Patent Law

Patent on Liquid Phase Hydrogenation of Alkynes

By Lawrence B. Ebert, Esq.

The patent in question US 7,408,091, is based on a continuation of the already-existing U.S. Pat. No. 7,045,670. Claim 1 recites:

A process for selective hydrogenation, comprising: preparing a reactant stream comprising an alkyne absorbed in a liquid absorbent; contacting the reactant stream with a selective hydrogenation catalyst in the presence of a gas stream comprising hydrogen and greater than 2000 ppm carbon monoxide, at hydrogenation conditions to provide a product stream; wherein the catalyst comprises a Group VIII metal; separating the absorbent from the product stream to recover a product.

The chemistry in question occurs in a relatively expensive "non-hydrocarbon" liquid:

The non-hydrocarbon liquid absorbent may comprise, without limitation: n-methyl-2-pyrrolidone (NMP), acetone, tetrahydrofuran (THF), dimethylsulfoxide (DMSO), monomethylamine (MMA), and/or combinations thereof, and is preferably NMP. The hydrogenation may preferably be effected by passing the absorbed acetylene and/or acetylenic compounds into the inlet of a fixed bed reactor, or a series of reactors, containing the catalyst, while co-currently passing a stream of gas containing at least hydrogen into the reactor at an inlet location.

The source of acetylene and/or acetylenic compounds and/or hydrogen and/or carbon monoxide may preferably be pyrolysis, thermal cracking, steam cracking, partial oxidation, or other like process, wherein hydrocarbons or hydrocarbon-containing streams are thermally and/or chemically modified to produce increased quantities of unsaturated components, and the acetylene and/or acetylenic compounds may comprise, but are not limited to: acetylene, allene, vinyl acetylene, methyl acetylene, ethyl acetylene, 1-butyne, 2-butyne, and 1,3-butadiyne.

Revolutionary?

Full post as published by IPBiz on August 23, 2008 (boomark / email).