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Porous Polymer for Heterogeneous Catalysis
Published in Inamuddin, Mohd Imran Ahamed, Rajender Boddula, Porous Polymer Science and Applications, 2022
Vivek Mishra, Simran Aggarwal, Shubham Pandey
In the process of converting glucose to 5-hydroxymethylfurfural (HMF), an important intermediate in synthesizing various chemicals and fuels, a base catalyst is needed in the isomerization of glucose to fructose, and acid catalyst is required in the dehydration of fructose to finally give HMF. But in the acid-catalyzed conversion of fructose to HMF, HMF undergoes hydrolysis to yield levulinic acid (LA) and formic acid (FA) as the by-product, which reduces HMF yield.38 Theoretical simulations have revealed that the superhydrophobic acid catalyst can significantly prevent hydrolysis of HMF, producing HMF as the only product. Acid catalysts based on porous PDVB-SO3H groups gave HMF in high yields.39 For the isomerization of glucose to fructose, a base catalyst having super hydrophilic properties was required which was prepared via copolymerization of 1-vinylimidazole, divinylbenzene, and N,N-methylenebisacrylamide. When super hydrophilic base catalyst (P-VI-0) and superhydrophobic acid catalyst (P-SO3H-154) were used in the conversion of glucose to HMF, HMF was obtained in 95.4% yield (Scheme 6.6). These findings pave the way for the design and development of novel catalysts having high activities and superior selectivities for biomass conversion.
Nanocatalysts from Biomass and for the Transformation of Biomass
Published in Vanesa Calvino-Casilda, Antonio José López-Peinado, Rosa María Martín-Aranda, Elena Pérez-Mayoral, Nanocatalysis, 2019
5-hydroxymethylfurfural (HMF) is produced by acid-catalysed dehydration of fructose and glucose or hydrolysis/dehydration of polysaccharides and can be used as platform molecule for organic synthesis (Rosatella et al. 2011; van Putten et al. 2013). Some products of hydrogenation of HMF that are of high interest because of their applications are 2,5-dihydroxymethyltetrahydrofuran (DHMTHF) and 2,5-dimemylfuran (DMF) (Fig. 4). The first one, used as a solvent and a precursor for polymer synthesis can be obtained in a high yield (around 90%) over Ni-, Pd-and Ru-catalysts, and over a silica-supported Ni-Pd alloy (Ni/Pd = 7) prepared by co-impregnation. DMF was obtained with a 79% yield by vapour-phase hydrogenolysis of HMF with a Cu−Ru/C catalyst (Cu:Ru = 3:2) prepared by incipient wetness impregnation. The catalytic hydrogenation of HMF in supercritical methanol over a Cu-doped porous metal oxide obtained from a hydrotalcite-like material, afforded 48% and 10% yields to DMF and DMTHF, respectively (Hansen et al. 2012).
Microwave Pretreatment of Feedstock for Bioethanol Production
Published in Veera Gnaneswar Gude, Microwave-Mediated Biofuel Production, 2017
5-Hydroxymethylfurfural, HMF is a polyfunctional chemical intermediate and a possible substitute to petroleum based building blocks used in the commercial production of high potential synthetic chemicals. Numerous studies have been reported on the production of HMF from different carbohydrate feedstocks (e.g., cellulose, cellobiose, fructose, glucose, hemicellulose, inulin, sucrose, and xylose) at various efficiencies and reaction conditions. Levulinic acid is another key compound used as raw material for various fuel additive and other platform chemical production. Figure 16 shows the production routes for production of valuable chemicals using HMF and LA as reactants. Table 8 summarizes experimental studies utilizing microwave irradiation to produce HMF and LA (summarized from Mukherjee et al. 2015). These can be produced from starch as well as lignocellulosic feedstock such as fructose, glucose, starch, sucrose and cellulosic waste. Microwave process conditions vary depending on the catalysts and solvents in the reaction.
Honey powder produced by spray drying as an ingredient: A new perspective using a plant-based protein as a carrier
Published in Drying Technology, 2023
Taíse Toniazzo, Alexandre Minami Fioroto, Elias da Silva Araújo, Carmen Cecília Tadini
HMF (5-hydroxymethylfurfural) is a furanic compound produced by sugar degradation by the dehydration of hexoses in an acidic medium. Also, a lesser amount can be produced as an intermediate in the Maillard reaction.[38] The presence of monosaccharides in honey (fructose and glucose), acids and minerals can further enhance the production of this substance.[39] HMF can occur naturally in honey due to the long storage time or during food processing.[40] Therefore, HMF is an important component to control the quality and evaluate the freshness or overheating in honey. Fresh honey showed an HMF value of (37.47 ± 1.04) mg/kg, which is an acceptable value according to Codex Alimentarius.[31] For honey originating in countries where tropical ambient temperature is predominant, the regulation accepts an upper HMF limit of 80 mg/kg of honey; otherwise, this value can be up to 40 mg/kg of honey. The HMF value in this study suggests that there was no inadequate storage or overheating in the honey used in this study.
Glucose conversion to 5-hydroxymethylfurfural with chromium exchanged bentonite and montmorillonite catalysts in different solvents
Published in Chemical Engineering Communications, 2020
Aziz Rahman Aylak, Solmaz Akmaz, Serkan Naci Koc
Energy demand is still increasing rapidly with the advancement of technology and with the rapid growth of the world population. In addition, fossil fuel resources are limited and the problem of the depletion of resources has increased in recent years. However, the interest has been focused on alternative energy resources. The investigation of renewable energy sources and conversion of these resources into products with high economic value has gained importance in recent years. Cellulosic materials are the world's largest renewable resources. 5-Hydroxymethylfurfural (HMF), an important intermediate, leads cellulosic materials to pharmaceutical, plastics and fuel chemicals (Mascal and Nikitin, 2008; Rosatella et al., 2011; Wang et al., 2014). HMF, consisting of alcohol, aldehyde and the furan ring system, is formed by leaving of three water molecules from hexoses in the presence of acid catalyst. The conversion of glucose into HMF takes place more slowly than that of fructose into HMF and selectivity of HMF from glucose is lower. Since glucose is more abundant and also cheaper than fructose, many studies related to dehydration of glucose have been carried out using various catalyst systems (Hu et al., 2009; Yan et al., 2009).
Rapid and efficient conversion of bio-based sugar to 5-hydroxymethylfurfural using amino-acid derived catalysts
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2018
Hongguo Wu, Yancai Liu, Hu Li, Song Yang
In particular, 5-hydroxymethylfurfural (HMF) obtained from biomass-based carbohydrate chemistry is a versatile and key platform chemical, which can be further converted into high-quality fuels and valuable chemicals (Liu and Zhang 2016). Therefore, selective conversion of biomass into HMF via simple and efficient routes has aroused great attention in recent decades (Zhou and Zhang 2016). One of the most important feedstocks from biomass is fructose and increasing interest has been devoted to the selective dehydration of fructose to HMF. For instance, Moreau, Finiels, and Vanoye (2006) used 1-H-3-methyl imidazolium chloride ([HMIM]Cl) as both solvent and catalyst to prepare HMF from fructose, and an HMF yield of 70% was achieved at 80ºC for 45 min. Hu et al. (2013) reported that HMF yields of 95.7% and 88.4% were obtained from fructose and inulin using 1-carboxypropyl-3-methyl imidazolium chloride ([CMIM]Cl) as a catalyst when reactions were carried out at 120ºC after 120 min and 180 min, respectively. When HBr was used as a catalyst in sulfolane, only 60 min was required to obtain a 93.0% yield of HMF from fructose at 100ºC (Caes and Raines 2011). However, these reported catalytic systems with relatively high efficiency often employed nonbiodegradable imidazole-based ionic liquids or strong mineral acids as catalysts, which are harmful to the environment and may corrode the equipment.