Process development for coproduction of hydrogen and chemicals in electrochemical reaction

• Project/Area Number: 18H01778
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 27020:Chemical reaction and process system engineering-related
• Research Institution: Kyoto University
• Principal Investigator: Kawase Motoaki 京都大学, 工学研究科, 教授 (60231271)
• Co-Investigator(Kenkyū-buntansha): 蘆田 隆一 京都大学, 工学研究科, 講師 (80402965)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Project Status: Completed (Fiscal Year 2020)
• Budget Amount: ¥17,420,000 (Direct Cost: ¥13,400,000、Indirect Cost: ¥4,020,000); Fiscal Year 2020: ¥4,810,000 (Direct Cost: ¥3,700,000、Indirect Cost: ¥1,110,000); Fiscal Year 2019: ¥5,980,000 (Direct Cost: ¥4,600,000、Indirect Cost: ¥1,380,000); Fiscal Year 2018: ¥6,630,000 (Direct Cost: ¥5,100,000、Indirect Cost: ¥1,530,000)
• Keywords: 電気化学反応 / 選択 / 水素 / 化成品 / 界面電位差

Outline of Final Research Achievements

Although electrochemical reactions are poor in energy efficiency which is limited by power generation efficiency, partial oxidation of alcohol in electrochemical reactions can be beneficial if the selectivity of the target product is greatly improved from conventional chemical processes. Partial oxidation of alcohol for producing aldehyde is an important organic reaction and it often has low aldehyde selectivity.
An electrochemical process was proposed for coproducing hydrogen and aldehyde from ethanol and water. It was demonstrated that the selectivity can be controlled by the interfacial potential difference. The highest aldehyde selectivity was observed at 0.8 V. The reactions rate was formulated with Tafel equation and the determined rate equations well reproduced the measured results.

Academic Significance and Societal Importance of the Research Achievements

カソードでの電解水素製造とアノードでの高選択性化成品製造を同時に行うプロセスを開発した。電気化学反応は高い選択性を有するため，従来プロセスよりも副生物が少なく，効率と環境負荷の点で優れた化成品製造プロセスの実現が期待できる。
また，電気化学反応の速度は，温度と濃度に加えて，電極と電解質の界面電位差にも依存するため，従来の化学工学にはない理論が必要である。速度論ならびに装置と運転条件の最適設計法を一般化し，将来の汎用的なプロセスの開発と新しい学理の構築の指針となった。

Research Products

• [Presentation] Development of a simultaneous production process of hydrogen and acetaldehyde by electrochemical reaction (2019)
  • Author(s): Keisuke Namura, Motoaki Kawase
  • Organizer: The 32nd International Symposium on Chemical Engineering
  • Int'l Joint Research
• [Presentation] 電気化学反応による水素とアセトアルデヒドの同時製造プロセスの開発 (2019)
  • Author(s): 名村 啓佑、綿野 夢大、河瀬 元明
  • Organizer: 化学工学会姫路大会2019
• [Presentation] 電気化学反応による水素とアセトアルデヒドの同時製造プロセスの開発 (2018)
  • Author(s): 名村啓佑
  • Organizer: 化学工学会 中国四国支部・関西支部合同徳島大会