甲烷在褐煤煤焦上的裂解反应研究

采用石英管固定床反应器，分别考察了不同温度（1123K、1173K、1223K、1273K）及不同浓度（10%、15%、20%）下，甲烷在褐煤煤焦上的裂解反应。结果表明,褐煤煤焦对甲烷裂解反应具有良好的催化活性，在所考察温度范围内，甲烷的初始转化率最高达99.5%，温度越高，甲烷的初始转化率越高；但随着反应的进行，转化率逐渐降低；甲烷进气浓度越高，初始转化率越低，而且催化剂失活也越快。反应前后煤焦电镜扫描照片及物性参数的比较表明，甲烷裂解生成炭沉积在煤焦表面，导致煤焦比表面积随反应的进行逐渐降低，与甲烷裂解转化率的变化趋势一致；反应后煤焦的孔容及微孔容都有所降低，平均孔径增大，说明甲烷的裂解生成炭造成了煤焦孔道尤其是微孔的堵塞，比表面积减小，导致了甲烷的转化率降低。

Methane cracking over lignite char

Methane cracking over a lignite char was studied in a fixed bed reactor. The experiments were performed at temperature range from 1 123 K to 1 273 K and atmospheric pressure. The total flow rate was 250 mL/min with methane concentrations of 10%, 15% and 20%, respectively. The lignite char shows a significant catalytic activity on methane cracking. The maximum conversion of methane of 99.5% is achieved at 1 273 K in the initial stage. However, the methane conversion decreases with reaction time due to deacti...