Processing solvents for

Approximately 50% of the demand for tetrachloroethylene is in the dry-cleaning industry where about 80% of all dry cleaners use it as their primary cleaning agent. Use as a feedstock for chlorofluorocarbon production accounts for 30% of current demand. Metal cleaning and miscellaneous appHcations represent 12 and 8% of demand, respectively. The miscellaneous appHcations include such varied uses as transformer insulating fluid, chemical maskant formulations, and as a process solvent for desulfurizing coal. 

Uses. Process solvent for extractions of aromatics and for purification of acid gases... 

Prior to their current phase-out, chlorofluorocarbons (CFCs) were widely used as processing solvents for various materials. CFCs were well suited for many medical applications owing to their high solvency, nonflammability, good materials compatibility, and low toxicity. The uses for CFCs include a silicone deposition solvent, a fluoropolymer dispersion liquid, and processing solvents. However, the Montreal Protocol phase-out of ozone-depleting substances has required that alternative dispersants and solvents be found. Limitations of most available alternatives include flammability, low volatility, poor solvency, and poor materials compatibility. 

Romanovskiy, V.N., Smirnov, I.V., Babain, V.A. et al. 2001. The universal solvent extraction (UNEX) process. I. Development of the UNEX process solvent for the separation of cesium, strontium, and the actinides from acidic radioactive waste. Solvent Extr. Ion Exch. 19 (1) 1-21. 

To minimize waste streams, ancillary processes not shown in Figure 2 may be used to treat used process solvents for recycle. 

Monochlorobenzene and 1,2-dichlorobenzene are both colorless, flammable hquids with a sweet, penetrating odor. These are soluble in benzene and alcohols, but are insoluble in water. The vapors are heavier than air and may travel a considerable distance from the source of evaporation. Ignition and flashback to the source may lead to a fire, releasing in toxic and corrosive gases. Monochlorobenzene is a process solvent for methylene diisocyanate, the latter being used as a solvent in adhesives, polishes, waxes, pharmaceutical products, and natural rubber. 

Chem. Descrip. Propylene glycol monomethyl ether acetate CAS 108-65-6 EINECS/ELINCS 2( 03-9 Uses Retarder, solvent for gravure inks, lacquers, thinners, baking enamels solvent for screen inks, cosmetics, food-contact applies., coating polymers (CAB, NC, epoxy, acrylic copolymers, phenoxy resins), cleaning fluids, automotive paints process solvent for resin mtg., urethanes Features Slow evaporating... 

Chem. Descrip. N-Methyl pyrrolidone CAS 872-50-4 EINECS/ELINCS 212-828-1 Uses Solvent, cosolvent In coatings, stripping/cleaning of paints/vamishes. Industrial cleaning, mold cleaning, petrochem. processing solvent for adhesives, inks, dyes, soaps, metal complexes, agric. solvent for PVAc, PVDF, PS, vinyl copolymers, nylon and aromatic polyamides and polyimides, polyesters, acrylics, PC, cellulose derivs., syn. elastomers, waxes... 

Uses Dispersant for lubricants, mold release agents, protective coatings reaction media for polymerizations, purification, separation processes solvent for removal of halogenated lubricants, oils, greases carrier for halogenated material zero ozone depletion potential Manuf./Distrib. Aldrich Fluka Miteni SpA Trade Names PF-5070... 

Uses Lubricant for two-stroke cycle engines, rubber, greases, textiles reactive intermediate for resins, plasticizers, surfactants antifoam in boiler water, latex processing solvent for inks and dyes insect repellent antistat, skin conditioner in cosmetics Manuf./Distrib. Aldrich Trade Names Ucon LB-65... 

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