The techno-economics of the anodic peroxide evolution reaction

Abstract

The Oxygen Evolution Reaction (OER) is usually the go-to reaction for water-based electrolysis processes. However, this reaction can impede the performance and large-scale implementation of such processes due to its sluggish kinetics and the lack of value of its product stream. In order to boost the feasibility of electrochemical processes, research is being conducted on alternative anodic reactions. Even though thermodynamically less favorable, the peroxide evolution reaction yields an added-value product. In this study, the industrial relevance of the anodic peroxide evolution reaction was investigated. The aim of this thesis was to assess the potential for industrial application of this reaction. To do so, the electrochemical parameters of influence and the mechanisms behind the latter were investigated.
The evaluation of both economic and technical feasibility of the process was achieved by following three main threads. Firstly, a gross margin model was introduced. This model allowed to define performance targets of the electrolytic process based on viability requirements. Secondly, electrochemical experiments were carried out. Materials fit for large scale implementation were to be identified. Tin oxide- based materials (SnO2, Sn3O4, ITO and FTO) were investigated due to the stability of tin oxide in a large pH window. Carbon-based materials (CFP, PTFE-coated CFP and GDE) were investigated for their high current density responses and high peroxide yield. Once these materials were identified, systematic studies on electrolyte effects were carried out. Finally, product characterization methods were investigated in order to understand the role of ions such as HCO3 – and CO32– in the enhanced electrochemical production of peroxide.