US 11,897,837 B2
Process for the co-production of alkyl mercaptan and dialkyl disulfide from alcohol
Georges Fremy, Lacq (FR); Jean-Michel Raymond, Cauneille (FR); and Eric Lamant, Lacq (FR)
Assigned to Arkema France, Colombes (FR)
Filed by Arkema France, Colombes (FR)
Filed on May 10, 2022, as Appl. No. 17/740,655.
Claims priority of application No. 2104977 (FR), filed on May 11, 2021.
Prior Publication US 2022/0363631 A1, Nov. 17, 2022
Int. Cl. C07C 319/24 (2006.01); C07C 319/28 (2006.01); C07C 319/08 (2006.01)
CPC C07C 319/24 (2013.01) [C07C 319/08 (2013.01); C07C 319/28 (2013.01)] 10 Claims
OG exemplary drawing
 
1. Process for the co-production of alkyl mercaptan and of dialkyl disulfide, comprising the following successive steps:
a) reaction of a C1-C4 alcohol in the presence of hydrogen sulfide (H2S) to form a stream (M) comprising an alkyl mercaptan, water, and optionally unreacted hydrogen sulfide,
b) purification of the stream (M) to obtain a stream (N) enriched in alkyl mercaptan,
c) recovery of a first portion of the stream (N) including the alkyl mercaptan purified in step b),
d) oxidation with sulfur of the second portion of the stream (N) of alkyl mercaptan, to form a stream (O) comprising a dialkyl disulfide, hydrogen sulfide, and optionally unreacted alkyl mercaptan,
e) purification of the stream (O) to separate, on the one hand, an enriched dialkyl disulfide and, on the other hand, the hydrogen sulfide and optionally the alkyl mercaptan that has not reacted in step d),
f) recycling of the hydrogen sulfide and optionally of the alkyl mercaptan isolated in step e) into the stream (M) obtained from step a),
g) recovery of the dialkyl disulfide isolated in step e).