Abstrait

SYNTHESIS OF LIQUID HYDROCARBONS BY FISCHER�TROPSCH PROCESS USING INDUSTRIAL IRON CATALYST

Hanif A. Choudhury, Vijayanand S. Moholkar

Fischer–Tropsch process (F-T) is an efficient technology to synthesize liquid transportation fuel as well as other valuable chemicals. This process is associated with hydrogenation of carbon monoxide gas in presence of transition metal catalyst to valuable liquid transportation fuels and chemicals. F-T reaction is essentially a catalytic process, and most widely used catalysts are either iron or cobalt based catalysts. Iron catalysts are preferred when substiochimetric syngas (with H2/CO molar ration is less than 2, also known as producer gas) is chosen as feed stock for F-T reaction. The deficiency of H2 in substiochimetric syngas can be met by water-gas shift reaction (WGS). Normally, cobalt catalyst is WGS inactive, and hence, is chosen for F-T reaction when feed stock is synthesis gas (with H2/CO molar ratio of 2 or higher). In this work, we have studied the F-T process using an industrial iron catalyst for synthesizing liquid transportation fuels at different processing conditions or reaction parameters. A fixed bed reactor was fabricated indigenously. The physical properties of the catalyst were studied by XRD, BET and TPR study, whereas the liquid product obtained from the F-T reaction was analysed by a GC using FID detector. Carbon monoxide conversions were calculated by analysing the reactor effluent by a GC using TCD detector. The experiments reveal synthesis of liquid F-T fuel at 300oC and GHSV of 1800 h-1. The composition of synthesized liquid F-T fuel (in terms of carbon number of hydrocarbons) falls within the range of conventional diesel fuel