Boosting Dimethyl Carbonate Production from CO₂ and Methanol using Ceria-Ionic Liquid Catalyst

Area of Science:

• Green Chemistry
• Catalysis
• Materials Science

Background:

• The chemical industry seeks sustainable routes for producing bulk chemicals.
• Direct synthesis of dimethyl carbonate (DMC) from carbon dioxide (CO₂) and methanol (MeOH) is a key goal for a sustainable chemical industry.
• Existing methods often require stoichiometric dehydrating agents, posing environmental concerns.

Purpose of the Study:

• To develop a novel, stable catalyst for the direct synthesis of DMC from CO₂ and MeOH.
• To investigate the catalytic performance and stability of a CeO₂ nanoparticle and ionic liquid composite.
• To explore the synergistic effects between CeO₂ and the ionic liquid for enhanced catalytic activity.

Main Methods:

• Synthesis of CeO₂ nanoparticles modified with 1-butyl-3-methylimidazolium hydrogen carbonate ([BMIm][HCO₃]).
• Catalytic testing for DMC synthesis under varying conditions (5 MPa CO₂, 130°C).
• Characterization using XRD, XPS, TPD, Raman, TGA, FTIR, SEM, and TEM to understand catalytic mechanisms.

Main Results:

• The CeO₂@[BMIm][HCO₃] catalyst achieved a 10.4% DMC yield and 16.1% methanol conversion.
• The catalyst demonstrated high thermal stability and recyclability with no significant loss in performance.
• Characterization revealed synergistic effects between CeO₂ and [BMIm][HCO₃], attributed to increased surface oxygen vacancies.

Conclusions:

• The CeO₂@[BMIm][HCO₃] catalyst offers an efficient and stable platform for sustainable DMC production.
• The nanoparticle@ionic liquid composite effectively merges the properties of its components for enhanced catalysis.
• This approach presents an attractive route for producing valuable chemicals from renewable resources.