原位XRD反应装置下H2O对Fe5C2的物相及F-T反应性能影响的研究

In situ XRD study of the effect of H2O on Fe5C2 phase and Fischer-Tropsch performance

将原位XRD反应装置与在线气相色谱技术结合,研究了不同H 2O含量(4.36%、1.68%、0.56%)条件下单一相Fe 5C 2的氧化速率,并考察了不同Fe 5C 2氧化程度(0、25%、55%、68%)和氧化次数对其费托合成(F-T)反应性能的影响。研究结果表明,Fe 5C 2物相的氧化速率随H 2O含量的提高而逐渐增加,同时H 2O氧化使Fe 5C 2颗粒粒径减小,暴露出更多活性位点,造成F-T反应活性提高,且氧化程度越大,活性提高越明显;随着氧化次数的增加,F-T反应活性逐渐提高,但CH 4选择性增加,C 5+选择性逐渐降低。

In situ XRD reaction device combined with the online gas chromatography was used to study the oxidation behavior of the effect of H 2O content(4.36%,1.68%,0.56%)on the phase and Fischer-Tropsch synthesis(FTS)performance of the single phase Fe 5C 2.The results show that the oxidation rate of the Fe 5C 2 phase increases with the increase of the content of injected H 2O.Meanwhile,the particle size of Fe 5C 2 phase decreases and more active sites exposes during the H 2O oxidation,resulting in the increase of the FTS activity.Furthermore,the FTS activity increases with the increase of the oxidation times,but the selectivity of CH 4 increases and the C 5+selectivity decreases gradually.