Caustic soda using bleach

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. 

Preparation for Dyeing. A hot alkaline scour with a synthetic surfactant and with 1% soda ash or caustic soda is used to remove size, lubricants, and oils. Sodium hypochlorite is sometimes included in the alkaline scouring bath when bleaching is requked. After bleaching, the polyester fabric is given a bisulfite rinse and, when requked, a further scouring in a formulated oxahc acid bath to remove mst stains and mill dkt which is resistant to alkaline scouring. 

Not usually necessary in the field. If necessary for enclosed areas, use HTH, STB, household bleach, caustic soda, or DS2. Decontaminate liquid agent on the skin with the M258A1, M258, or M291 skin decontaminating kit. Decontaminate individual equipment with the M280 individual equipment decontamination kit. 

Persistency household bleach, caustic soda, dilute alkali solutions, or decontaminating solution number 2 (DS2) are effective on equipment. Use steam and ammonia or hot, soapy water in a confined area. Depends upon munitions used and the weather, ffeavily splashed liquid persists 1-2 days under average weather conditions. GD is calculated to evaporate about 4x as slowly as water. Addition of agent thickeners can greatly increase persistency. 

The chlorine value can be converted into hypochlorite bleach by absorption into lime or caustic soda. It can also be used to produce hydrogen chloride by combining with hydrogen in a burner. The latter technique is particularly useful when the acid can be consumed on site in brine acidification or ion-exchange resin regeneration. Another approach that has found some favour in the past is the absorption of the chlorine into a solvent from which it could then be stripped and returned to the liquefaction plant. 

The first cut fibers are the longer and are used mainly for padding, upholstery, mattresses, etc. Second cut linters are suitable for the prepn of various NC s after special treatment consisting of boiling in caustic soda, followed by bleaching... 

A factory in which soda ash is made is called an alkali works. A works using the Leblanc process is divided into several departments (1) The acid works where sulphuric acid is made (2) Salt-cake works (3) Black-ash works and lixiviation (4) White-ash (soda ash) works or caustic soda works (5) Bleaching powder works where the hydrogen chloride from the salt-cake works is converted into chlorine, and the latter converted into bleaching powder and (6) Sulphur extraction from tank-waste. The following is a diagrammatic representation of the Leblanc process ... 

When bleach is used, hypochlorous acid is formed but also caustic soda, which tends to increase the pH, so extra vigilance may be needed if this is used in galvanized cooling towers. 

This is one of the largest electrochemical industries in the world. It consists in the electrolysis of sodium chloride as brine to give chlorine and caustic soda. Chlorine is used in the preparation of vinyl chloride for PVC, as a bleaching agent for paper and paper pulp, as a disinfectant, besides other chloration applications. Caustic soda is important in mineral processing, and in the paper, textile, and glass industries. Table 15.2 shows recent data for industrial consumption of chlorine and caustic soda in the USA. 

Caustic Soda The common name for sodium hydroxide (NaOH). Used as a bleaching chemical. 

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