Phosgene downstream products

Phosgene; Carbonic dichloride; Carbonyl chloride; Chloro-formyl; Chloroformyl chloride. Molecular formula: CCl2O; Molecular weight: 98.92; CAS number: 75-44-5. Properties: Colorless to pale yellow liquid or easily liquefiable gas. When concentrated, it has a strongly irritating or suffocating odor. Melting point: -127.84°C (-118°C), boiling point: 7.48°C (8.2°C), relative density: 1.381 (20/4°C). Easy to liquefy. It is soluble in benzene, toluene, carbon tetrachloride, acetic acid, and chloroform, slightly soluble in water, and gradually hydrolyzes. Non-flammable. Preparation method: When a small amount of phosgene is required, carbon tetrachloride can be reacted with sulfuric acid. Heat carbon tetrachloride to 55–60°C and add fuming sulfuric acid drop by drop; phosgene will then be released. If liquid phosgene is desired, the phosgene generated is condensed. Phosgene is typically produced industrially by the reaction of carbon monoxide with chlorine. This is a highly exothermic reaction; the reactor equipped with activated carbon should have a water-cooled jacket to maintain the reaction temperature at around 200°C. To obtain high-quality phosgene and reduce equipment corrosion, an appropriate excess of thoroughly dried carbon monoxide should be used when mixing it with chlorine. The mixture is fed from the upper part of the synthesizer; after passing through the activated carbon layer, it is quickly converted into phosgene. When a synthesizer with specifications of Ф700×2900 is used, each unit can produce 200 tons of phosgene per year. Raw material consumption quotas: chlorine (>99%) 925 kg/t, oxygen (under standard conditions) 268 (m3) kg/t, coke 400 kg/t. Uses: Phosgene is an important organic intermediate with numerous applications in pesticides, pharmaceuticals, engineering plastics, polyurethane materials, and **. In pesticide production, it is used to synthesize various carbamate insecticides such as sevin, carbofuran, and fenitrothion, as well as fungicides like carbendazim and various herbicides. China’s Linxiang Amino Chemicals Factory and Ningyang Pesticide Factory have become manufacturing hubs for carbamate pesticides, with the Ningyang Pesticide Factory being able to produce 43 different varieties. Isocyanate-based products produced from phosgene, such as TDI, MDI, and PAPI, are important raw materials for rigid polyurethane foams, soft polyurethane foams, elastomers, and synthetic leather ； Certain types of isocyanates are widely used in polyurethane coatings ； There are also special varieties used as adhesives, such as Lenka glue. It is used in the dye industry to produce dye intermediates such as alizarin acid, and in the defense industry to produce the fixing agent dimethyldiphenylurea as well as as a military poison gas. Chloroformates produced using phosgene are intermediates in organic synthesis for pesticides, pharmaceuticals, polymer initiators, and more. When producing the engineering plastic polycarbonate via the phosgene direct method or the transesterification method, phosgene is required as a raw material.

AKD alkylene diolefin dimer......