工业固定床Fe-Cu-K催化剂浆态床F-T合成适应性研究

Fundamental study of the reaction performance and stability of an industrial fixed-bed Fe-Cu-K catalyst was carried out by using a continuous stirred tank reactor (CSTR) equipped with a wax removal system under industrial relevant conditions: 255℃~290℃, 1.5MPa~3.1MPa total pressure, H2/CO (mol ratio)=0.50~1.52 and a space velocity of 1.0L /gcat·h－1~2.5L /gcat·h－1 (unreduced catalyst base) . The effects of reaction conditions on the catalyst activity, product selectivity and stability were investigated. The Scanning electron microscope (SEM) was used to investigate the catalyst attrition resistance. A 2 500 h slurry phase reaction result indicated that the changes of the process conditions (temperature, pressure, H2/CO feed ration and space velocity) had strong effects on the productivity and product selectivity. The effects of the adjustment of reaction pressure on the catalyst stability were particular obvious. The deactivation rates of the catalyst decreased with the changes of conditions in the following order: reaction pressure > space velocity > H2/CO feed ratios. The catalyst activity could be enhanced with the reaction temperature increasing, but the selectivity to heavy hydrocarbons was decreased. The increase of the reaction pressure could promote the conversion, and improve the heavy hydrocarbons selectivity and the hydrocarbon productivity. Increasing space velocity in feed gas could increase hydrocarbon productivity, and evidently decline the CO conversion and the selectivity of the heavy hydrocarbons. The increase of the H2/CO feed ratio could raise CO conversion and improve the selectivity of heavy hydrocarbons. The appropriate choice of the F-T reaction parameters in slurry phase could obtain the balance among catalyst activity, hydrocarbon distribution and productivity. The SEM results indicated that the catalyst exhibited robust attrition resistance.