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CC BY 4.0 · Pharmaceutical Fronts
DOI: 10.1055/a-2577-5738
Review Article

Research Progress on Continuous-Flow Nitrification Technology and Equipment

Zhipeng Zheng
1   Key Laboratory for Green Pharmaceutical Technologies and Related Equipment of Ministry of Education and Key Laboratory of Pharmaceutical Engineering of Zhejiang Province, Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou, People's Republic of China
,
Xiaobing Liang
1   Key Laboratory for Green Pharmaceutical Technologies and Related Equipment of Ministry of Education and Key Laboratory of Pharmaceutical Engineering of Zhejiang Province, Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou, People's Republic of China
,
Xiaorong Zhou
2   Zhejiang Ming Yi Chemical Machinery Co., Ltd., Qu Zhou, People's Republic of China
,
Rui Zhu
1   Key Laboratory for Green Pharmaceutical Technologies and Related Equipment of Ministry of Education and Key Laboratory of Pharmaceutical Engineering of Zhejiang Province, Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou, People's Republic of China
,
Fengfan Liu
1   Key Laboratory for Green Pharmaceutical Technologies and Related Equipment of Ministry of Education and Key Laboratory of Pharmaceutical Engineering of Zhejiang Province, Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou, People's Republic of China
3   Zhejiang Yangtze Delta Region Pharmaceutical Technology Research Park, Hu zhou, People's Republic of China
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Abstract

The mixture of concentrated nitric and sulfonic acids (mix acid) has been commonly used as a nitration reagent for the preparation of nitro compounds. Compared with the traditional batch reactor, continuous-flow nitrification technology has been recognized by the industry for its higher safety and production efficiency. As a frontier and hot topic in chemical engineering, continuous-flow reactor has gradually become an important platform for the development of new equipment, new processes, and new products for drug synthesis. Combining flow chemistry with real-time process analysis allows the study of reaction kinetics and the monitoring of the chemical synthesis process. In this work, the application of continuous-flow reaction technique in nitrification of aromatic rings, aromatic heterocycles, and aliphatic compounds is summarized. Based on process analysis technology and multistep series continuous-flow reaction to synthesize nitro compounds, the safe technology of nitrification reaction is realized in the green safety process.

Keywords

continuous-flow technology - nitration reaction - process analysis technique


Publication History

Received: 20 November 2024

Accepted: 08 April 2025

Article published online:
19 May 2025

© 2025. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution License, permitting unrestricted use, distribution, and reproduction so long as the original work is properly cited. (https://creativecommons.org/licenses/by/4.0/)

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