Arkema France

Ceca S.a.

Paul-Guillaume Schmitt

Georges Fremy

Francis Humblot

Jean-Luc Dubois

Serge Nicolas

Bernard Monguillon

Mélanie Vauthrin

Georges Frémy

Melanie Vauthrin

Gilles-olivier Gratien

A process for preparing an S,S′-dialkyldithiocarbonate from a dialkyl disulfide and from a particular metal catalyst, in the presence of carbon monoxide is described in addition to the use of S,S′-dialkyldithiocarbonates as reagents for the preparation of polycarbonates, compounds containing at least one urea and/or isocyanate function and compounds containing at least one thioalkyl function.

Process for preparing S,S′-dialkyldithiocarbonate from dialkyl disulfide

The invention relates to a solvent system for fluoropolymer comprising from 50 to 99.9% by weight of a composition (A) comprising dimethyl sulphoxide, and from 0.1 to 50% by weight of a composition (B) comprising at least one ketone. The invention also relates to the solutions comprising the said solvent system and the said fluoropolymer, and to their uses in the manufacture of films, membranes and coatings.

Solvents for fluoropolymers

The present invention relates to a sulphiding agent for a hydrotreating catalyst which makes possible faster sulphiding of the catalyst but which also makes possible to very significantly limit solid deposits, in particular of sulphur. The sulphiding agent according to the invention is essentially composed of diethyl disulphide (DEDS) or dipropyl disulphide(s) (DPDS) or dibutyl disulphide(s) (DBDS) and can be employed in 'in situ' and 'ex situ' presulphidation processes.

Hydrotreating catalyst sulphiding agent and its use for in situ and ex situ presulphidation

The invention relates to solvent compositions predominantly comprising at least one oxide of an organic sulfide, more particularly dimethyl sulfoxide, to which is added at least one odour-masking agent comprising at least one compound selected from monoesters, diesters or triesters, alcohols, ketones, aldehydes and terpenes.

Solvent composition based on an oxide of an organic sulfide with masked odour

The present invention concerns an additive for reducing the formation of coke and/or carbon monoxide in thermal hydrocarbon cracking units and/or of other organic compounds in heat exchangers. The additive according to the invention is essentially composed of diethyl disulphide (DEDS) or dipropyl disulphide(s) (DPDS) or dibutyl disulphide(s) (DBDS) and can be used on the metal walls of a cracking reactor and on the metal walls of a heat exchanger placed downstream from the cracking reactor, and during the process of cracking hydrocarbons and/or other organic compounds.

Additive for reducing coking and/or carbon monoxide in cracking reactors and heat exhangers and use of same

The present invention relates to a method for manufacturing nitric acid wherein a gaseous mixture, including air and ammonia, is transported on a catalyst including platinum to carry out catalytic oxidation of the ammonia, and is characterized in that a sulfurated component is added to the gaseous mixture.

Method for manufacturing nitric acid

The present invention relates to the masking of the odor of organic sulphides and more particularly that of alkyl sulphides or of dialkyl sulphides, especially dimethyl sulphide, and also of oxides thereof, and especially of dimethyl sulphoxide, by addition, to said organic sulphides, of at least one odor-masking agent comprising at least one monoester, at least one di- or triester, at least one alcohol, at least one ketone and, optionally, at least one terpene.

Organic-sulphide composition with masked odour

The present invention relates to a novel method of purifying a gas stream contaminated by CO, hydrocarbons and/or nitrogen oxides, in particular a gas stream based on air or a syngas, by adsorption on a bed of aggregated zeolitic adsorbent based on an LSX zeolite or LSX and X zeolites, of which at least 90% of the exchangeable cationic sites of the LSX zeolite or of the LSX/X zeolite blend are occupied by sodium ions, and the inert binder of which represents at most 5% of the weight of the adsorbent.

[object Object]

Zeolites of type A wherein all the cationic sites of which occupied by sodium, calcium and/or magnesium, potassium and hydronium cations, which exhibit the advantage of having a water adsorption capacity&gE;23%, which do not adsorb and therefore cannot desorb nitrogen, and which, incorporated in polyurethane (PU) resins, make it possible to increase the potlife of the PU formulations in which they are incorporated. Such zeolites are prepared by a process comprising bringing into contact an aqueous suspension of zeolite 3A, 4A or 5A, an aqueous solution of calcium or potassium salt(s) or solutions of calcium and potassium salt(s), and an acid solution, simultaneously or otherwise and in any order; and in then filtering off and washing the solid obtained, and then drying and activating the zeolite.

Growing community of inventors

Lescar, France

Paul-Guillaume Schmitt