Electrochemical Oxidation of 5-Hydroxymthylfurfural Using the Supported Ionic Liquid Phase Approach

The search for renewable instead of fossil resources gained attention in recent years, and sustainability and future-oriented aspects are paramount for chemical processes to replace finite fossil resources. To render chemistry more sustainable, there are two possibilities, which attract attention right now: 1) Waste streams and energy leakages are minimized or even diminished by closing material and energy loops. 2) Sustainable grown biomass as environmentally friendly feedstock, thus utilizing natural materials cycle. Regarding production, use of bio-based feedstock platform chemicals plays a major role, such as e.g. 5 Hydroxymethylfurfural (HMF) and its oxidation product 2,5-Furandicarboxylic acid (FDCA). HMF itself can be derived from biomass (e.g. C5/C6 sugars), which is considered a sustainable feedstock. FDCA on the other hand can substitute terephthalic acid, which is produced from crude oil and is primarily used as a precursor for polyethylene terephthalate (PET) that has an annual production of over 50 million tonnes. So HMF oxidation features one of the most interesting synthesis routes involving a biomass based platform chemical and leading to a highly requested substitute for the polymer sector. Using anodic HMF oxidation in water based electrolyte to yield FDCA opens the opportunity to generate hydrogen (H2) as the cathodic product. H2 itself is suited to overcome issues like sustainability, environmental emissions and energy security in a possible hydrogen economy. Furthermore, it can be integrated in already existing energy and transport systems, while decarbonizing them at the same time as air pollution can be reduced this way. It can be utilized in a broad variety of promising future oriented applications like power to power, power to gas, hydrogen refueling and stationary fuel cell. Demand of hydrogen is around 70 million tons per year (2018), while its production is accountable for over 800 million tons of CO2 per year, which elevates electrolysis into a possible way to create hydrogen more sustainable. Therefore, researching a suitable electrode and/or catalyst for electrochemical HMF oxidation attracted a lot of attention in recent years as it is the key for high energy and feedstock efficiency