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Salt in industrySalt is all around you. Many, even most, of the products you see are produced from salt or using salt in their manufacture. Industries use most of the salt produced in the world today. The biggest single use of salt is also one of the least known. Salt is the feedstock for the chlor-alkali chemical industry, just as oil is for the petrochemical industry. The difference: we are not running out of salt! Chlorine chemistry brings consumers clean water, soaps and detergents, many medications, PVC pipes for our homes, cell phones, cosmetics, protective suits for SCUBA divers – and astronauts, digital cameras, flat panel TVs, electron microscopes, solar panels for energy production. The list is essentially endless. Manufacturing textiles, glass, rubber, leather, even drilling oil wells, depends on salt. Salt has 14,000 known uses. Salt in chlorine chemistrySalt is the feedstock of the chlor-alkali industry which produces chlorine, caustic soda and the myriad other products formed from these basic chemicals. The chemical industry well-describes the chemical genealogy of salt with its “Chlorine Tree.” Globally, chlorine chemistry is the single largest market for salt, although in the U.S., where there are numerous areas with exploitable salt deposits, the salt produced for chemical production is often extracted directly by chemical companies and not by salt producers. In Europe and Japan, the chlor-alkali industry is more likely to buy its salt from a salt company. Chemical companies pass an electrical current through saturated salt brine in a salt bridge, producing a oxidation-reduction (redox) chemical reaction. This electrolysis separates the gaseous chlorine, (Cl2), from the sodium hydroxide (caustic soda). Chlorine is an effective disinfectant and bleach. We use it to keep drinking water safe. Downstream, vinyl chloride and polyvinyl chloride (PVC) and their derivatives are produced from chlorine. Caustic soda is used in pulp processing, and to make cellulose chemicals and their derivatives. Sodium chlorite is used in the textile industry. Other chemicals manufactured from salt are metallic sodium and sodium chlorate. Until 1986, salt was used to produce synthetic soda ash (NaCO3) in the U.S. by the Solvay process. Soda ash is now obtained naturally from trona mines. Salt-based chemicals are used:
Other industrial uses of saltIt would be difficult to list all of the thousands of industries that use salt as a raw material or ingredient. The major industries include: Textile and dyeing. Salt is used to fix dyes and to standardize dye batches Metal processing, such as aluminum refining. Salt is used to remove impurities Rubber manufacturing. Salt separates the rubber from latex Oil and gas drilling. Salt is used to produce a drilling mud that prevents widening of bore holes in rock salt strata, inhibits fermentation, and increases mud density Pharmaceuticals. Salt is used for tablet and caplet polishing, the production of intraveneous saline solutions and for manufacturing hemodialysis solutions used for kidney machines Animal hide processing and leather tanning. Salt is used to cure, preserve, and tan hides Pigment manufacture. Salt is a grinding agent Ceramics manufacture. Salt acts to vitrify heated clays Soap making. Salt separates glycerol from water Detergent production. Salt is used as a filler. Just a few of salt’s other industrial uses include.
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