分别以A120,-Si02,A1203-Ti02,TiO2-Si02和Ti02-Zr02双金属氧化物为载体研究Ni基催化剂的愈创木酚加氢脱氧性能.重点考察了催化剂载体、溶剂种类、反应温度和压力对愈创木酚转化率及产物选择性的影响,并对催化剂的抗积碳性能、重复利用性能和愈创木酚加氢脱氧反应机理进行了探讨.通过BET(Brunauer—Emmett—Teller)比表面积、x射线衍射(XRD)、NH3程序升温脱附(NH3-TPD)和H2程序升温还原(H2-TPR)等表征手段对催化剂的比表面积、物相结构、表面酸性、可还原性能进行了表征.结果表明,Ni/TiO2-ZrO2催化性能相对较优.在300℃、初始氢压4MPa、以十氢萘为溶剂的最佳反应条件下,愈创木酚的转化率为100%,环己烷选择性高达86.4%.该催化剂还具有抗积碳性能,反应后的催化剂上仅检测到3.2%(质量分数)的积碳量.
Using bimetal mixed oxides A1E 03 -SiO2, A12 03-TIO2 , TiO2-SiO2 and TiO2-ZrO2 as supports, nickel catalysts were tested through hydrodeoxygenation (HDO) reaction of guaiacol and characterized by Brunauer- Emmett-Teller( BET), X-ray diffraction(XRD), NH3 temperature programme desorption( NH3-TPD) and n2 temperature programme reduction (HE-TPR) techniques. The effects of support, solvent, reaction temperature and pressure on conversion of guaiacol and selectivity of different products were studied. The resistance of coke, recyclability of catalyst and the reaction mechanism for guaiacol hydrodeoxygenation were also dis- cussed. The results show that the activities of Ni/TiO2-ZrO2 are obviously better than the others under the same reaction conditions. The conversion of guaiacol over Ni/TiO2-ZrO2 catalyst is 100% and the selectivity for cyclohexane is as high as 86.4% under the optimization condition of 300 ~C and the initial H2 pressure of 4 MPa in decalin. Moreover, the Ni/TiO2-ZrO2catalyst has a better performance of anti-coking than traditional catalysts, about only 3.2% (mass fraction) of residual cokes on the catalyst surface.