US 12,227,468 B2
Process for the co-production of methyl mercaptan and of dimethyl disulfide from carbon oxides
Georges Fremy, Lacq (FR); Jean-Michel Raymond, Cauneille (FR); Eric Lamant, Lacq (FR); and Helori Salembier, Lacq (FR)
Assigned to Arkema France, Colombes (FR)
Filed by Arkema France, Colombes (FR)
Filed on May 10, 2022, as Appl. No. 17/740,839.
Claims priority of application No. 2104979 (FR), filed on May 11, 2021.
Prior Publication US 2022/0363630 A1, Nov. 17, 2022
This patent is subject to a terminal disclaimer.
Int. Cl. C07C 319/02 (2006.01); C07C 319/06 (2006.01); C07C 319/16 (2006.01); C07C 319/24 (2006.01); C07C 319/28 (2006.01)
CPC C07C 319/02 (2013.01) [C07C 319/06 (2013.01); C07C 319/16 (2013.01); C07C 319/24 (2013.01); C07C 319/28 (2013.01)] 11 Claims
OG exemplary drawing
 
1. A process for the co-production of methyl mercaptan and of dimethyl disulfide, comprising the following successive steps:
a) reacting at least one carbon oxide in the presence of hydrogen sulfide (H2S) and hydrogen to form a stream (M) comprising methyl mercaptan, water, and optionally unreacted hydrogen sulfide,
b) purifying the stream (M) to obtain a stream (N) enriched in methyl mercaptan and a stream containing uncondensable compounds (Muncond),
c) optional recycling the stream of uncondensable compounds (Muncond) obtained from step b) into step a),
d) recovering a first portion of the stream (N) including methyl mercaptan purified in step b),
e) oxidizing with sulfur a second portion of the stream (N) of methyl mercaptan, to form a stream (O) comprising dimethyl disulfide, hydrogen sulfide, and optionally unreacted methyl mercaptan,
f) purifying the stream (O) to separate the dimethyl disulfide from the hydrogen sulfide and optionally the methyl mercaptan that has not reacted in step e),
g) recycling the hydrogen sulfide and possibly the methyl mercaptan isolated in step f) into the stream (M) obtained from step a),
h) recovering the dimethyl disulfide isolated in step f).