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Abstract An Al3+-modified formaldehyde-p-hydroxybenzenesulfonic acid resin catalyst (Al-SPFR) was synthesized through a hydrothermal method. N 2 adsorption–desorption experiment and acid–base titration revealed that the Al-SPFR catalyst had better texture properties and higher strong acid content than the previously prepared unmodified SPFR. The effects of reaction time and temperature, catalyst loading, and water content in water/GVL mixture were investigated for glucose dehydration using Al-SPFR as the catalyst. An HMF yield of 47.4% was obtained at 170 °C for 2 h in the biphasic GVL/H 2 O medium. Further performing a five-cycle experiment, the HMF yield initially decreased and then remained fairly constant, and the recyclability of the Al-SPFR was reasonable. Graphical abstract Unlabelled Image Highlights • An Al3+ modified PHSA-formaldehyde resin acid was successfully prepared. • Introducing Al3+ into PHSA-formaldehyde resin improved its texture properties. • Al3+ modified resin exhibited better performance for glucose-HMF conversion. • An optimal HMF yield of 47.4% was obtained at 170 °C for 2.0 h in GVL/H 2 O. [ABSTRACT FROM AUTHOR]

[Display omitted] • Attapulgite-based MCM-41 zeolite supported Ni-Nb catalysts were manufactured. • L-lysine addition increased the void structures and specific surface area of LAMZ. • Nb addition improved catalyst reducibility, surface acidity and metal dispersion. • 5Ni-1Nb/LAMZ exhibited excellent anti-coking and anti-sintering properties. • 5Ni-1Nb/LAMZ could maintain high activity during 55-hours AASR reaction. Acetic acid steam reforming (AASR) was generally considered as one of the promising technologies for hydrogen production. In this work, the L-lysine-assisted attapulgite-based MCM-41 zeolite (LAMZ) was successfully synthesized by using attapulgite-derived silicon source and the LAMZ-supported Ni-Nb (xNi-yNb/LAMZ) catalysts were prepared via conventional impregnation method. The effects of LAMZ and Nb content on regulating the microstructures and properties of Ni-based catalysts were investigated by various characterizations. Results revealed that the addition of L-lysine could contribute to forming more void structures and increasing specific surface area of LAMZ support, which was beneficial for promoting the dispersion of active sites and enhancing the metal-support interaction. Additionally, Nb optimized the reduction of Ni, increased the concentration of surface-active Ni species, improved the strength of surface Lewis acid and promoted the formation of Ni-NbO x interfaces. Amongst, 5Ni-1Nb/LAMZ exhibited the highest surface Ni0 sites and Ni-NbO x interfaces, which further induces the generation of V O generation and the flow of lattice oxygen. Therefore, the 5Ni-1Nb/LAMZ catalyst presented the highest acetic acid conversion (82.1 %) and hydrogen yield (69.9 %) at reaction conditions of reaction temperature = 750 °C, S/C = 3, WHSV = 19.96 h−1, furthermore, it almost no any inactivation during 55 h of AASR. Additionally, the characterization results of spent catalysts confirmed that 5Ni-Nb/LAMZ possess high coke resistance and anti-sinter capability. [ABSTRACT FROM AUTHOR]

Converting cellulose (Cel) into ethyl levulinate (EL) is one of the promising strategies for supplying liquid fuels. In this paper, the prepared sulfonated P-W-modified N-containing carbon-based solid acid catalyst (PWNCS), in which the Polyaniline (PANI) was employed as N and C precursors, successfully converted Cel into EL under the water-ethanol medium. The characterization results demonstrated that a tiny addition of P increased the Brønsted acid sites (BAS) content and defective WO 3 provided the Lewis acid sites (LAS), meanwhile, the sulfonation process did not change the fundamental structure but introduced the sulfonic groups to dramatically increase the acidic content. Therefore, under optimized reaction conditions, PWNCS realized about 100% Cel conversion and 71.61% of EL yield, furthermore, the selectivity of EL reached 89.14%. In addition, the effect of water on the reaction pathway of Cel to EL over PWNCS was proposed. The addition of water generally resulted in the hydration of defective WO 3 to reduce the LAS and increase BAS, which significantly inhibited the side reactions of retro-aldol condensation (RAC) and subsequent etherification reactions during Cel conversion and then improved the selectivity of EL. [Display omitted] • One-pot conversion of cellulose to ethyl levulinate under water-ethanol was achieved. • Sulphonated P-W modified carbon-based solid acid catalysts were prepared. • PWNCS exhibited 99% of cellulose conversion and 71.61% of ethyl levulinate yield. • Reaction pathways for the cellulose conversion into EL over PWNCS were proposed. [ABSTRACT FROM AUTHOR]

Molten salt hydrates (MSHs) are remarkable in breaking through the recalcitrant structure of microcrystalline cellulose and raw biomass. After being pretreated in 60 wt% LiBr at 130 °C for 2 h, cellulose crystallinity as well as degree of polymerization (DP) decreased. It was found that 91.3% yield of pretreated cellulose was removed from MSHs by filteration followed by being hydrolyzed into glucose with a high yield of 75.3% by dilute acid under mild reaction conditions. The pretreatment process also works on raw corn stover hydrolysis. After being pretreated at 100 °C for 5 h, 88.4% yield of cellulose in biomass was recovered and can be hydrolyzed into 54.9% yield of glucose with dilute acid. It was found that the cellulose in corn stover can be easier degraded compared with microcrystalline cellulose during MSHs pretreatment, which dues to the formation of acetic acid from hemicellulose hydrolysis. The proposed pretreatment technique presents a promising potential for glucose production from biomass in a commercial way. Unlabelled Image • MSHs pretreatment effectively decreased cellulose crystallinity and DP. • After being pretreated at 130°C for 2 h, 91.3% of cellulose was removed from MSHs via filtration. • Enhanced glucose yield of 75.3% was obtained from pretreated cellulose hydrolysis at mild condition. • 88.4% cellulose recovery and 54.9% glucose yield were obtained from MSHs pretreatment and hydrolysis, respectively. [ABSTRACT FROM AUTHOR]

Catalytic steam reforming for hydrogen production was a viable tar removal technology. The key issue of catalytic steam reforming of toluene (tar model) for hydrogen production (CSRT) was the devise and development of advantageous catalysts. In this work, attapulgite-based titanosilicate zeolite (ATS) supported Ni-based catalysts was prepared and applied into CSRT. In addition, compared with the attapulgite (ATP), attapulgite-derived silicon source (HTP) and commercial TiO 2 , the effects of four different supports over the catalytic performance of Ni-based catalysts for CSRT were further investigated. The structural characteristics of the prepared catalysts were revealed by various characterization methods. Amongst, N/ATS appeared the highest toluene conversion (90.71%) and H 2 yield (63.57%) during 4 h of CSRT reaction, which mainly attributed to its highest surface Ni0 molar ratio. Additionally, N/ATS revealed unique resistance to carbon deposition under harsh reaction conditions. This was mainly due to the synthesized ATS had larger BET and the highest hierarchical factor (HF) of pore structure which better promoted mass and heat transfer and its unique nanocluster assembled lamellar structure better anchoring the Ni metal and inhibited sintering, while its superior dispersion of weak acidic sites resulted in less carbon deposits. This work provided a probability for the preparation of economical attapulgite-based heteroatom zeolite to support Ni for hydrogen production via steam reforming of biomass-based oxygenates. [Display omitted] • Attapulgite-based titanosilicate zeolite (ATS) with highest HF value was prepared. • ATS supported Ni-based catalyst (N/ATS) was applied for H 2 production for CSRT. • N/ATS had superior catalytic ability due to its highest Ni0 ratio and unique porosity • The lamellar structure of N/ATS effectively anchored the active metallic Ni. • The highest weak acidic sites of N/ATS observably reduced the carbon deposits. [ABSTRACT FROM AUTHOR]

• NiMo-Pi is obtained via a one pot hydrothermal reaction. • This self-supported cathode shows enhanced water reduction activity. • It responses quickly and robustly in a wide current range. • In-situ reconstruction of its surface enables high stability. Solar power drived water splitting for hydrogen production is pivotal for sustainable energy conversion. Yet, it is challenging to develop earth abundant, high active, and durable electrodes to catalyzing hydrogen evolution reaction (HER) under fluctuating solar electricity. Herein we report self-supprted NiMo phosphate (NiMo-Pi) electrodes, where amorphous NiMo-Pi with nanosheets-like structure grow directly on conductive Ni foam by a facile one-step hydrothermal treatment. The electronic structures of Ni and Mo are tuned by O and P in NiMo-Pi electrodes, resulting the down-shift of their d -band centers. NiMo-Pi electrodes offer high activity and stability for HER, delivering -100 and -500 mA cm−2 mg cat −1 with overpotentials of 343 and 461 mV, repectively. They also sustain long-term electrolysis at a constant industrial-level current density of 500 mA cm−2 and at dynamic current densities ranging from -10 to -1 000 mA cm−2. Their HER activity become higher after stability tests, benefitting from in-situ surface reconstruction. This reconstruction makes the surface rich in active higher-lying d -band centers. This work suggests that tuning the electronic structure of electrodes is an efficient way to design efficient and stable electrodes for HER under harsh conditions. [Display omitted] [ABSTRACT FROM AUTHOR]

2, 5‐Furandicarboxylic acid (FDCA) obtained from selective 5‐hydroxymethyfufural (HMF) oxidation is an important biodegradable polyester monomer and its production strongly depends on homogeneous base additives. The production of FDCA over solid base catalyst is green and environment‐friendly. Herein, Au/Mg(OH)2 as the metal‐solid base catalyst, was prepared by a simple colloidal method and applied to the oxidation of HMF. Detailed characterizations (XRD, TEM, XPS, TGA, CO2‐TPD, etc.) were performed to uncover the structure‐activity relationship of the catalyst. 92.6 % yield of FDCA was achieved under the optimal reaction condition. Moreover, a plausible mechanism for HMF oxidation over the metal‐solid base catalyst was proposed by combining the surface properties of catalyst with the oxidation reaction results. [ABSTRACT FROM AUTHOR]