Peroxodicarbonate: Electrosynthesis and first directions to green industrial applications
A new series of electrochemical microreactors with boron-doped diamond anodes has been designed at Fraunhofer IMM especially for the electrochemical production of peroxodicarbonate (PDC). Two models of ECMR, with and without integrated heat exchangers, were built and tested. The influence of several parameters was investigated and optimized conditions were created in this reactor design with two undivided cells. Using a saturated aqeuous solution of sodium carbonate at high current density (806 mA cm−2), the best electrosynthesis results of PDC (380 mM) performed on boron-doped diamond were achieved until today with excellent Faraday efficiency (76%). In some experiments, the progress of the reaction could be monitored inline by Raman spectroscopy (-O-O- 862.54 cm−1) and (CO3−2 1069.7 cm−1). Experiments performed to investigate the bleaching power of the peroxodicarbonate gave excellent results. Additionally, results of the temperature-dependent PDC degradation are generated. First results of the PDC used without activators as a brightening agent for waste paper, native wood and wood fibers are very promising.