dithionite. ICAO 2-9.1... [Pg.160]

Examples included in this class Asbestos Carbon dioxide, solid (dry ice) Consumer commodity Chemical and First aid kits Environmentally hazardous substance Life-saving appliances Engines, internal combustion Vehicles (flammable gas powered). Vehicles (flammable liquid powered) Polymeric beads Battery-powered equipment or vehicles Zinc dithionite Genetically modified organisms and micro-organisms which are not infectious substances but which are capable of altering animals, plants, or microbiological substances in a way which is not normally the result of natural reproduction. lATA 3.9.14... [Pg.160]

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

Water-Reactive Liquid, corrosive. 3129 39 Zinc Dithionite 1931 32... [Pg.744]

See other pages where Zinc dithionite is mentioned: [Pg.433]    [Pg.151]    [Pg.149]    [Pg.254]    [Pg.254]    [Pg.1036]    [Pg.151]    [Pg.149]    [Pg.254]    [Pg.254]    [Pg.1448]    [Pg.1943]    [Pg.122]    [Pg.1345]    [Pg.1346]    [Pg.252]    [Pg.799]    [Pg.420]    [Pg.1093]    [Pg.394]    [Pg.896]    [Pg.526]    [Pg.147]    [Pg.109]   
See also in sourсe #XX -- [ Pg.128 ]

See also in sourсe #XX -- [ Pg.128 ]



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