Engineering zirconium-based UiO-66 for effective chemical conversion of <scp>d</scp>-xylose to lactic acid in aqueous condition
Panyapat Ponchai, Kanyaporn Adpakpang, Sutarat Thongratkaew, Kawisa Chaipojjana, Suttipong Wannapaiboon, Siwarut Siwaipram, Kajornsak Faungnawakij, Sareeya Bureekaew
Abstract
) located at the defect sites. The catalytic performances of UiO-66 catalysts synthesized through a modulator-free approach (UiO-66) and an acetic acid modulator-assisted approach (UiO-66(AA)) are distinct due to the different concentrations of local defects. The UiO-66 catalyst possessing a higher defect concentration exhibits a superior LA yield of 1.17 mol from 1 mol of xylose. However, the UiO-66(AA) catalyst with higher crystallinity shows better selectivity for LA over furfural, a side product from the competitive pathway. The enhanced LA yield and excellent selectivity can be achieved by the removal of AA from UiO-66(AA) resulting in a novel MOF catalyst (UiO-66(AA)*) which provides more accessible catalytic sites with retained crystallinity. This work highlights that the structural engineering of MOF catalysts is crucial for the fine-tuning of their catalytic properties.