Widespread production of biomass-derived fuels and chemicals will require cost-effective processes for breaking down cellulose and hemicellulose into their constituent sugars. Here, we report laboratory-scale production of soluble carbohydrates from corn stover, hardwood, and softwood at high yields (70 to 90%) in a solvent mixture of biomass-derived γ-valerolactone (GVL), water, and dilute acid (0.05 weight percent H2SO4). GVL promotes thermocatalytic saccharification through complete solubilization of the biomass, including the lignin fraction. The carbohydrates can be recovered and concentrated (up to 127 grams per liter) by extraction from GVL into an aqueous phase by addition of NaCl or liquid CO2. This strategy is well suited for catalytic upgrading to furans or fermentative upgrading to ethanol at high titers and near theoretical yield. We estimate through preliminary techno-economic modeling that the overall process could be cost-competitive for ethanol production, with biomass pretreatment followed by enzymatic hydrolysis.

The electrocatalytic oxidation technology of biomass-derived oxygenates such as glycerol presents a promising method of coproducing renewable chemicals and hydrogen in an electrochemical reactor system that uses oxidation chemistry and existing proton exchange membrane technology to electrocatalytically convert oxygenates into value-added chemicals and hydrogen. In this paper, we first demonstrate the techno-economic feasibility of the electrocatalytic glycerol oxidation technology with our experimental investigations. Simple and direct conversion of glycerol into glyceraldehyde (GAD), glyceric acid (GLA), and hydroxypyruvic acid (HPA) by anodic oxidation in an electrocatalytic batch reactor over Pt/C catalysts was performed with only water as a stoichiometric chemical oxidant. We also conducted conventional catalytic (non-electrocatalytic) glycerol oxidation using a catalytic batch reactor with pressurized oxygen as the oxidant to compare conventional catalytic performances to that of the electrocatalytic reactor. The electrocatalytic glycerol oxidation process had a yield for GAD, GLA, and HPA production that was ∼1.7 times higher than that of the nonelectrocatalytic process. The turnover frequency of the electrocatalytic process is comparable to and even higher than that of a non-electrocatalytic system. On the basis of the experimental results, we develop process simulation models for both the electrocatalytic and non-electrocatalytic processes and then analyze the energy efficiency and economics of the process models. The minimum selling price (MSP) of GLA for the electrocatalytic process was $2.30/kg of GLA compared to $4.91/kg of GLA for the non-electrocatalytic process.

We develop and evaluate an integrated catalytic conversion strategy, which utilizes both the hemicellulose and cellulose fractions of lignocellulosic biomass to produce liquid hydrocarbon fuels (butene oligomers). In this strategy, the cellulose and hemicellulose fractions are simultaneously converted to levulinic acid (LA), using LA-derived γ-valerolactone (GVL) as a solvent. The LA is then converted to GVL, which is subsequently converted to butene, and then to butene oligomers. To generate the integrated strategy, we develop separation subsystems to achieve experimentally optimized feed concentrations for the catalytic conversion steps. Importantly, to minimize the utility requirements of the overall process, we perform heat integration, which allows us to satisfy all heating requirements from combustion of biomass residues, which are also used to produce steam for electricity generation. In addition, we develop an alternative design in which there is no electricity generation, study alternative feedstocks, and perform sensitivity analyses. Our technoeconomic analysis shows that the integrated strategy using hybrid poplar feedstock leads to a minimum selling price of $4.01 per gallon of gasoline equivalent for butene oligomers if biomass residues are sold as low quality fuel. † Electronic supplementary information (ESI) available. See

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Much of the previous research on carbon capture and storage (CCS) has focused on individual technologies for disposing of CO 2 , such as capture, storage, sequestration, or transport. Moreover, recent research work considers utilization of CO 2 as fuels, chemicals, or nutrients for bioreactors. To efficiently manage CO 2 and the economic benefits achieved by this process, the CO 2 transport and processing infrastructure supporting CCS will have to be constructed at a macro-scale. This paper introduces a scalable and comprehensive infrastructure model for CO 2 utilization and disposal that generates an integrated, profit-maximizing CCS system. The proposed model determines where and how much CO 2 to capture, store, transport, utilize or sequester to maximize total annual profit while meeting the CO 2 mitigation target. The applicability of the proposed model is demonstrated using a case study for treating CO 2 emitted by an industrial complex on the eastern coast of Korea in 2020. The results may be important in systematic planning of a CCS infrastructure and in assisting national and international policy makers to determine investment strategies for developing CCS infrastructures.