After the company’s 50 KMT/year adiponitrile project was smoothly put into operation at Huafon’s Chongqing plant, another 50 KMT/year adiponitrile facility was put into trial production this year. The Phase II 100 KMT/year adiponitrile facility currently under construction is expected to be put into operation in Q1 2022. The Phase III 100,000 MT/year adiponitrile capacity is currently being designed, and it is expected to be put into operation in 2023.
Adiponitrile is the key raw material for the production of nylon 66. However, adiponitrile production has high technical barriers, and the supply of adiponitrile is monopolized by companies from leading chemical countries, such as the United States, etc.
As adiponitrile has been monopolized by foreign countries for a long time, the National Development and Reform Commission (NDRC) has issued three documents in the past 10 years to encourage Chinese companies to achieve successful synthesis technology to promote the localization of adiponitrile technology.
Some local chemical companies have continuously devoted themselves to the development of adiponitrile technology for years. However, adiponitrile production entails a long process with a complicated catalyst system and high technical barriers. A few years ago, some companies built adiponitrile facilities. Afterwards, they had no choice but to shut down the facility due to high costs and explosion accidents.
In July 2019, Huafon built the first industrialized 50 KMT/year adiponitrile facility in China. It was the first industrial project in China to produce adiponitrile and the first adiponitrile project in China to use self-developed technology. Up to present, it has produced more than 100 KMT of high-quality adiponitrile.
Huafon made a major breakthrough in the development and innovation of the process route from adipic acid to adiponitrile in 2019. After its technical breakthrough, it built a complete supply chain from benzene to adipic acid, adiponitrile and adipic diamine, and to nylon 66 for the very first time in China. Hexanediamine is the key raw material used to synthesize nylon 66. Hexanediamine is from adiponitrile, which has always been considered as a core chemical product for nylon 66.
Globally, the butadiene method, acrylonitrile method, and adipic acid ammonification method are currently the three methods used to produce adiponitrile. At this point, the butadiene method and acrylonitrile method are still fully monopolized by foreign companies.
By using the adipic acid method, there are three technical difficulties: 1) Nitrile reactor is used as the core equipment; 2) Reuse of the by-products from adipic acid ammonification (especially in the early stage of production, the transportation of tar residue with high viscosity might be troublesome); 3) The adiponitrile produced by adipic acid ammonification method has poor quality.
In terms of the innovative achievement of Huafon’s adiponitrile technology, the experts have given their appraisal reasons. On the one hand, the supported Ru-M catalytic system for selective hydrogenation of benzene has been constructed, and a complete set of patent devices and processes with independent intellectual property rights have been designed to realize the large-scale and low-cost industrial continuous production of refined adipic acid. On the other hand, the new adiponitrile catalytic ammoniation preparation system from adipic acid has been self-developed and designed, breaking through the control limitations over reaction process and direction by original reaction facility, solving the high single consumption of adipic acid, difficult stability control, low adiponitrile content, serious waste of resources and environmental pollution faced by traditional processes.
In addition, the adiponitrile distillation and purification system were invented and designed to solve the separation problem of adiponitrile by-products, shortened the process, improved the adiponitrile impurity, so as to reduce the equipment investment, operation, and maintenance costs. The system has a long operation cycle with good stability.
Furthermore, the experts also believe that the project has developed the hexanediamine three-phase reaction synthesis system, which has solved the problem of uneven distribution of gas-liquid-solid in large reactors, improved the reaction efficiency, reduced the generation of side reaction products, recycled the alkali liquor in the entire process, and solved the blockage problem of the reaction system.
At the same time, the project realized the comprehensive utilization of the by-products from adiponitrile/hexamethylenediamine, reduced the unit consumption of adipic acid, solved the separation and purification of the by-products from adiponitrile/hexamethylenediamine, and obtained high value-added products and irreplaceable products.
Up to present, the project has obtained 10 patents and 8 utility models in China. Meanwhile, it also made and revised three industrial standards, corporate standards, and enterprise standards.
According to Huafon’s14th Five-Year Plan, after the 50 KMT/year adiponitrile project successfully achieved industrialization in 2019 at the company’s Chongqing plant, another 50 KMT/year adiponitrile facility was put into the trial production this year. The Phase II 100,000 MT/year adiponitrile facility currently under construction is expected to be put into operation in Q1 2022. The Phase III 100,000 MT/year adiponitrile is currently being designed, and it is expected to be put into operation in 2023.
Source: Chemical New Materials