Upgrading of Ethanol to 1,1-Diethoxyethane by Proton-Exchange Membrane Electrolysis

The direct acetalization of ethanol is a significant challenge for upgrading bioethanol to value-added chemicals. In this study, 1,1-diethoxyethane (DEE) is selectively synthesized by the electrolysis of ethanol using a proton-exchange membrane (PEM) reactor. In the PEM reactor, a Pt/C catalyst promoted the electro-oxidation of ethanol to acetaldehyde. The Nafion membrane used as the PEM served as a solid acid catalyst for the acetalization of ethanol and electrochemically formed acetaldehyde. DEE was obtained at high faradaic efficiency (78 %) through sequential electrochemical and nonelectrochemical reactions. The DEE formation rate through PEM electrolysis was higher than that of reported systems. At the cathode, protons extracted from ethanol were reduced to H-2. The electrochemical approach can be utilized as a sustainable process for upgrading bioethanol to chemicals because it can use renewable electricity and does not require chemical reagents (e. g., oxidants and electrolytes).

Automated summary

In this study, 1,1-diethoxyethane (DEE) was selectively synthesized by the electrolysis of ethanol using a proton-exchange membrane (PEM) reactor, achieving the direct acetalization of ethanol. High faradaic efficiency of DEE was obtained through sequential electrochemical and nonelectrochemical reactions without the need for chemical reagents. This electrochemical approach provides a sustainable process for upgrading bioethanol to chemicals by utilizing renewable electricity.