Rayon manufacture

Rayon cake Rayon manufacturers Rayon precursors g-Rays Razor... 

In theory, for regular rayon manufacture only one of the hydroxyl groups on each pair of anhydroglucose units needs to be replaced by a xanthate group, ie, the target degree of substitution (DS) is 0.5, which if achievable without waste would need 23% CS2 on ceUulose. 

Gold and gold-based alloys ate used for corrosion-resistant equipment. Gold—platinum alloys, 75 Au-25 Pt or 84 Au-15 Pt-1 Rh, ate used as cmcible material for many molten salts (98). Spinnerets for rayon manufacture ate based on the Au—Pt system which exhibits a broad miscibility gap in the soHd state so that the alloys can be age-hardened. Spinneret alloys contain 30—40% or mote platinum modified by small additions of usually rhodium (99). Either gold or gold—platinum alloys ate used in mpture disks for service with corrosive gases (100). 

Courtaulds North America, Inc. 45 La Moyne, Ala. rayon manufacture... 

In aU.S. EPA demonstration grant with the American Enka Company, a process for precipitating a dense sludge with high zinc assay was proven. The zinc in the sludge was recovered and recycled to the rayon manufacturing plant. This recycling of zinc was shown to have no ill effects on the rayon yam. 

There are ten viscose rayon manufacturing plants in the U.S., all of which are believed to use zinc sulfate in their spinning bath. This process greatly enhances the economics of removing this source of zinc pollution, allowing neutralization of the acid stream and recovery of the zinc while generating a good profit for industrial yarns and at a moderate cost for textile yams. 

Carbon disulfide (CS2) is one of the most significant sulfur compounds because of its widespread use and toxicity. This compound has two sulfur atoms, each separately bonded to a carbon atom. This compound is a volatile, colorless liquid (mp, -111°C bp, 46°C). Unlike most organosulfur compounds, it is virtually free of odor. Although its uses are declining, it has numerous applications in chemical synthesis, as a solvent to break down cellulose in viscose rayon manufacture, and in the manufacture of cellophane. It has also been used as an insecticide and fumigant. 

Dialysis operates by the diffusion of selected solutes across a nonporous membrane from high to low concentration. An early industrial application of dialysis was caustic soda recovery from rayon manufacturing. It had been a viable process because inexpensive but alkali-resistant cellulose membranes were available that were capable of removing polymeric impurities from the caustic. Gradually however, dialysis is being replaced by dynamic membrane technology for caustic soda recovery because of the latter s much higher productivity. 

Hydrogen sulfide has been widely used as a reagent in analytical chemistry. Its major use is in the production of elemental sulfur and sulfuric acid (ATSDR 1999). It is also used in the manufacture of heavy water for the nuclear energy industry, in the production of sodium sulfide and thiophenes, in rayon manufacturing, as an agricultural disinfectant, and as an additive in lubricants. 

Use Rayon manufacture, cellulosic plastics, nitrocellulose lacquers, soil-cement binder in road construction, explosives. 

Use Plating barrels, rayon-manufacturing equipment, pickling tanks, electrical and thermal insulation, oil-handling equipment, steel rolling-mill bearings, chemical-handling valve bodies, paper-mill suction box covers and equipment. 

Use Rayon manufacture, dietary supplement, animal feeds, mordant, wood preservative, analytical reagent. 

Use Rayon manufacture, agricultural sprays, chemical intermediate, dyestuffs, electroplating. 

There have been many attempts to utilize the approximately 1.8 V generated by the electrochemical reactions of the decomposer. Elowever, it has not been found possible to do this and to maintain high concentrations of sodium hydroxide and low residual sodium in the stripped mercury. The sodium hydroxide product obtained from the decomposer of a mercury cell is very pure, containing 0.001% or less sodium chloride. This product is referred to as rayon grade caustic because the high purity and low sodium chloride content makes it particularly suitable for rayon manufacture. This is achieved without the special purification steps required for the diaphragm cell product. 

Silk Rayon Manufacturers Association, University Tower, Montreal, Canada. A. Wesley Mason, president. ... 

World production of viscose rayon is estimated at 2.3 million tons [139]. The largest rayon manufacturers are American Viscose, American Enka, and Beaunit Mills. 

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