Y₂O₃系触媒を用いた均一系塩基フリー条件下でのグルコースからの乳酸合成

Abstract

Methods to catalytic conversion of glucose into lactic acid (LA), which is a versatile platform chemical, have been widely investigated. Herein, various kinds of metal oxide catalysts were used for lactic acid (LA) production from glucose under strong homogeneous base-free conditions. Among the metal oxides tested, Y2O3 afforded LA in moderate yield (33 %) together with trioses (dihydroxyacetone and glyceraldehyde) and fructose. It was found that the Y2O3/SiO2 catalyst can effectively catalyze the transformation of glucose into LA. Compared to Y2O3, the LA yield was remarkably improved (45 %). The characterization results showed that Y(OH)3 was highly dispersed on the Y2O3/SiO2 catalyst, acting as a Brønsted base and promoting LA formation from pyruvaldehyde (PA). Brønsted acid sites (hydroxyl groups) located at the interface between Y(OH)3 and SiO2 promoted the dehydration of trioses to form PA. The acid and base sites on the Y2O3/SiO2 catalyst functioned in concert to ensure that the overall reaction proceeded efficiently.

Homogeneous and Heterogeneous Catalysis of Glucose to Lactic Acid and Lactates: A Review

“…Similarly, by grafting Cr(III) on Al 2 O 3 by incipient wetness impregnation,Kosri et al (2021) achieved 74% LA from glucose, confirming the promoting effect of well-tuned bimetallic Lewis acidic metal systems on glucose reactions 77. Hata et al (2021) tested glucose conversion to LA using TiO 2 , Al 2 O 3 , Nb 2 O 5 , MgO, ZnO, and Y 2 O 3 , confirming that both intrinsic Lewis acidity and Brønsted basicity have a considerable effect on the product distribution 80. XRD detected Y(OH) 3 groups at the surface of Y 2 O 3 and 0.30 g g −1 Y 2 O 3 /SiO 2 frameworks, which are Brønsted bases andFigure 7.…”

“…Hata et al (2021) tested glucose conversion to LA using TiO 2 , Al 2 O 3 , Nb 2 O 5 , MgO, ZnO, and Y 2 O 3 , confirming that both intrinsic Lewis acidity and Brønsted basicity have a considerable effect on the product distribution. 80 XRD detected Y(OH) 3 groups at the surface of Y 2 O 3 and 0.30 g g –1 Y 2 O 3 /SiO 2 frameworks, which are Brønsted bases and assist the retro-aldol reaction and dehydration of DHA to PA. Y 3+ arising from the oxide dissociation promotes glucose isomerization to fructose as a Lewis acid in a bidentate coordination mode. 80 A catalytic activity enhancement has been noted by Li et al (2016) when grafting Y 2 O 3 on SiO 2 .…”

“… 80 XRD detected Y(OH) 3 groups at the surface of Y 2 O 3 and 0.30 g g –1 Y 2 O 3 /SiO 2 frameworks, which are Brønsted bases and assist the retro-aldol reaction and dehydration of DHA to PA. Y 3+ arising from the oxide dissociation promotes glucose isomerization to fructose as a Lewis acid in a bidentate coordination mode. 80 A catalytic activity enhancement has been noted by Li et al (2016) when grafting Y 2 O 3 on SiO 2 . When grafted, Y 2 O 3 is more subject to dissociation, forming the highly Lewis acidic surface Y 3+ , increasing the cellulose-to-LA yield from 33 to 45%.…”

“…assist the retro-aldol reaction and dehydration of DHA to PA. Y 3+ arising from the oxide dissociation promotes glucose isomerization to fructose as a Lewis acid in a bidentate coordination mode 80. A catalytic activity enhancement has been noted byLi et al (2016) when grafting Y 2 O 3 on SiO 2 .…”