Lignin valorization is often limited by the lack of predictive models for predicting solvent effects, making solvent selection a critical yet challenging task. This study attempts to bridge the gap by developing quantitative models that can accurately predict lignin conversion efficiency based on fundamental solvent parameters. Lignin conversion is primarily governed by the solvent's hydrogen-bond accepting capacity (acceptor number, AN) and polarity (E-T), rather than physical solubility (Relative Energy Difference, RED) calculated from Hansen Solubility Parameters (HSP). High accuracy (adjusted R-2 > 0.97) is achieved in predicting lignin conversion using these correlations. It is also found that solvent molecular structure dictates the product distributions: short-chain alcohols (e.g., methanol, ethanol) maximize monomeric phenol yield as they can serve as effective capping agents, whereas longer-chain alcohols generate diversified products as they promote solvent-derived side reactions. In summary, this work establishes a quantitative framework for rational selection of solvent in lignin hydrothermal liquefaction, which guides the design of efficient solvent systems for lignin valorization to obtaining phenolic monomers.

As sustainable alternatives to fossil fuels, biomass-derived liquid fuels play a critical role in mitigating greenhouse gas emissions and diversifying energy supplies. In this study, the effect of calcination temperature (600-1000 degrees C) on the structure and catalytic performance of MnFeCoNiCu/activated carbon (AC) catalysts via in-situ carbon reduction method for the hydrodeoxygenation (HDO) of fatty acid methyl esters (FAME) to sustainable biofuels including bio-jet fuel and green diesel was systematically investigated. Results revealed that increasing calcination temperature promoted the transformation of the crystal structure from body-centered cubic (B2) to face-centered cubic (FCC), with the AC-900 catalyst (calcined at 900 degrees C) exhibiting a dominant FCC phase, enhanced metal dispersion, and optimal surface defect density. Although higher temperature reduced the specific surface area and pore volume of the AC support, the formation of a stable multimetallic solid solution and strong metal-support interactions at 900 degrees C significantly improved catalytic performance. Under optimal reaction conditions (350 degrees C, 0 MPa H-2, 2 h), the AC-900 catalyst achieved 100% FAME conversion and 97% hydrocarbon selectivity, primarily via decarbonylation/decarboxylation (DCN/DCX) pathways, favoring the production of C-15-C-17 hydrocarbons aligned with green diesel and bio-jet fuel specifications. Increasing H-2 pressure favored alkane formation by promoting olefin hydrogenation, while lower pressure enhanced C-C bond cleavage for shorter-chain hydrocarbons. Circulating stability tests indicated that the AC-900 catalyst maintained 62% FAME conversion and >80% hydrocarbon selectivity after 5 cycle. This work highlights the critical role of calcination temperature in tailoring FCC-structured multimetallic catalysts for efficient FAME conversion, providing insights into the rational design of stable, high-performance catalysts for sustainable biofuel production.

The selective hydrogenation of furfural (FFA) to furfuryl alcohol (FAL) is one of the key reactions in the highvalue utilization of biomass. The development of non- precious metal-based catalysts with high selectivity and excellent stability holds great significance. A bimetallic nickel-molybdenum catalyst with metal nanoparticle encapsulated in carbon nanotubes (NiMo@CNT/C) is synthesized via catalytic chemical vapor deposition (CCVD), and its catalytic performance for the selective hydrogenation of FFA to FAL is systematically studied. Under optimized conditions (80 degrees C, 15 bar H2, and 3 h, methanol as solvent), the catalyst achieves 100% FFA conversion and 94.79% FAL selectivity, outperforming other supported catalysts for the same reaction. The NiMo@CNT/C catalyst exhibits good catalytic stability, maintaining complete FFA conversion and 92.52% FAL selectivity after 6 consecutive reaction cycles without structural degradation. The distinct catalytic activity originated from the synergistic effects of CNT encapsulation-induced metal anchoring, strong Ni-Mo bimetallic interaction with electron transfer, high graphitization for enhanced electron transfer, and well-balanced textural/acidic properties. Moreover, the catalyst shows good substrate versatility for the selective hydrogenation of various carbonyl- and nitro-containing compounds, providing a promising green catalyst design strategy for the conversion of biomass-derived platform compounds.

Actualizing mass production of high-performance Ni-based nanocatalysts and industrial-scale HER catalysis via AEMWE is significant yet challenging. Herein, we develop a scalable method to generally produce Ni/NiO@RE2O3/C with 500 g-scale for unprecedented HER catalysis of AEMWE. The hetero-structured Ni/NiO@La2O3/C consists of fcc Ni metal as the core, fcc NiO as the sub-surface layer and bcc La2O3 adhered on the local surface. Its remarkable HER performance of 32 mV overpotential at 10 mA cm-2 and 29.2 mV dec-1 Tafel slope is significantly better than those of Pt/C, Raney Ni, Ni/NiO/C and other Ni/NiO@RE2O3/C. More importantly, it can realize industrial-scale current densities of 1 A cm-2 and 2 A cm-2 at 1.6 V and 1.7 V for AEMWE, respectively, exceeding the U.S. DOE's target in 2025 specifications, along with a long-term lifetime of 250 h with voltage decay rate of only 76 μV h-1, demonstrating a large potential for industrial-scale AEMWE application.

A new method for preparing carbon nanotubes by loading metal nickel onto pretreated bamboo powder as a catalyst support is explored in this work. The catalysts are prepared by wet impregnation method using bamboo powder pretreated with seven reagents as the support and nickel as the active metal. The carbon nanotubes are successfully prepared using the traditional chemical vapor deposition method and CH4 as the carbon source. The quality of carbon nanotubes prepared by pretreating bamboo powder with acid (H3PO4, HCl, H2SO4, HNO3) was superior to that of alkali (Na2CO3, NaOH, KOH). Among them, the carbon nanotubes prepared using nitric acid pretreated bamboo powder as a support exhibit the best quality (ID/IG = 0.48) and the highest carbon yield (337 mg/g). The effect of metal nickel loading (1 wt%, 2 wt%, 3 wt%, 5 wt%, and 10 wt%) is further studied. Excessive or insufficient nickel content can reduce the quality and yield of carbon nanotubes. When the metal nickel loading is fixed at 5 wt%, the quality of the prepared carbon nanotubes is superior to other nickel loadings and follows the tip growth mechanism.

The production of bio-jet fuel via the hydrodeoxygenation (HDO) process of lipids emerges as a highly promising strategy for alleviating environmental pollution within the aviation sector. However, conventional catalysts typically require complex preparation procedures and depend on high pressure hydrogen, thereby increasing production costs and limiting their widespread application. This study presents a novel one-step in-situ preparation of nickel-iron (Ni/Fe) bimetallic catalysts supported on carbon, specifically designed to enable efficient bio-jet fuel production under solvent-free and low hydrogen pressure conditions. Using methyl palmitate (MP) as a model feedstock, the effects of Ni/Fe ratio, reaction temperature, hydrogen pressure, and Ni/ZSM-5 addition on the hydrodeoxygenation conversion and bio-jet fuel selectivity were systematically investigated. Remarkably, the NiFe/C catalyst optimized with a Ni/Fe ratio of 1:1 demonstrated extraordinary performance, attaining a complete conversion of 100 % and high selectivity of 97 % towards bio-jet fuel at 375 degrees C and a relatively modest 2 MPa hydrogen pressure. Despite a moderate decrease in conversion (to 53.65 %) and selectivity (to 83.06 %) after five cycles- attributed to carbonaceous deposition-the NiFe/C catalyst demonstrated robust durability and exceptional versatility with respect to different feedstocks. Decarboxylation (DCX) and decarbonylation (DCN) were identified as the dominant reaction pathways in the NiFe/C-catalyzed hydrodeoxygenation process. Notably, combining NiFe/C with Ni/ZSM-5 enriched product composition with aromatic hydrocarbons, isoalkanes, and cycloalkanes, thereby improving the overall quality of the bio-jet fuel. This innovative approach provides a cost-effective and high-efficiency pathway for the advancement of bio-jet fuel preparation technology.

To fully utilized the high value-added phenolic compounds in biomass pyrolysis bio-oils, a heterogeneous extraction method was developed in this study to separate 4-ethylguaiacol, guaiacol, and eugenol from bio-oil one by one. Based on the high selectivity of coordination intermediates generated between Ca2+ 2+ and phenolic compounds with hydroxyl and methoxy groups towards the parent phenol, the reaction intermediate between each of 4-ethylguaiacol, guaiacol, eugenol and Ca2+ 2+ was used as the extracting agents. Influencing parameters investigated were the sequence of extracting three phenolic compounds from the model bio-oil, the optimal extraction conditions, and the Ca2+ 2+ distribution in the original extracting agents at the end of the reaction. The optimal extraction sequence was determined to be 4-ethylguaiacol, eugenol and guaiacol through the evaluation of multiple experiments changing their addition sequence. Under the conditions of 25 degrees C reaction temperature, 45 min reaction time, and pH value of 7, the extraction efficiency of 4-ethylguaiacol, eugenol and guaiacol from bio-oil reached 60.6 %, 46.1 % and 60.7 %, respectively. Meanwhile, the purity of these three phenolic compounds achieved 62.4 %, 90.0 % and 89.0 %.

The ever-increasing global energy demand and growing environmental concerns have underscored the significance of biomass utilization. Catalytic pyrolysis of biomass, especially cellulose, into value-added chemicals and liquid fuels presents a sustainable solution. Herein, Au/TS-1 catalysts modified with four alkali metal carbonates (Na, K, Rb and Cs) were synthesized and evaluated on-line in cellulose catalytic pyrolysis. The results reveal that alkali modification impacts the structural properties of catalyst. It leads to a reduction in the relative content of framework titanium, modifies the pore structure (decreases specific surface area and converts micropores to mesopores), alters the acid site distribution (introduces medium-strong acid sites), and affects the Au particle dispersion (enhances dispersion and reduces particle size). In catalytic activity tests, alkali-modified Au/TS-1 catalysts exhibited enhanced performance. Notably, Rb-Au/TS-1 and Cs-Au/TS-1 showed significant increases in the selectivity for oxygen-containing compound. Specifically, furan selectivity is enhanced upon modification with Rb and Cs, while Na and K promote carbon chain cyclization in ketone formation. Moreover, aldehyde compounds are newly generated after the modification process. This study provides valuable insights for optimizing alkali-modified Au/TS-1 catalysts in cellulose catalytic pyrolysis, thereby facilitating the conversion of biomass-to-chemicals and liquid fuels.

Biomass, as a renewable resource, holds great significance in its conversion into valuable chemicals or fuels, representing a crucial avenue for its utilization. Nevertheless, catalytic pyrolysis currently faces constraints, demanding further enhancements in both the selectivity of target products and the recyclability of catalysts. Herein, we reported an innovative in-situ combined with ex-situ catalytic pyrolysis strategy by using red mud loaded with cobalt (Co/RM) and activated carbon (AC) as the catalyst for this combined catalytic pyrolysis system. By optimization of process conditions, the selectivity of furans was further improved significantly. The results showed that with a combined catalytic system constituted of Co/RM and Co/RM + AC, under conditions of a pyrolysis temperature of 400 degrees C, a catalytic temperature of 500 degrees C, and a mass ratio of catalyst to raw material of 20:1, the selectivity of furans can be increased to 80.1 %. Remarkably, this combined catalytic system exhibits excellent catalytic activity for furans production even after 20 cycles of operation. Moreover, the established combined catalytic system is capable of converting tobacco, bamboo, and wood into furans with more than 100 % increasement. These results suggest that this novel strategy harbors broad application prospects and has the potential to catalyze more efficient exploitation of biomass resources.

The paper presents the design of an electrocatalyst named Mo-Pt/Ni-CNTs, which combines the advantages of strong metal-support interaction and the synergistic effect of active sites. In a three-electrode electrochemical measurement, the Mo-Pt/Ni-CNTs demonstrates a lower overpotential of 29.2 mV at 10 mA cm- 2, and a favorable Tafel slope of 33.7 mV decade- 1 in comparison to Pt/C catalyst in 1.0 M KOH. Furthermore, the anion exchange membrane water electrolyzer cell achieves a low cell voltage of 2.41 V at 2 A cm- 2 (in 1.0 M KOH solution at 80 degrees C). In-situ Raman analysis and DFT calculations reveal that introducing Mo atoms into the Pt sites and loading them onto the special carbon nanotubes, which are wrapped nickel (Ni-CNTs), can not only change the Pt valence state and electrical structure, but also form the strong metal-support interactions between Mo-Pt nanoparticles and Ni-CNTs.

One-step synthesis of an armoured catalyst featuring an ordered carbon layer-coated FeCoNiCuZn high-entropy alloy was reported for the catalytic reforming of biomass pyrolysis volatiles to produce renewable hydrogen. The prepared catalysts were characterized in detail by multiple techniques to reveal the features of the ordered carbon layer and the distribution of the high-entropy alloy. Response surface-centred combinatorial design (RSM-CCD) was employed to optimize the process conditions for hydrogen production from the catalytic pyrolysis of poplar wood sawdust. The results indicated that the FeCoNiCuZn-800 catalyst exhibited the best performance, and its unique structure contributed to an enhanced hydrogen yield. The enhanced catalytic performance stems primarily from the multi-element synergy within the HEA. Furthermore, the mesoporous structure facilitates mass transport, while the ordered carbon layers suppress nanoparticle agglomeration and promote electron transfer. The optimized process conditions were a pyrolysis temperature of 515 degrees C, a catalytic temperature of 622 degrees C, and a catalyst quality of 0.623 g. Under these conditions, the maximum hydrogen yield reached 40.10 vol% and 12.80 mmol & sdot;g-1biomass-daf, demonstrating the great potential of this catalyst in the field of renewable hydrogen production.

This paper proposes a novel method to synthesize high-value multi-walled carbon nanotubes using inexpensive and readily available pine sawdust with nitric acid pretreatment as nickel catalyst supports. In the process of preparing carbon nanotubes using the traditional chemical vapor deposition method, it was found that nitric acid pretreatment of pine sawdust can significantly improve the yield and quality of carbon nanotubes. After the pretreatment of pine sawdust with nitric acid, the specific surface area, pore volume and pore size of the fresh catalysts all increased to a certain extent, and the particle size of Ni particles decreased. Meanwhile, the interaction force between nickel particles and pine sawdust significantly weakened. Furthermore, the parameters affecting the quality of carbon nanotubes, such as soaking time (0-48 h) in nitric acid and temperature (25-100 degrees C), and nickel content (2.5-10.0 wt%) in the catalyst, were also studied to seek the optimal pretreatment parameters. The nitric acid treatment of the catalyst support significantly improved the quality of carbon nanotubes, characterized by a slender and smooth morphology, smaller diameter (33.61 nm), fewer tube walls (26 layers), higher thermal stability, graphitization degree (ID/IG = 0.459), and carbon yield (311 mg/gcat).

This paper explores the feasibility of directly using natural cellulose fibers (CF) with uniform microstructure as catalyst supports to prepare carbon nanotubes (CNTs). Six different Ni-based catalysts are prepared using CF, lignin, biochar, activated carbon, Al2O3, and ZSM-5 as supports and used for CNTs growth. The reaction conditions including the growth temperature (600-800 degrees C) and the metal loading (1-9 wt%) are studied for promoting the synthesis of high-quality CNTs. When the metal loading and the growth temperature are fixed at 5 wt % and 750 degrees C, the highest degree of graphitization (ID/IG=0.74) and carbon yield (2080 mg/gcat) are achieved on Ni/CF due to the optimal interaction between the metal and the support. The CNTs deposited on Ni/CF catalysts during methane decomposition mainly follow a tip growth mechanism. The catalytic performance of Ni-based catalysts on CF is superior to that of Fe- and Co-based catalysts, which is beneficial for CNTs graphitization.

Several Rh-based La2Zr2O7 type catalysts promoted by the transition metals (Mn, Fe, and Co respectively) were synthesized and used to reform n-hexadecane (a diesel surrogate) that contains 50 ppm dibenzothiophene for hydrogen production. Compared to Co-LaZrRh and Mn-LaZrRh, the Fe-LaZrRh catalyst exhibited the best hydrogen extraction capability and sulfur tolerance. This is probably due to the introduction of Fe, which not only enhances the Rh dispersion, but also facilitates the formation of electron-deficient Rh sites and the generation of oxygen vacancies. Additionally, electron-deficient Rh sites can hinder the formation of an irreversible sulfur-metal bond, thus resulting in better sulfur tolerance and thermal stability. Finally, the generated oxygen vacancies may also activate steam to form surface active oxygen species, which help remove the deposited carbon on the catalyst surface. In summary, the developed Fe-LaZrRh catalyst performed the best in the steam reforming of n-hexadecane containing 50 ppm sulfur, which deserves further exploration for future applications.

With ammonia playing a more and more vital role in serving as a renewable hydrogen carrier, it is critical to develop economical and efficient electrocatalysts for the ammonia oxidation reaction (AOR) in which hydrogen is released. In this work, a heterostructured electrocatalyst, Ni3S4@NiCo2O4/NF, was synthesized using the hydrothermal method for the purpose of improving AOR efficiency. The obtained nano catalyst exhibited an excellent AOR activity (10 mA.cm(2) at 0.58 V vs. Hg/HgO) and stability (37.2 h at 100 mA.cm(2)). XRD and XPS characterizations indicated that the bulk catalyst remained unchanged yet with surface metallic Ni oxidized. In situ Raman spectroscopy analysis further revealed that the heterostructured catalyst underwent an obvious surface reconstruction process (Ni(OH)(2) -> beta-NiOOH -> gamma-NiOOH) which accordingly lowered the potential required for reconstruction and optimized the energy barrier for the AOR. DFT calculations showed that the heterostructured catalyst not only favors the acceleration of the reconstruction process due to electronic interactions, but also reduces the energy barrier in *NHNH2 generation step, thus enhancing the performance of AOR, which is superior to the other two catalysts. The product gas analysis showed that the developed catalyst maintained an excellent Faraday efficiency of 95% and a continued activity. In summary, this work opened a potential new pathway for the design of heterostructured electrocatalysts for H-2 production through AOR.

BACKGROUND: During the pulping and bleaching processes, 4-chloroguaiacol accounts for a large proportion of chlorine containing pollutants. In this study, a heterogeneous extraction method for extracting 4-chloroguaiacol from the bleaching wastewater by using the intermediate as the solid phase extraction agent is proposed.RESULTS: The solid intermediate with the molar ratio of 4-chloroguaiacol to calcium 2:1 is firstly prepared. It is used for reacting with the crude 4-chloroguaiacol in the bleaching wastewater to generate the end solid complex with the molar ratio of 4-chloroguaiacol to calcium 4:1. It is verified to be that the high-purity 4-chloroguaiacol can be released from the simple thermal decomposition of the end solid complex.CONCLUSION: At an optimum extraction condition including 30 degrees C reaction temperature, the pH value of 7, using the deionized water as the solvent, the extraction yield and the purity of 4-chloroguaiacol reached 89.2% and 97.8%. Furthermore, after 15 cycle extraction times, the extraction rate of 4-chloroguaiacol can still reach 86.3%. The extraction yield and the purity of 4-chloroguaiacol reached 68.15% and 99.56% when the guaiacol content was lower than 25 mg/L at the bleaching wastewater.(c) 2023 Society of Chemical Industry (SCI).

The conversion of non-edible oils such as fatty acid methyl esters (FAME) into green and renewable liquid fuels align with the current trend of sustainable development. However, traditional processes often involve multi-step process to prepare catalyst and require high-pressure hydrogen. This study reports a strategy for the in-situ preparation of MnFeCoNiCu/C catalyst, enabling the one-step conversion of FAME into bio-jet fuels and hydrocarbon-based diesel under solvent-free and low-pressure conditions. The effect of active metal loading, reaction temperature, hydrogen pressure, and ZSM-5 zeolite addition on the catalytic performance was investigated. Under the conditions of reaction temperature 350 degree celsius and hydrogen pressure 2 MPa, the conversion rate of FAME reaches 100%, and the selectivity of bio-jet fuel and green diesel is 48.35% and 51.05%, respectively. A small number of olefins, cycloalkanes, and aromatics can also be detected in the products. After the 4 cycles of AC-15 catalyst, the selectivity of bio-jet fuel and diesel are 40.09 % and 39.81 %, respectively. The above research work provides a mild and efficient method for the preparation of renewable bio-jet fuel and green diesel.

In this paper, a novel low-cost process for preparing carbon nanotubes (CNTs) by loading transition metals (Fe, Co, Ni) on carbon materials (pine sawdust) is investigated. Among three metal catalysts, nickel catalyst exhibits the best catalytic performance including the highest carbon yield (23.8 wt%) and the best quality of the grown CNTs (ID/IG = 1.01). Meanwhile, the nickel content of 2.5 wt% was confirmed to be the most suitable metal content for CNTs growth. Based on the prepared CNTs with pine sawdust as the catalyst support, the two-step method and the one-pot method were proposed. In the two-step method, the Ca(OH)2 powder as a reactive assistant and the introduction of CO2 can obtain CNTs with the least defects and the highest purity. The comparative experiments show that the mere introduction of CO2 without any reactive assistants will cause greater damage to CNTs. In the one-pot method, the addition of Ca(OH)2 improves the quality and thermal stability of CNTs, which verifies the feasibility of the one-pot method reported in this study.

Production of valuable chemicals and fuels from waste animal fat and vegetable oils can serve as alternatives to fossil energy. In this study, the selective production of alkanes and higher fatty alcohol via hydrodeoxygenation (HDO) of palmitic acid over red mud-supported nickel catalysts (Ni/RM) was reported. Meanwhile, the study has investigated the effect of Ni loading, reaction temperature, hydrogen pressure on the HDO of palmitic acid, analyzed the reusability of Ni/RM and explored the possible reaction mechanism. The results show that palmitic acid is completely converted over 7%Ni/RM. The selectivity of fatty alcohol and alkanes are 92.54% (260 degrees C) and 100% (300 degrees C), respectively. Ni/RM has shown the highest catalytic performance as compared to commercial Ni/SiO2 and Ni/gamma-Al2O3 catalysts. The 7%Ni/RM also demonstrates stable catalytic performance after multiple times of reuse. Moreover, hexadecanol plays an important role in hydrodeoxygenation, decarbonylation, and decarboxylation routes.

Using carbon-based materials as substrates or additives is an effective strategy for the improvement of electrochemical properties of polypyrrole (PPy) in supercapacitors, while the interfacial interactions between them is not exactly clear, which limits the rational design of composite electrodes. Herein, the interfacial interactions are investigated by forming novel freestanding composite electrodes via depositing PPy on the surface of carbon foam (CF). After combination, the capacitance increases from 37.3 mF cm(-2) to 364.0 mF cm(-2) . Moreover, a superior capacitance retention (99.6%) can be achieved, after 10,000 charging/discharging cycles. Density functional theory (DFT) results show that the introduction of different oxygen-containing functional groups will lead to the difference of adsorption energy between carbon materials and PPy, thus affecting the cycling stability of composite materials. Moreover, the intermolecular interaction also affects redox properties of composite electrodes by changing the composition and energy of frontier orbits of the interfacial complexes involved in redox reactions. This study will provide a new perspective for purposeful regulating the electrochemical performance of composite electrodes.