Oxidation of benzene to phenol with N_(2)O over a hierarchical Fe/ZSM-5 catalyst  

作　　者：Cui Ouyang Jianwei Li Yaqi Qu Song Hong Songbo He 

机构地区：[1]State Key Laboratory of Chemical Resource Engineering,Beijing University of Chemical Technology,Beijing,100029,China [2]Green Chemical Reaction Engineering,Engineering and Technology Institute Groningen,University of Groningen,Nijenborgh 4,Groningen,9747 AG,the Netherlands [3]CoRe Pro,Colijnlaan 21,Groningen,9722 PJ,the Netherlands

出　　处：《Green Energy & Environment》2023年第4期1161-1173,共13页绿色能源与环境（英文版）

基　　金：Financial support by the Specialized Research Fund for Doctoral Program of Higher Education,China (No.20120010110003)。

摘　　要：Catalytic oxidation of benzene with N_(2)O to phenol over the hierarchical and microporous Fe/ZSM-5-based catalysts in a continuous fixedbed reactor was investigated.The spent catalyst was in-situ regenerated by an oxidative treatment using N_(2)O and in total 10 reaction-regeneration cycles were performed.A 100% N_(2)O conversion,93.3% phenol selectivity,and high initial phenol formation rate of 16.49±0.06mmol_(phenol gcatalyst)^(-1)h^(-1)at time on stream(TOS) of 5 min,and a good phenol productivity of 147.06 mmol_(phenol gcatalyst)^(-1)during catalyst lifetime of 1800 min were obtained on a fresh hierarchical Fe/ZSM-5-Hi2.8 catalyst.With the reaction-regeneration cycle,N_(2)O conversion is fully recovered within TOS of 3 h,moreover,the phenol productivity was decreased ca.2.2±0.8% after each cycle,leading to a total phenol productivity of ca.0.44 ton_(pheol kg_(catalyst)^(-1)estimated for 300 cycles.Catalyst characterizations imply that the coke is rapidly deposited on catalyst surface in the initial TOS of 3 h(0.28 mgc_(gcatalyst)^(-1)min^(-1)) and gradually becomes graphitic during the TOS of 30 h with a slow formation rate of 0.06 mgc g_(catalyst)^(-1)min^(-1).Among others(e.g.,the decrease of textural property and acidity),the nearly complete coverage of the active Fe-O-Al sites by coke accounts for the main catalyst deactivation.Besides these reversible deactivation characteristics related to coking,the irreversible catalyst deactivation is also observed with the reaction-regeneration cycle.The latter is reflected by a further decreased amount of the active Fe-O-Al sites,which agglomerate on catalyst surface with the cycle,likely associated with the hard coke residue that is not completely removed by the regeneration.

关 键 词：Hierarchical Fe/ZSM-5 N_(2)O conversion Phenol product productivity Reaction-regeneration cycles Irreversible deactivation mechanism 

分 类 号：TQ426[化学工程] TQ243.12[环境科学与工程—环境工程] X701