A new approach was added to the localization of adiponitrile. The two-step process with methanol and butadiene as raw materials passed the evaluation

A new breakthrough has been made in the preparation process of adiponitrile, which has long restricted the development of China's nylon 66 industry
.
On April 30, the two-step process for producing adiponitrile using methanol and butadiene as raw materials developed by Beijing Daosike Mining Equipment Technology Co.
, Ltd.
, a wholly-owned subsidiary of Bozun Investment Group, passed the evaluation of scientific and technological achievements organized by China National Chemical Industry Information Center.

.
The evaluation expert group composed of Zhang Liqun, academician of the Chinese Academy of Engineering and vice president of Beijing University of Chemical Technology, and Yue Guangxi, academician of the Chinese Academy of Engineering and professor of the Department of Thermal Energy Engineering of Tsinghua University, believe that the new process innovation is outstanding, and the key technology has reached the international leading level, and it is recommended to speed up industrial application
.

"The new two-step process for producing adiponitrile we developed uses methanol or calcium carbide tail gas with huge domestic production capacity as raw materials, and sequentially passes through the formamide preparation unit and the hydrocyanic acid preparation unit to obtain hydrocyanic acid, and hydrocyanic acid is then combined with butadiene via During primary cyanation and secondary cyanation, 80% to 90% of the product is adiponitrile, and 10% to 15% of 2-methylglutaronitrile (MGN) is by-product
.
We also have a good process route, which can be hydrogenated to generate 2-methylpentanediamine, and then cyclized and dehydrogenated to obtain high value-added 3-methylpyridine, which is used to produce vitamins and pharmaceutical intermediates
.
" Ying Guohai, chief engineer of Bozun Investment Group, introduced the technical route of the new process and the research results obtained
.

After listening to the report, the expert group believes that the new process has made three major innovations in the complete set of process technology and key equipment: First, the process of preparing methyl formate based on methanol, ammoniation to prepare formamide, and high temperature pyrolysis to prepare hydrocyanic acid has been developed.
Technology, including unique micro heat exchanger technology, MnO/SiO₂ non-precious metal catalyst and low energy consumption separation and purification technology
.
The selectivity of hydrocyanic acid reaches more than 94%, and the purity reaches 99.
95%
.
The hydrocyanic acid preparation unit is the first in China
.
The second is to independently develop a highly active and highly selective ligand catalyst system with a ligand concentration of 95%, breaking through the foreign patent blockade
.
The third is to develop a new production process and complete set of equipment for the preparation of adiponitrile in two steps.
The total yield of adiponitrile and by-product MGN in the pilot plant is over 95%, and the concentration of adiponitrile reaches 99.
6%
.
The expert group believes that the overall energy consumption of this complete set of technical devices is lower than the industry level, which can effectively reduce construction investment and operating costs, and provide a new way for the localization of adiponitrile
.

"The raw material methanol used in this new process can be either coal-to-methanol or calcium carbide tail gas.
This new process is useful for alleviating the problem of oversupply of domestic methanol, realizing the comprehensive utilization of calcium carbide tail gas, and opening up the transition from coal chemical industry to coal.
The channel for the transformation of fine chemicals is a good choice
.
Previously, we have completed the design and construction of a 500-ton/year adiponitrile pilot plant
.
At present, the 10,000-ton-level adiponitrile and downstream high-end new material equipment will be built in Ningdong base, which will fill the gap of nylon industry in Ningdong base after completion
.
" said Geng Haitao, chairman of Bozun Investment Group
.

It is understood that adiponitrile is a key intermediate in the production of nylon 66, mainly used for the production of nylon intermediate hexamethylene diamine.
In recent years, although the market demand for nylon 66 has continued to grow, the nylon 66 industry has shown an oligopolistic pattern in the world.
Its key The point lies in the matching of the raw material adiponitrile
.
Subject to the key raw material adiponitrile, domestic nylon 66 is nearly 30% dependent on the outside world, and the preparation of adiponitrile has become a "stuck neck" technology in the field of new materials in China
.
In 2019, the National Development and Reform Commission listed the 10,000-ton adiponitrile production plant as an encouraged project to promote the localization of adiponitrile technology
.
The new two-step process for the production of adiponitrile developed by Doske and the 10,000-ton-scale industrialization plant planned and constructed in the Ningdong base have opened up the channel for the transformation from coal chemical industry to coal-based fine chemical industry, and formed a completely independent intellectual property rights.
The industrial chain from coal chemical industry to high-end fine chemical industry
.