The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 12, 2001
Filed:
Aug. 11, 2000
Jean-Jacques Charrin, Lyons, FR;
Pascale Colin, Chassieu, FR;
Raphael Guinamard, La Mulatiere, FR;
Françoise Igersheim, Lyons, FR;
Gilbert Margeriat, Ville Sous Anjou, FR;
Rhodia Chimie, Boulogne Billancourt, FR;
Abstract
The invention concerns a method for obtaining alkylmonohydrogenohalogenosilanes (AHHS), for example Me,HSiCl.Said AHHS are prepared by redistribution from MeHSiCl,and Me,HSiCl in the presence of a catalyst such as AlCl,, which can start a parasitic disproportionation which affects the AHHS produced. In order to avoid this, the method consists in using an inhibitor which neutralizes AlCl,after redistribution, The problem which still prevails and on which the present invention is based is related to the fact that during distillation, which aims at separating the required AHHS, the latter are again subjected to the parasitic disproportionation. In order to solve this problem, the invention proposes a method for preparing AHHS comprising steps (a) of redistribution, (b) use of an inhibitor of AlCl,and (c) separating and collecting by distillation AHHS formed in the raw reaction mixture of redistribution using three distillation columns I, II,III and proceeding in such a way that, at least in one part of the distillation circuit, the AHHS aimed at are in the presence of the AlCl,inhibitor. Advantageously, the inhibitor is injected in the reflux of column I top. The invention also concerns a train of three distillation columns comprising means of injecting the AlCl,inhibitor.