FIELD: chemistry.
SUBSTANCE: invention relates to a method of producing dimethyl oxalate, involving the following steps: step a): supplying to a reactor a combination of a reaction material containing carbon monoxide and methyl nitrite, which reacts in the presence of a platinum group metal catalyst to form a gas-phase stream containing dimethyl oxalate; and step b): feeding a gas-phase stream containing dimethyl oxalate into the dimethyl oxalate separation column and providing countercurrent contact of the gas-phase flow containing dimethyl oxalate with a stream containing methanol fed into the extraction column in its upper part, to obtain crude methanol in an upper part of the column and a dimethyl oxalate product in the lower part of the column, wherein the gas stream containing dimethyl oxalate is not cooled before feeding to the dimethyl oxalate extraction column; gas-phase flow containing dimethyl oxalate is not passed through the alcohol flushing column before its supply to the dimethyl oxalate extraction column; wherein the reaction material contains 5–40 mol. % carbon monoxide 5–30 mol. % methylnitrite, 1–10 mol. % nitrogen monoxide 0.1–10 mol. % of methanol and inert gases which make up the rest; wherein the dimethyl oxalate extraction column comprises an absorption and rectification section and a stripping section and a ratio of the height of the absorption and rectification section to the stripping section ranges from 0.2:1 to 5:1. Additionally described is a method of producing of dimethyl oxalate and dimethylcarbonate as a by-product.
EFFECT: said methods are characterized by simplicity of process steps, low energy consumption, high output of dimethyl oxalate, and so forth.
15 cl, 3 dwg, 7 tbl, 9 ex
