Methane Bubbled Through Seawater Can be Converted to Methanol With High Efficiency

Area of Science:

• Electrochemistry
• Catalysis
• Environmental Science

Background:

• Partial oxidation of methane (POM) is crucial for converting methane into valuable chemicals.
• Traditional POM methods often face challenges with selectivity and efficiency.
• Methane's low solubility in water limits reaction efficiency in aqueous systems.

Purpose of the Study:

• To develop an efficient and selective method for partial oxidation of methane (POM) to methanol.
• To investigate the use of air-methane microbubbles in saltwater under an alternating electric field.
• To explore the synergistic effects of electrochemistry and microbubble dispersion on methane conversion.

Main Methods:

• Formation of air-methane microbubbles (20-40 µm) in 3% NaCl or KCl saltwater.
• Application of an alternating electric field (100 mV) using a copper oxide foam electrode.
• Control of POM process pathways and extent by tuning electric field frequency and amplitude.

Main Results:

• Achieved over 90% selectivity for methanol formation from methane.
• Demonstrated synergistic POM processes driven by Cl- and O2- radical generation.
• Estimated methane to methanol conversion yield of 57% at a rate of 887 µM h-1.

Conclusions:

• The microbubble-enhanced electrochemical method offers precise control over POM.
• This technique shows promise for atmospheric methane removal using seawater.
• Potential for converting concentrated methane sources into value-added methanol.