Rakngam Issaraporn, Khemthong Pongtanawat, Osakoo Nattawut, Rungnim Chompoonut, Youngjan Saran, Thongratkaew Sutarat, Pengsawang Aniwat, Rungtaweevoranit Bunyarat, Faungnawakij Kajornsak, Kidkhunthod Pinit, Chanlek Narong, Khunphonoi Rattabal, Loiha Sirinuch, Prasitnok Khongvit, Wittayakun Jatuporn
School of Chemistry, Institute of Science, Suranaree University of Technology (SUT), Nakhon Ratchasima, 30000, Thailand.
National Nanotechnology Center (NANOTEC), National Science and Technology Development Agency (NSTDA), Pathumthani, 12120, Thailand.
Chempluschem. 2023 Nov;88(11):e202300326. doi: 10.1002/cplu.202300326. Epub 2023 Oct 18.
5-Hydroxymethylfurfural (5-HMF) synthesized through glucose conversion requires Lewis acid (L) site for isomerization and Brønsted acid (B) site for dehydration. The objective of this work is to investigate the influence of the metal type of Al-SBA-15-supported phosphates of Cr, Zr, Nb, Sr, and Sn on glucose conversion to 5-HMF in a NaCl-H O/n-butanol biphasic solvent system. The structural and acid property of all supported metal phosphate samples were fully verified by several spectroscopic methods. Among those catalysts, CrPO/Al-SBA-15 provided the best performance with the highest glucose conversion and 5-HMF yield, corresponding to the highest total acidity of 0.65 mmol/g and optimal L/B ratio of 1.88. For CrPO/Al-SBA-15, another critical parameter is the phosphate-to-chromium ratio. Moreover, DFT simulation of glucose conversion to 5-HMF on the surface of the optimized chromium phosphate structure reveals three steps of fructose dehydration on the Brønsted acid site. Finally, the optimum reaction condition, reusability, and leaching test of the best catalyst were determined. CrPO/Al-SBA-15 is a promising catalyst for glucose conversion to high-value-added chemicals in future biorefinery production.
通过葡萄糖转化合成的5-羟甲基糠醛（5-HMF）的异构化需要路易斯酸（L）位点，脱水需要布朗斯特酸（B）位点。本工作的目的是研究Cr、Zr、Nb、Sr和Sn的Al-SBA-15负载磷酸盐的金属类型对在NaCl-H₂O/正丁醇双相溶剂体系中葡萄糖转化为5-HMF的影响。所有负载型金属磷酸盐样品的结构和酸性通过几种光谱方法进行了充分验证。在这些催化剂中，CrPO₄/Al-SBA-15表现最佳，葡萄糖转化率和5-HMF产率最高，总酸度为0.65 mmol/g，L/B比为1.88。对于CrPO₄/Al-SBA-15，另一个关键参数是磷酸盐与铬的比例。此外，在优化的磷酸铬结构表面上葡萄糖转化为5-HMF的密度泛函理论（DFT）模拟揭示了在布朗斯特酸位点上果糖脱水的三个步骤。最后，确定了最佳催化剂的最佳反应条件、可重复使用性和浸出试验。CrPO₄/Al-SBA-15是未来生物炼制生产中葡萄糖转化为高附加值化学品的一种有前景的催化剂。
