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陈鑫超1 凌晨1 蒋新1 陈帅帅1 卢建刚2

(1.浙江大学化学工程与生物工程学院浙江省化工高效制造技术重点实验室, 浙江杭州 310027)
(2.浙江大学控制科学与工程学院工业控制技术国家重点实验室, 浙江杭州 310027)

【摘要】探索了利用扩散反应的耦合制备更均匀的铜锌共沉淀物的方法。通过在微反应器中引入水层并调节水层占总流量的比例, 制得了高催化活性的Cu/Zn O共沉淀催化剂。采用高倍电镜线扫 (HRTEM/EDS) 、X射线衍射 (XRD) 、热重分析 (TG) 、氢气程序升温还原 (H2-TPR) 、N2O化学反应法分析催化剂微结构的差异以及演变关系。结果显示, 水层占比增加, 初始沉淀物Cu-Zn分布更加均匀, 陈化得到的前体中锌含量增大, 焙烧得到的氧化物CuO和Zn O接触面积增加, 相互作用力不断增强, 最终提升了催化剂催化活性。通过模型数值分析发现, Zn2+较快的扩散速率部分抵消了其反应速率慢导致的不均匀性;随着水层占比增加, 形成均匀沉淀的扩散-反应动态平衡区域增加, 产物中均匀沉淀物的比例得以提高。

【关键词】 微反应器;共沉淀法;显微结构;模型;数值模拟;Cu-Zn分布;扩散-反应平衡;


【基金资助】 国家重点研发计划项目 (2017YFC0211802) ; 国家自然科学基金项目 (21276223, 21676236) ;

Effect of water layer on Cu-Zn co-precipitation in microreactor

CHEN Xinchao1 LING Chen1 JIANG Xin1 CHEN Shuaishuai1 LU Jiangang2

(1.Zhejiang Provincial Key Laboratory of Advanced Chemical Engineering Manufacture Technology, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, Zhejiang, China 310027)
(2.State Key Laboratory of Industrial Control Technology, Department of Control Science and Engineering, Zhejiang University, Hangzhou, Zhejiang, China 310027)

【Abstract】A method aiming to prepare more uniform Cu-Zn co-precipitate by coupling of diffusion and reaction process was probed in this article and Cu/ZnO co-precipitated catalysts with high catalytic activity were prepared by introducing water layer into the microreactor and adjusting the ratio of water layer to the total flow. The microstructures and evolution process of the catalysts were analyzed by HRTEM/EDS, X-ray diffraction (XRD), thermogravimetric analysis (TG), hydrogen temperature-programmed reduction (H2-TPR), and N2O chemical reaction methods. The results show that as the proportion of water layer increases, the Cu-Zn distribution of the initial precipitate is more uniform; zinc content in the precursor obtained by the aging is increased; the contact area of the oxides CuO and ZnO is increased; and the interaction force is continuously enhanced. Therefore, larger contact area between calcined oxides CuO and ZnO was achieved, leading to better dispersibility and stronger interaction, with the final catalytic activity of the catalyst significantly enhanced. Numerical analysis based on the model established by MATLAB revealed that the uniformity caused by slower reaction rate of Zn2+ can be neutralized by faster diffusion rate of its own. The diffusion–reaction equilibrium region, defined as capable to obtain uniform precipitate, was enlarged with the increasing ratio of water layer and larger proportion of uniform precipitate was achieved simultaneously.

【Keywords】 microreactor; co-precipitation; microstructure; model; numerical simulation; Cu-Zn distribution; diffusion–reaction equilibrium;


【Funds】 National Key Research and Development Program of China (2017YFC0211802) ; National Natural Science Foundation of China (21276223, 21676236) ;

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This Article


CN: 11-1946/TQ

Vol 69, No. 10, Pages 4261-4268

October 2018


Article Outline


  • Introduction
  • 1 Experimental materials and methods
  • 2 Results and discussion
  • 3 Conclusions
  • References