硫粉改性Mo基耐硫甲烷化催化剂

Mo-Based Catalyst Modified with Sulfur for Sulfur-Resistant Methanation

采用常规的H2S/H2混合气硫化方式和硫粉改性的硫化方式对15%(w)Mo/Al2O3和20%(w)Mo/25%(w)CeO2-Al2O3催化剂进行硫化处理,并考察了两种硫化方式处理的催化剂的耐硫甲烷化性能。实验结果表明,在600℃下,硫粉改性硫化处理的15%(w)Mo/Al2O3和20%(w)Mo/25%(w)CeO2-Al2O3催化剂上的CO转化率分别为60.3%和71.0%,而常规硫化方式处理的两种催化剂上的CO转化率仅为49.8%和61.2%,硫粉改性硫化的效果明显优于常规硫化。结合N2吸附-脱附、XRD、Raman光谱、XRF等表征手段对两种不同硫化方式处理的催化剂进行物相和结构分析的结果表明,两种硫化方式均能实现MoO3的完全转化,而硫粉改性的硫化方式可以促进Mo的硫化,提高n(S)∶n(Mo),使催化剂中出现晶态的MoS2。

15%（w）Mo/Al2O3 and 20%（w）Mo/25%（w）CeO2-Al2O3 catalysts were sulfurized by conventional sulfurization with a mixture of hydrogen sulfide and H2 or modification with sulfur powder. The activity of the catalysts for sulfur-resistant methanation was evaluated. The CO conversions at 600 ℃ on 15%（w）Mo/Al2O3 and 20%（w）Mo/25%（w）CeO2-Al2O3 catalysts modified with sulfur powder were 60.3% and 71.0%, while they were only 49.8% and 61.2% on the catalysts treaded by the conventional sulfurization, respectively. The sulfurization with sulfur powder improved the methanation activity of the catalysts. All the catalysts were characterized by means of N2 adsorption- desorption, XRD, Raman spectrum and XRF. It was found that both the sulfurization methods could make MoO3 completely transformed, and the sulfurization modification with sulfur powder increased n（S） ： n（Mo） and led to the appearance of MoS2 crystals.