Technological researches in the adipic acid production field started in the Institute in 1959 with the works on catalytic oxidation of cyclohexanol with nitric acid under pressure.
In 1963 a 4500 tpy adipic acid unit was commissioned based on intermittent recovery of about 50% of adipic acid from aqueous layer in Severodonetsk Chemical Complex.
In 1970 the Institute made available design basis and procedure for designing of a 25000 tpy adipic acid plant for Severodonetsk Chemical Complex.
In 1975 a 30000 tpy adipic acid plant completely supplied by BASF (Germany) was put on stream in Severodonetsk PO Azot, it was the first large-scale plant of such kind in the USSR. The Institute was responsible for acceptance of the documentation from the Licensor, development of basic and detail design for civil works, construction and erection supervision.
The Institute developed the treatment method for nitrous gases to remove nitrogen oxides in the absorber using cyclohexanol. The obtained clean gas containing dinitrogen oxide is an additional marketable product. This method formed the basis for development of adipic acid process to produce 25 - 30 ths. tpy with coproduction of 10 ths. tpy of marketable dinitrogen oxide.
The Institute carried out researches on cyclohexanol oxidation with nitric acid over copper-vanadium catalyst, adipic acid crystallization and drying as well as on methods to determine nitrates and water in the end product. In 1977 the Institute provided initial data for designing of adipic acid plant with a capacity of 25 ths. tpy for Rovno PO Azot using the improved technology.
The adipic acid plant for Rovno PO Azot was designed with a capacity of 50 ths. tpy realized in two units, each 25 ths. tpy, using domestic equipment. Research results, experience gained in startup and commissioning of a similar plant built for Severodonestk PO Azot based on BASF technology were used by the Institute when designing. In the 80s the domestic production scheme was essentially changed as compared with imported plant, resulting in higher technical level of adipic acid production.
Oxidation reactor system as circulation loop combining the reactor, stripper and rectifying vacuum-column into one system was used in the process system, with part of reaction solution discharged from the rectifying column bottom to separate adipic acid.
In 1992 the adipic acid plant was upgraded with an additional circulation loop to provide separate supply of part of circulating working mixture that was not stripped.
Furthermore the Institute developed the technology to continuously supply nitrogen oxides to the reactor system by washing of waste nitrous gases with feed alicyclic alcohol. This technology allowed to produce additional 'crude' adipic acid and lower dicarboxylic acids mixture (LDA) from aqueous-acidic effluent by oxidation with mother liquor of crystallization I stage. The purpose of the reactor system in the adipic acid process is to ensure complete oxidation of organic feedstock to prevent non-oxidized organic matters from entering the other process stages. For this purpose the Institute proposed to treat the reaction solution (high in cyclohexanol, up to 60%) by heating in the reactor II stage – 'maturing' reactor - before to send it to adipic acid separation. The presence of the 'maturing' reactor ensures process safety and allows to decrease impurities content in the reaction solution.
In 1998 at SC Rovnoazot there was commercialized the production unit for lower dicarboxylic acids mixture with high-efficiency carbon and ion-exchange cleaning of acids solution from resins and catalyst. Recovered copper-vanadium catalyst is regenerated by passing aqueous solution generated after dicarboxylic acids separation through ion-exchange resin followed by treatment of the latter by nitric acid, and returned to the process cycle.
Researches aimed at deeper treatment of wastes and operating fluids carried out by the Institute allow to increase marketable product output per 1 ton of processed benzene up to 50%. In 1998 the plant was supplemented with a system for production of purified mixture of succinic, glutaric and adipic acids.
In 2006 for JSC Rovnoazot the Institute developed the basic design of the unit to produce succinic, glutaric and adipic acids as individual marketable products.