Fischer-Tropsch process

A process for conducting a Fischer-Tropsch reaction, comprising:

• flowing a reactant mixture in a microchannel reactor in contact with a catalyst to form a product comprising at least one higher molecular weight hydrocarbon product, the microchannel reactor comprising at least one process microchannel and at least one heat exchange channel in thermal contact with the at least one process microchannel, the catalyst being in the at least one process microchannel, the at least one heat exchange channel having a heat exchange fluid in it for exchanging heat with the at least one process microchannel;
• the catalyst being derived from a catalyst precursor comprising cobalt or a cobalt oxide and a surface modified support wherein the surface of the support is modified by being treated with titania, zirconia, magnesia, chromia, alumina, or a mixture of two or more thereof, the catalyst precursor comprising from about 35% to about 50% by weight cobalt based on the weight of the metal as a percentage of the total weight of the catalyst precursor;
• wherein the product further comprises tail gas, at least part of the tail gas being separated from the higher molecular weight hydrocarbon product and combined with fresh synthesis gas to form the reactant mixture, the volumetric ratio of the fresh synthesis gas to the tail gas in the reactant mixture being in the range from about 1:1 to about 10:1;
• the reactant mixture comprising H2 and CO, the mole ratio of H2 to CO in the reactant mixture based on the concentration of CO in the fresh synthesis gas being in the range from about 1.4:1 to about 2.1:1;
• wherein the conversion of CO from the fresh synthesis gas in the reactant mixture is at least about 70%;
• and
• the selectivity to methane in the product is in the range from about 0.01 to 10%.