An efficient NixZryO catalyst for hydrogenation of bio-derived methyl levulinate to gamma-valerolactone in water under low hydrogen pressure
An efficient NixZryO catalyst for hydrogenation of bio-derived methyl levulinate to gamma-valerolactone in water under low hydrogen pressure
复制标题
一种高效 NixZryO 催化剂，用于低氢压力下在水中将生物来源的乙酰丙酸甲酯加氢为 r-戊内酯
DOI：
10.1016/j.apcatb.2018.01.010
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发表时间：
2018
期刊：
影响因子：
--
通讯作者：
Liu XH
中科院分区：
文献类型：
--
作者：
Sun Mengqing;Liu Xiaohui;Xia Qineng;Wang Yanqin;Sun Mengqing;Xia Jie;Wang Haifeng;Liu Xiaohui;Xia Qineng;Wang Yanqin;Liu XH
γ-戊内酯（GVL）已被确定为可持续生产燃料和增值化学品的关键中间体。采用共沉淀法制备了NixZryO催化剂，并将其用于生物衍生的乙酰丙酸甲酯（ML）在水溶液中低压加氢制备GVL。制备了几种不同Ni/Zr摩尔比的催化剂，并通过BET、XRD、H2-TPR、NH3-TPD和XPS等手段对催化剂进行了表征，结果表明它们在ML催化加氢反应中表现出不同的催化活性。Ni 1 Zr 1 O的催化活性最好，在150 °C水溶液中，在0.3MPa的低氢压下，GVL的产率可达96.9%。通过与NiO和Raney Ni催化剂的对比发现，在NiO中引入锆元素后，NixZryO催化剂的催化性能得到了显著的提高。根据XRD、H2-TPR和XPS结果，当引入一定量的锆（例如，Ni/Zr = 1）时，部分Ni与Zr配位或形成NimZrnO准固溶体，不易被H2还原。理论计算表明，形成的Ni − O − Zr物种是上级的纯镍或锆氧化物的吸附ML。活化H2的金属镍和活化ML的Ni-O-Zr物种之间的协同作用被认为加速了γ-戊内酯的产生。此外，Ni 1 Zr 1 O具有良好的催化稳定性，在ML加氢反应的5个循环后仍保持催化性能。
γ-Valerolactone (GVL) has been identified as a key intermediate for the sustainable production of fuels and value-added chemicals. In this work, an efficient NixZryO catalyst was prepared by co-precipitation and used in the low pressure hydrogenation to prepare GVL from bio-derived methyl levulinate (ML) in aqueous solution. Several catalysts that differed in their Ni/Zr molar ratio were prepared and characterized by BET, XRD, H2-TPR, NH3-TPD and XPS, and they exhibited different catalytic activities in the catalytic hydrogenation reaction of ML. The best catalytic activity was realized with Ni1Zr1O, which gave a 96.9% yield of GVL by low hydrogen pressure at 0.3 MPa in the aqueous solution at 150 °C. By comparison with NiO and Raney Ni, it was found that introducing zirconium into nickel oxide remarkably enhanced the performance of the NixZryO catalysts. According to the XRD, H2-TPR and XPS results, when a certain amount of zirconium was introduced (e.g., Ni/Zr = 1), part of the nickel either coordinated with zirconium or formed NimZrnO quasi solid solution and was not readily reduced by H2. Theoretical calculations showed that the formed Ni − O − Zr species was superior to pure nickel or zirconium oxides for the adsorption of ML. The synergy between metallic nickel, which activated H2, and the Ni − O − Zr species, which activated ML, was believed to expedite the production of γ-valerolactone. Moreover, Ni1Zr1O showed good catalytic stability and retained the catalytic performance even after five reaction cycles of the ML hydrogenation.