合成液体燃料的活性炭负载钴基催化剂的反应性能

在固定床等温积分反应器中,考察了活性炭负载钴基催化剂(Co/AC)的费托(F-T)合成反应性能,采用BET、H2-TPR和SEM等方法对Co/AC催化剂进行了表征。表征结果显示,Co/AC催化剂孔道属于微孔和中孔的混合结构,可用纯H2还原,还原温度选取350~400℃。实验结果表明,升高反应温度和反应压力、减小气态空速、增加原料气中H2与CO的摩尔比(H2/CO比),有利于提高CO的转化率;升高反应压力、降低反应温度、减小气态空速及原料气H2/CO比有利于高碳烃和高碳醇的生成。Co/AC催化剂用于F-T合成较优的工艺条件为:反应温度230℃,反应压力4.0M Pa,原料气H2/CO比2.00,气态空速2 000h-1。在该反应条件下,CO转化率为20.1%,CH4、低碳烃(C2~4)、高碳烃(C+5)、低碳醇(C1~5OH)及高碳醇(C+6OH)的选择性分别为19.1%,24.1%,36.5%,15.8%,4.5%。

Performance of Co/AC Catalyst in Synthesizing Liquid-Fuel

The performance of Co/activated carbon(AC) catalyst in Fischer-Tropsch synthesis was evaluated in a fixed-bed integral reactor.The result showed that high temperature,high pressure,high n(H2)∶n(CO) in syngas and low GHSV was beneficial to increase of the catalyst activity.The increase of pressure and the decreases of temperature,GHSV and n(H2)∶n(CO) would result in the increases of selectivities to hydrocarbons and alcohols with high carbon numbers.The Co/AC catalyst was characterized by means of BET,H2-TPR and SEM.The result showed that there were micropores and mesopores in the catalyst structure.The catalyst could be activated by H2 in the temperature range of 350-400 ℃.Under the optimum conditions of reaction temperature 230 ℃,reaction pressure 4.0 MPa,n(H2)∶n(CO) 2.00 and GHSV 2 000 h-1,the conversion of CO was 20.1%,and the selectivities to CH4,C2-4,C+5,C1-5OH and C+6OH were 19.1%,24.1%,36.5%,15.8% and 4.5%,respectively.