Societe Nationale Elf Aquitaine (production)

Elf Aquitaine Production

Elf Acquitaine Exploration Production France

Elf Atochem S.a.

Elf Aquitaine Exploration Production France

Emmanuel F Arretz

Pierre Le Perchec

Marie Abiuso

Alfred Mirassou

Claude Landoussy

Patrick Auge

Jean Ollivier

Annie Commarieu

Michel Lacroix

Frederic Lopez

Emmanuel Cadot

Method for pre-sulphurization of catalysts

The process includes the reaction of a chloro-formamidinium chloride with a polystyrene-divinylbenzene resin functionalized with primary amine groups. The resins which can be obtained according to this process may in particular have a spacer arm of general formula (IV): ##STR1## with X representing oxygen or sulphur and m being equal to 1 or 2. This spacer arm bears at its end, on the right, a primary amine group or a guanidine group.

Process for the preparation of resins with a primary amine or guanidine

This process for the synthesis of 3-mercaptopropionic acid esters by addition reaction of H.sub.2 S to the corresponding acrylic acid ester is carried out in the presence of a solid-support functionalized with basic guanidine functional groups, on condition that these groups are free of hydrogen that is directly attached to a nitrogen atom.

Process for the synthesis of 3-mercaptopropionic acid esters

This process for the synthesis of 3-mercaptopropionic acid by an addition reaction of H.sub.2 S with acrylic acid is carried out in the presence of a solid support having basic guanidine functional groups, provided that the latter do not contain hydrogen bonded directly to a nitrogen atom.

Process for the synthesis of 3-mercaptopropionic acid

The process includes the reaction of a chloroformamidinium chloride with a polystyrene-divinylbenzene resin functionalized with primary amine groups. The resins which can be obtained according to this process may in particular have a spacer arm of general formula (IV):

Resins with a primary amine or guanidine function

The preparation of organic disulphides and polysulphides by reaction of sulphur with a mercaptan or with a polysulphide of lower sulphur order in order to convert it into polysulphide of higher order, or alternatively by reaction of a mercaptan with an organic polysulphide of high sulphur order in order to convert it into polysulphide of lower sulphur order, in the presence of a catalyst in the form of a resin with a basic function, characterized in that the resin is based on polystyrene-divinylbenzene (PS-DVB) functionalized with primary amino groups and having the general formula (I): ##STR1## being the PS-DVB resin support, L being a linear organic radical which is as long as or longer than the methylene radical (--CH.sub.2 --).

Process for the preparation of organic disulphides and polysulphides in

In a process for the preparation of organic disulphides and polysulphides by reaction of sulphur with a mercaptan or with a polysulphide of lower sulphur order in order to convert it into polysulphide of higher order, or alternatively by reaction of a mercaptan with an organic polysulphide of a high sulphur order in order to convert it into a polysulphide of lower sulphur order, in the presence of a catalyst in the form of a resin with a basic function, the resin is based on a polystyrene-divinyl benzene support functionalized with guanidine or amidine groups, and the reaction is preferably conducted in the presence of methanol.

The invention relates to the manufacture of methyl mercaptan by catalytic hydrogenation of dimethyl disulphide on a catalyst based on sulphide(s) of at least one transition metal. The selectivity with respect to methyl mercaptan is considerably improved by working in the presence of water and/or hydrogen sulphide.

Synthesis of methyl mercaptan from dimethyl disulphide

The invention relates to the manufacture of dimethyl disulphide from methyl mercaptan and sulphur. The process according to the invention is characterized in that it comprises:

Process for the manufacture of dimethyl disulphide

The invention relates to the preparation of organic disulphides and polysulphides by the action of sulphur on a mercaptan or on a polysulphide which is lower in sulphur, in the presence of a basic catalyst. In the process according to the invention, an anion exchange resin is used as catalyst.

Process for the preparation of organic disulphides and polysulphides

This invention relates to improvement to a process for the preparation of mercaptoalcohols containing, more particularly, up to 24 carbon atoms and, preferably, more than 3 carbon atoms, by reaction of the corresponding vicinal epoxides with hydrogen sulphide. The process comprises incorporating into the reaction mixture a catalyst comprising a guanidine and/or of organic derivatives of a guanidine, and/or of guanidine salts, in particular of guanidine salts. The catalyst can be either in liquid and/or solid form, depending on the nature of the catalyst and its solubility in the reaction mixture, or fixed and/or impregnated into various solid materials. The materials can be organic in nature such as neutral and/or basic polymer resins, polymers or copolymers, or can be inorganic in nature such as alumninas, silicas, aluminosilicates, zeolites, active charcoals, oxides and/or metal salts. This process enables mercaptoalcohols to be obtained in a high overall yield while permitting relatively short reaction times.

Process for the preparation of mercaptoalcohols

The invention relates to the synthesis of dithiols and more particularly that of .alpha.,.omega.-dithiols having 5 to 20 carbon atoms. The process according to the invention comprises reacting a di-(tertiary-alkylthio)alkane with hydrogen sulphide in the presence of a solid acid catalyst. The alkane dithiol is obtained selectively and a tertiary-alkyl mercaptan is obtained as by-product. It is possible to reuse the latter in a cyclical process to produce the original di-(tertiary-alkylthio)alkane.

Process for preparation of dithiols

A catalytic process for the production of mercaptans from thioethers, which comprises reacting a thioether, in which the sulfur atom of the thioether function is bonded, on the one hand to a tertiary carbon atom and, on the other hand, to a primary or secondary carbon atom, with hydrogen sulfide in the presence of an appropriate acid catalyst, especially an aluminosilicate or an ion-exchange resin.

Catalytic process for the production of mercaptans from thioethers

The invention relates to the synthesis of tertiary mercaptans from isobutylene homopolymers and from hydrogen sulphide by means of heterogeneous catalysis. In the processs according to the invention, the reaction is carried out at a temperature below 45.degree. C., preferably between 0.degree. and 35.degree. C., in the presence of a catalyst consisting of a dry cation exchange resin. Excellent yields of tertiary mercaptan are thus obtained, while the formation of undesirable byproducts is virtually avoided.

Growing community of inventors

Pau, France

Emmanuel F Arretz