Steam Reforming Research Articles

The mitigation of carbon deposition for Ni-based catalyst in CO2 reforming of methane: A combined experimental and DFT study

The dry reforming of CH4 (DRM) reaction can simultaneously convert two greenhouse gases CO2 and CH4 into high valued syngas. Nickel-based catalysts have been widely studied because of the low cost and high activity. However, carbon deposition making the deactivation of Ni-based catalyst is the main challenges for DRM reaction. This review illustrates DRM reaction mechanism and the causes of carbon deposition, as well as the resistance strategies of carbon deposition for Ni-based catalyst. The deposited carbon can be restrained by adjusting the size of Ni particles, introduction of promoters, reasonable design of support, controlling the reaction process and employing the confinement effect of the catalysts. The valuable insights are garnered for the further augmentation and optimization of the anti-carbon performance of catalysts by DFT and microkinetic. This work provides a tutorial for designing Ni-based catalysts with high anti-carbon deposition properties for DRM reaction.

Highly porous Ni/MgO-ZrO2 catalysts for dry reforming of methane and the effects of MgO addition on the mechanisms

Dry reforming of methane (DRM) is a promising pathway to convert greenhouse gas into syngas. However, the commonly used Ni based catalysts suffer deactivation due to severe sintering and coking. In this paper, a series of porous Ni/MgO-ZrO2 catalysts (5Ni/xM(1-x)Z, x = 0, 20, 40, 60, 80 wt%, respectively) with high specific surface area were synthesized by a facile combustion method followed by incipient impregnation. It is found that the appropriate amount of MgO (40 %) addition in ZrO2 favors high porosity and high specific area. More MgO enhances the basicity of the catalyst as well as the metal-support interaction (MSI) by the formation of NiO-MgO solid solution, thus improving DRM activity and coking resistance. However, excessive MgO addition leads to over-strong MSI and lower porosity, resulting in lower DRM activity. The catalyst with 40 % MgO addition (5Ni/40M60Z) exhibits the best activity (conversions of CH4 ∼ 76 %, CO2 ∼ 83 %) and stability (>50 h) at high GHSV = 96000 ml/gcat·h and 750 °C. in situ DRIFTS reveals the mechanism that MgO addition improves DRM activity and stability. Compared with ZrO2 where CO2 adsorbs as monodentate carbonate, CO2 tends to adsorb on 40 %MgO-60 %ZrO2 as bidentate carbonate and then easily transfer to more stable intermediate bidentate formate, thus improving DRM activity and coking resistance. This study provides new insights on the role of Mg addition in Ni/MgO-ZrO2 DRM catalysts.

Life cycle assessment and techno-economic analysis of maleic anhydride hydrogenation to 1,4-butanediol through biomass gasification coupling with chemical looping hydrogen production

Maleic anhydride hydrogenation is an important method to produce 1,4-butanediol. However, a large amount of H2 is needed for this method. Thus, novel processes to produce 1,4-butanediol from maleic anhydride were proposed using biomass gasification combined with chemical looping hydrogen generation technology (BGCLHP route) and natural gas steam reforming (NGSR route) to provide maleic anhydride hydrogenation with H2. Life cycle assessment was carried out, indicating that the BGCLHP route has a smaller environmental influence than the NGSR route. Additionally, techno-economic analysis was also studied to analyze the capital and operating investment, demonstrating the feasibility of the proposed route with existing technologies. Utilizing municipal solid waste as raw material, the minimum 1,4-butanediol selling price of the BGCLHP route was 2245 $/tonne, indicating it has a better economic performance. Based on the above analysis, the BGCLHP route has the potential to contribute to a more eco-friendly and economically sustainable 1,4-butanediol industry.

Integrated syngas biorefinery for manufacturing ethylene, acetic acid and vinyl acetate

The paper presents the design of an innovative process for manufacturing sustainable biochemicals, as acetic acid, ethylene and vinyl acetate monomer (VAM), in an integrated syngas biorefinery using renewable feedstock as biomethane and captured CO2. The work is supported by full design and simulation of six plants imbedded in a large process: syngas1 H2/CO 2:1 by catalytic partial oxidation of methane, syngas2 H2/CO 1:1 by dry methane reforming, methanol, acetic acid by carbonylation, ethylene and vinyl acetate. A key contribution is the development of a novel acetic-acid-to-ethylene process starting from syngas. This consists of catalytic hydrogenation of acetic acid (exothermic) followed by catalytic ethanol dehydration (endothermic). The thermal integration of reactors leads to low energy process and superior sustainability measures versus petrochemical and methanol-to-olefin processes. The comprehensive simulation of the integrated biorefinery allows getting consistent mass and energy balances, performing energy analysis and capital cost estimation, and finally delivering reliable sustainability measures. Based on syngas the carbon-yield, mass-yield, carbon footprint (kg CO2/kg product) and energetic requirement (MJ/kg) are 78.6%, 34.7%, 1.6 and 11.2 for ethylene, and 80.8%, 46.8%, 1.5 and 11.9 for VAM. At high biomethane price the ethylene may be costly but manufacturing the higher value VAM is fully profitable.

Facilely Synthesized CeNi1-xCoxO3 Perovskite Catalyst for Combined Steam and CO2 Reforming of Methane

Facilely Synthesized CeNi1-xCoxO3 Perovskite Catalyst for Combined Steam and CO2 Reforming of Methane

Twisted BiOCl Moiré Superlattices for Photocatalytic Chloride Reforming of Methane.

Solar-driven conversion of CH4 into value-added methyl chlorides and H2 with abundant chloride ions offers a sustainable CH4 reforming strategy but suffers from inefficient Cl- activation and severe e--h+ recombination in traditional photocatalysts. Herein, we demonstrate that BiOCl moiré superlattices with a 11.1° twist angle are highly efficient for photocatalytic CH4 reforming into CH3Cl and H2 with NaCl. These moiré superlattices, featuring misalignment-induced tensile strains, destabilize surface Bi-Cl bonds, facilitating a hole-mediated MvK-analogous process to activate lattice Cl into reactive •Cl for CH4 chlorination. Meanwhile, their twisted stacking configurations reinforce interlayer electronic coupling and thus accelerate out-of-plane carrier transfer. Along with surface anchoring of single-atom Pt sites for H2 evolution, the resulting Pt1/BiOCl moiré superlattices deliver a CH3Cl yield of 53.4 μmol g-1 h-1 with an impressive selectivity of 96% under visible light. This study highlights the potential of lattice engineering in two-dimensional photocatalysts to regulate structural strains and carrier dynamics for the decentralized reforming of CH4.

Ni-Co Bimetallic Catalysts Supported on Mixed Oxides (Sc-Ce-Zr) for Enhanced Methane Dry Reforming.

Dry methane reforming (DRM) presents a viable pathway for converting greenhouse gases into useful syngas. Nevertheless, the procedure requires robust and reasonably priced catalysts. This study explored using cost-effective cobalt and nickel combined into a single catalyst with different metal ratios. The reaction was conducted in a fixed reactor at 700 °C. The findings indicate that the incorporation of cobalt significantly enhances catalyst performance by preventing metal sintering, improving metal dispersion, and promoting beneficial metal-support interactions. The best-performing catalyst (3.75Ni+1.25Co-ScCeZr) achieved a good conversion rate of CH4 and CO2 at 46.8 %, and 60 % respectively after 330 minutes while maintaining good stability. The TGA and CO2-TPD analysis results show that the addition of Co to Ni reduces carbon formation, and increases the amount of strong basic sites and isolated O2- species, and the total amount of CO2 desorbed. These results collectively highlight the potential of cobalt-nickel catalysts for practical DRM applications and contribute to developing sustainable energy technologies.

Numerical Study of Complex Heat Transfer and Aerodynamics in a Tube Furnace with a Flat Fuel Combustion Mode

The object of the study is a tubular furnace for steam reforming of natural gas. The channel walls are formed by a refractory lining and a tubular screen with a known temperature. The chamber volume is filled with a selectively radiating, absorbing and weakly scattering medium of gaseous fuel combustion products. The research method is based on the numerical solution of a system of two-dimensional integro-differential equations of radiative gas dynamics, closed by a two-parameter model of turbulent convection. It is shown that when burners are located on the side walls of the radiation chamber, a significant restructuring of the heat flux distribution occurs. A decrease in the chamber width is accompanied by an increase in both radiant and convective heat fluxes to the tubular screen.

Optimizing Co-generation performance of reactivity controlled compression ignition engines with solar steam reforming of methanol; a thermoeconomic, economic and exergoenvironmental analysis

Reactivity-controlled compression ignition engines have garnered significant interest for their potential to deliver enhanced performance, particularly in environmental aspects. This study investigates the performance of such engines within a co-generation framework for simultaneous power and cooling production. Low reactivity fuel for the engine is derived from solar steam reforming of methanol, with waste heat recovered through a supercritical CO2 cycle and an absorption refrigeration cycle. The designed configuration undergoes comprehensive analysis encompassing thermodynamic, economic, and exergoenvironmental assessments, including parametric analysis. Optimal engine performance is evaluated through computational fluid dynamics, thermodynamic, and exergoenvironmental analyses across various syngas compositions and reforming conditions. Results indicate that a syngas portion of 60% at a reforming temperature and CH3OH to H2O ratio of 200 °C and 1.2 yields optimal engine performance. Besides, the inlet temperature of the CO2 turbine exhibits the greatest impact on co-generation performance. At the optimal state, co-generation's power and cooling load generation reach 467.8 kW and 225 kW, with a unit cost of 53.89 $/GJ, an exergy efficiency of 38.14%, a sustainability index of 1.622, and an exergoenvironmental impact index of 1.607.

Breakthroughs in Low-Cost Hydrogen Production Methods for Fuel Cells

Traditional hydrogen production, like steam methane reforming (SMR), is limited by high greenhouse gas emissions and fossil fuel dependency. However, integrating renewable energy with innovative production technologies offers a more sustainable and cost-effective pathway. Electrolysis, powered by renewable sources such as wind and solar, is a promising method that has seen efficiency improvements through advancements in proton exchange membrane (PEM) and anion exchange membrane (AEM) technologies. Additionally, research into thermochemical water splitting, which utilizes high-temperature heat from solar or nuclear energy, presents a scalable alternative for industrial hydrogen production. Biological hydrogen production using microorganisms, such as algae and bacteria, offers further innovation by leveraging natural processes for hydrogen generation. The integration of renewable energy into hydrogen production not only lowers costs but also provides an effective means of energy storage, contributing to grid stability and reducing reliance on fossil fuels. This paper explores recent breakthroughs in low-cost hydrogen production methods, essential for advancing the hydrogen economy and promoting fuel cells as a clean energy solution.

Modeling of Dry Reforming of Methane Using Artificial Neural Networks

Modeling of Dry Reforming of Methane Using Artificial Neural Networks

Current hydrogen production methods and their economic and environmental analysis

As global temperatures continue to rise due to the extensive use of fossil energy sources, concerns about the environment continue to deepen. Accelerating the energy transition is a major trend, and countries are continuously increasing the proportion of clean energy in the energy supply. Hydrogen energy is one of the most promising clean energy sources and a hot research topic in various countries. Hydrogen production is a key step in the use of hydrogen energy, this paper focuses on the current mainstream hydrogen production methods including electrolysis of water, solar decomposition of water, biomass hydrogen production, nuclear technology, steam methane reforming, coal gasification, methane pyrolysis, etc. And the economic and environmental benefits of each method. According to studies, the mainstream method of producing hydrogen today involves burning fossil fuels, and more recent methods—like the electrolysis of water—need a lot more testing and development before they can be used extensively. The implementation of CCS or CCUS technology can considerably lower the carbon emissions of the hydrogen production process when it comes to hydrogen produced from fossil fuels, but doing so will result in higher energy costs and hydrogen production costs. This paper is expected to support future research directions and help governmental decision-making in the energy transition.

Atomically Dispersed Ru Species Induced by Strong Metal-Support Interaction for Electrochemical Methane Reforming.

During the high-temperature oxygen evolution reaction for CO2 electrolysis in solid oxide electrolysis cells (SOECs), the key elementary process of O2- transfer is restricted by the high anodic oxygen pressure thermodynamically, thus requiring a high external voltage [open-circuit voltage (OCV)] to drive the electrolysis reaction. Herein, electrochemical CH4 reforming is introduced to the SOEC anode, which remarkably lowers the anodic oxygen pressure and OCV, finally reducing the energy demand from 3.12 to 0.11 kW h per cubic meter of CO. Meanwhile, atomically dispersed Ru species is anchored on the anode surface due to the strong metal-support interaction, which exhibits superior CH4 reforming activity (90% of CO selectivity) and stability (300 h) to the infiltrated Ru nanoparticles and doped Ru species in the bulk lattice at 600 °C. This work proposes an efficient strategy to boost the SOEC performance thermodynamically and produce value-added chemicals at both the cathode and anode of SOEC simultaneously.

Role of Active Site and CO2-Interacting Surface Species in Dry Reforming of Methane over Strontium Promoted Ni Catalyst Supported by Lanthanum-Zirconia.

In the context of global warming, the dry reforming of methane (DRM) has gained significant attention due to its ability to simultaneously deplete two greenhouse gases, i. e. CH4 and CO2, and generate syngas. Herein, strontium-promoted Lanthanum-zirconia supported Ni catalysts are investigated for DRM and characterized by X-ray diffraction, surface area and porosity, FTIR-RAMAN spectroscopy, and temperature-programmed experiments. The Ni/LaZr catalyst contains formate and oxycarbonate-like CO2-interacting species, while strontium-promoted catalysts have additional ionic CO3 2- species. The current catalyst system of 2 % strontium-promoted Ni/LaZr has active sites derived from three types of NiO: easily reducible, moderately interacted, and strongly interacted. During the DRM reaction over the current system, CO2 is a better oxidant than O2 for removing carbon deposits. Additionally, the catalysts attain higher reducibility under oxidizing gas (CO2) and reducing gas (H2) during the DRM reaction. For optimal hydrogen yield of approximately 60 % within 420 minutes of operation over Ni2Sr/LaZr catalyst, a balance between the population of active site Ni and CO2-interacting surface species is necessary.

Impact of Potassium Addition on the Performance of Ni/MgAl2O4 Catalysts in Steam Reforming of Bio-Oil Model Compounds

Impact of Potassium Addition on the Performance of Ni/MgAl₂O₄ Catalysts in Steam Reforming of Bio-Oil Model Compounds

Dry Reforming of Methane on Low‐Loading Rh Catalysts

Dry reforming of methane (DRM) is a promising catalytic process for converting greenhouse gases (CH4 and CO2) into syngas (CO and H2). This study investigates DRM under moderate conditions (550 °C) using supported ultra‐low loading (0.05 wt%) metal (M) catalysts (M = Rh, Ru, Pt, Pd, Ir, Au, and Ni). The reaction was carried out for 6 h with a flow rate of 30 mL/min for both CH4 and CO2, using 0.10 g of catalyst. Among these catalysts, 0.05 wt% Rh/Al2O3 exhibited the highest DRM activity. The effect of catalyst supports revealed that Al2O3 is the most effective support for 0.05 wt% Rh. The DRM activity of Rh species supported on Al2O3 and SiO2 was compared, and the Rh species on Al2O3 outperformed those on SiO2, indicating Al2O3 enhances the DRM activity of Rh. When comparing the DRM activity of Rh nanoparticles and Rh single atoms, it was suggested that Rh nanoparticles might exhibit superior performance for DRM. Coke deposited on 0.05 wt% Rh/Al2O3 is removed by CO2, maintaining stable catalytic activity. These findings provide valuable insights into the design of catalysts that minimize the use of noble metals in DRM reactions.

Biomimetic low carbonization efficient solar-driven thermochemical energy storage reactor design inspired by the diatoms’ superior photosynthesis capacity

Photon is the energy source that drives solar thermochemistry. Photon-based radiative transfer in the reactor space is an essential mode of energy transfer. However, there often exists mismatch between the radiative and chemical fields in direct solar thermochemical processes, which can lead to ultra-high temperature gradients and high carbonization rates. While, the vicious cycle that exists between high temperature gradients and higher carbonization rates could severely limit the thermochemical efficiency. To improve the efficiency and reduce the temperature gradient and carbonization, inspired by the superior performance of diatom photosynthesis, a biomimetic radiation-regulated reactor is proposed. The paper establishes multi-field model of steam methane reforming, and analyzes the energy conversion processes at pore-scale. In numerical analyses, compared to the conventional reactor, the biomimetic reactor enhances the light forward scattering in fore-end and the backward scattering in rear-end, which increases the light absorption efficiency by 6.8% and reduces the temperature gradient by 41.3%. In experimental investigation, the methane conversion and the solar-fuel efficiency of the biomimetic reactor is 48.6% and 44.0%, which is increased by 11.5% and 10.7% respectively. It also demonstrates high efficiency and stability under long operating conditions. The biomimetic reactor provides a new strategy for industrial solar-driven methane conversion.

Techno-Economic Assessment of Hydrogen Production in Ghana through PV Electrolysis and Biomass Gasification

Abstract The potential to develop a green hydrogen market in Ghana is assessed in this paper. The focus is on biomass gasification and photovoltaic-driven water electrolysis. Using the H2A-Lite model, the technical, economic, and environmental aspects of these technologies are assessed for both current (2023) and future (2040) scenarios. In the current scenario, distributed and centralized Polymer Electrolyte Membrane (PEM) electrolysis gave levelized costs of $5.56/kg and $4.35/kg for hydrogen respectively, while centralized biomass gasification yields the cheapest hydrogen cost at $2.68/kg. The high cost of solar PEM electrolysis is linked to expensive electricity and solar PV, but also to compression, storage, and dispensing costs for distributed systems. By year 2040, a general cost reduction is expected due to cheaper renewable energy and increased efficiency. However, these production methods still face competition from more economical conventional steam methane reforming (SMR) processes having a levelized cost of less than $2/kg H2. The study concludes that a hydrogen development strategy and roadmap for Ghana will be crucial to proceed with hydrogen, setting deployment targets, and engaging stakeholders in promoting the use of hydrogen as an energy carrier while creating new economic opportunities and achieving climate objectives.

Catalytic steam reforming of waste tire pyrolysis volatiles using a tire char catalyst for high yield hydrogen-rich syngas

The production of hydrogen and syngas (H2/CO) from waste tires by pyrolysis catalytic steam reforming was investigated in a two-stage fixed bed reactor. In this study, tire char served as a sacrificial catalyst, facilitating the combination of catalytic steam reforming and char steam gasification reactions. The tire char acted as both a catalyst and a gasification reactant, enhancing the gas product yield. The process parameters investigated were, a reforming temperature range of 700–1000 °C, steam space velocity between 2 and 12 g h−1 g−1char and reaction times of 0.5–2 h. The influence of the parameters on the yield and composition of the product gases and the characteristics of the used catalyst were analyzed in detail. The results indicated that higher temperature and steam space velocity increased H2 and CO yields in the presence of a tire char catalyst. Elemental analysis of the used tire char, surface morphology and pore structure provided insights into the extent of tire char consumption in the reaction. Prolonged reaction time allowed for more thorough reactions between the pyrolysis volatiles and tire char, promoting the production of H2. At a reaction time of 2 h, the H2 yield reached 223 mmol g−1, representing 74 wt% of the maximum hydrogen yield.

Steam reforming of toluene as model compounds of biomass tar by Fe–K-based biochar nano-catalysts at mild temperatures

Development of efficient catalysts for steam reforming of biomass tar is crucial for the widespread application of biomass gasification. In this work, a novel biochar nano-catalyst (BN) is conveniently prepared via one-step catalytic pyrolysis, using K and Fe to adjust the surface structure of the biochar, thereby enhancing the activity for toluene reforming. Fe–K/BN is tested in a fixed-bed reactor for steam reforming of toluene, a model compound of biomass tar, achieving a 100% toluene conversion rate at 650 °C. Fe–K/BN is activated in situ with steam to increase their specific surface area and enhance the O-containing functional groups on the surface, improving toluene adsorption and reforming. Finally, the stability of Fe–K/BN is tested in the simulated syngas, maintaining a 100% toluene conversion rate during a 26-h continuous catalytic reforming experiment. This work provides a promising strategy for the design of an active and stable catalyst for toluene reforming, which has potential for application of tar steam reforming during biomass gasification.