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The orbital modulation and surface lattice reconstruction represent an effective strategy to regulate the interaction between catalyst interface sites and intermediates, thereby enhancing catalytic activity and selectivity. In this study, the crystal surface of Au-K/CeO 2 catalyst can undergo reversible transformation by tuning the coordination environment of Ce, which enables the activation of the C β -H bond and the oxidative cleavage of the C β-O and C α -C β bonds, leading to the cleavage of 2-phenoxy-1-phenylethanol. The t 2g orbitals of Au 5d hybridize with the 2p orbitals of lattice oxygen in CeO 2 via π-coordination, modulating the coordination environment of Ce 4 f and reconstructing the lattice oxygen in the CeO 2 framework, as well as increasing the oxygen vacancies. The interface sites formed by the synergy between Au clusters in the reconstructed Ce-O L1 -Au structure and doped K play dual roles. On the one hand, it activates the C β -H bond, facilitating the enolization of the pre-oxidized 2-phenoxy-1-phenylethanone. On the other hand, through single-electron transfer involving Ce 3+ 4f 1 and the adsorption by oxygen vacancies, it enhances the oxidative cleavage of the C β-O and C α -C β bonds. This study elucidates the complex mechanistic roles of the structure and properties of Au-K/CeO 2 catalyst in the selective catalytic oxidation of lignin β-O-4 bond., (© 2024 Wiley-VCH GmbH.)

One of the main obstacles to the development of sustainable biomass feedstocks today is the research of selective hydrogenation of biomass platform compounds for the synthesis of high-value chemicals. This work reports on the synthesis of a Ni/Fe bimetallic catalyst with nitrogen-doped carbon serving as the carrier, hydrogen serving as the primary donor, and isopropanol serving as the reaction medium and serving as a secondary donor. Vanillin was catalytically hydrogenated to produce 4-methylguaiacol, a complete hydrogenation product, under a reaction temperature of 200 °C for four hours. A single product with a good yield (95.26% conversion and selectivity up to 99%) was achieved by the moderate conditions, offering a potential route for the catalytic hydrogenation of biomass platform compounds., Competing Interests: The authors declare no competing financial interests., (This journal is © The Royal Society of Chemistry.)

Deep eutectic solvents (DESs) are increasingly being recognized as sustainable and promising solvents because of their unique properties: low melting point, low cost, and biocompatibility. Some DESs possess high viscosity, remarkable stability, and minimal toxicity, enhancing their appeal for diverse applications. Notably, they hold promise in biomass pretreatment, a crucial step in biomass conversion, although their potential in algal biomass carbohydrates extraction remains largely unexplored. Understanding the correlation between DESs' properties and their behavior in carbohydrate extraction, alongside cellulose degradation mechanisms, remains a gap. This review provides an overview of the use of DESs in extracting carbohydrates from lignocellulosic and algal biomass, explores the factors that influence the behavior of DESs in carbohydrate extraction, and sheds light on the mechanism of cellulose degradation by DESs. Additionally, the review discusses potential future developments and applications of DESs, particularly extracting carbohydrates from algal biomass., Competing Interests: The authors declare no competing interests., (© 2023 The Author(s).)

Fe-based MOFs (Fe-MOFs) are deemed promising Fenton-like catalysts due to their well-developed pores and accessible active sites. However, their inferior catalytic activity, iron leaching, and low H 2 O 2 utilization always hinder their application as Fe-based MOF catalysts. In this work, we manipulated the structure of Fe-oxo nodes in MIL-88B(Fe) via a Cu I species substitution method, affording a mixed-valence (Cu-incorporated Fe-MOFs) with highly improved Fenton-like performance. It is found that the Cu I serves as a shuttle to promote transfer between Fe II /Fe III , inducing the formation of a larger amount of stable Fe II sites, which was proven by experimental and DFT calculation results. A linear relationship was observed for the Fenton-like performance and the amount of Cu I species for the catalysts. The corresponding value of the • OH formation is 2.17 eV for Cu-incorporated MIL-88B(Fe), which is significantly lower than that of MIL-88B(Fe) (2.69 eV). Meanwhile, the enriched Cu I species suppress Fe species leaching during the catalytic reaction. The Fe-ion leakage of 0.4Cu@MIL-88B is very tiny (0.01-0.03 mg/L), significantly less than that of MIL-88B (2.00-3.02 mg/L). At the same time, H 2 O 2 utilization for 0.4Cu@ MIL-88B(Fe) is 88%, which is almost 4.4 times that of pure MIL-88B(Fe). This work provides insights into the rational design of Fe-MOFs as promising Fenton-like catalysts for wastewater treatment.

Aviation fuel is high energy density and is usually produced from refinery in petroleum industry. Production of renewable aviation fuel from biomass eases pressure of carbon emission regulation. The operational processes in this study include steam stripping, hydrolysis of residues, condensation reaction unit, autoclave hydrogenation, fixed-bed hydrodeoxygenation, and oil-upgrading unit. The biomass-derived aviation fuel has a low oxygen content of 0.4 %, while its high heat value is 45.5 MJ/kg. The aviation fuel ranges from C8 ∼ C15, and rich in isoparaffins (50.4 %) while the n-paraffins have a selectivity of 12.2 % and other components are cycloparaffins (19.0 %), aromatic hydrocarbons (11.3 %), and alkenes (5.6 %). The mass yield for aviation fuel from corn stover reaches 10.6 %. This pilot study achieved production of aviation fuel from raw biomass corn stover., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Metal-oxide interaction was widely observed in supported metal catalysts, playing a significant role in tuning the catalytic performance. Here, we reported that the interaction of Ru and MnO x was able to facilitate the hydrodeoxygenation of levulinic acid (LA) to 2-butanol with a high turnover frequency (1.99 × 10 6 h -1 ), turnover number (4411), and yield (98.8%). Moreover, this catalyst was capable of removing the hydroxymethyl group of lactones and diol with high yields of products. The high activity of the Ru-MnO x catalyst was due to the strong Ru-MnO x interaction, which facilitated reduction of Ru oxide to Ru 0 and Mn oxide to Mn 2+ . The increased fractions of Ru 0 and Mn 2+ provided metal and Lewis acid sites, respectively, and therefore facilitated LA hydrodeoxygenation. A linear correlation between the hydrodeoxygenation activity of the Ru-MnO x catalyst and [Mn 2+ ]ln([Ru 0 ]) was observed.

Herein, WO x -decorated Ir/SiO 2 (W/Ir = 0.06) and HZSM-5 were coupled to selectively convert microcrystalline cellulose (MCC) into C 6 alkanes. A 92.8% yield of liquid alkanes including an 85.3% yield of C 6 alkanes was produced at 210 °C. Cellulose hydrolysis, glucose hydrogenation and sorbitol hydrodeoxygenation were integrated to produce alkanes via a sorbitol route. Ir-WO x /SiO 2 showed high performance for hydrogenation and hydrodeoxygenation reactions after hydrolysis catalyzed by HZSM-5. The intimate contact between WO x and Ir enhanced the synergistic interaction through the electron transfer from Ir to WO x . The interaction strengthened the reduction capability of Ir for hydrogenations, as well as improved the adsorption and activation of C-O bonds on reduced WO x for deoxygenations. The monotungstate WO x species provided moderate Lewis acids to cooperate with Ir to accelerate hydrodeoxygenations with alleviated retro-aldol condensation to yield more C 6 alkanes., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Renal cell carcinoma (RCC) is the third most frequent malignancy within urological oncology. Sunitinib has been used as the standard of treatment for first-line RCC therapy. Understanding mechanisms of sunitinib resistance in RCC cell is important for clinical therapy and drug development. We established sunitinib resistant RCC cells by treating cells with increasing concentrations of sunitinib and named resistant cells as RCC/SR. Lefty A, an important embryonic morphogen, was increased in RCC/SR cells. Targeted inhibition of Lefty via its siRNAs restored the sensitivity of renal resistant cells to sunitinib treatment. It was due to that si-Lefty can decrease the expression of interleukin-8 (IL-8) in RCC/SR cells. Knockdown of IL-8 abolished Lefty-regulated sunitinib sensitivity of RCC cells. Mechanistically, Lefty can regulate IL-8 transcription via activation of p65, one major transcription factor of IL-8. Collectively, our present revealed that Lefty A can regulate sunitinib sensitivity of RCC cells of via NF-κB/IL-8 signals. It indicated that targeted inhibition of Lefty might be a potent approach to overcome sunitinib resistance of RCC., (© 2021 Walter de Gruyter GmbH, Berlin/Boston.)

Novel catalytic material with high catalytic activity and hydrothermal stability plays a key role in the efficient conversion of levulinic acid (LA) to γ-valerolactone (GVL) in water. In this study, mixed oxides Al 2 O 3 -TiO 2 , Al 2 O 3 -MoO 3 and Al 2 O 3 -Co 3 O 4 were synthesized by co-precipitation using aqueous solution of NaOH as precipitant. Ru catalysts supported on mixed oxides were prepared by impregnation method and their catalytic performances were tested in the hydrogenation of LA to GVL on a fixed bed reactor. The physicochemical properties of the catalysts were characterized by XRD, H 2 -TPR, NH 3 -TPD, and BET techniques. The TiO 2 component significantly affected the acidity of the catalyst, and thus its catalytic activity for the GVL yield was affected. The desired product GVL with a yield of about 97% was obtained over the Ru/Al 2 O 3 -TiO 2 catalyst under mild conditions (WHSV = 1.8 h -1 , T = 80 °C). Moreover, the catalyst Ru/Al 2 O 3 -TiO 2 exhibited excellent thermal stability in the test period of time., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Crystal α-zirconium phosphate (α-ZrP) was prepared by a hydrothermal method and exfoliated into a layered structure by n -hexylamine (C 6 H 13 NH 2 ). Ni-based catalyst (Ni/ZrP) was promoted by loading nickel on the layered α-ZrP via ion exchange. The catalyst was performed to catalyze hydrodeoxygenation of 5-hydroxymethylfurfural (HMF) to 2,5-dimethylfuran (DMF), and a 68.1% yield of DMF and 100% conversion of HMF were achieved at 240 °C, 5 MPa H 2 , and 20 h. The DMF yield can still retain 52.8% after five cycles. The characteristics of the catalyst were investigated via N 2 adsorption-desorption, X-ray diffraction, field emission scanning electron microscopy, high-resolution transmission electron microscopy, pyridine-adsorbed Fourier transform infrared (FTIR) spectra, FTIR spectra, inductively coupled plasma mass spectrometry, and thermogravimetric analysis-mass spectrometry, as well as Raman spectroscopy. A pathway from HMF to DMF was found with MF as the intermediate product, and DMF production was preferable via the -CH 2 OH group hydrogenolysis of HMF over Lewis acidic sites of Ni/ZrP, which is caused by the zirconium vacant orbits., Competing Interests: The authors declare no competing financial interest.

Inexpensive non-sulfided Ni-based catalysts were evaluated for hydrodeoxygenation (HDO) using guaiacol as model compound. SiO2-ZrO2 (SZ), a complex oxide synthesized by precipitation method with different ratio of Si/Zr, was impregnated with Ni(NO3)2·6H2O and calcined at 500°C. Conversion rates and product distribution for guaiacol HDO at 200-340°C were determined. Guaiacol conversion reached the maximum at 300°C in the presence of Ni/SZ-3. When HDO reaction was carried out with real lignin-derived phenolic compounds under the optimal conditions determined for guaiacol, the total yield of hydrocarbons was 62.81%. These hydrocarbons were comprised of cyclohexane, alkyl-substituted cyclohexane and alkyl-substituted benzene. They have high octane number, would be the most desirable components for fungible liquid transportation fuel., (Copyright © 2013 Elsevier Ltd. All rights reserved.)