Pulp and paper bleaching

Sodium sulfite [7757-83-7] which is used in pulp and paper bleaching, is usually produced by the reaction of sulfur dioxide with either caustic soda or soda ash. 

Uses Chlorine is used for water purification and in decreasing amounts for pulp and paper bleaching. Some is used for metallurgical purposes such as metal extraction. Its largest use is for the production of organic compounds used in plastics, pesticides, herbicides, refrigeration fluids, solvents, and others. 

IR spectrophotometry, 661, 662 TEARS assay, 667 hydroperoxide oxidation, 692 Upid hydroperoxides, 977-8 decomposition, 669 DNA adducts, 978-84 protein adducts, 984-5 ozone adducts, 734 ozonide reduction, 726 ozonization characterization, 737, 739 peroxydisulfate reactions, 1013, 1018 Alkali metal ozonides, 735-7 Alkaline peroxide process, pulp and paper bleaching, 623... 

In other oxygen applications, metal fabrication involves cutting and welding with an oxygen-acetylene torch. Chemical manufacture use includes the formation of ethylene oxide, acrylic acid, propylene oxide, and vinyl acetate. Miscellaneous uses include sewage treatment, aeration, pulp and paper bleaching, and missile fuel. 

Dioxin is formed as a by-product of many industrial processes involving chlorine such as waste incineration, chemical and pesticide manufacturing, and pulp and paper bleaching. Dioxin was the primary toxic component in Agent... 

Hydrogen peroxide is a green chemical that only leaves water or 02 as byproducts. Thus, it is increasingly used to bleach pulp and paper, bleach... 

This chapter will focus on three important industries where peroxygens have had a significant impact, particularly with respect to environmental issues chemical purification, pulp and paper bleaching and hydrometallurgy and metal finishing. 

Worldwide, chlorine is mainly utilized in the manufacture of PVC, for pulp and paper bleaching, water treatment and... 

There is no direct use of chlorine in pulp and paper bleaching as of 1996, since all the Western European paper mills have shifted their bleaching operations to the... 

In this section, some details will be given of two other key industries where the uses of peroxygens are very much linked to environmental factors pulp and paper bleaching and metal extraction, recovery and finishing. 

The areas of application of alloy C-22 are many of the same as those for alloy C-276. It is being used in the pulp and paper bleaching systems, pollution control systems, and various areas in the chemical process industry. 

Toren, K., Blanc, P.D., 1997. The history of pulp and paper bleaching respiratory-health effects. Lancet 349,1316-1318. 

About 50% of the world s production of hydrogen peroxide in 1994 was used for pulp-and paper-bleaching. Other bleaching applications are becoming more important as hydrogen peroxide is seen as an environmentally benign alternative to chlorine-based bleaches. 

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