Catalytic Decomposition Of Methane Research Articles

Effect of active metals and process factors on the catalytic decomposition of methane for hydrogen production

Effect of active metals and process factors on the catalytic decomposition of methane for hydrogen production

Carbon–neutral hydrogen production by catalytic methane decomposition: a review

Carbon–neutral hydrogen production by catalytic methane decomposition: a review

Effect of Ni/SiO2 catalyst preparation method on methane decomposition and CO2 gasification cycles

Catalytic methane decomposition is a promising reaction to produce CO2-free hydrogen from methane-rich feedstock with solid carbon as a by-product. Significant research conducted on this reaction to find ways to manage and utilize this solid carbon. In this work, the methane decomposition reaction is followed by Reverse Boudouard Reaction using CO2 feedstock to convert the solid carbon to carbon monoxide, which is a valuable starting component for many chemical applications. Realizing this promising concept would require a catalyst that is efficient for both reactions. Herein, we explored the potential of using solution combustion synthesis (SCS) to make a 5 wt% of Ni supported SiO2 catalyst and benchmarked it versus the conventional impregnation method. The catalyst prepared by SCS showed an improved performance at different temperatures, space velocities, and catalyst pellet sizes. The SCS catalyst successfully completed five repeated cycles reaching up to 38.1 h of stable time on stream operation, whereas the impregnated catalyst was not able to complete the second testing cycle with only 14 h of time on stream operation. A thorough characterization using XRD, H2 and O2 TPR, TEM, SEM, XPS, and Raman spectroscopy were conducted to provide an adequate explanation for the observed performances for both catalysts. The Ni nanoparticles size and distribution, the strength of the metal support interaction, and the nature of graphitic carbon were the key factors affecting the catalytic performance. Insights on how to make an optimal catalyst for this promising process is identified which is a step forward toward making separated H2 and CO streams from methane feedstock and CO2, respectively.

Enhanced production of hydrogen via catalytic methane decomposition on a Pt7-Ni (110) substrate: a reactive molecular dynamics investigation

Abstract Numerous researchers in the energy field are engaged in a competitive race to advance hydrogen as a clean and environmentally friendly fuel. Studies have been conducted on the different aspects of hydrogen, including its production, storage, transportation and utilization. The catalytic methane decomposition technique for hydrogen production is an environmentally friendly process that avoids generating carbon dioxide gas, which contributes to the greenhouse effect. Catalysts play a crucial role in facilitating rapid, cost-effective and efficient production of hydrogen using this technique. In this study, reactive molecular dynamics simulations were employed to examine the impact of Pt7 cluster decoration on the surface of a Ni (110) catalyst, referred to as Pt7-Ni (110), on the rates of methane dissociation and molecular hydrogen production. The reactive force field was employed to model the atomic interactions that enabled the formation and dissociation of chemical bonds. Our reactive molecular dynamics simulations using the Pt7-Ni (110) catalyst revealed a notable decrease in the number of methane molecules, specifically ~11.89 molecules per picosecond. The rate was approximately four times higher than that of the simulation system utilizing a Ni (110) catalyst and approximately six times higher than that of the pure methane, no-catalyst system. The number of hydrogen molecules generated during a simulation period of 150 000 fs was greater on the Pt7-Ni (110) surface than in both the Ni (110) and pure methane systems. This was due to the presence of numerous dissociated hydrogen atoms on the Pt7-Ni (110) surface.

Mechanism on CMD reaction regulated by supports and promoters of Fe-based catalysts

Methane cracking technology for low-carbon energy conversion to produce hydrogen is a key technical approach in the pursuit of fossil energy decarbonization. Catalytic methane decomposition (CMD) is a process that accomplishes the fundamental removal of carbon from fossil energy without oxygen, producing high-quality carbon-based materials and H2. The functionality of supports and promoters was investigated using inorganic metal oxide support Al2O3, supported active metal Fe, and cocatalyst K. The results show that the Al2O3–Fe catalyst achieves the highest CH4 conversion of 65% at 850 °C, with a gas-phase H2 yield of 1189.72 mmol/gFe within 3 h, and a solid-phase carbon yield of 6.32 g/gFe, significantly higher than at 750 °C. The Al2O3–Fe–K catalyst achieves a methane conversion rate of 66.28% at 850 °C for 1.5 h, exhibiting relatively fast deactivation. The Al2O3–Fe catalyst catalyzes the formation of carbon nanotubes (CNTs) through methane cracking, resulting in mainly 'chain-locked' morphology. The promoter K acts on the surrounding metal clusters to influence the dispersion of active metal. The Al2O3–Fe–K catalyst is more favorable for the production of 'bamboo-shaped' carbon nanotubes, suggesting that K has a more significant impact on shaping the CNTs' products.

High-efficiency graphene-coated macroscopic composite for catalytic methane decomposition operated with induction heating

The large-scale production of hydrogen and the direct sequestration of carbon, in solid form, from the decomposition of natural gas could constitute an attractive economic alternative for the production of hydrogen if deactivation by coke or sintering could be mitigated. Here, we report on the use of a 2D graphene-based catalyst with controlled macroscopic shape for the catalytic decomposition of methane (CMD) at medium temperature, ranged from 500 °C to 900 °C, under contactless inductive heating. The presence of a magnetic field seems to have a strong influence on the catalytic performance and allows the maintain of the catalyst stability. Characterizations of the spent catalyst showed that the carbon deposited under inductive heating is in the form of carbon filaments which grow away from the edges or defects of the graphene. This particular growth mode allows one to maintain the catalytic activity of such carbon-based catalyst over longer periods compared to those reported in the literature. These promising results could set a base ground for the develop an industrially and economically viable way to convert natural gas into turquoise hydrogen, using renewable energy and low-cost catalysts, with improved resistance to poisoning by impurities present in the processing charge. The carbon formed could also be effectively use in other downstream applications. The combination of carbon-based catalyst and contactless induction heating could also lead to combined catalytic processes for numerous challenging reactions.

Hydrogen and carbon produced by fluidized bed catalytic methane decomposition

Natural gas or methane-rich gas resources (e.g. digestion biogas) are major fuel sources for heat and power generation. CH4 is furthermore used in petrochemical and chemical reactions (reforming, ammonia, methanol, urea, among others). In these thermal applications, the transformation of methane will release greenhouse gases, as CO2 together with mostly thermal NOx from its combustion. The development of alternative CH4 utilization techniques is important. The Catalytic Methane Decomposition (CMD) operates at near-zero GHG emissions and produces 2 valuable products:CH4→C+2H2∆Hr=74.8kJ/mol20°C,85.5kJ/mol650°CHydrogen can help to partly decarbonize the fossil fuel applications either as a mix with natural gas (Hydrogen Enriched Natural Gas), or applied in fuel cells and industrial thermal processes, such as cement or steel production. The carbon product can be used as a filler or additive. Although different catalysts for the CMD process have been assessed, their high cost and low CH4 decomposition efficiencies are drawbacks. The present research investigates the use of a cheap and efficient catalyst. Fluidized bed CMD experiments using a 12 wt%Fe/Al2O3 catalyst were performed, and CH4 conversion yields of over 80% are obtained at 650 to 700 °C. The carbon formed is of a CNT nature but partly deposits within the catalyst bed, leading to a progressive reduction in H2 yield. Although the CNT can be continuously removed from the bed, a partial thermal regeneration of the catalyst is required. A three-step process was tested and developed. The very low CO2 emission and competitive cost for both H2 and CNT will be proven.

Influence of MgO promoution to Ni-based composites in hydrogen production methane decomposition process

Catalytic decomposition of methane is a promising process that allows the simultaneous production of hydrogen and carbon nanomaterials with no COx emissions. In this work, for the first time, the possibility of promoting Ni-containing composite materials based on an organic matrix of polyvinyl alcohol (PVA) with MgO was demonstrated. The amount of MgO promoter varied from 1 to 10% by weight of Ni. The synthesized catalysts were characterized by the following methods: elemental analysis, TPR-H2, XRD, FTIR spectroscopy, Raman spectroscopy, SEM, TEM, SSA, and Raman fluorescence enhancement spectroscopy. The catalytic activity of the materials was tested in the pure CH4 decomposition reaction. Promotion with MgO contributes to an increase in the H2 yield per unit mass of Ni from 1.23 to 2.55 mol/gNi. The optimal content of the promoting component was 0.3% wt., which corresponded to 1% wt. from Ni. Carbon formed during CH4 decomposition in the form of nanotubes. The obtained carbon nanotubes (CNTs) were characterized by the following methods: XRD, Raman spectroscopy, SEM, and TEM. The length of the CNTs varies from 1 to 6 μm, the outer diameter ranges from 40 to 60 nm, and the inner diameter ranges from 10 to 20 nm.

Methane conversion for hydrogen production: technologies for a sustainable future

We review state-of-the-art technologies and processes of catalytic decomposition of methane (CDM) to produce hydrogen, a COx free technology with carbon nano materials (CNMs) as a byproduct, in view of the circular economy.

Balancing Act: Influence of Cu content in NiCu/C catalysts for methane decomposition

Thermal catalytic decomposition of methane is an innovative pathway to produce CO2-free hydrogen from natural gas. We investigated the role of Cu content in carbon-supported bimetallic NiCu catalysts. A graphitic...

Study on the mechanism of constructing structure defects on surface of activated carbon with carbon black to promote hydrogen production by thermal-decomposition of methane

Hydrogen production from catalytic decomposition of methane is a promising method of hydrogen production that caters to low-carbon energy sources. The low cost and easy regeneration of carbon-based catalysts is more compatible with the concept of sustainability than metal catalysts. The key problem with catalytic decomposition using activated carbon is the rapid deactivation of the activated carbon due to structural changes caused by the production and accumulation of deposited carbon. Carbon black, on the other hand, exhibits slowly increasing catalytic performance in the catalytic decomposition of methane. Therefore, combining the properties of the two, it is proposed to disperse and load the nano conductive carbon black onto the surface of urea-modified activated carbon, so that the activated carbon can also have self-repairing ability at a later stage. It is shown that the combined application of carbon black loading and urea modification enhances the structural properties of the activated carbon by enriching the microporous structure of the activated carbon surface, increasing the disorder of its crystal structure, and altering the content and concentration of oxygen-containing functional groups on the surface. These microstructural changes combined to enhance the overall catalytic activity of the activated carbon, including its late deactivation time and catalytic performance after deactivation.

Catalytic cracking of methane to hydrogen and carbon: Scale-up perspective

Decarbonizing natural gas for the production of H2 and value-added nanostructured graphitic carbons via catalytic decomposition of methane (CDM) presents an attractive alternative to conventional steam-methane reforming. This work is an attempt to establish the practical viability of the CDM process considering the reciprocity of methane conversion, the type and quantity of carbon formation, and the effective lifetime of the catalyst. Effects of the reaction parameters and reactor configurations on the catalyst performance, type of carbon-formation, and the catalyst degradation have been analyzed critically, providing state-of-the-art on laying a foundation for the development of new catalysts with better selectivity and longevity. Finally, a continuous regeneration-recycling system has been modeled by simulating a fluidized-bed reactor for Fe-based catalyst. The energy-exchange efficiency of regeneration/recirculation of catalyst via partial combustion has been established to lay out the guidelines for future development of the CDM process on a commercial-scale.

Optimization of methane catalytic decomposition in a fluidized bed reactor: A computational approach

Optimization of methane catalytic decomposition in a fluidized bed reactor: A computational approach

Effect of potassium in catalysts obtained by the solution combustion synthesis for co-production of hydrogen and carbon nanofibers by catalytic decomposition of methane

A set of catalysts containing 0.25–10 wt% K2O was prepared by solution combustion synthesis. The catalytic systems were characterized by X-ray diffraction, transmission electron microscopy, scanning electron microscopy, and low-temperature nitrogen adsorption. The catalytic methane decomposition was carried out at 0.5 MPa, 100 LCH4/(h·gcat), and temperature ranging from 550 to 750 °C. It has been found that varying the potassium content led to a change in the phase composition and textural characteristics of the resulting catalysts. The introduction of potassium (0.25 wt% K2O) into the nickel catalyst made it possible to change the particle size distribution towards the formation of smaller particles, from 5 to 30 nm to 5–10 nm, promoting the formation of higher yield of H2. The Ni-0.25 %K2O/Al2O3 и Ni-1 %K2O/Al2O3 catalysts demonstrated the highest hydrogen yield of 11.6 g/gcat and 17.0 g/gcat with a maximum at 675 and 750 °C, respectively. The highest yield of carbon material (51.0 g/gcat) was obtained over Ni-1 %K2O/Al2O3 catalyst.

Electrochemical splitting of methane in melts: Producing and tuning high-value carbon materials with controllable morphology

Catalytic decomposition of methane offers a viable solution for producing pure hydrogen and nanocarbon without emitting carbon dioxide. However, conventional thermal catalytic processes and catalysts have limitations in terms of poor carbon quality and catalyst deactivation due to carbon deposition. The newly developed electrochemical splitting of methane (ESM) in molten salt has emerged as a promising alternative that allows for the separate production of hydrogen at the anode and carbon deposition at the cathode. In this study, hydrogen produced via ESM while generating nanocarbon with diverse structures through manipulations of the cathode material and kinetics. Carbon nanotubes grown on Ni cathode, possessing high specific surface area and abundant functional groups, displayed excellent adsorptive capacity for dye adsorption. The open hollow nanocarbon grown on the Ag cathode displayed good capacitance performance. ESM technology has immense potential to enhance the utilization value of carbon by-products and the commercial production of green hydrogen.

Catalytic decomposition of methane for controllable production of carbon nanotubes and high purity H2 over LTA zeolite-derived Ni-based yolk-shell catalysts

Catalytic decomposition of methane for controllable production of carbon nanotubes and high purity H2 over LTA zeolite-derived Ni-based yolk-shell catalysts

Hierarchical Hollow Carbon Particles with Encapsulation of Carbon Nanotubes for High Performance Supercapacitors.

A novel and sustainable carbon-based material, referred to as hollow porous carbon particles encapsulating multi-wall carbon nanotubes (MWCNTs) (CNTs@HPC), is synthesized for use in supercapacitors. The synthesis process involves utilizing LTA zeolite as a rigid template and dopamine hydrochloride (DA) as the carbon source, along with catalytic decomposition of methane (CDM) to simultaneously produce MWCNTs and COx -free H2 . The findings reveal a distinctive hierarchical porous structure, comprising macropores, mesopores, and micropores, resulting in a total specific surface area (SSA) of 913 m2 g-1 . The optimal CNTs@HPC demonstrates a specific capacitance of 306 Fg-1 at a current density of 1 Ag-1 . Moreover, this material demonstrates an electric double-layer capacitor (EDLC) that surpasses conventional capabilities by exhibiting additional pseudocapacitance characteristics. These properties are attributed to redox reactions facilitated by the increased charge density resulting from the attraction of ions to nickel oxides, which is made possible by the material's enhanced hydrophilicity. The heightened hydrophilicity can be attributed to the presence of residual silicon-aluminum elements in CNTs@HPC, a direct outcome of the unique synthesis approach involving nickel phyllosilicate in CDM. As a result of this synthesis strategy, the material possesses excellent conductivity, enabling rapid transportation of electrolyte ions and delivering outstanding capacitive performance.

Kinetic study of Ni-M/CNT catalyst in methane decomposition under microwave irradiation

Methane catalytic decomposition has been studied with catalysts that can attenuate the energy of electromagnetic waves to heat and drive the reaction. Herein, we report, for the first time, a comprehensive kinetic study of Ni-M (M=Pd, Cu, or Fe)-CNT catalysts under microwave irradiation. These binary metal alloy nanoparticles have been synthesized on multiwalled carbon nanotube support with solvothermal process. These catalysts showed incredible performance for both absorbing microwave energy and catalyzing the reaction to form carbon nanotubes and hydrogen. Ni-M-CNT has a reaction order of 0.74. 10Ni-1 Pd-CNT, 10Ni-1Cu-CNT, and 10Ni-1Fe-CNT have activation energies at 87, 75, and 69 kJ/mol. The investigation was carried out in a differential reactor. The results indicated that 10Ni-1Fe-CNT had the lowest activation energy due to the increase in microwave susceptibility. This work pioneered the microwave catalytic methane decomposition field as well as paving the way for future electrification of COx-free hydrogen production.

Development of Ni–Mo carbide catalyst for production of syngas and CNTs by dry reforming of biogas

Biogas has been widely regarded as a promising source of renewable energy. Recently, the direct conversion of biogas over heterogeneous catalysts for the simultaneous production of syngas and carbon nanotubes exhibits a high potential for full utilization of biogas with great benefits. Involving the combined dry reforming of methane and catalytic decomposition of methane, the efficiency of process is strongly depended on the catalyst activity/stability, mainly caused by carbon deposition. In this study, Ni–Mo catalyst is engineered to provide a life-long performance and perform high activity in the combined process. The surface modification of catalysts by a controlled carburization pretreatment is proposed for the first time to produce a carbide catalyst along with improving the catalyst stability as well as the reactivity for direct conversion of biogas. The performance of as-prepared carbide catalysts is investigated with comparison to the oxide and metallic ones. As a result, the Ni–Mo2C catalyst exhibited superior activity and stability over its counterparts, even though the condensed nanocarbon was largely grown and covered on the surface. In addition, up to 82% of CH4 conversion and 93% of CO2 conversion could remain almost constant at 800 °C throughout the entire test period of 3 h under a high flowrate inlet stream of pure biogas at 48,000 cm3 g−1 h−1. The XPS spectra of catalysts confirmed that the presence of Mo2C species on the catalyst surface could promote the stability and reactivity of the catalyst, resulting in higher productivity of carbon nanotubes over a longer time.

Thermocatalytic Decomposition of Methane: A Review on Carbon-Based Catalysts.

The global initiatives on sustainable and green energy resources as well as large methane reserves have encouraged more research to convert methane to hydrogen. Catalytic decomposition of methane (CDM) is one optimistic route to generate clean hydrogen and value-added carbon without the emission of harmful greenhouse gases, typically known as blue hydrogen. This Review begins with an attempt to understand fundamentals of a CDM process in terms of thermodynamics and the prerequisite characteristics of the catalyst materials. In-depth understanding of rate-determining steps of the heterogeneous catalytic reaction taking place over the catalyst surfaces is crucial for the development of novel catalysts and process conditions for a successful CDM process. The design of state-of-the-art catalysts through both computational and experimental optimizations is the need of hour, as it largely governs the economy of the process. Recent mono- and bimetallic supported and unsupported materials used in CDM process have been highlighted and classified based on their performances under specific reaction conditions, with an understanding of their advantages and limitations. Metal oxides and zeolites have shown interesting performance as support materials for Fe- and Ni-based catalysts, especially in the presence of promoters, by developing strong metal-support interactions or by enhancing the carbon diffusion rates. Carbonaceous catalysts exhibit lower conversions without metal active species and largely result in the formation of amorphous carbon. However, the stability of carbon catalysts is better than that of metal oxides at higher temperatures, and the overall performance depends on the operating conditions, catalyst properties, and reactor configurations. Although efforts to summarize the state-of-art have been reported in literature, they lack systematic analysis on the development of stable and commercially appealing CDM technology. In this work, carbon catalysts are seen as promising futuristic pathways for sustained H2 production and high yields of value-added carbon nanomaterials. The influence of the carbon source, particle size, surface area, and active sites on the activity of carbon materials as catalysts and support templates has been demonstrated. Additionally, the catalyst deactivation process has been discussed, and different regeneration techniques have been evaluated. Recent studies on theoretical models towards better performance have been summarized, and future prospects for novel CDM catalyst development have been recommended.