Crude bioglycerol derived sulfur-doped carbon material for electrooxidation of bioglycerol and other alcohols

Abstract

By 2030, most developing countries aim to produce affordable and clean energy in accordance with UN Sustainable Development Goals. Thus, there has been a surge of interest in biofuels such as biodiesel. However, as the production of biodiesel increases, so does the issue of excess bioglycerol, which is a by-product of the process with no large-scale applications. To address this, the cost-effective utilization of bioglycerol, for example, in direct bioglycerol fuel cells or to synthesize carbon-based materials, is necessary. This study focuses on exploring the potential of used cooking oil to produce crude bioglycerol and further utilizing it as a carbon and energy source. Crude glycerol-based sulfur-doped carbon materials (S-CGBC) with graphene oxide-like appearance were synthesized using an acid dehydration method. The synthesized carbon material was fully characterized and was further analyzed to determine its potential as support materials on nickel foam for glycerol electrooxidation reaction (GEOR) and crude bioglycerol electrooxidation reaction (BGEOR). S-CGBC demonstrated good catalytic activity and stability for both GEOR and BGEOR, with high peak current densities of 262 mA/cm2 and 272 mA/cm2 at 0.6 V vs Ag/AgCl for GEOR and BGEOR, respectively. The HPLC analysis revealed 78.3% glycerol after 15 hours of bulk electrolysis of 1 M glycerol. The results of this study highlight the potential of waste crude bioglycerol as a good source of energy as well as of carbon materials.

Keywords

• Bioglycerol
• Sulfur-doped carbon materials
• Electrooxidation
• Ni foam
• HPLC