Conversion Products Research Articles

Investigations of Mechanisms Leading to Capacity Differences in Li/Na/K-Ion Batteries with Conversion-Type Transition-Metal Sulfides Anodes.

Conversion-type transition-metal sulfides (CT-TMSs) have been extensively studied as the anode of Li/Na/K-ion batteries due to their high theoretical capacity. An issue with the use of the material in the battery is that a large capacity difference is commonly observed. However, the underlying mechanism leading to the problem is still unknown. Here, the large capacity difference mechanisms of CT-TMSs anodes in the Li/Na/K-ion storage are elucidated, which arises from the difference in conversion degree and size of conversion products. Specifically, the increase in ionic radius will cause the increase in insertion-reaction ion diffuse energy barrier and conversion-reaction Gibbs free energies of phase transformation to decrease reaction kinetics, which causes a decrease in conversion degree and an increase in size of conversion products, thus leading to reduction in capacity. The increase in size and the decrease in the amount of conversion products inevitably reduce the amount of spin-polarized electrons injection into Fe and corresponding ions storage amount into sulfides during the ion-electron decoupling storage, thus reducing the capacity. The research clarifies the capacity difference mechanisms of CT-TMSs anodes in Li/Na/K storage, providing valuable insights for designing Li/Na/K storage high-capacity anodes.

Biofilm mass transfer and thermodynamic constraints shape biofilm in trickle bed reactor syngas biomethanation

Syngas (H2, CO2, CO) produced thermochemically from lignocellulosic biomass is an underexploited source for resource recovery and valorisation through its biological conversion for the production of a wide range of chemicals and fuels. Syngas biomethanation is one such promising bioconversion pathway, displaying interesting features such as high conversion efficiency and product selectivity, as methane is the sole product of the process. The biological conversion of syngas to high purity biomethane is still typically associated with a number of challenges related to the syngas composition, CO toxicity, and gas–liquid mass transfer limitations. In this work, the syngas biomethanation process carried out in trickle bed reactors was investigated at its boundary conditions to explore the limits of the process, focusing on syngas composition and mass-transfer conditions potentially limiting process performance. The process was found to be robust when exposed to CO excess, but highly sensitive to H2 excess, which caused severe inhibition even under small amounts of excess H2. This implies that biomethane purity comparable to natural gas can be achieved by addition of renewable H2, but this requires precise control to avoid process failure. Modulating the liquid recirculation rate and gas residence time allowed for a maximum methane productivity of 9.8 ± 0.5 mmol CH4 h−1 Lreactor−1 with full conversion of H2 and CO at a gas residence time of 1 h. Nevertheless, increasing the gas–liquid mass transfer with increasing liquid recirculation rate did not lead to increased methane productivity, which suggested additional rate-limiting bottlenecks in the process. Careful investigation of other factors potentially limiting the process led to the conclusion that diffusive transport of syngas components in the biofilm was the main bottleneck of the process. This diffusive limitation leads to a scenario of severe substrate scarcity in the biofilm phase that conditions the thermodynamic feasibility of the different biochemical reactions involved in syngas biomethanation. In turn, these thermodynamic constraints were found to drive the stratification of microbial groups and sequential consumption of syngas components along the height of the reactor

C/N conversion and pigment production of Blastochloris sulfoviridis characterized by bacteriochlorophyll b under near-infrared single-wavelength laser

High carbon use efficiency (CUE) of photosynthetic bacteria (PSB) can concurrently increase biomass and reduce CO2 emissions. In the PSB study, light-oxygen conditions are crucial factors influencing the growth of these bacteria. Bacteriochlorophyll (BChl) b (absorption spectra: 970–1040 nm), due to its unique absorption spectrum, can be considered a crucial complement to BChl a (absorption spectra: 780–890 nm). We investigate the effects of four light-oxygen conditions on biomass, C/N conversion, and pigment production using five individual light sources in Blastochloris sulfoviridis (B. sulfoviridis), producing BChl b, isolated using 940±10 nm laser unexpectedly. Biomass, CUE, and pigment production follow the order under different light-oxygen conditions: light-anaerobic > light-aerobic > dark-aerobic > dark-anaerobic. The maximum biomass (1386.88 mg/L), highest CUE (0.95 g-biomass/g-CODremoved and 0.49 g-biomass carbon/g-CODremoved), and highest pigment production are observed under full spectrum (40 W)-anaerobic, 940-anaerobic, and 850-anaerobic conditions, respectively. Compared to light-aerobic, the nitrogen-fixing ability of B. sulfoviridis is enhanced under light-anaerobic conditions. This study contributes to research on resource recovery and greenhouse gas emissions reduction in PSB wastewater treatment.

Investigating Pt/Pumice catalyst for efficient 3-methyl-1-butanol conversion

The objective of this study was to obtain a modified Pt/pumice catalyst to support the conversion reaction of 3-methyl-1-butanol under specific reaction conditions. To achieve this objective, the first step involved preparing modified pumice catalyst pellets by impregnating them with Pt metal followed by activation at a temperature of 500 °C. The second step involved characterizing the Pt/pumice catalyst, including the surface distribution of Pt metal using SEM. The third step involved conducting the catalyst activity test against 3-methyl-1-butanol in a reactor (furnace) at temperatures ranging from 400 to 500°C with a flow system for the feed. The fourth step involved analyzing the conversion results using GC-MS chromatograms. The research results showed that the Si/Al ratio in the modified Pt/Pumice catalyst using a PtCl4 solution with a concentration of 0.0321 M for impregnation was 4:1, compared to 4.8:1 for Pt/Zeolite and 3.2:1 for Pt/ABP. The modified catalyst activity test for 3-methyl-1-butanol showed the following conversion results: Pt/Pumice 27.63%, Pt/Zeolite 23.85%, Pt/Black Pumice 14.81%, and for platinum catalyst, the conversion was 22.35%. These results indicated that the highest conversion was observed in the treated sample A-3 under the reaction condition of 450°C. The conversion products analyzed using GC-MS showed the presence of three molecules: 3-methylbutanal, 2-methylbutanal, and anhydrous isobutanoate.

Biomass Demineralization and Pretreatment Strategies to Reduce Inhibitor Concentrations in Itaconic Acid Fermentation by Aspergillus terreus

Itaconic acid (IA) is a platform chemical, derived from non-petroleum sources, produced through the fermentation of glucose by Aspergillus terreus. However, producing IA from alternative sugar sources (e.g., lignocellulose) has been shown to be problematic, requiring post-hydrolysis mitigation to allow growth and IA production by the fungus. It is well known that the side products of lignocellulosic biomass conversion to sugars act as microbial growth inhibitors. An uncommon feature of fungal organic acid fermentations is production inhibition caused by mineral ions in biomass hydrolysate after pretreatment and enzymatic hydrolysis. To minimize mineral introduction during pretreatment and hydrolysis, we determined the sources of growth and production inhibitors at each of these steps. Biomass demineralization and four pretreatment strategies were evaluated for inhibitor introduction. Dilution assays determined the approximate degree of inhibition for each hydrolysate. An ammonium hydroxide pretreatment of demineralized wheat straw presented the lowest concentration of inhibitors and concomitant lowest inhibition: subsequent fermentations produced 35 g L−1 IA from wheat straw hydrolysate (91 g L−1 sugar) without post-hydrolysis mitigation.

Niobium Pentoxide as an Acid Catalyst: An Overview

The global chemical industry is under increasing pressure to adopt more sustainable practices, as most chemical products exceed environmental safety limits. Given that chemical production largely relies on catalytic processes, the development of solid acid catalysts has become crucial for more sustainable production. Among these catalysts, niobium pentoxide stands out due to its strong acid sites, which remain active in the presence of water, and its stability under hydrothermal conditions. Recent studies have demonstrated that these solids maintain their catalytic activity even in the presence of strong bases, making them unique catalysts. This review explores the potential of niobium pentoxide as an acid catalyst, addressing advances in synthesis techniques, surface modifications, and combinations with other materials to enhance its catalytic performance in sustainable applications, such as biomass conversion and biofuel production, opening new pathways for the production of greener chemicals. Finally, the future perspectives of niobium pentoxide - based catalysts in green chemistry are discussed.

Enhancing methane production from distillers’ grains by cattle manure in solid-state anaerobic digestion: Focusing on biodegradability, acidification and indigenous microorganisms

Distillers’ grains has high potential in methane production but the process is affected by the acidification in anaerobic digestion. To enhance the methane production in solid-state anaerobic digestion, distillers’ grains was co-digested with cattle manure in different proportions in this study. Compared to distillers’ grains, cattle manure performed lower biodegradability but higher alkalinity and nutrients, hence relieved acidification and drove microbial succession for methane enhancement in the co-digestion with distillers’ grains. The highest increase in total methane yield (10.67 %) was observed in the co-digestion of distillers’ grains and cattle manure at the proportion of 70:30 (T3). This was the synergistic action of reduced acidification, relatively high biodegradability of feedstocks, and balanced composition of hydrolytic bacteria, syntrophic bacteria and acetoclastic methanogens. Further analysis revealed the positive effects of indigenous microorganisms derived from distillers’ grains and cattle manure in methane enhancement. The enrichment of Sedimentibacter, Desulfitibacter, Tepidanaerobacter from distiller's grains, and Eubacterium, Methanoculleus, Methanobacterium, Methanobrevibacter mainly from cattle manure synergistically promoted organics conversion and methane production in T3. This study further affirmed the potential use of distillers’ grains in solid-state anaerobic digestion and provided a favorable strategy for its better methane production.

Research on reaction mechanisms on chemical looping gasification of naphthalene over NiFe2O4 for syngas production: An experimental and theoretical study

The effective removal of tar during biomass gasification is a significant challenge that can be addressed by chemical looping gasification (CLG), which offers a promising alternative for converting biomass into syngas with reduced tar generation. In this study, we investigated the mechanism of CLG of naphthalene as a model biomass tar compound over NiFe2O4 to produce syngas. Both experimental and simulation results indicate the optimal operating conditions for syngas production are 1000℃ and an O/C ratio of 1:1. Under the optimal reaction conditions, the experimental and simulated CO yields were 67 vol% and 73 vol%, respectively, while H2 yields were 22 vol% and 24 vol%. Additionally, carbon conversion rates reached 78% and 76%. Thermodynamic calculations and molecular dynamics simulations revealed that the reactions proceed spontaneously, with increasing temperature favoring naphthalene conversion and syngas production. Density functional theory results indicate that the reaction pathway centered on the carbon at the α-position is the key to naphthalene and NiFe2O4 conversion. The optimal reaction pathways for H2 and CO formation were explored. This study on the CLG of naphthalene over NiFe2O4 provides a theoretical basis for the development of more efficient CLG processes with reduced tar formation.

Tailoring Interlayer Microenvironment of 2D Layered Double Hydroxides for CO2 Reduction with Enhanced C2+ Production.

Both the physicochemical properties of catalytic material and the structure of loaded catalyst layer (CL) on gas diffusion electrode (GDE) are of crucial importance in determining the conversion efficiency and product selectivity of carbon dioxide reduction reaction (CO2RR). However, the highly reducing reaction condition of CO2RR will lead to the uncontrollable structural and compositional changes of catalysts, making it difficult to tailor surface properties and microstructure of the real active species for favored products. Herein, the interlayer microenvironment of copper-based layered double hydroxides (LDHs) is rationally tuned by a facile ink solvent engineering, which affects both the surface characters and microstructure of CL on GDE, leading to distinct catalytic activity and product selectivity. According to series of in situ and ex situ techniques, the appropriate surface wettability and thickness of porous CL are found to play critical roles in controlling the local CO2 concentration and water dissociation steps that are key for hydrogenation during CO2RR, leading to a high Faradaic efficiency of 75.3% for C2+ products and a partial current density of 275mAcm-2 at -0.8V versus RHE. This work provides insights into rational design of efficient electrocatalysts toward CO2RR for multi-carbon generation.

Triple enzymatic cascade reaction to produce hydroxytyrosol acetate from olive leaves using integrated membrane bioreactors.

An integrated system of three membrane bioreactors (MBRs) has been developed that cascades three different enzymatic reactions. The integrated system was applied to produce hydroxytyrosol acetate from oleuropein extracted from olive leaves. Different reactor configurations for each reaction were tested and individually optimized to select the MBR to ensure high conversion and continuous production of oleuropein aglycone (OA), hydroxytyrosol (HY) and hydroxytyrosol acetate (HA). Based on this study, the most performing configuration of the integrated system was identified. In the first reaction, oleuropein was converted to OA using a biocatalytic membrane reactor (BMR) with immobilized β-glucosidase in polymeric membranes (conversion 98%). The OA was then fed to another BMR, where it was converted to HY (conversion: 70%) by an immobilized mutant of the promiscuous hydrolase/acyltransferase (PestE) (from the thermophilic archaeon Pyrobaculum calidifontis VA1). The HY produced was then acetylated using PestE immobilized on magnetic nanoparticles in a multiphase MBR (conversion: 98%) and simultaneously extracted (extraction: 98%) in ethyl acetate. The work demonstrates that continuous cascade enzymatic reactions can be engineered using artificial membranes to tailor enzyme compartmentalization, mass transport and phase contact according to reaction requirements. Besides, environmental factors proved the sustainability of the integrated membrane bioreactive system.

Green Diesel Production Through Deoxygenation Reaction with Natural Zeolite-supported Nickel and Copper Catalyst

The depletion of fossil fuels and their environmental impact necessitate sustainable alternatives. Green diesel, a biofuel with a chemical structure similar to conventional diesel, has gained traction as a viable alternative. This study explores the development of a cost-effective catalyst for green diesel production using deoxygenation. Deoxygenation refers to a broad class of chemical reactions where oxygen atoms are stripped from a molecule. This research employed abundant Indonesian natural zeolite (NZ) as a catalyst support, impregnated with non-noble metals, nickel (Ni), and copper (Cu). The investigation revealed that the NiCu/NZ catalyst achieved the highest oleic acid conversion (90.40%) and green diesel yield. The product distribution, ranging from C15 to C18 hydrocarbons, reflects the moderate acidity of the catalyst, promoting diverse cracking patterns compared to highly acidic catalysts. Additionally, the high specific surface area of NZ facilitates the conversion and good product distribution. Furthermore, the optimization process demonstrated that increasing hydrogen pressure during deoxygenation enhances both conversion rate and green diesel production.

Efficient photoreforming of plastic waste using a high-entropy oxide catalyst

Simultaneous catalytic hydrogen (H2) production and plastic waste degradation under light, known as photoreforming, is a novel approach to green fuel production and efficient waste management. Here, we use a high-entropy oxide (HEO), a new family of catalysts with five or more principal cations in their structure, for plastic degradation and H2 production. The HEO shows higher activity than that of P25 TiO2, a benchmark photocatalyst, for the degradation of polyethylene terephthalate (PET) plastics in water. Several valuable products are produced by photoreforming of PET bottles and microplastics including H2, terephthalate, ethylene glycol and formic acid. The high activity is attributed to the diverse existence of several cations in the HEO lattice, lattice defects, and appropriate charge carrier lifetime. These findings suggest that HEOs possess high potential as new catalysts for concurrent plastic waste conversion and clean H2 production.

Mitigating the negative impact of over-association for conversational query production

Conversational query generation aims at producing search queries from dialogue histories, which are then used to retrieve relevant knowledge from a search engine to help knowledge-based dialogue systems. Trained to maximize the likelihood of gold queries, previous models suffer from the data hunger issue, and they tend to both drop important concepts from dialogue histories and generate irrelevant concepts at inference time. We attribute these issues to the over-association phenomenon where a large number of gold queries are indirectly related to the dialogue topics, because annotators may unconsciously perform reasoning with their background knowledge when generating these gold queries. We carefully analyze the negative effects of this phenomenon on pretrained Seq2seq query producers and then propose effective instance-level weighting strategies for training to mitigate these issues from multiple perspectives. Experiments on two benchmarks, Wizard-of-Internet and DuSinc, show that our strategies effectively alleviate the negative effects and lead to significant performance gains (2%∼5% across automatic metrics and human evaluation). Further analysis shows that our model selects better concepts from dialogue histories and is 10 times more data efficient than the baseline.

Cerium(III)-induced structural transformation of hexagonal birnessite: Effect of mineral phase transition on arsenite transport and valence changes

The widespread mining and application of rare earth elements (REEs) have led to their continuous accumulation in the environment, with increasing concentrations in soil. The interaction between the most abundant REEs, cerium (Ce), and the prevalent hexagonal birnessite (HB) in the environment is worth attention. HB is one of the most effective metal oxides for the oxidation of arsenite [As(III)] and subsequent adsorption, and thus for arsenic (As) immobilization. Therefore, in this study, we investigated the effect of the presence of Ce(III) ion on the HB formation process and the influence of generating minerals on the oxidation and removal of As(III). Research has found that the interfacial reactions of REEs in manganese (Mn) minerals not only affect their cycling but also alter the properties of the Mn minerals, thereby affecting the environmental fate of As. The results indicated that the presence of Ce ions affected the structure of HB during mineral synthesis and reduced the crystallinity of the conversion products. Their substitution for Mn(IV) in the lattice increased the specific surface area of minerals, reduced particle size, and produced more hydroxyl groups that were conducive to the immobilization of As(III). Meanwhile, Ce(III) was oxidized to Ce(IV) during the formation of Ce-bearing hexagonal birnessite (Ce-HB), and CeO2 nanoparticles were formed on the mineral surface and the removal rate of As(III) by Ce-HB was greatly improved. When the As concentration was lower than 6 mg·L−1, the removal effect of Ce-HB could reach the drinking water standard. However, the oxidation rate decreased due to the decrease in the proportion of Mn(IV). This study fundamentally reveals the behavior of HB coexisting with Ce in the migration and transformation of As(III) in the environment.

An alternative to petrochemicals: biomass electrovalorization.

Replacing petrochemicals with refined waste biomass as a sustainable chemical source has become an attractive option to lower global carbon emissions. Popular methods of refining lignocellulosic waste biomass use thermochemical processes, which have significant environmental downsides. Using electrochemistry instead would overcome many of these downsides, directly driving chemical reactions with renewable electricity and revolutionizing the way many chemicals are produced today. This review mainly focuses on two furanic platform chemicals that are produced from the dehydration of cellulose, 5-hydroxymethylfurfural and furfural, which can be electrochemically reduced or oxidized to replace fuels and monomers that today are obtained from petrochemicals. Critical parameters such as electrode materials and electrolyte pH are discussed in relation to their influence on conversion efficiency and product distribution.This article is part of the discussion meeting issue 'Green carbon for the chemical industry of the future'.

Investigations of thermal effects during pyrolysis of agro-forestry biomass and physicochemical characterizations of biofuel products

The development of biofuels from waste residues is critical due to higher emissions of greenhouse gases from petroleum and coal and rising energy demand. Converting agricultural and forestry biomass into biofuel products efficiently is a practical approach for simultaneously addressing renewable energy security and waste management challenges. This study examines the physicochemical characteristics of several agro-forestry residues such as camelina meal, mustard meal, flax straw, hemp straw and spruce wood to assess their suitability as feedstocks for pyrolysis to generate biochar, bio-oil and gases. An analysis was conducted to evaluate the influence of temperature (300–525 °C), heating rate (5–35 °C/min) and reaction time (30–75 min) to assess their impact on conversion efficiency and product distribution during pyrolysis. The optimal temperature, heating rate and reaction time for pyrolysis of camelina meal as a model biomass were determined to be 450 °C, 5 °C/min and 30 min, respectively. Physicochemical characteristics of biochar and bio-oil were analyzed to determine the impact of controlled thermal breakdown through slow pyrolysis. As the temperature increased, the calorific value, carbon content and thermal stability of biochar increased due to the removal of volatile matter and the development of aromatic carbon and phenolic features.

Effect of Cu doping on morphology and properties of calcium ferrite and its application as oxygen carrier in chemical looping hydrogen production

Chemical looping hydrogen production with inherent CO2 capture has been widely recognized as a clean and efficient approach to high-purity hydrogen production because of the ultra-pure H2 product without any purification facilities. It is crucial to develop oxygen carriers with better performance to improve fuel conversion and hydrogen production efficiency. The potential of Ca2Fe2O5 in steam converting has been confirmed. However, its lower oxygen transfer capacity, that is, it tends to produce lower fuel conversion in fuel reactors, which will limit its practical application. Here, we report the development of Cu-doped Ca2Fe2O5-based oxygen carriers using sol-gel technology. The effects of B-site substitution of Cu element on the morphological properties and redox properties of Ca2Fe2-xCuxO5 (x = 0, 0.1, 0.25, 0.5, 1) oxygen carriers were evaluated based on experiments and density functional theory calculations. The results show that Cu doping not only elevated the surface oxygen content and enhanced the oxygen activity of the oxygen carriers, but also increased the Fe3+ at the B-site, thus enhanced their binding ability with oxygen molecules. Vacancy formation was a rate-determining step in the chemical looping hydrogen production (CLH), and Cu-doped Ca2Fe2O5 reduced the energy of oxygen vacancy formation. In the CLH process, the doping of Cu significantly improved the hydrogen productivity and fuel conversion rate. The fuel conversion rate was positively correlated with the doping amount of Cu. When x = 1, Ca2Fe2-xCuxO5 had the maximum fuel conversion rate, and its average conversion was 54.2% more than that of undoped Ca2Fe2O5. Ca2Fe2-xCuxO5 with x = 0.25 was the most suitable for CLH with the highest H2 yield, which was 20.3% more than that of Ca2Fe2O5. Moreover, its properties remained stable over multiple redox cycles with high activity and stability for CO-CLH.

Synthesis, Structure, and Properties of 1,3‐Diaryl‐7‐imino‐1,7‐dihydrobenzo[e][1,2,4]triazines: Products of Unexpected Conversion of Polyfluorinated Blatter Radicals

AbstractDerivatives of the first substituted 7‐imino‐1,7‐dihydrobenzo[e][1,2,4]triazines, namely 1‐(2,3,5,6‐tetrafluoropyridin‐4‐yl)‐N,3‐diphenyl‐7‐(phenylimino)‐1,7‐dihydrobenzo[e][1,2,4]triazin‐6‐amine and 1‐(pentafluorophenyl)‐N‐phenyl‐7‐(phenylimino)‐3‐(2,3,4,5‐tetrafluorophenyl)‐1,7‐dihydrobenzo[e][1,2,4]triazin‐6‐amine, were unexpectedly isolated as the only products in yields of about 20–30 % after an attempt to obtain Blatter radicals from the corresponding amidrazones bearing polyfluorinated electron‐withdrawing substituents. All new compounds were fully characterized, and their molecular and crystal structure was determined by single‐crystal X‐ray diffraction.

Mutual Transformations of Polysulfide Chromophore Species in Sodalite-Group Minerals: A DFT Study on S6 Decomposition.

It is known that various polysulfide species determine the color of sodalite-group minerals (haüyne, lazurite, and slyudyankaite), and that heating induces their transformations and color change, but the mechanisms of the transitions are unknown. A prominent example is the decay of cyclic S6 molecule. Using density-functional simulations, we explore its main decay pathways into the most probable final reaction products (the pairs of radical anions S3⋅-+S3⋅- and S2⋅-+S4⋅-). It was found that the most favorable reaction path involves initial capture of one electron by the S6 molecule, which greatly facilitates its decay of S6 and leads to the opening of the S6 cycle, and subsequent decomposition of the thus formed chain radical anion, with a limiting energy barrier of ~0.4 eV. Neutral polysulfide molecules capture one electron with a significant energy reduction. The radical anions Sn⋅- (n=2-6) are the most stable ones among corresponding species with the same n values and different charges. The capture of the second electron by S6⋅- occurs with a huge energy barrier (~2 eV). The results of the DFT calculations are in agreement with experimental data on the products of thermal conversions of extra-framework S-bearing groups in sodalite-group minerals.

Numerical simulation of gasifier optimization for combined hydrogen production and carbon reduction in a chemical looping gasification (CLG) system

Chemical looping gasification (CLG) for combined hydrogen production and carbon capture represents a significant pathway for the clean, low-carbon utilization of traditional fossil fuels. Currently, a significant knowledge gap remains concerning the interplay between reactor configuration optimization and the complex gas–solid interactions in the CLG systems. This study integrates reactive computational fluid dynamics-discrete element method (CFD-DEM) simulations with a coarse-grained model (CGM) to analyze 3D coal-based CLG systems. The spatiotemporal distributions of gas–solid flow dynamics and thermochemical characteristics are revealed. It is found that increasing the gasifier height enhances fuel conversion and hydrogen production but compromises CO2 absorption. Smaller reactor diameters induce excessively rapid gas–solid flows, leading to incomplete fuel conversion and reduced hydrogen yield, while larger diameters cause uneven flows, significantly deteriorating hydrogen production and carbon absorption efficiency. Based on the simulation findings, the optimal height-to-diameter ratio for the gasifier in a CLG system is approximately 28.8, optimizing H2 production while maintaining efficient CO2 absorption. Moreover, the superficial gas velocity has a multifaceted influence on the hydrogen production and carbon reduction performance in the CLG process, necessitating a comprehensive consideration of its effects on fuel reaction time, gas–solid interactions, and other factors.