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The CO2 methanation reaction, or Sabatier reaction, is experiencing renewed interest in the context of large‐scale recycling of point CO2 emissions, leading to the power‐to‐gas technology. The reaction represents a flexible route to transform CO2 into methane by hydrogenation with (green) dihydrogen. This exothermic transformation takes place at a reasonable rate at temperatures above 200 °C and is directed to the targeted product at low temperatures. The CO2 methanation nevertheless remains kinetically limited due to the chemical stability of CO2 and the high bond dissociation energy for C═O in CO2. Therefore, the current urgent demand is for the development of catalysts and associated processes with superior activity for CO2 activation at low temperatures. This critical review aims to overview the state of the art of this low‐temperature technology using thermal, plasma and photo‐assisted catalysis. We summarize research advances around low‐temperature CO2 methanation, focusing on catalyst formulations (metal, supports and promoters), reaction mechanisms and suitable activation processes. We discuss each of these critical aspects of the technology and identify the main challenges and opportunities for low temperature (≤200 °C) CO2 methanation. [ABSTRACT FROM AUTHOR]

Catalytic conversion of carbon dioxide (CO2) into value‐added chemicals is of pivotal importance, well the cost of capturing CO2 from dilute atmosphere is super challenge. One promising strategy is combining the adsorption and transformation at one step, such as applying alkali solution that could selectively reduce carbonate (CO32−) as consequences of CO2 adsorption. Due to complexity of this system, the mechanistic details on controlling the hydrogenation have not been investigated in depth. Herein, Ru/TiO2 catalyst was applied as a probe to elucidate the mechanism of CO32− activation, in which with thermodynamic and kinetic investigations, a compact Langmuir‐Hinshelwood reaction model was established which suggests that the overall rate of CO32− hydrogenation was controlled by a specific C−O bond rupture elementary step within HCOO− and the Ru surface was mainly covered by CO32− or HCOO− at independent conditions. This assumption was further supported by negligible kinetic isotope effects (kH/kD≈1), similarity on reaction barriers of CO32− and HCOO− hydrogenation (ΔH≠hydr,Na2CO3 and ΔH≠hydr,HCOONa) and a non‐variation of entropy (ΔS≠hydr≈0). More interestingly, the alkalinity of the solution is certainly like a two sides in a sword and could facilitate the adsorption of CO2 while hold back catalysis during CO32− hydrogenation. [ABSTRACT FROM AUTHOR]

High‐entropy oxides (HEOs) are an emerging class of materials whose compositional complexity has garnered attention because of their tailorable chemistries and unique properties arising from extreme configurational entropy. Solid‐state methods are often employed to synthesize HEOs, but such methods result in poor material properties for catalytic processes, leaving HEOs less studied for catalysis. Here we utilize different wet‐synthesis strategies to produce porous HEOs and investigate their performance in heterogeneous CO2 hydrogenation to methane. Specifically, HEOs were synthesized using hydrothermal, co‐precipitation, and solvothermal methods, resulting in different morphologies like platelets or spheres. Of the tested materials, HEOs with 2‐D platelets derived from hydrothermally‐synthesized high‐entropy layered double hydroxides had superior catalytic performance, especially in low‐temperature regimes (<300 °C). K‐edge XANES indicated that metallic sites (Ni0‐Co0) were formed during the reaction, and these metallic sites are dispersed into the HEO matrix which is confirmed by STEM/elemental mapping. This facile synthesis approach allows for realized synergy between the metallic sites and the HEO support, leading to superior performance for CO2 methanation compared to low‐entropy counterparts. Finally, this study illustrates how HEOs offer new avenues of tailorability in terms of the interplay between support, active site and reaction temperatures for heterogeneous catalysis. [ABSTRACT FROM AUTHOR]

Poly(heptazine imide) (PHI), one of the crystalline or long‐range ordered allotropes of polymeric carbon nitride, is a promising polymeric photocatalyst; however, preparation of highly crystalline PHI remains a challenge. Herein, through a bottom‐up strategy involving repair of structural defects and increase of specific surface area of melon precursor, we prepared PHI nanorods with dramatically improved long‐range order. The resulting PHI exhibited a shift of product selectivity in CO2 photoreduction from CO to CH4 with a high methanation activity in contrast to the pristine PHI with relatively low long‐range order. The improvement of long‐range order for PHI remarkably enhanced the separation efficiency and transfer kinetics of photogenerated charges as well as the adsorption for *CO intermediate. This study revealed the relationship between the precursor structure and PHI crystal growth in ionothermal synthesis, and also showcased the great potential of highly crystalline PHI in artificial photosynthesis. [ABSTRACT FROM AUTHOR]

Power‐to‐methane (PtM) offers an efficient opportunity for surplus renewable energy storage, but heat management is a major challenge for conducting the highly exothermic methanation reaction. To address this challenge, this study presents the first successful demonstration of core‐shell catalyst pellets in a pilot‐scale reactor for CO2 methanation. Experiments in a wall‐cooled fixed‐bed reactor are conducted with diluted and undiluted reactant feed under systematic variation of cooling temperature and inlet gas flow rate. The results show that core‐shell catalyst pellets significantly reduce the hot‐spot temperature while maintaining comparable reactant conversions to uncoated catalyst pellets at the same conditions. Additionally, core‐shell catalyst pellets allow for undiluted reactant feed at comparably low hot‐spot temperatures (approx. 600 °C). [ABSTRACT FROM AUTHOR]

The understanding of deactivation processes in heterogeneous catalysis is key for the development of new materials and exploration of new operation windows. In this contribution, the periodic transient kinetic method (PTK) is used to identify and separate catalyst deactivation processes for the first time. The PTK method is applied for a standard Ni/Al2O3 catalyst in CO and CO2 methanation for 24 h and compared to steady‐state experiments. For the example reactions, the study exhibits different deactivation behavior for CO and CO2 methanation. The results demonstrate that the PTK method delivers an insight into the deactivation process and furthermore gives evidence for the underlying mechanism. [ABSTRACT FROM AUTHOR]

The synergies from integrating direct air capture and CO2 methanation are assessed and quantified. Three direct air capture and methanation processes with different integration strategies are proposed: only heat integration, direct air capture sorbent regeneration with high‐pressure H2, and complete integration in a single unit. The heat integration study via pinch analysis evaluated the potential energy demand reduction. Overall autothermal operation is achievable, as the heat generated in methanation often exceeds that required for direct air capture sorbent regeneration. A novel process combining CO2 adsorption and methanation in one reactor provided the best productivity and energy demand results. However, this design requires complex cycles and strict demands on the sorbent and catalyst, requiring further development and experimental demonstration. [ABSTRACT FROM AUTHOR]

The effects of H2O in heterogeneous catalysis of COx (CO2, CO) hydrogenation have been intricate and controversial for many years. On the one hand, H2O molecules and their derivatives (O, H, OH) serve as reactants or co‐reactants, playing a role in modulating the reaction pathway through specific mechanisms. On the other hand, the presence of H2O can influence the catalytic performance by altering the physicochemical properties of the catalyst, such as particle size and chemical state, among others. More importantly, the dual role of H2O leads to both positive and negative outcomes, challenging our understanding of its impact. In this mini review, the relevant research results are summarized in terms of the promoting and inhibiting effects of H2O of the COx hydrogenation reaction (e. g., synthesis of methanol, Fischer‐Tropsch synthesis, methanation, etc.) and discussed from the perspective of catalyst and reaction mechanism, which may provide a certain theoretical basis for the design and development of high‐performance catalysts and referable experience for the further exploration and utilization of H2O effects on related fields as well. [ABSTRACT FROM AUTHOR]

CO2 reduction by sunlight under mild reaction conditions is a research area of increasing interest expected to favor decarbonization and produce fuels and chemicals in the circular economy. We hereby report on the development of a series of titanium oxide‐based solids produced by calcination of MIL‐125(Ti)‐NH2 decorated with RuOx nanoparticles (1 wt %) material at temperatures from 350 to 650 °C and used as photocatalysts for CO2 methanation under simulated sunlight irradiation (45 mW/cm2) at <200 °C and 1.5 atm total pressure. The material synthesized at 350 °C produced the highest photoactivity of the series (4.73 mmol g−1 CH4 at 22 h and an apparent quantum yield at 400, 500 and 750 nm of 0.76, 0.65 and 0.54 %, respectively), comparing favorably with the activities of other MOF‐based materials reported so far. Insights into the material's photocatalytic performance and a study of the possible reaction pathways during CO2 methanation were obtained by electrochemical impedance, electron spin resonance, photoluminescence and in situ FT‐IR spectroscopies together with transient photocurrent and hydrogen temperature programed desorption measurements. The study showed the possibility of using MOF‐based materials as precursors to develop metal oxide photocatalysts with enhanced activities for solar‐driven gaseous CO2 photomethanation. [ABSTRACT FROM AUTHOR]

Thermocatalytic conversions of carbon dioxide (CO2) to value‐added products offer promising approaches to achieving net negative emissions. The catalysts for CO2 conversions, particularly for CO2 hydrogenation reactions, usually involve more than one catalytic sites working together. In this review, we first introduce the advanced characterization techniques used to identify the catalytic sites in CO2 hydrogenation catalysts, sites for hydrogen (H2) activation and CO2 adsorption/activation. We then discuss how the dual or multiple‐site configurations influence the catalytic activity and selectivity in reactions such as reverse water‐gas shift (RWGS), CO2 methanation, and CO2 hydrogenation for methanol (MeOH). We finally explain the Catalytic Sites Contiguity (CSC) concept that our research group developed from the work in CO2 reforming of methane and use it to understand the relationship between the spatial arrangement of catalytic sites and the efficiency of reactant activation and conversion in recent publications on MeOH synthesis from CO2 hydrogenation. We hope our insights into the impact of CSC on catalytic performance lead to a potential top‐down design method in optimizing the CO2 hydrogenation catalysts. [ABSTRACT FROM AUTHOR]

Utilizing near zero‐carbon NH3 as fuel in engines is promising for carbon‐neutrality. However, the application of NH3 into the engine suffers from the intrinsic poor combustion characteristics of NH3 and the emission of harmful NOx exhausts. Herein, we proposed and successfully confirmed a novel scenario for converting a conventional “CH4‐fueled” engine to “NH3‐fueled” engine. Specifically, CH4 was used to power the internal combustion engine and release CO2 as the exhaust. Afterwards, we put forward two routes to convert the exhaust and NH3 into N2 and CH4 for enclosing the carbon cycle. The first “spatially decoupled” route splits the exhaust treatment into NH3 cracking over Ru clusters on the calcined Mg−Al hydrotalcite (Ru/MAO) and CO2 methanation over a commercial Ni/Al2O3. Both NH3 and CO2 were almost completely converted into the target products under their respective optimal conditions. The second “spatially coupled” route refers to an one‐pot reaction of NH3 and CO2 into N2, CH4, and H2O. Due to the mismatch of reaction conditions and the competitive adsorption of reactants, the conversions of NH3 and CO2 were lowered to 80.1 % and 49.3 %, respectively, over Ru/MAO under 1 bar (CO2:NH3=3 : 8) at 550 °C. [ABSTRACT FROM AUTHOR]

Developing solid‐solution nano‐alloys from immiscible metals has garnered significant interest; however, the high formation entropy poses substantial challenges in synthesis, hindering a comprehensive understanding of the catalytic mechanisms under alloying effects. Herein, the synthesis of small‐sized (≈2.5 nm) RuxNi1‐x solid‐solution alloy nanoparticles with precisely controlled Ru/Ni ratios across a broad compositional range is reported for the first time, despite their bulk immiscibility. The Ru0.76Ni0.24/TiO2 catalyst, with an optimized Ru/Ni ratio, delivers superior photo‐thermal catalytic activity for CO2 methanation, achieving a CH4 production rate of 3.58 mol gmetal−1 h−1 with 94% selectivity at 250 °C under light irradiation, representing a 2.82‐fold enhancement over monometallic Ru/TiO2. Comprehensive investigations reveal that the reconstruction of electronic structure at Ru–Ni active sites enhances the adsorption/activation of reactants, promotes the transformation of intermediate HCO3* to HCOO*, and facilitates the separation of the photo‐generated charge carriers witnessed by the femtosecond time‐resolved transient absorption (fs‐TA) spectroscopy. These combined effects collectively result in significantly enhanced CH4 formation performance. This work highlights the potential of regulating catalytic sites in immiscible metal combinations for photo‐thermal catalytic CO2 conversion, underscoring the promise of these cost‐effective alloys in heterogeneous catalysis. [ABSTRACT FROM AUTHOR]

Solar light‐driven conversion of CO2 into chemicals with high calorific value is regarded as an upcoming carbon utilization technology for alleviating the energy crisis. This technique faces the challenge of low CO2 conversion and product yield due to charge recombination in the catalyst. In this paper, a dual‐reaction site heterojunction catalyst was designed and fabricated by combining NiO with Bi3O4Br nanosheets, for the separation of CO2 reduction and H2O oxidation semireactions, which effectively promoted electrons and holes separation. The resulting catalyst exhibited a high CH4 production rate (8.12 µmol/g) and selectivity (94.69%). Electron distribution and band structure were investigated to explain the satisfactory catalytic performance. In addition, combining the in‐situ DRIFTS results, a formic acid‐intermediated CO2‐to‐CH4 reaction pathway was proposed. This work aims to pave the way for CH4 production via CO2 photoreduction with high efficiency and selectivity. [ABSTRACT FROM AUTHOR]

In photocatalysis, the resulted heat by the relaxation of most of incident light no longer acts as the industrially favorite driving force back to the target photo‐reaction due to more or less the negative relation between photocatalytic efficiency and temperature. Here, we reported a visible light‐sensitized protocol that completely reversed the negatively temperature‐dependent efficiency in photo‐driven CO2 methanation with saturated water vapor. Uniform Pt/N‐TiO2/PDI self‐assembly material decisively injects the excited electron of PDI sensitizer into N‐TiO2 forming Ti−H hydride which is crucially temperature‐dependent nucleophilic species to dominate CO2 methanation, rather than conventionally separated and trapped electrons on the conductor band. Meanwhile, the ternary composite lifts itself temperature from room temperature to 305.2 °C within 400 s only by the failure excitation upon simulated sunlight of 2.5 W/cm2, and smoothly achieves CO2 methanation with a record number of 4.98 mmol g−1 h−1 rate, compared to less than 0.02 mol g−1 h−1 at classic Pt/N‐TiO2/UV photocatalysis without PDI sensitization. This approach can reuse ~53.9 % of the relaxed heat energy from the incident light thereby allow high‐intensity incident light as strong as possible within a flowing photo‐reactor, opening the most likely gateways to industrialization. [ABSTRACT FROM AUTHOR]

The conversion of CO2‐H2 mixtures on Ni‐based catalysts can proceed through either the reverse water gas shift reaction (RWGS) path to produce CO or the CO2 methanation path to produce CH4. The balance between these competing reactions depends on both the reaction conditions and catalyst structure. In this study, using surface‐sensitive infrared and ambient pressure X‐ray photoelectron spectroscopies, we investigate the effect of reaction conditions on the interaction between CO2 and H2 on a Ni(111) model catalyst. Our findings highlight the occurrence of RWGS, involving direct dissociation of CO2 to CO and atomic oxygen, followed by oxygen reacting with hydrogen to form H2O, and CO and H2O desorption. Hydrogen affects the distribution of CO between hollow and top sites by displacing oxygen from the energetically preferred hollow sites. The overall balance between oxygen production from CO2 dissociation and oxygen removal by hydrogen governs the oxygen coverage and consequently the distribution of CO between top and hollow sites. This balance is significantly influenced by the reaction temperature and the H2/CO2 partial pressures. [ABSTRACT FROM AUTHOR]

Biogas offers significant benefits as a renewable energy source, contributing to decarbonization, waste management, and economic development. This comprehensive review examines the historical, technological, economic, and global aspects of biomethane production, focusing on the key players such as China, the European Union, and North America, and associated opportunities and challenges as well as future prospects from an Australia perspective. The review begins with an introduction to biogas, detailing its composition, feedstock sources, historical development, and anaerobic digestion (AD) process. Subsequently, it delves into major biomethane production technologies, including physicochemical absorption, high‐pressure water scrubbing (HPWS), amine scrubbing (AS), pressure swing adsorption (PSA), membrane permeation/separation (MP), and other technologies including organic solvent scrubbing and cryogenic separation. The study also discusses general guidelines of techno‐economic assessments (TEAs) regarding biomethane production, outlining the methodologies, inventory analysis, environmental life cycle assessment (LCA), and estimated production costs. Challenges and opportunities of biogas utilization in Australia are explored, highlighting and referencing global projections, polarization in production approaches, circularity in waste management, and specific considerations for Australia. The review concludes discussing future perspectives for biomethane, emphasizing the importance of technological advancements, policy support, and investment in realizing its full potential for sustainable energy and waste management solutions. [ABSTRACT FROM AUTHOR]

It has been known that plastics with undegradability and long half‐times have caused serious environmental and ecological issues. Considering the devastating effects, the development of efficient plastic upcycling technologies with low energy consumption is absolutely imperative. Catalytic hydrogenolysis of single‐use polyethylene over Ru‐based catalysts to produce high‐quality liquid fuel has been one of the current top priority strategies, but it is restricted by some tough challenges, such as the tendency towards methanation resulting from terminal C−C cleavage. Herein, we introduced Ru nanoparticles supported on hollow ZSM‐5 zeolite (Ru/H‐ZSM‐5) for hydrocracking of high‐density polyethylene (HDPE) under mild reaction conditions. The implication of experimental results is that the 1Ru/H‐ZSM‐5 (~1 wt % Ru) acted as an effective and reusable bifunctional catalyst providing higher conversion rate (82.53 %) and liquid fuel (C5−C21) yield (62.87 %). Detailed characterization demonstrated that the optimal performance in hydrocracking of PE could be attributed to the moderate acidity and appropriate positively charged Ru species resulting from the metal‐zeolite interaction. This work proposes a promising catalyst for plastic upcycling and reveals its structure‐performance relationship, which has guiding significance for catalyst design to improve the yield of high‐value liquid fuels. [ABSTRACT FROM AUTHOR]

Photothermal CO2 methanation reaction represents a promising strategy for addressing CO2‐related environmental issues. The presence of efficient tandem catalytic sites with a localized high‐temperature is an effective pathway to enhance the performance of CO2 methanation. Here the bimetallic RuCo nanoparticles anchored on ZrO2 fiber cotton (RuCo/ZrO2) as a photothermal catalyst for CO2 methanation are prepared. A significant photothermal CO2 methanation performance with optimal CH4 selectivity (99%) and rate (169.93 mmol gcat−1 h−1) is achieved. The photothermal energy of the RuCo bimetallic nanoparticles, confined by the infrared insulation and low thermal conductivity of the ZrO2 fiber cotton (ZrO2 FC), provides a localized high‐temperature. In situ spectroscopic experiments on RuCo/ZrO2, Ru/ZrO2, and Co/ZrO2 indicate that the construction of tandem catalytic sites, where the Co site favors CO2 conversion to CO while incorporating Ru enhances CO* adsorption for subsequent hydrogenation, results in a higher selectivity toward CH4. This work opens a new insight into designing tandem catalysts with a photothermal confinement effect in CO2 methanation reaction. [ABSTRACT FROM AUTHOR]

Exsolution of metal nanoparticles (NPs) on perovskite oxides has been demonstrated as a reliable strategy for producing catalyst‐support systems. Conventional exsolution requires high temperatures for long periods of time, limiting the selection of support materials. Plasma direct exsolution is reported at room temperature and atmospheric pressure of Ni NPs from a model A‐site deficient perovskite oxide (La0.43Ca0.37Ni0.06Ti0.94O2.955). Plasma exsolution is carried out within minutes (up to 15 min) using a dielectric barrier discharge configuration both with He‐only gas as well as with He/H2 gas mixtures, yielding small NPs (<30 nm diameter). To prove the practical utility of exsolved NPs, various experiments aimed at assessing their catalytic performance for methanation from synthesis gas, CO, and CH4 oxidation are carried out. Low‐temperature and atmospheric pressure plasma exsolution are successfully demonstrated and suggest that this approach could contribute to the practical deployment of exsolution‐based stable catalyst systems. [ABSTRACT FROM AUTHOR]

Interparticle hydrogen spillover is the phenomenon of H migration over different catalyst particles, which should be a physical mixture of at least two solid catalysts. In this review, we analyze examples of enhanced catalysis based on interparticle (reverse) hydrogen spillover. Simple physical mixtures of powdered catalysts containing metal catalysts of H2 dissociation/recombination and solid catalysts with active sites for substrate activation significantly enhance catalytic reactions. These reactions include aromatic hydrogenation, CO2 methanation, and the deoxydehydration of polyols, aromatization of lower paraffins, and direct coupling of benzene and alkanes. The acceleration effect and proposed reaction pathway of each example involving interparticle (reverse) hydrogen spillover are summarized. Simple reaction systems comprising physical mixtures of at least two powdery solid catalysts should enable unique catalysis in the future with the aid of interparticle (reverse) hydrogen spillover. [ABSTRACT FROM AUTHOR]

This study investigated the catalytic CO2 methanation using nickel oxide (NiO) nanoparticles and nickel oxalate (NiC2O4) as catalysts. The NiC2O4 precursor was synthesized through a chemical precipitation reaction between nickel (II) nitrate hexahydrate (Ni(NO3)2.6H2O) and oxalic acid (H2C2O4.2H2O). Nickel oxide (NiO) nanoparticles were synthesized through thermal decomposition of NiC2O4 precursor at 450 °C in air. The samples were characterized by XRD, FTIR, BET, SEM, and EDX. The XRD and FTIR analyses revealed that the NiO nanoparticles were well‐crystallized having size 17.30 nm. The BET analysis of the NiO sample revealed mesoporous NiO nanoparticles with a specific surface area (SBET) of 29.08 m2/g and a narrow distribution of pore sizes. The catalytic performance of NiO and NiC2O4 catalysts studied for the CO2 methanation in tubular packed bed reactor at 150–550 °C and 1 atm. The reduced NiO nanoparticles exhibited more catalytic activity than the decomposed NiC2O4 catalyst. At 380 °C, 1 atm, and gas hourly space velocity (GHSV) of 9000 mL g−1 h−1, the reduced NiO nanoparticle catalyst showed high catalytic activity, with a maximum CO2 conversion of 85.54 %, 99 % CH4 selectivity, and 84.69 % CH4 yield. Furthermore, the NiO nanoparticle catalyst demonstrated excellent stability after 12 h of streaming at 380 °C. [ABSTRACT FROM AUTHOR]

Strong metal‐support interactions (SMSI) featuring the formation of encapsulation overlayer around metal nanoparticles has drawn much attention in heterogeneous catalysis. Recent years, various novel SMSI phenomena have been observed and the nature of SMSI also has been revealed with the improvement of characterization techniques. Understanding the SMSI effect could deepen the insight into the structure‐activity relationship of metal‐supported catalysts, and rationally guide the design of special metal‐interface sites to manipulate catalytic behavior in chemical reaction. In this review, the research progress of SMSI and its application in heterogeneous COx hydrogenation are briefly surveyed, with emphasis on the advanced characterization, manipulation strategy and specific role of SMSI in Fischer‐Tropsch synthesis process, CO2 methanation and Reverse Water Gas Shift reaction. The current challenges and perspectives for the development of SMSI are also discussed. [ABSTRACT FROM AUTHOR]

The production of methane from the methanation reaction between H2 and CO2, also known as the Sabatier reaction, is one way to diversify the global energy matrix, providing a use for CO2. This work evaluates the performance in this reaction of Ni catalysts supported on type MCM‐41 silica, synthesized y a wet impregnation method. Catalytic tests were performed for 2.5 h under atmospheric pressure. The reaction variables considered were the catalyst nickel mass content (5% and 10%), temperature (T = 400 and 550°C), reactant ratio (H2/CO2 = 4 and 2.5), and space velocity (VHSV = 5 and 10 L g−1 h−1). The catalysts were characterized by Brunauer–Emmett–Teller (BET), X‐ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive x‐ray spectroscopy (EDS) analyses before the reactions, and by thermogravimetric analysis (TGA), SEM, and EDS analyses after the reactions. The reaction variables were evaluated using an experimental design with 2 factors and 4 variables, in order to determine the effects of the reaction conditions on catalyst selectivity, reactant conversion, and reaction yields in terms of CH4 and CO. The best result was obtained using a reactant ratio of 2.5, space velocity of 5 L g−1 h−1, and reaction temperature of 550°C, resulting in 93.7% selectivity for methane, 69.4% CO2 conversion, 74% H2 conversion, and methane yield of 20.69%. Findings show Ni/Si‐MCM‐41 catalyst's applicability in methanation, advancing CH4 production technology, and addressing local demand while reducing CO2 emissions. [ABSTRACT FROM AUTHOR]

Integrated carbon capture and conversion (ICCC) is a promising technology to achieve cost‐effective carbon capture, usage, and storage. The development of efficient dual‐functional materials (DFMs) is crucial for advancing ICCC in industrial applications. Herein, a series of NiMg2−xCaxAl‐hydrotalcite (x = 0, 0.5, 1, 1.5, 2) DFMs are prepared and applied to integrated CO2 capture and methanation. Characterization results illustrate that magnesium stabilizes the porous structure of hydrotalcite, and calcium significantly modulates surface basicity. Codoping of Mg and Ca yields merits of both functions and leads to increased methanation efficiency. By optimizing the catalyst and operating conditions, NiMg0.5Ca1.5Al‐hydrotalcite exhibits an excellent CO2 adsorption capacity of 313 μmol g−1DFM and methane yield of 225 μmol g−1DFM with almost full selectivity toward methane at 320 °C. NiMg0.5Ca1.5Al‐hydrotalcite also exhibits good cyclability at 320 °C under ambient pressure. Overall, Mg and Ca codoped hydrotalcite offers a promising approach to construct bifunctional materials for efficient integrated CO2 capture and in situ methanation. [ABSTRACT FROM AUTHOR]

A solution combustion synthesis (SCS) process to prepare nickel catalyst over bentonite (NiO/Ben) is reported. Compared to the traditional impregnation method, NiO/ben produced by SCS has smaller nickel particle size and higher dispersion. With a metal loading of 20 wt%, the afforded NiO/Ben demonstrates excellent catalytic activity for CO2 methanation in a dielectric barrier discharge reactor. In certain discharge conditions (H2:CO2 ratio of 5 in feed gas, discharge input power of 45 W, and gas hourly space velocity of 11 320 h−1), CO2 conversion and CH4 selectivity are as high as 55.8% and 84.6%, respectively. Under the conditions of plasma configuration, the strong interaction between the nickel species and the support plays an important role in the CO2 methanation process. [ABSTRACT FROM AUTHOR]

Methane, the simplest hydrocarbon, has a high energy density and is widely used as chemical feedstocks or fuels. Converting CO2 to methane through electrochemical reduction offers a promising strategy for managing the global carbon balance, but is a challenge due to the lack of effective electrocatalysts. Herein, the Co single atom catalyst supported by MoS2 antisite defect (Co‐MoS2) is designed from both the activity and selectivity aspects. By virtue of i) moderately electron‐deficient state (Coδ+) ensuring efficient CO2 activation and HER suppression; ii) the strong adsorption capability for intermediate enhancing selectivity; iii) the single atomic active site avoiding the formation of C2 products, Co‐MoS2 could selectively convert CO2 to CH4 with a limiting potential of −0.45 V vs. RHE, which outperforms most of the present catalysts, and is expected to be a promising substitution for Cu‐based catalysts. [ABSTRACT FROM AUTHOR]

Denitrogenative organic transformations and related reactions are a class of significant approaches for carrying out unusual C−C/C‐heteroatom (C−O, C−N, C−S) bond‐forming reactions that are usually promoted by Ru, Ir, Pd, Ni, and Cu metal catalysts. In this trait, numerous methods were adopted to synthesize several pharmaceutically valuable N‐ and O‐containing heteroaromatics using 1,2,3‐benzotriazin‐4(3H)‐one as an electrophilic coupling partner. This review involves the recent achievements related to the metal/organo‐catalyzed thermal and visible‐light mediated denitrogenative approaches with 1,2,3‐benzotriazin‐4(3H)‐ones towards the synthesis of imperative N‐heteroaromatic compounds. In addition, metal and oxidant‐free ortho‐functionalization of benzotriazinones by using suitable nucleophilic partners have been discussed. In particular, the most novel methods employing Ni and Pd metal catalysts that have emerged are exhibited. Specific attention has been paid to offering the detailed mechanistic pathway to explain the role of metal catalysts and the mechanism in the absence of metal catalysts in the denitrogenative reactions under a thermal/visible light medium. [ABSTRACT FROM AUTHOR]

Current space missions to Luna and Mars are considering to use the resources, which can be found on‐site at the destination. This strategy named in‐situ resource utilization (ISRU) saves valuable pay‐load capacities during the rocket launch from the earth surface. Specifically, in mars missions it is intended to produce the necessary rocket fuel CH4 for the back‐transit to earth via water electrolysis and subsequent CO2 methanation. The present study elaborates this concept and examines the question if polymeric reactors are feasible for heterogeneously catalyzed reactions in applications beyond earth. The study aims at providing a theoretical backbone for a proof‐of‐concept. The evaluation is conducted theoretically by design considerations and adds experimental results to show the general feasibility of polymeric reactors for applicable reaction conditions. [ABSTRACT FROM AUTHOR]

Transitioning from fossil fuels to renewable energy sources is demanded due to the gradual depletion of petroleum oil/gas and the environmental impact of carbon dioxide (CO2) emissions into the atmosphere. Electrocatalytic and photocatalytic CO2 reduction to methane (CH4) using renewable energy sources is crucial for sustainable chemical/fuel production and greenhouse gas reduction. In recent years, extensive research has focused on understanding the fundamental aspects of the two approaches, such as reaction mechanisms and active sites, and exploring/designing novel catalytic materials. This review initially discusses the reaction fundamentals, including performance evaluation indexes, reactors, and mechanisms, to understand the catalytic reactions. Subsequently, various catalyst preparation strategies and characterization methods are summarized, trying to outline the catalyst design principle based on the obtained understanding of the reaction mechanisms. Finally, research challenges and perspectives for future development in this area are discussed and presented. It is expected to provide a comprehensive understanding of the photo/electrocatalytic CO2 methanation, valuable knowledge to novice researchers, and a helpful reference for future research endeavors. [ABSTRACT FROM AUTHOR]

The catalytic hydrogenation of CO2 to methane is one of the highly researched areas for the production of chemical fuels. The activity of catalyst is largely affected by support type and metal‐support interaction deriving from the special method during catalyst preparation. Hence, we employed a simple solvothermal technique to synthesize Ni‐based catalysts with different supports and studied the support role (CeO2, Al2O3, ZrO2, and La2O3) on structure‐activity relationships in CO2 methanation. It is found that catalyst morphology can be altered by only changing the support precursors during synthesis, and therefore their catalytic behaviours were significantly affected. The Ni/Al2O3 with a core‐shell morphology prepared herein exhibited a higher activity than the catalyst prepared with a common wet impregnation method. To have a comprehensive understanding for structure‐activity relationships, advanced characterization (e. g., synchrotron radiation‐based XAS and photoionization mass spectrometry) and in‐situ diffuse reflectance infrared Fourier transform spectroscopy experiments were conducted. This research opens an avenue to further delve into the role of support on morphologies that can greatly enhance catalytic activity during CO2 methanation. [ABSTRACT FROM AUTHOR]

Breaking the D4h symmetry in the square‐planar M−N4 configuration of macrocycle molecular catalysts has witnessed enhanced electrocatalytic activity, but at the expense of electrochemical stability. Herein, we hypothesize that the lability of the active Cu−N3 motifs in the N‐confused copper (II) tetraphenylporphyrin (CuNCP) could be overcome by applying pulsed potential electrolysis (PPE) during electrocatalytic carbon dioxide reduction. We find that applying PPE can indeed enhance the CH4 selectivity on CuNCP by 3 folds to reach the partial current density of 170 mA cm−2 at >60 % Faradaic efficiency (FE) in flow cell. However, combined ex situ X‐ray diffraction (XRD), transmission electron microscope (TEM), and in situ X‐ray absorption spectroscopy (XAS), infrared (IR), Raman, scanning electrochemical microscopy (SECM) characterizations reveal that, in a prolonged time scale, the decomplexation of CuNCP is unavoidable, and the promoted water dissociation under high anodic bias with lowered pH and enriched protons facilitates successive hydrogenation of *CO on the irreversibly reduced Cu nanoparticles, leading to the improved CH4 selectivity. As a key note, this study signifies the adaption of electrolytic protocol to the catalyst structure for tailoring local chemical environment towards efficient CO2 reduction. [ABSTRACT FROM AUTHOR]

The nonlinear behavior of CO2 methanation over a Ni‐catalyst is compared to methanol synthesis over a standard Cu/ZnO‐catalyst in a continuous stirred tank reactor (CSTR). Both reactions have received a lot of attention these days for chemical energy storage. Both reactions are exothermic but behave in a different way. CO2 methanation is known to be strongly exothermic, giving rise to multiple steady states. This behavior is induced by the self‐acceleration of the methanation reaction because the heat production of the chemical reaction increases with rising temperature. It is shown that methanol synthesis behaves fundamentally different under the operating conditions usually employed in practice. It is less exothermic but, even more important, the overall heat production of the methanol reaction system decreases with increasing temperature, giving rise to a unique and stable steady state. This insight is obtained with an extension of the classical graphical analysis with heat production and heat removal curves. [ABSTRACT FROM AUTHOR]

Background: Butyl levulinate (BL) was produced by the esterification of levulinic acid (LA) and n‐butanol (BOH) using a sulfonated nanocomposite of titania–zirconia as catalyst. A full factorial design was employed for studying the effects of reaction time, mole ratio and catalyst loading on LA conversion. Results: The synthesised catalyst was subjected to various characterisation techniques such as X‐ray diffraction, Fourier transform infrared spectroscopy, Brunauer–Emmett–Teller measurements, thermogravimetric analysis, temperature‐programmed desorption and scanning electron microscopy–energy dispersive X‐ray analysis indicating the presence of a nanocrystalline structure with good surface area and good stability at the operating temperature. The experimental data were analysed using the response surface method, and a complete quadratic regression model was built. The LA conversion was 85.37% for the optimised reaction conditions of 1:7 mole ratio, a catalyst loading of 1 wt% and a reaction time of 5 h at 110 °C. Based on the Langmuir–Hinshelwood–Hougen–Watson model, a kinetic model was developed. The activation energy was found to be 20.4 ± 0.8 kJ mol−1 from an Arrhenius plot. Reusability and leaching results are also reported. Conclusion: The catalyst exhibited good reusability and stability. Sulfonated TiO2–ZrO2 used to catalyse the reaction between LA and BOH to produce BL has proved to be a good candidate as a green catalyst. The results presented play an important part in directing subsequent research and commercialisation activities aimed at valorising LA to fuel additive. © 2023 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

In‐situ infrared spectroscopy is one of the most effective methods to study the surface species on solid catalysts. Still, it is sometimes difficult to identify the reactive intermediates because spectator species, the catalyst support, and experimental noise also contribute to the total spectra. In this study, we prepared three archetypical Ni/Al2O3 catalysts that showed significantly different catalytic activity and selectivity for CO2 hydrogenation, depending on the calcination and reduction temperature. After detailed characterization, we used a combination of Modulation Excitation‐Phase Sensitive Detection‐Diffuse Reflectance Infrared Fourier Transform Spectroscopy (ME‐PSD‐DRIFTS) and Steady State Isotopic Kinetic Analysis (SSITKA) to show that bicarbonates and formates are key reactive intermediates. Furthermore, we also observe carbonyls on the catalyst with the most metallic character and highest selectivity towards CH4. These results confirm that the hydrogenation of CO2 occurs in an associative and consecutive reaction pathway that is highly structure‐sensitive. In this way, we also demonstrate how the simultaneous collection of spectroscopic and kinetic data during modulated or transient experiments is a powerful tool for investigating solid catalysts under realistic operation conditions. [ABSTRACT FROM AUTHOR]

In recent years, heterogeneous catalysts have led to environment‐friendly transformations with better yields and reusability. Pd, one of the initial metals employed in heterogeneous organic synthesis, suffered from limitations like its high cost. This justifies the need for development of catalysts with abundant, low‐cost metals, which has been receiving a lot of attention in the scientific community. In this work, a bimetallic oxide catalyst, CeO2–ZrO2, is synthesized by a sol–gel route. The structure and morphology of the catalyst are investigated using X‐ray diffraction, scanning electron microscopy, energy‐dispersive X‐ray analysis, thermogravimetric analysis, Brunauer–Emmett–Teller measurements, and temperature‐programmed desorption. It is utilized for obtaining quinoxaline derivatives at room temperature. 2,3‐Diphenylquinoxaline is obtained via a simple condensation reaction between 1,2‐diaminobenzene and 1,2‐diketones, catalyzed by CeO2(50)–ZrO2(50) with 87% yield in 15 min. Quinoxalines are known for their biological and therapeutic activities; hence, they are essential molecules. The biological activity of the synthesized quinoxaline derivatives has been evaluated against bacterial and fungal strains. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Dual‐function materials (DFM) carry out both the CO2 purification and the reaction with H2, to produce CH4, over the same material and in the same equipment. While noble metals like Ru and Rh have traditionally been the focus of DFM research due to their catalytic activity at low temperatures, they are expensive. Therefore, there is strong interest in discovering more cost‐effective yet highly active catalysts. Herein, improved DFMs are developed by directly reducing Ni‐containing hydrotalcites, without prior air calcination, at moderate temperature. This method results in a high dispersion of Ni as well as in high amounts of small and reduced Ni crystallites with low interaction with the support, which are crucial for the improved behavior observed. The most remarkable and novel result is that these materials show superior CH4 productivity than previously reported DFMs. Under the five operation cycles evaluated, these DFMs exhibit a substantial increase in CO2 capture (1.76 mol kg−1 DFM) and CH4 productivity (0.98 mol kg−1 DFM), in the absence of O2 and water. In the presence of 4.5% O2, both CO2 adsorption and CH4 productivity decrease but they still outperform previous DFMs. [ABSTRACT FROM AUTHOR]

Recently, CO2 methanation has become a technique that aims to reduce anthropogenic CO2 emissions by converting CO2 captured from stationary and mobile sources and H2 produced from renewable sources into CH4. Due to their excellent performance‐to‐cost ratio, Ni‐based catalysts were frequently used in such conversions. The main drawbacks, however, are that Ni has the propensity to aggregate and deposit carbon during the high‐temperature reaction. These issues can be partially resolved by including a support (e.g., MOF, zeolite, activated carbon, etc.) and a second transition metal (e.g., Mo, Co, or Fe) in Ni‐based catalysts. Therefore, the activity of Ni‐based catalysts at low temperatures needs to be improved. In this study, a series of mesoporous activated carbon (AC) supported bimetallic Ni–Mo catalysts (Ni–xMo/AC, Ni = 13 wt.%, x = 5, 7, 9, 11 wt.%) were synthesized using the incipient wetness impregnation method. The effect of Mo content on the catalyst's activity was examined in a fixed‐bed reactor. At 250–650°C, 1‐atmosphere pressure, gas hourly space velocity (GHSV): 1200 mL h−1 g−1, and H2/CO2 ratio: 4:1, the catalytic efficiency of these catalysts was examined. The catalysts were analyzed using transmission electron microscopy (TEM), X‐ray photoelectron spectroscopy (XPS), X‐ray powder diffraction (XRD), N2‐physisorption, and scanning electron microscopy/energy dispersive X‐ray spectroscopy (SEM‐EDX). Ni–7%Mo/AC catalyst showed the lowest carbon deposition rate, superior stability, and the best activity. The addition of Mo can improve the heat resistance of the Ni/AC catalyst and the interaction between the metal nickel and the support, which prevents the sintering of the catalyst. © 2023 Society of Chemical Industry and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Rational design of low‐cost and efficient transition‐metal catalysts for low‐temperature CO2 activation is significant and poses great challenges. Herein, a strategy via regulating the local electron density of active sites is developed to boost CO2 methanation that normally requires >350 °C for commercial Ni catalysts. An optimal Ni/ZrO2 catalyst affords an excellent low‐temperature performance hitherto, with a CO2 conversion of 84.0 %, CH4 selectivity of 98.6 % even at 230 °C and GHSV of 12,000 mL g−1 h−1 for 106 h, reflecting one of the best CO2 methanation performance to date on Ni‐based catalysts. Combined a series of in situ spectroscopic characterization studies reveal that re‐constructing monoclinic‐ZrO2 supported Ni species with abundant oxygen vacancies can facilitate CO2 activation, owing to the enhanced local electron density of Ni induced by the strong metal‐support interactions. These findings might be of great aid for construction of robust catalysts with an enhanced performance for CO2 emission abatement and beyond. [ABSTRACT FROM AUTHOR]

Cobalt‐based catalysts are well‐known to convert syngas into a variety of Fischer–Tropsch (FTS) products depending on the various reaction parameters, in particular particle size. In contrast, the reactivity of these particles has been much less investigated in the context of CO2 hydrogenation. In that context, Surface organometallic chemistry (SOMC) was employed to synthesize highly dispersed cobalt nanoparticles (Co‐NPs) with particle sizes ranging from 1.6 to 3.0 nm. These SOMC‐derived Co‐NPs display significantly different catalytic performances under CO2 hydrogenation conditions: while the smallest cobalt nanoparticles (1.6 nm) catalyze mainly the reverse water‐gas shift (rWGS) reaction, the larger nanoparticles (2.1–3.0 nm) favor the expected methanation activity. Operando X‐ray absorption spectroscopy shows that the smaller cobalt particles are fully oxidized under CO2 hydrogenation conditions, while the larger ones remain mostly metallic, paralleling the observed difference of catalytic performances. This fundamental shift of selectivity, away from methanation to reverse water‐gas shift for the smaller nanoparticles is noteworthy and correlates with the formation of CoO under CO2 hydrogenation conditions. [ABSTRACT FROM AUTHOR]

Solar‐driven photothermal conversion of carbon dioxide (CO2) to methane (CH4) is a promising approach to remedy energy shortage and climate changes, where highly efficient photothermal catalysts for CO2 methanation urgently need to be designed. Herein, nickel‐based catalysts (Ni/ZrO2) derived from metal–organic frameworks (MOFs) are fabricated and studied for photothermal CO2 methanation. The optimized catalyst 50Ni/ZrO2 achieves a stable CH4 production rate of 583.3 mmol g−1 h−1 in a continuous stability test, which is almost tenfold higher than that of 50Ni/C‐ZrO2 synthesized via commercial ZrO2. Physicochemical properties indicate that 50Ni/ZrO2 generates more tetragonal ZrO2 and possesses more oxygen vacancies (OVs) as well as enhanced nickel‐ZrO2 interaction. As a result, 50Ni/ZrO2 exhibits the strong abilities of light absorption and light‐to‐heat conversion, superior adsorption capacities of reactants (H2, CO2), and an intermediate product (CO), which finally boosts CH4 formation. This work provides an efficient strategy to design a photothermocatalyst of CO2 methanation through utilizing MOFs‐derived support. [ABSTRACT FROM AUTHOR]

The large‐scale deployment of CO2 electroreduction is hampered by deficient carbon utilization in neutral and alkaline electrolytes due to CO2 loss into (bi)carbonates. Switching to acidic media mitigates carbonation, but suffers from low product selectivity because of hydrogen evolution. Here we report a crown ether decoration strategy on a Cu catalyst to enhance carbon utilization and selectivity of CO2 methanation under acidic conditions. Macrocyclic 18‐Crown‐6 is found to enrich potassium cations near the Cu electrode surface, simultaneously enhancing the interfacial electric field to stabilize the *CO intermediate and accelerate water dissociation to boost *CO protonation. Remarkably, the mixture of 18‐Crown‐6 and Cu nanoparticles affords a CH4 Faradaic efficiency of 51.2 % and a single pass carbon efficiency of 43.0 % toward CO2 electroreduction in electrolyte with pH=2. This study provides a facile strategy to promote CH4 selectivity and carbon utilization by modifying Cu catalysts with supramolecules. [ABSTRACT FROM AUTHOR]

Ce‐promoted Ni catalysts were developed and applied in a CO methanation reaction. The 10%Ni/SiO2 catalyst exhibits poor initial CO conversion (32.8%) and rapid deactivation with the highest methane selectivity during CO the methanation reaction. In contrast, the 4%Ce–10%Ni/SiO2 catalyst shows dramatically increased initial CO conversion, which is up to 90.7%. Additionally, the apparent activation energy, Ea value, of 4%Ce–10%Ni/SiO2 was calculated to be 102.2 kJ/mol according to the Arrhenius equation, which is much lower than that of the 10%Ni/SiO2 catalyst, which was 139.1 kJ/mol. Based on various characterization results, it is found that the added Ce significantly improves the dispersion of the supported nickel, suppresses the sintering of nickel particles, and forms more adsorbed CO species of three‐fold carbonyl species, resulting in higher CO conversion and good stability during the CO methanation reaction. [ABSTRACT FROM AUTHOR]

Fossil fuel depletion and environmental impacts caused by greenhouse gas emissions such as CO2 are significant issues securing nature preservation within a sustainable economy. CO2 methanation is a promising process to mitigate CO2 emissions and reuse it to produce CH4, serving as fuel, chemical feedstock, and energy source. A series of LDH‐derived Ni‐Al catalysts promoted by Li, Mg, Ca, and La were prepared via co‐precipitation. Characterization by N2 physisorption, X‐ray diffraction (XRD) and photoelectron spectroscopy (XPS), as well as thermal techniques such as temperature programmed reduction (H2‐TPR), desorption (CO2‐TPD, H2‐TPD), and oxidation (TPO) analyses were performed. Low‐temperature catalytic tests (200–400 °C) revealed that alkali metal modification improves performance even at 200 °C, where the Ni55Ca11Al33 catalyst achieved 74 % CO2 conversion with 100 % CH4 selectivity by enhancing basicity and metal‐support interaction, high Ni dispersion and small crystallite sizes, providing proper sites to adsorb and activate CO2. Moreover, the catalysts presented excellent resistance to deactivation, maintaining high stability during 10 h on stream. These results prove that Ni‐Al mixed oxides, LDH‐derived catalysts performances can be further improved by incorporating alkali metals into less energy‐spending, low‐temperature CO2 methanation processes. [ABSTRACT FROM AUTHOR]

Integrated energy system (IES) is one of the ways to realize energy saving and emission reduction. Facing the crisis of fossil energy depletion and the challenge of global warming, low‐carbon technology and market economic guidance mechanism have an important impact on the low‐carbon operation of integrated energy system (IES). In this study, IES with carbon capture and utilization (CCU) technology is established, the carbon emission model based on life cycle theory is built for the input energy and energy system of IES, and the ladder carbon trading mechanism is considered in the market economy to establish the low‐carbon economic optimization model of IESs. A system combining carbon capture technology and power to gas can effectively consume new energy sources and provide energy dispatch flexibility. The ability to capture greenhouse gases generated by energy units reduces the system's carbon emissions. Based on the IES low carbon economy model, the model is analyzed with examples to analyze the correlation between different carbon trading prices and IES low carbon economy transport. We analyze the impact of CCU technology inputs on the low‐carbon nature of IES. The study proposes an IES dispatching model based on life cycle assessment and CCU technology to provide a new strategy for the operation of IESs and a new method for other energy systems to reduce low carbon emissions. [ABSTRACT FROM AUTHOR]

CeO2–nanorod support was synthesized by hydrothermal method and different manganese oxides (MnO, MnO2, and Mn2O3) were impregnated over support by the wet‐impregnation forming MnO/CeO2‐NR, MnO2/CeO2‐NRm and Mn2O3/CeO2‐NR. The physico‐chemical properties of the as‐prepared catalysts were analyzed using x‐ray diffraction (XRD), Brunauer–Emmett–Teller (BET) surface area, x‐ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), scanning electron microscope–energy‐dispersive x‐ray spectroscopy (SEM–EDX), hydrogen‐temperature‐programmed reduction (H2‐TPR), and Raman spectroscopy. These catalysts were further analyzed for NO reduction using NH3 as a reducing gas in the temperature range of 50 to 450°C. The results confirmed that MnO2/CeO2‐NR gave the maximum NO conversion (65%) and N2 selectivity (89%) among all catalysts. Further, MnO2/CeO2‐NR catalyst was studied for the effect of MnO2 loading and more than 90% NO conversion and N2 selectivity were obtained in the temperature range of 250 to 300°C. [ABSTRACT FROM AUTHOR]

In the present work, three zeolite‐beta based catalysts with post impregnation of aluminum are evaluated for conversion of rice husk to furfural at atmospheric pressure in the presence of sodium chloride as promoter. The synthesized catalysts were characterized by nitrogen adsorption–desorption isotherm, scanning electron microscopy, X‐ray diffraction, and pyridine Fourier transform infrared spectroscopy. The activity of in house synthesized/modified catalysts is studied at preliminary optimized reaction conditions of 375°C and 47 min with variation in feed/catalyst/promoter ratio. Purity and yield of furfural was obtained by gas chromatography analysis with flame ionization detector in a batch reactor. Results shows that zeolite beta with 5 wt % post aluminum impregnation gave highest yield of bio‐oil (60.3 wt%) with 88% selectivity toward furfural in the presence of sodium chloride (5 wt% of feed) and sulfuric acid (10 wt% of feed). [ABSTRACT FROM AUTHOR]

The article discusses the importance of catalysts and reactors under dynamic conditions for energy storage and conversion in the context of decarbonizing the industry. It highlights the challenges posed by the fluctuating availability of renewable energy sources like wind and solar power and the need for rapid energy storage solutions. The interdisciplinary approach involving physics, chemistry, and engineering is emphasized, with a focus on catalysis to transform electrical energy into high-energy reactive molecules. The article also mentions the recent developments presented at EUROPACAT 2023 and invites further discussion on the topic at EUROPACAT 2025. [Extracted from the article]

Ni‐based catalysts have been widely studied in the hydrogenation of CO2 to CH4, but selective and efficient synthesis of higher alcohols (C2+OH) from CO2 hydrogenation over Ni‐based catalyst is still challenging due to successive hydrogenation of C1 intermediates leading to methanation. Herein, we report an unprecedented synthesis of C2+OH from CO2 hydrogenation over K‐modified Ni−Zn bimetal catalyst with promising activity and selectivity. Systematic experiments (including XRD, in situ spectroscopic characterization) and computational studies reveal the in situ generation of an active K‐modified Ni−Zn carbide (K‐Ni3Zn1C0.7) by carburization of Zn‐incorporated Ni0, which can significantly enhance CO2 adsorption and the surface coverage of alkyl intermediates, and boost the C−C coupling to C2+OH rather than conventional CH4. This work opens a new catalytic avenue toward CO2 hydrogenation to C2+OH, and also provides an insightful example for the rational design of selective and efficient Ni‐based catalysts for CO2 hydrogenation to multiple carbon products. [ABSTRACT FROM AUTHOR]

The methanation of CO2 has been actively pursued as a practical approach to mitigating global climate change. However, the complexity of the catalyst development process has hindered the development of new catalysts for CO2 methanation; as a result, few catalysts are commercially available. Herein, a multifunctional self‐catalytic reactor (SCR) is prepared via metal 3D printing and selective electrochemical dissolution as a method to not only simplify the catalyst development process but also fabricate active catalysts for CO2 methanation. The combination of metal 3D printing and selective electrochemical dissolution is demonstrated as a feasible method to prepare active catalysts for the methanation of CO2 in a short time. In addition, the use of an electrochemical method enables the formation of galvanic cells on the SCR; these cells continuously generate active sites via self‐dissolution during a simple refresh process, resulting in high reusability of the SCR. The proposed method represents a new facile technique to fabricate highly reusable catalysts that exhibit superior performance for CO2 methanation, and the results provide a guideline for preparing metal 3D‐printed catalysts that will satisfy industrial demand. [ABSTRACT FROM AUTHOR]

The process of biological methanation in bubble column reactors was established in single reactors and cascade by the joint research project BioStore (SAB, FKZ: 100310024). In order to increase the efficiency of the process, energy‐intensive components such as agitators or gas separation were not used as far as possible. Furthermore, the gas injection system was optimized as a performance‐determining component in order to maximize conversion and methane rate. As a result, methane content of over 96 vol % and a methane formation rate of 2 L/(L × d) were achieved in continuous operation. This fulfils a technical requirement for direct injection into the natural gas grid. [ABSTRACT FROM AUTHOR]