Preparation of Ni based mesoporous Al₂O₃ catalyst with enhanced CO₂ methanation performance

Area of Science:

• Catalysis
• Materials Science
• Chemical Engineering

Background:

• Developing efficient catalysts for carbon dioxide (CO2) methanation is crucial for mitigating greenhouse gas emissions and producing valuable methane (CH4).
• Traditional methods often rely on organic surfactants, posing environmental and cost concerns.
• Mesoporous materials offer high surface areas and tunable properties for catalytic applications.

Purpose of the Study:

• To synthesize a novel nickel-based mesoporous gamma-alumina (MA) catalyst using a surfactant-free partial hydrolysis method.
• To investigate the structural and catalytic properties of the prepared Ni/MA catalyst for CO2 methanation.
• To evaluate the catalyst's performance, stability, and selectivity in the CO2 methanation reaction.

Main Methods:

• Catalyst preparation via partial hydrolysis without organic surfactants.
• Characterization using N2 adsorption-desorption, H2-TPR, XRD, XPS, TG, SEM, and TEM-EDS.
• CO2 methanation reaction conducted in a fixed-bed reactor.

Main Results:

• The synthesized MA exhibited a high surface area and excellent hydrothermal stability.
• The MA support effectively dispersed nickel species, enhancing catalytic performance.
• Increased NiO incorporation led to more active metallic Ni sites, improving catalytic activity and CH4 selectivity.
• The fabric-like walls of the MA structure suppressed Ni aggregation and carbon deposition, boosting catalyst stability.

Conclusions:

• The surfactant-free Ni/MA catalyst demonstrates superior performance and stability for CO2 methanation.
• The mesoporous structure of MA plays a key role in promoting nickel dispersion and preventing deactivation.
• This approach offers a promising pathway for developing cost-effective and industrially applicable catalysts for CO2 utilization.