Preparation and use of supported potassium (or rubidium)-Group VIII-metal cluster catalysts in CO/H.sub.2 Fischer-Tropsch synthesis reactions

摘要

This invention relates to unique supported potassium (or rubidium) - Group VIII-metal cluster catalysts which are useful in CO/H. sub.2 reactions (Fischer-Tropsch synthesis reactions). The novel catalysts of the instant invention are prepared by depositing well characterized potassium (or rubidium) - Group VIII-metal carbonyl cluster complexes onto high surface area supports. Following a subsequent reduction, the precursor bimetallic cluster complexes are decomposed on the support surface forming a potassium (or rubidium) promoted Group VIII- metal cluster catalyst in which the potassium (or rubidium) and Group VIII metals are intimately associated. These unique, highly promoted cluster catalysts have been found to demonstrate high Group VIII-metal dispersions and enhanced Fischer-Tropsch activities and selectivities for producing olefinic and paraffinic hydrocarbons. In addition methane formation is dramatically reduced over the supported bimetallic cluster catalysts of the instant invention when compared to conventionally prepared supported potassium (or rubidium) promoted Group VIII-metal catalysts.