Platform chemical from lignocellulosic biomass

The production of 5-HMF and furfural from lignocellulosic biomass (com stalk, rice straw and pine wood) in ILs, catalyzed by CrCls imder microwave irradiation, was reported with yields 45-52% and 23-31% respectively, from corn stalk, rice straw and pine wood in less than 3 min (Table 2) [3]. This method paved the way for energy-efficient and cost-effective conversion of biomass into biofuels and platform chemicals [3]. 

Abstract The synthesis and chemistry of 5-(hydroxymethyl)furfural (HMF), 5-(chloromethyl)furfural (CMF), and levulinic acid (LA), three carbohydrate-derived platform molecules produced by the chemical-catalytic processing of lignocellulosic biomass, is reviewed. Starting from the historical derivation of these molecules and progressing through modem approaches to their production from biomass feedstocks, this review will then survey their principal derivative chemistries, with particular attention to aspects of commercial relevance, and discuss the relative merits of each molecule in the future of biorefining. 

As discussed in detail in Chapter 1 [1], the chemical-catalytic approach to biomass valorization is poised to come to the fore of biorefinery operations due to its advantages over microbial and thermochemical processing of lignocellulosic feedstocks. Below, we consider three mainstream platform chemicals, collectively referred to as furanics, that are derived from the acid-catalyzed dehydration of carbohydrates. The first, 5-(hydroxymethyl)furfural, or HMF 1, is an icon of the biorefinery movement. With derivatives that branch out over multiple product manifolds, HMF is a recognized commercial opportunity for whoever can manage to produce it economically, and approaches towards the realization of this aim will be discussed. 

This chapter surveys different process options to convert terpenes, plant oils, carbohydrates and lignocellulosic materials into valuable chemicals and polymers. Three different strategies of conversion processes integrated in a biorefinery scheme are proposed from biomass to bioproducts via degraded molecules , from platform molecules to bioproducts , and from biomass to bioproducts via new synthesis routes . Selected examples representative of the three options are given. Attention is focused on conversions based on one-pot reactions involving one or several catalytic steps that could be used to replace conventional synthetic routes developed for hydrocarbons. 

These processes involve a multistep transformation from the carbohydrate fraction to the value-added products which makes most of them far from commercialization. Hence, intensive efforts are stiU required to enable scale up of synthetic protocols developed on a lab-scale into industrial processes. Some of the current drawbacks might be overcome by the one-pot transformation of lignocellulose carbohydrates in value-added chemicals without isolation of the intermediate platform molecules (Delidovich et al., 2014). Moreover, nanoporous materials, such as acidic, basic or metallic catalysts (zeolites, mesoporous silicas, microporous/mesoporous carbons, resins, metal oxides, etc.), wUl play a crucial role in this biomass transformation (Wang and Xiao, 2015). 

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