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Utilization of renewable carbon source, especially non-food biomass is critical to address the climate change and future energy challenge. Current chemical and enzymatic processes for producing cellulosic sugars are multistep, and energy- and water-intensive. Techno-economic analysis (TEA) suggests that upstream lignocellulose processing is a major hurdle to the economic viability of the cellulosic biorefineries. Process intensification, which integrates processes and uses less water and energy, has the potential to overcome the aforementioned challenges. Here, we demonstrate a one-pot depolymerization and saccharification process of woody biomass, energy crops, and agricultural residues to produce soluble sugars with high yields. Lignin is separated as a solid for selective upgrading. Further integration of our upstream process with a reactive extraction step makes energy-efficient separation of sugars in the form of furans. TEA reveals that the process efficiency and integration enable, for the first time, economic production of feed streams that could profoundly improve process economics for downstream cellulosic bioproducts. [ABSTRACT FROM AUTHOR]

We have previously shown that 2,5-dimethylfuran (DMF) can be produced selectively from 5-hydroxymethylfurfural in up to 80 % yield via catalytic transfer hydrogenation with 2-propanol as a hydrogen donor and Ru/C as a catalyst. Herein, we investigate the active phase of the Ru/C catalyst by using extended X-ray absorption fine structure, X-ray photoelectron spectroscopy, and high-resolution TEM analyses. The results reveal that RuO2 is the dominant phase in the fresh (active) catalyst and is reduced to metallic Ru during the reaction with the hydrogen produced in situ from 2-propanol. The deactivation of the catalyst is correlated with the reduction of the surface of RuO2. Reactivity studies of individual phases (bulk RuO2 and reduced Ru/C catalysts) indicate that RuO2 mainly catalyzes the Meerwein-Ponndorf-Verley reaction of 5-hydroxymethylfurfural that produces 2,5-bis(hydroxymethyl)furan and the etherification of 2,5-bis(hydroxymethyl)furan or other intermediates with 2-propanol and that the reduced Ru/C catalyst has moderate hydrogenolysis activity for the production of DMF (30 % selectivity) and other intermediates (20 %). In contrast, a physical mixture of the two phases increases the DMF selectivity up to 70 %, which suggests that both metallic Ru and RuO2 are active phases for the selective production of DMF. The oxidation of the reduced Ru/C catalyst at different temperatures and the in situ hydrogen titration of the oxidized Ru/C catalysts were performed to quantify the bifunctional role of Ru and RuO2 phases. The mild oxidation treatment of the Ru/C catalyst at 403 K could activate the catalyst for the selective production of DMF in up to 72 % yield by generating a partially oxidized Ru catalyst. [ABSTRACT FROM AUTHOR]

RuC ees′ transfer: Transfer hydrogenation using alcohols as hydrogen donors and supported ruthenium catalysts results in the selective conversion of hydroxymethylfurfural to dimethylfuran (>80 % yield). During transfer hydrogenation, the hydrogen produced from alcohols is utilized in the hydrogenation of hydroxymethylfurfural. [ABSTRACT FROM AUTHOR]

The Inside Cover picture shows multipurpose use of sugars produced from varieties of advantageous sourced lignocellulosic biomass by an integrated one‐step process. This new energy‐ and water‐efficient process yields up to 95 % theoretical amount of sugars in an inorganic salt solution. The high efficiency and easiness of separation of the products create favorable economics that can enable bio‐based products that are cost‐competitive and sustainable. More details can be found in the Communication by Sadula et al. on page 2566 in Issue 12, 2017 (DOI: 10.1002/cssc.201700183). [ABSTRACT FROM AUTHOR]

Selective hydrodeoxygenation (HDO) of 5-hydroxymethylfurfural to 2,5-dimethylfuran is of great importance. We reveal a simple pathway for green and efficient HDO using readily available copper with in-situ hydrogen generation. A highly dispersed Cu/PBSAC catalyst consisting of small metallic Cu0 nanoparticles carries out isopropyl alcohol (IPA) dehydrogenation and subsequent HDO of HMF. Density functional theory calculations reveal that the dehydrogenation of IPA is more favorable on Cu(211) with a lower energy barrier of ~0.6 eV. This facet exists in a higher ratio on nanosized catalysts. Batch reactions using Cu/PBSAC at 190 °C exhibited 91.9% HMF conversion and 71.7% DMF selectivity in 6 hr, and > 96% DMF yield in 10 hr. The mechanical strength of the carbon support is ideal for continuous processing for increased productivity; we demonstrate a > 90% DMF yield at 1/WHSV of 2.4 hr. The process demonstrated here can be integrated with upstream HMF separation utilizing carbon adsorbents. [Display omitted] • Nanosized copper is an excellent catalyst for HMF HDO and IPA dehydrogenation. • Earth abundant metal and in situ hydrogen generation are ideal for the industry. • Metal size effect on reactivity improvement is explained by simulations. • Cu(211) is crucial active site; more exists on small particles. • The catalyst is suitable for continuous processing, showcasing high 92% DMF yield. [ABSTRACT FROM AUTHOR]