催化学报 ›› 2023, Vol. 54: 238-249.DOI: 10.1016/S1872-2067(23)64541-3

• 论文 • 上一篇    下一篇

磁性可循环高熵金属氧化物催化剂用于活化氧气催化氧化脱硫

吴沛文a,b, 邓畅a, 刘锋c, 朱昊男a, 陈琳琳a, 刘若禹a, 朱文帅a,b,*(), 徐春明b   

  1. a江苏大学化学化工学院, 江苏镇江212013
    b中国石油大学(北京)化学工程与环境学院, 重质油全国重点实验室, 北京102249
    c中国石油化工股份有限公司石油化工科学研究院, 北京100083
  • 收稿日期:2023-08-17 接受日期:2023-10-12 出版日期:2023-11-18 发布日期:2023-11-15
  • 通讯作者: *电子信箱: zhuws@cup.edu.cn (朱文帅).
  • 基金资助:
    国家重点研发计划(2022YFA1504404);国家重点研发计划(2022YFA1504403);国家自然科学基金(22178154);国家自然科学基金(22008094)

Magnetically recyclable high-entropy metal oxide catalyst for aerobic catalytic oxidative desulfurization

Peiwen Wua,b, Chang Denga, Feng Liuc, Haonan Zhua, Linlin Chena, Ruoyu Liua, Wenshuai Zhua,b,*(), Chunming Xub   

  1. aSchool of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013, Jiangsu, China
    bCollege of Chemical Engineering and Environment, State Key Laboratory of Heavy Oil Processing, China University of Petroleum-Beijing, Beijing 102249, China
    cSINOPEC Research Institute of Petroleum Processing Co. Ltd, Beijing 100083, China
  • Received:2023-08-17 Accepted:2023-10-12 Online:2023-11-18 Published:2023-11-15
  • Contact: *E-mail: zhuws@cup.edu.cn (W. Zhu).
  • Supported by:
    National Key R&D Program of China(2022YFA1504404);National Key R&D Program of China(2022YFA1504403);National Natural Science Foundation of China(22178154);National Natural Science Foundation of China(22008094)

摘要:

燃油中的含硫化合物燃烧会导致酸雨、雾霾等环境问题, 因此需要降低燃油中硫化物浓度. 但是, 目前工业上采用的加氢脱硫(HDS)技术在脱除芳香硫化物时需要更高的温度、压力和氢耗, 不利于碳减排(生产1吨H2排放10-20吨CO2), 因此亟需开发非HDS工艺. 在各种非HDS技术中, 以O2为氧化剂的氧化脱硫(ODS)技术由于具有对芳香族硫化物脱除性能高、成本低、反应条件温和等优点, 而受到广泛关注. 在ODS过程中, 催化剂的设计是关键之一. 研究发现, 金属氧化物具有较好的活化O2性能, 但是传统金属氧化物存在活性位点有限、分离回收较难等不足. 近年来, 人们发现, 高熵金属氧化物在以O2为氧化剂的催化氧化反应中表现出较好的催化性能, 但如何进一步提升其循环使用性能, 是目前高熵金属氧化物在ODS中应用所面临的挑战.

为解决上述问题, 本文通过组分设计在高熵金属氧化物催化剂中引入高催化活性组分和磁性元素, 再采用机械化学球磨辅助高温煅烧策略, 构筑了一类新型磁性高熵金属氧化物催化剂(CoCrFeMnNiOx, HEMO), 并用于活化O2催化氧化脱除燃油中芳香族硫化物. 实验发现, 900 oC煅烧制得的HEMO-900催化剂性能最优. 催化剂的结构表征结果表明, 通过球磨辅助策略能够降低高熵结构的形成温度. 进一步研究表明, 高熵结构不仅能够提升催化活性组分的分散度, 而且有助于活性组分的电荷调控, 从而显著增强了HEMO-900对O2分子的活化能力. 将所制备的HEMO-900催化剂用于以O2为氧化剂的燃油氧化脱硫体系中, 能够获得较好的脱硫性能, 在最优条件下能够获得96.9%的脱硫率(硫化物浓度降低至0.001%以下). 此外, HEMO-900催化剂能够高效氧化脱除燃油中不同种类芳香族硫化合物, 拓宽了其在不同类型燃油深度脱硫中的应用. 进一步分析发现, HEMO-900催化剂可以将燃油中二苯并噻吩定向氧化为二苯并噻吩砜. 同时, HEMO-900催化剂对真实油品中的硫化物也表现出较好的脱除性能. 此外, HEMO-900催化剂还有较好的磁性循环使用性能: 通过外加磁场, 可以快速将HEMO-900催化剂与燃油相分离, 该性能使得催化剂能够在连续反应过程中被高效回收和重复利用. 本研究中, HEMO-900催化剂在5次循环使用后, 其ODS活性仍达到91.1%.

综上所述, 本文通过机械化学球磨辅助高温煅烧法成功合成了一种可磁性回收的高熵金属氧化物催化剂, 实验发现了机械球磨辅助能够显著降低高熵结构的形成温度. 设计制得的催化剂兼具较好的活化O2催化燃油氧化脱硫性能和可磁性分离回收的特点. 通过设计该类可磁性分离的高熵金属氧化物催化剂, 不仅为实现温和条件下燃油深度脱硫提供新的选择, 而且为其他多相催化氧化反应催化剂设计提供了新思路.

关键词: 高熵, 过渡金属氧化物, 磁性分离, 催化氧化, 脱硫

Abstract:

High-entropy metal oxide catalysts have demonstrated exceptional performance in activating oxygen for catalytic oxidation reactions. However, ensuring their ease of cyclic usage is crucial to broadening their applications. To address this challenge, a magnetic and recyclable high-entropy metal oxide catalyst is designed and its potential in catalytic oxidative desulfurization of fuel oils with oxygen as the oxidant is also investigated. Through a mechanochemical-assisted calcination method, the magnetic high-entropy metal oxide catalyst (HEMO-900) is successfully synthesized, and the structure of the HEMO-900 catalyst is comprehensively characterized. In addition, it is found that the high-entropy structure facilitates charge modulation of the active components, thereby enhancing the oxygen activation performance. The HEMO-900 catalyst exhibits exceptional oxygen activation ability and catalytic oxidative desulfurization performance, and 96.9% of sulfur removal is achieved under optimal conditions. In addition, it achieves profound desulfurization of various fuel samples by efficiently oxidizing and eliminating diverse aromatic sulfur compounds. Additionally, the catalyst demonstrates outstanding magnetically recyclable properties, enabling rapid separation and recovery from the fuel oil phase through the application of an external magnetic field, making the HEMO-900 catalyst maintained a remarkable sulfur removal efficiency of 91.1% even in the 5th cycle. Therefore, this magnetically recyclable HEMO-900 catalyst possesses significantly promising research and application prospects in the field of catalytic oxidative desulfurization of fuel oils with oxygen as the oxidant, as well as some other heterogeneous catalysis.

Key words: High entropy, Transition metal oxide, Magnetic separation, Catalytic oxidation, Desulfurization