SCI和EI收录∣中国化工学会会刊

Chinese Journal of Chemical Engineering ›› 2018, Vol. 26 ›› Issue (10): 2169-2175.DOI: 10.1016/j.cjche.2018.04.018

• Energy, Resources and Environmental Technology • 上一篇    下一篇

Reliable, environmentally friendly method for the recycling of spent Ag/α-Al2O3 catalysts using (NH4)2Ce(NO3)6

Xulong Dong1,2,3, Jian Li1,2,3, Qinggui Xiao2,3, Hui Zhang2,3, Tao Qi2,3   

  1. 1 University of Chinese Academy of Sciences, Beijing 100049, China;
    2 National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology, Institute of Process, Chinese Academy of Sciences, Beijing 100190, China;
    3 Key Laboratory of Green Process and Engineering, Institute of Process, Chinese Academy of Sciences, Beijing 100190, China
  • 收稿日期:2017-12-29 修回日期:2018-04-07 出版日期:2018-10-28 发布日期:2018-11-14
  • 通讯作者: Hui Zhang,E-mail addresses:zhanghv@ipe.ac.cn;Tao Qi,E-mail addresses:tqgreen@home.ipe.ac.cn
  • 基金资助:

    Supported by the Key Research Program of Frontier Sciences of CAS (QYZDJ-SSWJSC021), the Science and Technology Cooperation for Yunnan Provinces and CAS (2016IB002), Science and Technology Service Network Initiative of CAS (KFJ-SW-STS-148), and National Natural Science Foundation of China (21506233, 51402303, 21606241, 51374191).

Reliable, environmentally friendly method for the recycling of spent Ag/α-Al2O3 catalysts using (NH4)2Ce(NO3)6

Xulong Dong1,2,3, Jian Li1,2,3, Qinggui Xiao2,3, Hui Zhang2,3, Tao Qi2,3   

  1. 1 University of Chinese Academy of Sciences, Beijing 100049, China;
    2 National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology, Institute of Process, Chinese Academy of Sciences, Beijing 100190, China;
    3 Key Laboratory of Green Process and Engineering, Institute of Process, Chinese Academy of Sciences, Beijing 100190, China
  • Received:2017-12-29 Revised:2018-04-07 Online:2018-10-28 Published:2018-11-14
  • Contact: Hui Zhang,E-mail addresses:zhanghv@ipe.ac.cn;Tao Qi,E-mail addresses:tqgreen@home.ipe.ac.cn
  • Supported by:

    Supported by the Key Research Program of Frontier Sciences of CAS (QYZDJ-SSWJSC021), the Science and Technology Cooperation for Yunnan Provinces and CAS (2016IB002), Science and Technology Service Network Initiative of CAS (KFJ-SW-STS-148), and National Natural Science Foundation of China (21506233, 51402303, 21606241, 51374191).

摘要: Traditionally, Ag-containing solid wastes are leached by nitric acid in order to recycle the noble metal. However, the huge amounts of emission of toxic nitrogen oxides demand the development of a new method for silver recycling. Recently, considering the Ce(IV) solution could be regenerated with electrolyzation method, our group invented a novel environmentally friendly process by using Ce(IV) as the oxidant to dissolve silver from the spent Ag/α-Al2O3 catalysts without NOx emission. To find out the optimal parameters, in this work, the leaching reaction was thoroughly investigated with respect to the temperature, oxidant and HNO3 concentrations, stirring speed, and time. The optimized leaching reaction gave the leaching silver rate 99.8% in 1 h. The kinetic plots suggested a shrinking core model with the internal diffusion-controlled process and the activation energy of 38.83 kJ·mol-1. The order in which the experimental conditions influence the reaction was determined through orthogonal analysis:temperature > oxidant concentration > HNO3 concentration > stirring speed.

关键词: Cerium ammonium nitrate (CAN), Silver, Spent catalyst, Leaching, Kinetics

Abstract: Traditionally, Ag-containing solid wastes are leached by nitric acid in order to recycle the noble metal. However, the huge amounts of emission of toxic nitrogen oxides demand the development of a new method for silver recycling. Recently, considering the Ce(IV) solution could be regenerated with electrolyzation method, our group invented a novel environmentally friendly process by using Ce(IV) as the oxidant to dissolve silver from the spent Ag/α-Al2O3 catalysts without NOx emission. To find out the optimal parameters, in this work, the leaching reaction was thoroughly investigated with respect to the temperature, oxidant and HNO3 concentrations, stirring speed, and time. The optimized leaching reaction gave the leaching silver rate 99.8% in 1 h. The kinetic plots suggested a shrinking core model with the internal diffusion-controlled process and the activation energy of 38.83 kJ·mol-1. The order in which the experimental conditions influence the reaction was determined through orthogonal analysis:temperature > oxidant concentration > HNO3 concentration > stirring speed.

Key words: Cerium ammonium nitrate (CAN), Silver, Spent catalyst, Leaching, Kinetics