Publication Details

Category Text Publication
Reference Category Journals
DOI 10.1016/j.cej.2026.176358
Licence creative commons licence
Title (Primary) Experimental optimization and process modelling of the selective electrochemical hydrogenation of phenol to cyclohexanol using a non-noble metal catalyst
Author Saeidi, N.; Chávez Morejón, M.; Harnisch, F. ORCID logo
Source Titel Chemical Engineering Journal
Year 2026
Department MIBITECH; TECH
Volume 537
Page From art. 176358
Language englisch
Topic T7 Bioeconomy
Supplements Supplement 1
Keywords Phenol; Electrochemical hydrogenation; Non-noble metal catalyst; Electroorganic synthesis; Process modelling
Abstract Electrochemical hydrogenation (ECH) enables upgrading aqueous phenolic streams to cyclohexanol at room temperature and ambient pressure without the need for external hydrogen and noble metal catalysts. Screening of non-noble materials (Ni-, Fe-, and Cu-based) using a Na2SO4 electrolyte identified Raney nickel (RNi) as the sole catalyst achieving selectivity to cyclohexanol (Scyclohexanol) as the only detected liquid-phase product. A catalyst-free control showed no measurable product formation, supporting that electrogenerated hydrogen is utilized via heterogeneous hydrogenation on suspended RNi. It was observed that hydrogen availability was not limiting in the potential range of −1.2 to −1.9 V vs. Ag/AgCl, but increasing catalyst loading only modestly increases cyclohexanol formation. In contrast, the operating conditions are decisive. Lowering pH and decreasing Na2SO4 concentration markedly increase Coulombic efficiency (CE) and cyclohexanol yield (Ycyclohexanol), reaching CE = 43.9% and Ycyclohexanol = 22% in 1 mM Na2SO4 after 24 h with >90% carbon balance and an energy demand of 3.6 kWh mol−1 cyclohexanol. Kinetic analysis yields apparent first-order kinetics of phenol conversion (k_app = 0.0164 h−1, R2 = 0.984). A fed-batch flowsheet model coupling a water electrolyser to the ECH reactor was validated against the experimental concentration–time profiles. The model identifies electrolyser capacity (i.e., H2 generation rate) as the primary lever for increasing throughput at fixed current-density constraints, rather than a limitation of intrinsic reaction selectivity.
Saeidi, N., Chávez Morejón, M., Harnisch, F. (2026):
Experimental optimization and process modelling of the selective electrochemical hydrogenation of phenol to cyclohexanol using a non-noble metal catalyst
Chem. Eng. J. 537 , art. 176358
10.1016/j.cej.2026.176358