Efficient catalytic conversion of corn stalk and xylose into furfural over sulfonated graphene in γ-valerolactone

Abstract

Sulfonated graphene (SG) was prepared and employed to convert corn stalk and xylose into furfural.Transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FT-IR) were used to characterize SG. The effects of reaction time, temperature, substrate loading, catalyst dosage and solvents on the reaction were researched and optimized. SG exhibited high catalytic activity in the conversion of xylose and corn stalk to furfural. A fairly high furfural yield of 96% was achieved at 150 C from xylose and a 71.9% furfural yield was obtained when using a 10.7 ratio (mass ratio: xylose to SG) at 140 C. While a 48% furfural yield was obtained from corn stalk (based on the starting combined moles of xylan and glucan in corn stalk; yield was >100%, if based on only xylan) using a substrate loading (corn stalk to catalyst mass ratio) of 2.14 and a 19% 5-hydroxymethylfurfural (5-HMF) yield was obtained. What's more, a 43.9% yield of furfural was obtained in only 20 min. In addition, the reusability of SG was also investigated and shown to have good stability for xylose dehydration.

Mechanochemical Synthesis of Sulfonated Palygorskite Solid Acid Catalysts for Selective Catalytic Conversion of Xylose to Furfural

“…When the xylose initial concentration was increased to 40, 80, and 120 g/L, although more than 93% of xylose was converted in all of the cases, the furfural yield gradually decreased to 83, 75, and 70%, respectively. The decreases in the furfural yield with increasing initial xylose concentration should be resulting from the occurrence of the side-reactions such as fragmentation, condensation, and resinification, as the higher xylose initial loading concentration increases the collision probability among the xylose, furfural, and the other intermediate molecules. , However, a high furfural yield of 70% could be achieved at a high xylose initial concentration of 120 g/L in the catalytic process, which is of importance for the practical application of the furfural production from xylose.…”

Solid Acid Catalyst Derived from Cotton for Conversion of Xylose and Corn Cob to Furfural

“…[15] Sulfonic group can be grafted on the carbon by sulfonation of carbon with concentrated sulfuric acid, or by pyrolysis of organic matter to form polycyclic aromatic hydrocarbon carbon and then sulfonation. [10] Pang et al [16] employed activated carbon as raw material for sulfonation at 250 °C for 24 h to prepare sulfonated carbon-based solid acid, which can achieve 94.4 % conversion for cellulose and 74.5 % yield for glucose. Qi et al [17] obtained carbon-based solid acid from cellulose and sulfuric acid, which can catalytic conversion of corn cob to 78.1 % xylose.…”

“…Among the reported heterogeneous catalysts, carbon‐based solid acid with sulfonic group has attracted extensive attention for their high chemical activity, thermal stability, specific surface area, and low production cost [15] . Sulfonic group can be grafted on the carbon by sulfonation of carbon with concentrated sulfuric acid, or by pyrolysis of organic matter to form polycyclic aromatic hydrocarbon carbon and then sulfonation [10] . Pang et al [16] employed activated carbon as raw material for sulfonation at 250 °C for 24 h to prepare sulfonated carbon‐based solid acid, which can achieve 94.4 % conversion for cellulose and 74.5 % yield for glucose.…”

“…Homogeneous acid catalysts suffer the problems of equipment corrosion, environmental pollution, and no recyclability of acidic waste. [10] Heterogeneous catalysts have the advantages of high catalytic activity, recycling and environmental protection. Therefore, heterogeneous acid catalysts attract the researchers' attention for conversion of xylose and biomass into furfural, mainly including metal oxides, [11] molecular sieves, [12] and ion exchange resins catalysts.…”

“…Industrially, furfural is prepared from biomass by using homogeneous mineral acid catalyst of H 2 SO 4 or HCl as for one‐step conversion production. Homogeneous acid catalysts suffer the problems of equipment corrosion, environmental pollution, and no recyclability of acidic waste [10] . Heterogeneous catalysts have the advantages of high catalytic activity, recycling and environmental protection.…”