Whiten, pulp

After the chemical treatment, the pulped wood is removed, washed, and screened. Unbleached, brown-colored paper is made directly for this material. Most whitened or bleached paper is made by the treatment of the pulp with chlorine, chlorine dioxide, hypochlorite, and/or alkaline extraction. In general, sulfate-pulped paper is darker and requires more bleaching and alkaline extraction to give a white pulp. 

Brightening - pLUORESCENT WHITENING AGENTS] (Volll) -of mechanical pulps pULP](Vol20)... 

Sodium chlorite is a powerful and stable oxidizing agent and is capable of bleaching much of the coloration in cellulosic materials without weakening the cellulose fibers. It finds uses in the pulp and textile industries, particularly in the final whitening of kraft paper. 

M Scheringer, K Haider, and K Hungerbuhler. Comparing the environmental performance of fluorescent whitening agents with peroxide bleaching of mechanical pulp. J. Ind. Ecol. 3 77-95, 2000. 

Uses Emulsifier for food processing, personal care, and industrial applies, (paints, pulp/paper, agric., metalworking, textiles, etc.) dispersant for dry coffee whiteners... 

Chem. Descrip. Sorbitan stearate CAS 1338-41-6 EINECS/ELINCS 215-664-9 Uses Emulsifier for food processing (chocolate and confectionery coatings) and personal care prods. volume improver in icings and fillings dispersant in dry coffee whiteners, flavor oils emulsifier for pulp/paper, pharmaceuticals, metalworking, lubricants, textiles, agric., paints, adhe-... 

Paper is made from the pulp of fibers from several origins, such as wood, cotton, linen, or rag. The raw material is first chemically or mechanically treated to break it down to pulp. Then, large quantities of water and other materials are added to the fiber pulp, such as resins, minerals, and dyes or whiteners. This mixture is then spread evenly over a surface and dried. At that stage, the frame of the surface and potential watermarks create identifiable patterns on the paper. Finally, the paper is cut to the required dimension. 

Direct use of chlorine is in pulp and paper manufacturing and water treatment operations. Chlorine is used in the pulp and paper industiy to bleach the pulp to produce a high-quality whitened material, devoid of dark lignin and any other undesirable residuals. Chlorine has been the most common disinfectant and is still used by municipalities and others to treat potable, process, and waste water streams. Because of this specific use of chlorine, waterborne diseases such as typhoid and cholera have been eradicated in the industrialized world. Chlorine also removes hydrogen sulfide, iron compounds, and organic species that are responsible for objectionable tastes or odor associated with water. 

Bleach systems are used in domestic laundry and cleaning applications, whitening raw cotton, pulp and paper production, and wastewater treatment. Their main task is to remove colored stains from fabrics, hard surfaces, or aqueous solutions. This is achieved by chemical degradation of the chro-mophoric units present in colored soils. In the course of the reaction, conjugated electron systems are interrupted so that the color disappears. Large molecules are broken down and polar groups are introduced, so that the stain becomes more hydrophilic and easier to dissolve or disperse. 

Uses Emulsifier for food processing, personal care, and industrial applies, (paints, pulp/paper, agric., metalworking, textiles, etc,) dispersant for dry coffee whiteners Properties Yel. soft solid, bland odor sol. in water sp.gr. 1.0 b.p. > 200 C (760 mm) HLB 10.5 acid no. 2 max. sapon. no, 88-98 hyd. no. 42-60 flash pt. (COC)... 

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