【Ten Years of Great Progress in Chemical Technology】Industrialization of hydrogenation-ammonolysis process for producing malondiamine from 234 to 2023

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Ten years of rapid development in chemical engineering technology – praising the prosperity and strength of modern China. This is just a starting point; more participation will make things even more interesting. With you here, HaiChuan becomes even better. [Ten years of development in chemical engineering equipment] – continuous updates and summaries available; feel free to join the discussions at https://bbs.hcbbs.com/thread-3576046-1-1.html. Enhance quality awareness and promote high-quality development. ----------------------------------------- On September 1, 2023, the Xi’an Institute of Modern Chemistry learned that the complete set of technologies it developed for the production of malondiamine via hydroammoniation was successfully put into use at Yantai Wanhua Chengda Chemical Co., Ltd. on the first attempt. This marks the industrialization of China’s proprietary hydrogenation-amination technology for the synthesis of methylenediamine. A responsible official from the Xi’an Institute of Modern Chemistry explained that, compared with the traditional catalytic aminolysis process using 1,2-dichloropropane, this technology results in less emission of waste substances, making it more environmentally friendly ； It has lower toxicity, simpler steps, and higher selectivity compared to the acrylonitrile amination-reduction process. Since 2009, the fluorine-nitrogen chemical technology development team at Xi’an Institute of Modern Chemistry has been working on technical challenges, overcoming a series of difficulties such as the preparation of highly selective catalysts, the design of multiphase amination reactors, the separation of complex azeotic systems, and purification through distillation and crystallization. As a result, efficient catalysts with independent intellectual property rights, along with complete sets of industrialization technologies, have been developed, yielding a range of innovative achievements. At the beginning of this year, Yantai Wanhua Chengda Chemical Co., Ltd. completed the construction of an industrial facility for malondiamine, and by mid-August it passed a 72-hour operation test under conditions of \"full process, full capacity, and high quality\". During the evaluation period, the unit operated stably at 100% load, with all key performance indicators meeting or exceeding the design requirements. The product quality is satisfactory: the purity of the malondiamine product is 99.93%, while the purity of the by-product dimethylpiperazine crystals is 99.7%. The quality meets the standards of high-grade imported products. It is understood that methylenediamine, as a typical polyamine fine chemical, has a wide range of applications; it is mainly used in high-end polymers, pesticides, pharmaceuticals, synthetic dyes, and other fields. There is a shortage of this substance in the market, and China used to rely on imports for its supply. The domestic and international production processes mainly include the catalytic ammonolysis of 1,2-dichloropropane and the two-step reduction method using acrylonitrile, etc.; these processes suffer from issues such as high pollution, high energy consumption, equipment corrosion, and high toxicity.