Production of levulinic acid from glucose by dual solid‐acid catalysts

Abstract

Levulinic acid (LA) is a versatile specialty chemical usable as a building-block for synthesis of various chemicals. In this study, a series of solid Lewis acid catalysts were prepared and tested for glucose to fructose isomerization. We also tested Amberlyst-15, primarily a Bronsted solid acid with limited -sites of Lewis acid, to investigate conversion of fructose to LA. Among the Lewis solid acid catalysts tested, tin imbedded on large-pore zeolite (SnBeta) has shown the highest specific activity in isomerization of glucose to fructose in aqueous media. The concurrent use of the dual-catalysts of Sn-beta and Amberlyst-15 was further investigated. The dual-acid catalyst has improved the yield of LA over that of Amberlyst-15 alone, from 37 to 45% of the theoretical maximum. The improvement was due to enhanced isomerization of glucose to fructose by Sn-Beta. Stability tests have shown that the Sn-beta zeolite catalyst loses 20% of its activity after five consecutive batch-cycles. The activity of this catalyst, however, was fully regenerated by calcination. Ambelyst-15 also suffers from deactivation, which is lower than that of Sn-Beta. The deactivation is primarily due to humin deposit on the surface of the catalyst.

Valorization of Chitosan as Food Waste of Aquatic Organisms into 5‐Hydroxymethylfurfural by Sulfamic Acid‐Catalyzed Conversion Process

“…Unfortunately, the attempts to detect the proof of deamination in the aqueous product solution have been unsuccessful by this work and other reports ,,. Recently, some reports indicated the positive synergistic and pivotal effects on 5‐HMF and LA production from glucose using combined Brønsted and Lewis acids . They reported the combination of Brønsted and Lewis acids such as Sn‐β zeolite and PTSA‐POM, AlCl 3 ‐HCl, CrCl 3 ‐H 3 PO 4 , AlCl 3 ‐maleic acid, Sn‐beta and Amberlyst 15 as catalysts for glucose conversion to 5‐HMF and LA.…”

“…Recently, some reports indicated the positive synergistic and pivotal effects on 5‐HMF and LA production from glucose using combined Brønsted and Lewis acids . They reported the combination of Brønsted and Lewis acids such as Sn‐β zeolite and PTSA‐POM, AlCl 3 ‐HCl, CrCl 3 ‐H 3 PO 4 , AlCl 3 ‐maleic acid, Sn‐beta and Amberlyst 15 as catalysts for glucose conversion to 5‐HMF and LA. Especially, some works proposed the conversion mechanism of glucose using the combination of Brønsted and Lewis acids ,,.…”

“…They reported the combination of Brønsted and Lewis acids such as Sn‐β zeolite and PTSA‐POM, AlCl 3 ‐HCl, CrCl 3 ‐H 3 PO 4 , AlCl 3 ‐maleic acid, Sn‐beta and Amberlyst 15 as catalysts for glucose conversion to 5‐HMF and LA. Especially, some works proposed the conversion mechanism of glucose using the combination of Brønsted and Lewis acids ,,. They suggested that firstly glucose is mostly isomerized to fructose by Lewis acid, however, the formation of 5‐HMF by fructose dehydration was promoted by both Brønsted and Lewis acids.…”

“…They suggested that firstly glucose is mostly isomerized to fructose by Lewis acid, however, the formation of 5‐HMF by fructose dehydration was promoted by both Brønsted and Lewis acids. In addition, the degradation (rehydration) of 5‐HMF to LA accelerated by Brønsted acid ,,. Additionally, some researchers reported that sulfamic acid has dual‐catalyst sites with both Brønsted acid and Lewis acid sites owing to its tautomer structure ,,.…”

Isomerization Kinetics of Glucose to Fructose in Aqueous Solution with Magnesium‐Aluminum Hydrotalcites

“…Glucose is an abundant renewable bio‐based platform compound as it can be readily derived from hydrolysis of cellulose, starch and hemicellulose, and it can also be used for a variety of value‐added chemicals, including levulinic acid (LA), 5‐hydroxymethylfurfural (HMF) and 2,5‐furandicarboxylic acid (FDCA) . During conversion process of glucose to these chemicals, isomerization of glucose to fructose is usually an indispensable step, having significant effect on the conversion efficiency to desired products.…”