Synthesis gas (CO and H_2) obtained from coal, natural gas biomass can be converted into paraffins and olefins via Fischer-Tropsch process, mainly aiming at the production of diesel fuel. The diesel fuel is composed of hydrocarbons with the carbon number of ca. 10-20. Hydrocarbons with carbon number less than 10, which are inevitably produced in Fischer-Tropsch synthesis and usually rich in olefins, are useless as fuel if they can not be converted to other chemical structures. The hydroformylation process provides an effective way to make good use of the produced olefins. Hydroformylation, the synthesis of aldehyde and alcohol from olefins and synthesis gas, is a well-known homogeneous cobalt-catalyzed reaction. In order to keep the carbonyl intermediate (active species) stable, the high operation pressure of syn-gas (about 10-20 MPa) must be applied to the system. However this will result in the extra economic investment for the high-pressure reactor, compressor and other systems. Moreover, the drawbacks of homogenous catalysis, such as the recovery of catalyst metal and the separation problem of catalyst and products, retard the practical application in the wide fields. Therefore, considerable effects have been devoted to the study on the heterogeneous process for hydroformylation, most of which have been carried out on the supported rhodium and cobalt catalysts.
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