摘要
制备了一系列NiM/γ-Al2O3(M=Fe,Mo)负载型催化剂,通过BET、TPR、XRD、XPS、H2-TPD和NH3-TPD等对催化剂的物化性质进行了表征.并以乙酸为模型化合物,研究了Fe、Mo助剂对C—C键和C—O键的断裂、加氢脱氧活性和产物选择性的影响.结果表明:Fe、Mo助剂的加入可促进NiO的还原,提高NiO的分散度及表面NiO的含量,因而使催化剂的活性提高,乙酸转化率可达95%以上;Ni/γ-Al2O3催化剂在低温下有利于乙酸乙酯的生成,提高温度有利于C—C键的断裂,生成甲烷;加入Fe或Mo可增强催化剂的加氢性能,活化C—O键并部分抑制C—C键的断裂;在产物选择性上,Fe助剂有利于生成乙醇,而Mo助剂增强了催化剂酸性,有利于生成乙烷.
A series of supported NiM/γ-Al2O3（M= Fe,Mo） catalysts was prepared and characterized by nitrogen physisorption,H2 temperature-programmed reduction（TPR）,X-ray diffraction（XRD）,X-ray photoelectron spectroscopy（XPS）,and H2 or NH3 temperature-programmed desorption（H2-TPD or NH3-TPD） techniques.The catalytic performances of the catalysts in the hydrodeoxygenation of acetic acid were systematically investigated in a fixed-bed reactor.The dispersion and reduction of NiO in Ni/γ-Al2O3 catalyst was remarkably improved by addition of Mo or Fe,which may lead to a high catalytic activity.Over Ni/γ-Al2O3 catalyst,the formation of acetic ester was favoured at low temperature,while the domain product was methane resulting from the C—C bond dissociation at high temperature.The C—C bond dissociation capability of Ni/γ-Al2O3 catalyst was suppressed by addition of Fe,and a high yield of ethanol was observed over at Ni-Fe/γ-Al2O3 catalyst and low temperature.A higher yield of ethane was obtained over Ni-Mo/γ-Al2O3 catalyst as the surface acidity of the catalyst was improved by addition of Mo.
出处
《分子催化》
EI
CAS
CSCD
北大核心
2011年第1期30-36,共7页
Journal of Molecular Catalysis(China)
关键词
镍基催化剂
乙酸
费托合成油品
生物质油
加氢脱氧
Ni-based catalyst
acetic acid
Fischer-Tropsch syncrude
bio-oil
hydrodeoxygenation
