Interface synergy between IrOx and H-ZSM-5 in selective C-O hydrogenolysis of glycerol toward 1,3-propanediol
Interface synergy between IrOx and H-ZSM-5 in selective C-O hydrogenolysis of glycerol toward 1,3-propanediol
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IrOx 和 H-ZSM-5 在甘油选择性 C-O 氢解生成 1,3-丙二醇中的界面协同作用
DOI：
10.1016/j.jcat.2019.06.025
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发表时间：
2019
影响因子：
7.3
通讯作者：
Cao Yong
中科院分区：
文献类型：
--
作者：
Wan Xiaoyue;Zhang Qi;Zhu Mingming;Zhao Yi;Liu Yongmei;Zhou Chunmei;Yang Yanhui;Cao Yong
羟基的位点选择性脱氧是获得具有工业潜力的有价值的功能化生物基化合物的重要过程。在这种情况下，一项具有挑战性的任务是在存在大量水的情况下将生物柴油衍生的甘油直接转化为 1,3-丙二醇 (1,3-PDO)，这是新兴聚合物行业的关键组成部分。在此，在不存在 Re 亲氧金属氧化物的情况下，通过研磨辅助浸渍程序制备了负载在 H-ZSM-5 上的单金属铱，并尝试在不存在酸添加剂的情况下作为甘油水相选择性氢解成 1,3-PDO 的有效且可回收的催化剂。结果揭示了控制 Ir 域色散、Ir0/Ir3+ 比率以及总酸/布朗斯台德酸位点数量的必要性。活性与总酸位点和布朗斯台德酸位点的数量呈线性关系，并且在 Ir 诱导的布朗斯台德酸位点（表示为 Ir-O(H)-H-ZSM-5）存在下，1,3-PDO 选择性增加。根据文献报道，我们推测Ir-O(H)-H-ZSM-5是由IrOx和H-ZSM-5之间通过氢溢出和反向氢溢出的界面协同作用生成的。基于广泛的表征和催化反应结果，还推测了阐明 Ir-O(H)-H-ZSM-5 位点在甘油氢解中作用的反应机制。
Site-selective deoxygenation of hydroxyl groups represents essential processes to access valuable functionalized bio-based compounds with industrial potential. One of the challenging tasks in this context is to convert biodiesel-derived glycerol in the presence of abundant water directly to 1,3-propanediol (1,3-PDO), a key component of the emerging polymer industry. Herein, a monometallic iridium supported on H-ZSM-5 in the absence of Re oxophilic metal oxides was prepared via grinding-assisted impregnation procedures and attempted as an effective and recyclable catalyst for the aqueous-phase selective hydrogenolysis of glycerol toward 1,3-PDO in the absence of acid additives. The results revealed the necessity to control the Ir domain dispersions, Ir0/Ir3+ratio and the amounts of overall acid/Brönsted acid sites. Activity depended linearly on the amount of overall and Brönsted acid sites, and 1,3-PDO selectivity increased in the presence of Ir-induced Brönsted acid sites, denoted as Ir-O(H)-H-ZSM-5. We speculate that Ir-O(H)-H-ZSM-5 are generated by the interfacial synergistic interaction between IrOxand H-ZSM-5 through hydrogen spillover and reverse hydrogen spillover according to the reported literatures. The reaction mechanism to elucidate the role of Ir-O(H)-H-ZSM-5 sites in glycerol hydrogenolysis was also postulated based on extensive characterization and catalytic reaction results.