Kolbe Electrolysis of Long‐Chain Fatty Acids for Efficient Production of Bio‐Based Hydrophobic Paraffin Waxes

Abstract

AbstractHerein, we present a comparative study on the Kolbe electrolysis of fatty acids. First, key parameters such as solvent composition and starting pH were briefly investigated with myristic acid (C14 : 0) as model fatty acid using a platinized titanium (Pt−Ti) anode involving the emerging liquid wax as environmentally friendly cosolvent. Second, the parameters were verified by experiments with fatty acids of different chain length (C10 : 0 to C18 : 0) which led to excellent results in the electrolysis of lauric acid (C12 : 0) with a current efficiency of 51±2 % after applying 1 FE. Comparable results (47±2 %) were obtained with a boron doped diamond anode (BDD). With current efficiencies of 45±1 % (Pt−Ti) and 46±1 % (BDD), the results were successfully transferred to an artificial fatty acid mixture as found in bio‐based coconut oil. Thus, a green and efficient method to produce bio‐based paraffin waxes on a multi‐gram scale was developed. The high hydrophobicity of the obtained waxes was validated by water contact angle measurements.