Compositions comprising branched C.sub.10 mercaptans selected from the group consisting of 5-methyl-1-mercapto-nonane, 3-propyl-1-mercapto-heptane, 4-ethyl-1-mercapto-octane, 2-butyl-1-mercapto-hexane, 5-methyl-2-mercapto-nonane, 3-propyl-2-mercapto-heptane, 4-ethyl-2-mercapto-octane, 5-methyl-5-mercapto-nonane, and combinations thereof.

Compositions comprising branched C.sub.10 mercaptans selected from the group consisting of 5-methyl-1-mercapto-nonane, 3-propyl-1-mercapto-heptane, 4-ethyl-1-mercapto-octane, 2-butyl-1-mercapto-hexane, 5-methyl-2-mercapto-nonane, 3-propyl-2-mercapto-heptane, 4-ethyl-2-mercapto-octane, 5-methyl-5-mercapto-nonane, and combinations thereof.

The invention relates to a process for the co-production of methyl mercaptan and of dimethyl disulfide, comprising the following successive steps: a) reaction of at least one carbon oxide in the presence of hydrogen sulfide (H.sub.2S) and hydrogen to form a stream (M) comprising methyl mercaptan, water, and possibly unreacted hydrogen sulfide, b) purification of the stream (M) to obtain a stream (N) enriched in methyl mercaptan and a stream containing the uncondensable compounds (M.sub.uncond), c) optional recycling of the stream of uncondensable compounds (M.sub.uncond) obtained from step b) into step a), d) recovery of a first portion of the stream (N) including methyl mercaptan purified in step b), e) oxidation with sulfur of the second portion of the stream (N) of methyl mercaptan, to form a stream (O) comprising dimethyl disulfide, hydrogen sulfide, and possibly unreacted methyl mercaptan, f) purification of the stream (O) to separate, on the one hand, the enriched dimethyl disulfide and, on the other hand, the hydrogen sulfide and possibly the methyl mercaptan that has not reacted in step e), g) recycling of the hydrogen sulfide and possibly of the methyl mercaptan isolated in step f) into the stream (M) obtained from step a), h) recovery of the dimethyl disulfide isolated in step f).

The invention relates to a process for the co-production of methyl mercaptan and of dimethyl disulfide, comprising the following successive steps: a) reaction of at least one carbon oxide in the presence of hydrogen sulfide (H.sub.2S) and hydrogen to form a stream (M) comprising methyl mercaptan, water, and possibly unreacted hydrogen sulfide, b) purification of the stream (M) to obtain a stream (N) enriched in methyl mercaptan and a stream containing the uncondensable compounds (M.sub.uncond), c) optional recycling of the stream of uncondensable compounds (M.sub.uncond) obtained from step b) into step a), d) recovery of a first portion of the stream (N) including methyl mercaptan purified in step b), e) oxidation with sulfur of the second portion of the stream (N) of methyl mercaptan, to form a stream (O) comprising dimethyl disulfide, hydrogen sulfide, and possibly unreacted methyl mercaptan, f) purification of the stream (O) to separate, on the one hand, the enriched dimethyl disulfide and, on the other hand, the hydrogen sulfide and possibly the methyl mercaptan that has not reacted in step e), g) recycling of the hydrogen sulfide and possibly of the methyl mercaptan isolated in step f) into the stream (M) obtained from step a), h) recovery of the dimethyl disulfide isolated in step f).

The invention relates to a method for synthesising a mercaptan from a terminal olefin and hydrogen sulphide which comprises the following consecutive steps: Acatalytic addition of hydrogen sulphide to a terminal olefin catalysed by an acid catalyst; Bseparation of the products of the addition reaction into a light fraction including the surplus hydrogen sulphide and the olefins, and into a heavy fraction including at least one mercaptan and optionally one or more thioethers; Ca finishing step of passing the light fraction obtained in step B over an acid catalyst; then Dseparation of the products of the finishing step into a fraction that is rich in hydrogen sulphide and into a fraction that is rich in additives; and finally Erecirculation of the fraction that is rich in hydrogen sulphide to the catalytic addition step A. The invention also relates to the facility for implementing said method.

The invention relates to a method for synthesising a mercaptan from a terminal olefin and hydrogen sulphide which comprises the following consecutive steps: Acatalytic addition of hydrogen sulphide to a terminal olefin catalysed by an acid catalyst; Bseparation of the products of the addition reaction into a light fraction including the surplus hydrogen sulphide and the olefins, and into a heavy fraction including at least one mercaptan and optionally one or more thioethers; Ca finishing step of passing the light fraction obtained in step B over an acid catalyst; then Dseparation of the products of the finishing step into a fraction that is rich in hydrogen sulphide and into a fraction that is rich in additives; and finally Erecirculation of the fraction that is rich in hydrogen sulphide to the catalytic addition step A. The invention also relates to the facility for implementing said method.

The invention relates to a method for synthesising a mercaptan from a terminal olefin and hydrogen sulphide which comprises the following consecutive steps: Acatalytic addition of hydrogen sulphide to a terminal olefin catalysed by an acid catalyst; Bseparation of the products of the addition reaction into a light fraction including the surplus hydrogen sulphide and the olefins, and into a heavy fraction including at least one mercaptan and optionally one or more thioethers; Ca finishing step of passing the light fraction obtained in step B over an acid catalyst; then Dseparation of the products of the finishing step into a fraction that is rich in hydrogen sulphide and into a fraction that is rich in additives; and finally Erecirculation of the fraction that is rich in hydrogen sulphide to the catalytic addition step A. The invention also relates to the facility for implementing said method.

The present invention relates to a novel process for preparing sulfur-containing phenolic compounds, and to novel phenol derivatives substituted with at least one radical comprising a sulfur atom. Said sulfur-containing phenolic compounds are of use in numerous industrial fields, particularly the chemical industry, and said compounds are particularly suitable as, for example, antioxidant agents, UV stabilizers, heat stabilizers, and for other uses.

The present invention relates to a novel process for preparing sulfur-containing phenolic compounds, and to novel phenol derivatives substituted with at least one radical comprising a sulfur atom. Said sulfur-containing phenolic compounds are of use in numerous industrial fields, particularly the chemical industry, and said compounds are particularly suitable as, for example, antioxidant agents, UV stabilizers, heat stabilizers, and for other uses.