New and very effective recycling technology to transform used tires into raw materials for rubber and nylon

Billions of tires are thrown global each year, and this is identified as one of the main causes of pollution of the serious environment. A research team from the Kaist Department of Chemistry has managed to selectively convert waste tires into high purity cyclical alkenes, which are high value chemical materials used as raw materials for rubber or nylon fibers. This is assessed as a new turning point in the recycling of waste tires.

The research team of Professor Sofhyuk Hong of the Kaist Department of Chemistry has effectively resolved the problem of waste tires by developing a continuous double catalyst reaction system. Research is published in the newspaper Chem.

Waste tires are made up of a synthetic complex and natural rubberand their physical strength And sustainability are maximized by including additives such as silica, carbon black and antioxidants. In particular, the retication between the rubber chains is formed by the vulcanization process, giving them a structure resistant to heat and pressure, which is one of the main reasons why recycling Waste tires is difficult.

Until now, recycling of waste tires has mainly reached pyrolysis or physical crushing recycling methods. The pyrolysis method is a technology that decomposes polymer channels has high temperatures From 350 to 800 ° C to convert them into fuel oil, but it clearly has limits such as high energy consumption, low selectivity and the production of low -quality hydrocarbon mixtures.

To solve these problems, the research team has developed a method to convert waste rubber into useful chemicals using two catalysts. The first catalyst helps to break down the rubber molecules by modifying their link structure, and the second catalyst creates cyclical compounds through an annular closing reaction.

This process shows high selectivity of up to 92% and a yield of 82%. Cyclopentnene produced can be recycled in rubber, and cyclohexene can be used as a raw material for nylon fibers, which makes them very precious industrial.

The research team successfully applied the system developed to real thrown waste tires, achieving selective conversion into high purity cyclical alkenes. Unlike the existing pyrolysis method, this is assessed as a new turning point in the recycling of waste tires because it can produce high value chemical materials by catalytic reactions of low temperature precision.

In addition, this technology can be widely applied to various types of synthetic rubber and waste rubber, attracting attention as a key technology which can contribute to the realization of a circulating resource economy.

Professor Roonhyuk Hong said: “This research presents an innovative solution for chemical recycling of waste tires, and we plan to develop new generation high -efficiency catalysts and establish a marketing base to improve economic viability“Continuing to say:” Our goal is to help solve the problem of plastic waste thanks to basic chemistry. “”