Aniline Derived from Plants
Improved CO2 Footprint
About five million metric tons of aniline are produced annually worldwide; the total volume has been increasing by an average of about five percent every year. Until now, only fossil raw materials had been used for the production of aniline, which plays an important role in the chemical industry and is used as starting material for numerous products.
The industry currently derives aniline from benzene, a petroleum-based raw material. But industrial sugar, which is already derived on large scale from, for example, feed corn, straw and wood, can be used instead. Covestro AG, Leverkusen, Germany, has scored a breakthrough in research. Together with partners the company has developed a completely new process, initially in the laboratory.
The newly developed process uses a microorganism as a catalyst to first convert the industrial sugar into an aniline precursor. The aniline is then derived by means of chemical catalysis in a second step. “This means one hundred percent of the carbon in the aniline comes from renewable raw materials,” explains Covestro project manager Dr. Gernot Jäger. Covestro is working with the University of Stuttgart, the CAT Catalytic Center at RWTH Aachen University, and Bayer AG to further develop the process. The long-term research project will receive funding for a period of two and a half years through the FNR (Fachagentur Nachwachsende Rohstoffe e.V.), a project agency of Germany’s Federal Ministry of Food and Agriculture (funding code: 22010215).
“The process currently under development uses renewable raw materials and produces aniline with a much better CO2 footprint than that manufactured with standard technology,” says Jäger. “This also enables our customers to markedly improve the CO2 footprint of their aniline-based products.” And the reactions would take place under milder conditions. The ecological aspects of the process are also being thoroughly evaluated by external institutes.
With a production capacity of about one million metric tons, Covestro is among the leading producers of aniline. The company requires aniline as a precursor for rigid polyurethane foam, a highly efficient insulating material used in buildings and refrigeration systems.
“The market is showing great interest in ecologically beneficial products based on renewable raw materials,” says Covestro Chief Commercial Officer Dr. Markus Steilemann. “Being able to derive aniline from biomass is another key step towards making the chemical and plastics industries less dependent on fossil raw materials and market fluctuations.” Following its success in the lab, Covestro plans to further develop the new process together with partners from industry and research. The first step is to upscale the process in a pilot plant with the ultimate goal of enabling the production of bio-based aniline on an industrial scale. That would be an unprecedented achievement in the chemical industry.