CIESC Journal ›› 2023, Vol. 74 ›› Issue (4): 1570-1577.DOI: 10.11949/0438-1157.20221481

• Catalysis, kinetics and reactors • Previous Articles     Next Articles

Correlation with the redox V4+/V5+ ratio in VPO catalysts for oxidation of cyclohexane by NO2

Jian JIAN1(), Jiaming ZHANG2, Xiang SHE2, Hu ZHOU1, Kuiyi YOU2(), Hean LUO2()   

  1. 1.School of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Xiangtan 411201, Hunan, China
    2.School of Chemical Engineering, Xiangtan University, Xiangtan 411105, Hunan, China
  • Received:2022-11-14 Revised:2023-03-06 Online:2023-06-02 Published:2023-04-05
  • Contact: Kuiyi YOU, Hean LUO

V4+和V5+比例对钒磷氧催化NO2氧化环己烷性能的影响

蹇建1(), 张嘉明2, 佘祥2, 周虎1, 游奎一2(), 罗和安2()   

  1. 1.湖南科技大学化学化工学院,湖南 湘潭 411201
    2.湘潭大学化工学院,湖南 湘潭 411105
  • 通讯作者: 游奎一,罗和安
  • 作者简介:蹇建(1988—),男,博士,讲师,jianjianjqr@126.com
  • 基金资助:
    国家自然科学基金项目(22202068);湖南省自然科学基金项目(2021JJ30239);湖南省重点研发计划项目(2019GK2041)

Abstract:

Vanadium phosphorus oxide (VPO) catalysts doped with different transition metals were prepared by impregnation method, and their catalytic performance for cyclohexane oxidation by NO2 to adipic acid were tested. The XRD, XPS, H2-TPR and UV-Vis DRS were used to investigate the effect of transition metal doping on the valence structure of vanadium in VPO catalysts and the catalytic performance for oxidation of cyclohexane. The results showed that the introduction of transition metals could change the phase structure ratio of β-VOPO4 and (VO)2P2O7 in VPO samples, thus changing the ratio of V5+ and V4+. In addition, the valence structure of vanadium in VPO catalysts played an important effect in the oxidation of cyclohexane to adipic acid by NO2. The catalytic performance of M/AlVPO catalyst containing both V5+ and V4+ was significantly higher than that of the pure V5+ β-VOPO4 and pure V4+ (VO)2P2O7 catalysts. Among them, when Cu/AlVPO with V4+/V5+ of 0.52 was used as the catalyst, the conversion rate of cyclohexane was 65.4%, and the selectivity of adipic acid was 84.8% when Ni/AlVPO with V4+/V5+ of 0.66 was used as the catalyst.

Key words: VPO composite oxides, cyclohexane, adipic acid, catalytic oxidation, catalytic mechanism

摘要:

采用浸渍法制备不同钒价态结构的钒磷氧(VPO)复合氧化物催化剂,测试其对NO2氧化环己烷制备己二酸的催化性能,并采用XRD、XPS、H2-TPR和UV-Vis DRS等手段进行表征,考察不同过渡金属掺杂对VPO中钒价态结构的影响,以及催化氧化环己烷性能的影响。研究结果表明,过渡金属的引入能够改变VPO中β-VOPO4和(VO)2P2O7两种晶相结构,从而调变V5+ 和V4+ 的比例,且钒的价态比例对NO2氧化环己烷反应具有重要影响。同时含有V5+ 和V4+ 的M/AlVPO催化剂的催化性能明显高于纯V5+ 的β-VOPO4和纯V4+ 的(VO)2P2O7催化剂。其中,以V4+/V5+ 为0.52的Cu/AlVPO为催化剂时环己烷的转化率最高为65.4%,以V4+/V5+ 为0.66的Ni/AlVPO为催化剂时己二酸的选择性最高为84.8%。

关键词: 钒磷氧复合氧化物, 环己烷, 己二酸, 催化氧化, 催化机理

CLC Number: