溶胶-凝胶法制备非负载Ni-Mo复合氧化物加氢脱氧催化剂

Unsupported Ni-Mo Composite Oxide Catalysts Prepared by Sol-Gel Method for Hydrodeoxygenation

以柠檬酸为络合剂,采用溶胶-凝胶法制备了非负载型Ni-Mo复合氧化物催化剂,采用N2吸附-脱附、XRD、NH3-TPD等手段对催化剂进行了表征,以乙酸和苯酚为探针分子考察了nMo/nNi和反应温度对催化剂加氢脱氧性能的影响。结果表明,溶胶-凝胶法可制备较高比表面积的双介孔结构的Ni-Mo复合氧化物催化剂;催化剂组分主要以β-NiMoO4物相存在;在nMo/nNi为0～0.8时,催化剂的孔容、比表面积、中强酸强度及其加氢脱氧活性均随nMo/nNi的增加呈非单调的变化趋势。nMo/nNi为0.6时,催化剂的加氢脱氧活性最高,在0.3MPa、210℃条件下,苯酚的脱氧率达到99.9%;0.3MPa、270℃条件下,乙酸的脱氧率达到99.0%。

Unsupported Ni-Mo composite oxide catalysts were successfully prepared by sol-gel method with citric acid as a complex agent,and characterized by using N2 adsorption-desorption,X-ray diffraction（XRD） and temperature programmed desorption（NH3-TPD）.The effects of Mo/Ni molar ratio and reaction temperature on the hydrodeoxygenation activity of the catalysts were investigated emphatically with acetic acid and phenol as probe compounds.The results showed that the catalysts prepared by sol-gel method could possess higher specific surface area and the double mesoporous structure.The β-NiMoO4 phase detected by XRD was mainly in the catalysts.In the range of Mo/Ni molar ratio 0~0.8,the pore volume,the specific surface area,the middle strong acid strength and hydrodeoxygenation activity of the catalyst were non-monotonic with the increase of Mo/Ni ratio.The catalyst with Mo/Ni ratio 0.6 exhibited the highest hydrodeoxygenation activity.At 0.3 MPa and 210℃ the deoxygenation rate of the phenol and at 0.3 MPa and 270℃ the deoxygenation rate of acetic acid were 99.9% and 99.0%,respectively.