Division Chemistry - Sustainable Chemical Syntheses, Fraunhofer Institute for Microengineering and Microsystems IMM, Carl-Zeiss-Straße 18-20, 55129, Mainz, Germany.
Technical University of Darmstadt, Department of Chemistry, Ernst-Berl-Institut für Technische und Makromolekulare Chemie, Aalrich-Weiss-Straße 8, 64287, Darmstadt, Germany.
ChemistryOpen. 2022 Oct;11(10):e202200171. doi: 10.1002/open.202200171.
The Kolbe electrolysis is a promising reaction to combine the usage of electrons as reagents and the application of renewable generated carboxylic acids as raw materials producing value added chemicals. Within this study, the electrolysis was conducted in a specially developed concept electrochemical microreactor and draws the particular attention to continuous operation and reuse of the aqueous electrolyte as well as of the dissolved unreacted feedstock. The electrolysis was conducted in alkaline aqueous solution using n-octanoic acid as model substance. Platinized titanium as anode material in an undivided cell setup was shown to give Kolbe selectivity above 90 %. During the technically relevant conditions of current densities up to 0.6 A cm and overall electrolysis times of up to 3 h, a high electrode stability was observed. Finally, a proof-of-concept continuous operation and the numbering up potential of the ECMR could be demonstrated.
科尔贝电解是一种很有前途的反应，可以将电子作为试剂使用，并利用可再生生成的羧酸作为原料来生产增值化学品。在这项研究中，电解是在专门开发的电化学微反应器概念中进行的，特别关注水相电解质以及未反应的溶解原料的连续操作和再利用。电解在碱性水溶液中进行，以正辛酸作为模型物质。在未分隔的电池装置中，使用镀铂钛作为阳极材料，其科尔贝选择性超过 90%。在电流密度高达 0.6 A/cm 和总电解时间长达 3 小时的技术相关条件下，观察到高电极稳定性。最后，证明了 ECMR 的连续操作和扩大规模的潜力。
