Liquid‐phase oxidation of p‐diethylbenzene (PDEB) to p‐ethylacetophenone (EAP) with hydrogen peroxide (H2O2) catalyzed by 5Co/SBA‐15 in a batch reactor and a fixed bed reactor was investigated. Based on the analysis of compositions, a reasonable reaction mechanism was discussed. Results show whether in a batch reactor or a fixed bed reactor, a mixture of EAP, 1‐(4‐ethylphenyl)‐1‐ethanol (EPEA), p‐diacetylbenzene (PDAB), 4‐acetylbenzoic acid (AA) and terephthalic acid (TA) could be detected. The reaction mechanism for oxidation of PDEB based on two reaction pathways for oxidizing ethyl group with H2O2 involving radical intermediates are proposed, PDEB firstly undergoes oxidation to give alkyl benzene carbocation and generates the key intermediate EPEA, which will be converted to EAP through pathway I. EAP can ultimately yield byproducts PDAB, AA and TA with pathway I and pathway II. Besides, diethyl group of PDEB can be tolerated pathway II to generate TA directly. The selectivity of EAP is steady around 68% in the fixed bed reactor, which is 16.52% higher than that in the batch reactor. It is essential to have a further study on the continuous flow process and obtain more data for industrial application.

A new cerium doped copper hybrid bimetallic organic framework (Ce/Cu-BTC) was synthesized for oxidizing p-diethylbenzene (PDEB) to p-ethylacetophenone (EAP) in the batch and fixed-bed reactors. The oxidization mechanism for PDEB to EAP over Ce/Cu-BTC was investigated. Results show Ce/Cu-BTC is a mischcrystal mixture of Ce-BTC and Cu-BTC, the addition of Ce can increase the crystal phase defects and enlarge the pore size of Cu-BTC. The conversion rate of PDEB is above 95 % and the yield of EAP are stable at 75 % in the Ce/Cu-BTC fixed bed reactor. A mixture of EAP, 1-(4-ethylphenyl)-1-ethanol (EPEA) and p-diacetylbenzene (PDAB) can be detected in the outlet of the reactor. The PDEB with Ce 4 + /Cu 2 + , H 2 O 2 and bromine free radical generate EPEA and EAP, the EAP is then further oxidized to PDAB. The mischcrystal structure of Ce/Cu-BTC is beneficial to improve the catalytic oxidation activity and reaction rate of PDEB to EAP.

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