COMPOUND METHOD FOR CATALYTIC PROCESSING OF NATURAL GAS TO OBTAIN LOWER OLEFINS Russian patent published in 2012 - IPC C07C11/04 C07C11/06 C07C1/26 C07C1/30 C07C19/03 C07C17/10 C07C17/154 

FIELD: chemistry.

SUBSTANCE: method involves oxidative chlorination of methane, pyrolysis of the methyl obtained from methane oxychlorination, and is characterised by that after extracting chloromethanes from the methane oxychlorination step, the remaining still liquor, which primarily contains methylene chloride and chloroform, undergoes hydrodechlorination at temperature 150°-300°C on a palladium or nickel-molybdenum catalyst on a support, and the obtained stream of reaction gas is split into two fractions. One of said fractions with high-boiling point hydrodechlorination products, which contain unreacted methylene chloride and chloroform, is fed into a chloromethane separation unit for the methane oxychlorination step, and the other fraction with low-boiling point gases from the chloromethane hydrodechlorination process, which contain hydrogen, methane, hydrogen chloride and partially methyl chloride, is merged with the gas stream coming from the methyl chloride pyrolysis step, followed by combined separation thereof into hydrogen, methane, lower olefins and unreacted methyl chloride, which is returned to the catalytic pyrolysis step.

EFFECT: use of present method enables to increase output of methyl chloride and, consequently, light olefins obtained during conversion thereof.

1 cl, 1 tbl, 2 ex, 2 dwg