METHOD OF PRODUCING CRYSTALLINE SODIUM DIMETHYL DITHIOCARBAMATE Russian patent published in 2005 - IPC

FIELD: industrial inorganic synthesis.

SUBSTANCE: invention relates to methods for production of crystalline sodium dimethyl dithiocarbamate widely used in industry, in particular as rubber vulcanization accelerator, in manufacture of cables, other dithiocarbamates and thiurams, and as flotation reagents in concentration of nonferrous metal ores. Crystalline sodium dimethyl dithiocarbamate is obtained by condensation of carbon disulfide, dimethylamine, and sodium hydroxide in a solvent (toluene) medium followed by crystallization and filtration. More specifically, dimethylamine is added in the form of 42-44% aqueous solution to reaction mixture cooled to 2-5%, which contains toluene, carbon disulfide, and 40-45% sodium hydroxide aqueous solution at molar ratio 1:1:1.0.3, respectively. Resulting reaction mass is kept ay 10-30°C until water-toluene suspension of dimethyl dithiocarbamate is formed. Before crystallization, water is azeotropically distilled away at 75-90°C, and crystallization is effected at 0-5°C. Sodium dimethyl dithiocarbamate is obtained in the form of crystalline scales with 78% main substance. Product does not conglomerate, well transported, and can be stored for a long time without loss in its consumer's properties.

EFFECT: optimized production process and improved properties of product.

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