Phosphotungstic acid heterogenized by assembly with pyridines for efficient catalytic conversion of fructose to methyl levulinate

Abstract

A high yield of methyl levulinate (82.5%) was achieved from fructose via a one-pot multi-step conversion process using acidic 3-FPYPW as a heterogeneous catalyst.

3-Bromopyridine-Heterogenized Phosphotungstic Acid for Efficient Trimerization of Biomass-Derived 5-Hydroxymethylfurfural with 2-Methylfuran to C21 Fuel Precursor

“…After each cycle of the reaction, the catalyst was removed from the reaction system by centrifugation and then washed with 20 mL ethanol for three times, which was finally dried at 80°C for 24 h. The recovered catalyst was utilized directly for the next run under identical reaction conditions. [50][51][52][53][54][55][56] could also be observed for HPyPW and 3-BrPyPW. This result indicated that even HPW was decorated by different organic species; it could well maintain the original HPW cubic basically.…”

“…This phenomenon can be attributed to the electrostatic interaction between HPW and ligands [48,49]. Moreover, some unknown diffraction peaks could be observed in 3-BrPyPW and HPyPW, and the possible explanation is that two catalysts will absorb some organic moieties, and this phenomenon has been proved by a previous work [51].…”

“…Taking the above problems into consideration, it is highly desirable to heterogenize HPW using a high-efficiency method. For example, Wang et al [50] and Fang et al [51] prepared electric flocculation of HPW and silica-supported HPW heterogeneous catalysts for the con-version of glucose into 5-hydroxymethylfurfural (HMF) with a good yield of 61.7% and 78.3%, respectively. Due to heterogeneous functionalization, these catalysts could be reused at least four or five times without significant loss of catalytic activity.…”

Critical Review on the Synthesis of Levulinate Esters from Biomass-Based Feedstocks and Their Application

“…It can be produced from both C5 carbohydrates and C6 carbohydrates. − The acid-catalyzed system conversion of raw biomass such as oil palm fronds, , wheat straw, , bamboo, , paper pulp, , wood chips, , and switchgrass , to LEs was also developed. LEs can be prepared through effective hydrolysis of lignocellulosic biomass into C5/C6 carbohydrates and then undergo catalytic dehydration into LA with furan-derived compounds (furfuryl alcohol (FFA) and 5-HMF) as intermediates and then LA alcoholysis into LE products over the acid catalyst (Figure ).…”

Metal chloride mediated efficient conversion of hydroxymethylfurfural (HMF) into long-chain levulinate ester

“…For instance, the energy density of ethyl levulinate (EL) is approximately 31.2 MJ L -1 , which is similar to that of gasoline (32.4 MJ L -1 ), and obviously higher than that of ethanol (23.5 MJ L -1 ) (Ghosh et al 2018). Much effort has been currently made to determine the efficient synthesis of short-chain levulinate esters, e.g., methyl levulinate (ML) and EL (Fang et al 2018;Liu et al 2018;Lyu et al 2019;Peixoto et al 2021). However, the oxygen contents of ML and EL are relatively high, which leads to high water miscibilities and low heating values (Jia et al 2020).…”