Incorporation of Al³⁺ Sites on Brønsted Acid Metal–Organic Frameworks for Glucose‐to‐Hydroxylmethylfurfural Transformation

Abstract

Abstract5‐hydroxylmethylfurfural (HMF) is a bio‐based chemical that can be prepared from natural abundant glucose by using combined Brønsted–Lewis acid catalysts. In this work, Al3+ catalytic site has been grafted on Brønsted metal–organic frameworks (MOFs) to enhance Brønsted–Lewis acidity of MOF catalysts for a one‐pot glucose‐to‐HMF transformation. The uniform porous structure of zirconium‐based MOFs allows the optimization of both acid strength and density of acid sites in MOF‐based catalysts by incorporating the desired amount of Al3+ catalytic sites at the organic linker. Al3+ sites generated via a post‐synthetic modification act as Lewis acid sites located adjacent to the Brønsted sulfonated sites of MOF structure. The local structure of the Al3+ sites incorporated in MOFs has been elucidated by X‐ray absorption near‐edge structure (XANES) combined with density functional theory (DFT) calculations. The cooperative effect from Brønsted and Lewis acids located in close proximity and the high acid density is demonstrated as an important factor to achieve high yield of HMF.

Progress in Selective Conversion of 5‐Hydroxymethylfurfural to DHMF and DMF

“…[12][13] In order to make full use of biomass resource, fine chemicals, and biological liquid fuel oil can be prepared by hydrogenation, oxidation, hydrolysis, esterification, reductive depolymerisationenzymatic hydrolysis, and catalytic pyrolysis. [14][15][16][17][18][19][20][21][22][23][24][25][26] 5-hydroxymethylfurfural (HMF) is a very momentous platform compound, [27][28][29][30] HMF was obtained though the dehydration of biomass-derived carbohydrates, such as glucose, [31][32][33][34][35] fructose, [36][37][38][39][40] sucrose, [41][42][43][44][45] inulin, [46][47][48][49][50] cellobiose [51][52][53][54][55] and cellulose. [29,[56][57][58]…”

“…In order to make full use of biomass resource, fine chemicals, and biological liquid fuel oil can be prepared by hydrogenation, oxidation, hydrolysis, esterification, reductive depolymerisationenzymatic hydrolysis, and catalytic pyrolysis [14–26] . 5‐hydroxymethylfurfural (HMF) is a very momentous platform compound, [27–30] HMF was obtained though the dehydration of biomass‐derived carbohydrates, such as glucose, [31–35] fructose, [36–40] sucrose, [41–45] inulin, [46–50] cellobiose [51–55] and cellulose [29,56–60] . Microwave technology is a simple and efficient conversion technology that can convert biomass to HMF.…”

Zn(II)/Cd(II)-Based Metal–Organic Frameworks as Bifunctional Materials for Dye Scavenging and Catalysis of Fructose/Glucose to 5-Hydroxymethylfurfural

“…Probably, ADES- 4 with functionally decorated hydroxyl and acylamide groups may synergistically be involved in the two-step process involving glucose to fructose conversion followed by dehydration favoring efficient product yield of HMF. It is well documented in the literature that the mechanism involving glucose to HMF conversion proceeds via isomerization followed by dehydration. ,− In the first catalytic cycle, fructofuranose was generated via a 1,2-hydride transfer, followed by cyclization from α-glucopyranose. The probable mechanism in the present investigation also follows the same pathway in which synergistic effect engendered through the surface, the layered channels, and the availability of Brønsted acid sites on functionalized linkers in both MOFs plays an important role in the conversion of glucose/fructose to HMF.…”

A survey of recent progress on novel catalytic materials with precise crystalline structures for oxidation/hydrogenation of key biomass platform chemicals

“…Recently, Oozeerally and Kongpatpanich have investigated the catalytic performance of UiO-66-based materials with different modifications for one pot reaction of GLU to HMF in water independently. 108,109 It was found that the catalytic performance of these MOFs could be modulated via introducing structural defects, modulating the particle size, and introducing functional groups.…”