Songtawee Siripit, Rungtaweevoranit Bunyarat, Klaysom Chalida, Faungnawakij Kajornsak
NanoCatalysis and Molecular Simulation Research Group, National Nanotechnology Center (NANOTEC), National Science and Technology Development Agency (NSTDA) Pathumthani 12120 Thailand
Center of Excellence in Particle and Material Processing Technology, Department of Chemical Engineering, Faculty of Engineering, Chulalongkorn University Bangkok Thailand.
RSC Adv. 2021 Sep 1;11(47):29196-29206. doi: 10.1039/d1ra06002c.
5-Hydroxymethylfurfural (HMF) derived from cellulosic sugars has become increasingly important as a platform chemical for the biorefinery industry because of its versatility in the conversion to other chemicals. Although HMF can be produced in high yield from fructose dehydration, fructose is rather expensive because it requires multiple processing steps. On the other hand, HMF can be produced directly from highly abundant glucose, which could reduce time and cost. However, an effective and multifunctional catalyst is needed to selectively promote the glucose-to-HMF reaction. In this work, we report a bifunctional phosphated titanium dioxide as an efficient catalyst for such a reaction. The best catalyst exhibits excellent catalytic performance for the glucose conversion to HMF with 72% yield and 83% selectivity in the biphasic system. We achieve this by tuning the solvent system, controlling the amount of Brønsted and Lewis acid sites on the catalyst, and modification of the reaction setup. From the analysis of acid sites, we found that the addition of phosphate group (Brønsted acid site) onto the surface of TiO (Lewis acid site) significantly enhanced the HMF yield and selectivity when the optimum ratio of Brønsted and Lewis acid sites is reached. The high catalytic activity, good reusability, and simple preparation method of the catalyst show a promise for the potential use of this catalytic system on an industrial scale.
源自纤维素糖的5-羟甲基糠醛（HMF）作为生物炼制行业的一种平台化学品变得越来越重要，因为它在转化为其他化学品方面具有多功能性。尽管HMF可通过果糖脱水高产率生产，但果糖相当昂贵，因为它需要多个加工步骤。另一方面，HMF可直接由含量丰富的葡萄糖生产，这可以减少时间和成本。然而，需要一种有效且多功能的催化剂来选择性地促进葡萄糖到HMF的反应。在这项工作中，我们报道了一种双功能磷酸化二氧化钛作为该反应的高效催化剂。最佳催化剂在双相体系中对葡萄糖转化为HMF表现出优异的催化性能，产率为72%，选择性为83%。我们通过调整溶剂体系、控制催化剂上布朗斯特和路易斯酸位点的数量以及改进反应装置来实现这一点。通过对酸位点的分析，我们发现当达到布朗斯特和路易斯酸位点的最佳比例时，在TiO（路易斯酸位点）表面添加磷酸基团（布朗斯特酸位点）可显著提高HMF的产率和选择性。该催化剂的高催化活性、良好的可重复使用性和简单的制备方法表明该催化体系在工业规模上具有潜在应用前景。
