ExxonMobil hydroformylation

The hydroformylation of 1-hexene by supported ionic liquid catalysis (SILC) was recently reported by researchers at ExxonMobil. In this system, the active catalyst HRh(CO)(tppti)3 (tppti = tri(m-sulfonyl)triphenyl phosphine tris(l-butyl-3-methyl-imidazolium)) is contained within the ionic liquid phase while excess tppti ligand is immobilized in the support material. TOP values of 65 min" were obtained with silc while an unsupported biphasic ionic liquid medium gave TOP values of 23 min. ... 

This concept was first applied for hydroformylation in 2002 by Mehnert at ExxonMobil [50]. This work involves a surface of a support material (silica gel) that is modified with a monolayer of covalently anchored fragments of l-n-butyl-3-[3-(triethoxysilanyl)propyl]imidazolium. Treatment of this surface with additional IL results in the formation of a multiple layer of free ionic liquid which serves as... 

Acknowledgments This research has been supported over the years by NSF, the Louisiana Board of Regents through their Industrial Ties programs, and the following companies Hoechst Celanese, Arco Chemical, Albemarle, Ferro, Eastman Chemical, Sasol North America, and current funding from Dow Chemical. Additionally, the team leader had excellent discussions and interactions with hydroformylation experts at Union Carbide (now Dow), ExxonMobil, and Shell Chemical. 

ExxonMobil Biphasic carbonylation catalysis using conventional rhodium catalysts in Lewis-acidic ionic liquids, the electrochemical oxidation of sulfur compounds in naphtha, the use of supported ionic liquids, catalytic hydroformylation, hydrogenations, aldol condensations, and even ionic liquid synthesis... 

In catalyst recovery, only marginal improvements to the previous state of the art are described in the patents published by ExxonMobil. Some general aspects are presented here to illustrate this quite complicated part of the commercial hydroformylation process with cobalt. The catalyst, which is either already in the olefin feed to the reactor or is fed to the reactor as fresh catalyst, for example, in the form of dicobalt octacarbonyl Co2(CO)g or cobalt salt, or many other compounds, has to be removed from the reaction mass after the reaction. One... 

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