Replacing petroleum by biomass can be economically feasible by generating revenue from the three primary biomass constituents.

Plants have convergently evolved to use monolignol ferulate conjugates to produce lignins containing chemically labile backbone esters.

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Fructose is not only an important food and beverage ingredients, but also a renewable resource for production of 5-hydroxymethylfurfural. This study investigated nontoxic basic amino acids (arginine, lysine, and histidine) as isomerization catalysts to isomerize glucose to fructose in water. The results showed that arginine was the most effective isomerization catalyst with a 31% maximum fructose yield with 76% selectivity achieved under the investigated reaction conditions. A mechanistic study verified that the isomerization reaction catalyzed by arginine proceeded through an enediol intermediate, which formed after the deprotonation at C-2 position of acyclic glucose.

The hydroxycinnamic acids p‐coumaric acid (pCA) and ferulic acid (FA) add diversity to the portfolio of products produced by using grass‐fed lignocellulosic biorefineries. The level of lignin‐bound pCA in Zea mays was modified by the alteration of p‐coumaroyl‐CoA monolignol transferase expression. The biomass was processed in a lab‐scale alkaline‐pretreatment biorefinery process and the data were used for a baseline technoeconomic analysis to determine where to direct future research efforts to couple plant design to biomass utilization processes. It is concluded that future plant engineering efforts should focus on strategies that ramp up accumulation of one type of hydroxycinnamate (pCA or FA) predominantly and suppress that of the other. Technoeconomic analysis indicates that target extraction titers of one hydroxycinnamic acid need to be >50 g kg−1 biomass, at least five times higher than observed titers for the impure pCA/FA product mixture from wild‐type maize. The technical challenge for process engineers is to develop a viable process that requires more than 80 % reduction of the isolation costs.

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Dilute aqueous solutions of furfural were produced in high yield from biomass hydrolysates using an acid-catalyzed batch reactive distillation process that separated the vapor phase from the aqueous reactant medium. Hot water hydrolysates from hybrid poplar, miscanthus, switchgrass and corn stover were dehydrated using sulfuric acid. The vapor fraction from the reactor was condensed to produce furfural in excess of 85% of the theoretical yield based on total pentose. Using xylose as the model compound, and temperature and acid concentration as the variables, the process conditions were optimized by the construction of a three-level statistical model. Hot water hydrolysis of biomass provided with a celluloserich solid fraction which has potential for conversion into pulp or cellulosic ethanol, while the liquid fraction, rich in hemicellulose sugars, was converted into furfural. Fractionating the biomass allows for exploration of the concept of the integrated biorefinery where the hemicellulose sugars are not underutilized or encountered as potential inhibitors during microbial conversions of the solid stream, but are converted into furfural, a valuable chemical precursor. The availability of the cellulose fraction for further conversion into pulp or ethanol gives the current process a major advantage over the conventional batch process used in industry, where theoretical yields do not exceed 45-50% with the conspicuous absence of a usable cellulose stream.

This study investigated polyethylenimines (PEIs) with varied architectures as low toxicity and efficient catalysts for aqueous isomerization of glucose to fructose. Under the investigated reaction conditions, the studied PEIs achieved 33–36% maximum fructose yields with 66–77% selectivity at 110–120 °C, with the branched PEI generally outperforming the linear and comb PEIs. Moreover, with 1 wt % sodium chloride, the PEIs achieved 35–38% maximum fructose yields with 61–72% selectivity at 110 °C. After modification through room temperature cross-linking, the branched PEI was transformed into a recyclable heterogeneous catalyst with similar isomerization performance (30% fructose yield and 78% fructose selectivity at 120 °C) to the homogeneous PEIs. Remarkably, in the presence of neutral salts, the heterogeneous PEI achieved an approximately 41% fructose yield with 72–78% selectivity at 110 °C and showed an excellent reusability.