Phosgene construction materials

A further rapidly growing application for bisphenol A is the production of polycarbonates by reaction with phosgene. Polycarbonates are widely used as thermoplastic construction materials. 

Recent phosgene plants constructed in the Gulf Coast of the United States obtain their CO from synthesis gas by low-temperature fractionation [8]. Early units derived their raw material from coal, directly or indirectly. Most phosgene plants have their own caustic chlorine facilities. Since most phosgene is consumed captively, the hydrogen chloride is recovered in an oxidation unit. 

CO purity, 234 derivatives, 232 dimethyl carbonate, 252 membrane material of construction, 92 nonphosgene chemistry, 252-254 phosgene chemistry, 232-234 Scheiten-Baumann synthesis, 232, 233 transesterification, 233, 253, 254 Polyester fiber, 129, 132, 205 Polyester polyols, 229 Polyether polyols, 147, 148, 229 Polyethylene, 132, 183, 266 Polymerization ... 

Polycarbonates are well known to be typical amorphous polymers and to have excellent properties such as heat resistance, impact resistance, transparency, and dimensional stability (2-5). Polycarbonates, therefore, have been widely employed in various applications from nursing bottles to precision instruments (CDs, cameras, etc.), or in structural materials (for electrical applications, electronics, automobiles, construction applications, etc.). The global demand of polycarbonates has been growing more than 10% per year. The production capacity of polycarbonate world wide is about 1 million tons per year, and the boom in polycarbonate plant construction continues. Almost all of the polycarbonates, however, have been produced by the Phosgene Process . 

As many agrochemical intermediates, byproducts, and products are corrosive, toxic, flammable, and so forth, they require special materials of construction for a manufacturing plant. Some of the hardest-to-handle intermediates are routinely used in many manufacturing operations, including such materials as chlorine, bromine, hydrogen chloride, sodium, phosgene, phosphorus trichloride, phosphorus oxychloride, carbon disulfide, and many others. 

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