Hydroxyacetone: A Glycerol-Based Platform for Electrocatalytic Hydrogenation and Hydrodeoxygenation Processes

Area of Science:

• Electrochemistry
• Catalysis
• Green Chemistry

Background:

• Glycerol, a byproduct of biodiesel production, can be dehydrated to hydroxyacetone.
• Hydroxyacetone serves as a valuable platform chemical for synthesizing various organic compounds.
• Electrocatalytic methods offer sustainable routes for chemical synthesis, reducing waste and energy consumption.

Purpose of the Study:

• To investigate the electrocatalytic synthesis of acetone, 1,2-propanediol, and 2-propanol from hydroxyacetone.
• To evaluate non-noble metal electrodes and electrolyte compositions for optimal product selectivity, Coulombic efficiency (CE), and reaction rates.
• To explore the electrocatalytic hydrogenation and hydrodeoxygenation pathways of hydroxyacetone.

Main Methods:

• Screening of 11 non-noble metal electrodes.
• Testing of three different electrolyte compositions.
• Electrochemical analysis of selectivity, Coulombic efficiency (CE), and reaction rates for hydroxyacetone conversion.

Main Results:

• Iron electrodes in a chloride electrolyte demonstrated high selectivity (84.5%) and reaction rates (782 mmol h⁻¹ m⁻²) for 1,2-propanediol formation at 0.09 M hydroxyacetone.
• Increasing hydroxyacetone concentration to 0.5 M significantly enhanced performance, yielding a reaction rate of 2248.1 mmol h⁻¹ m⁻² and a CE of 64.5%.
• Copper and lead electrodes showed optimal acetone formation in chloride solutions, with lead exhibiting minimal side product formation. 2-propanol was synthesized via consecutive acetone oxidation.

Conclusions:

• Hydroxyacetone is a viable platform for electrocatalytic synthesis of valuable chemicals.
• Iron electrodes in chloride electrolytes are highly effective for producing 1,2-propanediol.
• Non-noble metal electrocatalysis provides a sustainable and efficient route for producing acetone and propanols from hydroxyacetone.