Covestro has scored a research breakthrough for the use of plant-based raw materials in plastics production: Aniline, an important basic chemical, can now be derived from biomass. The materials manufacturer achieved this by collaborating with partners, including the University of Stuttgart, the CAT Catalytic Center at RWTH Aachen University and Bayer AG, on the development of a completely new process. Until now, only fossil-based raw materials had been used for the production of aniline, which plays an important role in the chemicals industry and is used as starting material for numerous products, said Covestro’s information.
About five million metric tons of aniline are produced annually worldwide; the total volume has been increasing by an average of about 5% every year. With a production capacity of around one million metric tons, Covestro is among the leading producers. The company requires aniline as a precursor for rigid polyurethane foam, a highly efficient insulating material used in buildings and refrigeration systems.
|Covestro is among several hundred suppliers exhibiting at the co-located PLASTEC East and MD&M East event in New York City next week. Go to the PLASTEC East website to learn more about the event and to register to attend.|
“The market is showing great interest in ecologically beneficial products based on renewable raw materials,” said Covestro Chief Commercial Officer Dr. Markus Stilemann. “Being able to derive aniline from biomass is another key step toward making the chemicals and plastics industries less dependent on fossil raw materials and market fluctuations. With this, we are pursuing our vision of making the world a brighter place.”
Project Manager Dr. Gemot Jager commented, “The process currently under development uses renewable raw materials and produces aniline with a much better CO2 footprint than that manufactured with standard technology. This also enables our customers to markedly improve the CO2 footprint of their aniline-based products.” The reactions would take place under milder conditions, Jager noted.
The ecological aspects of the process are also being thoroughly evaluated by external institutes. 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, explained Covestro’s information. 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,” explained Jager.
When asked how much biomass it would take to replace the current five million metric tons that are currently being produced conventionally, Stefan Paul Mechnig, Covestro spokesperson, responded to PlasticsToday: “A world-scale bio-based aniline facility (300,000 tons per year, for example) would require less than 0.003% of the available global agricultural area. The European Bioplastics Association conducted a comparative study of the availability of viable arable land worldwide and its use for food and livestock feed, biofuels and materials (industrial bio-based plastics). The study showed that only 0.01% (2014) and 0.02% (2019) of the arable land available worldwide is used for bio-based plastics. This finding has been confirmed by other independent institutes. If all petroleum-based plastics produced worldwide (approximately 300 million metric tons annually) were replaced by bio-based variants, the agricultural land needed would amount to only 0.9% of all the arable land on the planet.”
With respect to the use of feed corn, and the sometimes controversial use of any type of food source either for animals or humans, Mechnig told PlasticsToday that the company checked different feedstocks besides starch crops (e.g., feed corn). Alternative feedstocks are, for instance, lignocelluloses (wood, straw) or sugar crops, he noted, as did the release.
“Although the land required for bio-based plastics is minimal and will remain so, concerns have been expressed about the use of food crops, such as corn, in applications other than for food and livestock feed,” said Mechnig, acknowledging this sometimes controversial issue. “Efforts are therefore being made to obtain sugars from second-generation biomass, such as lignocelluloses from straw or wood, which is unsuitable as food. This is already technically feasible today, and some biofuel production processes use second-generation biomass.
“Still, it must be emphasized that harvests from arable land depend to a great degree on climate and soil conditions, and not all plants can be cultivated effectively in all regions,” Mechnig added. “That is why it is important to use the world’s arable land with maximum efficiency to ensure sustainability and to always cultivate plants that can yield the largest harvests over the long term, regardless of whether or not they are food crops.”
Covestro’s press release also mentions that the 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.
The company is already using renewable raw materials in a number of different products. A hardener for coatings that the company developed is one example: Up to 70% of the carbon content is derived from plants. And CO2 is also increasingly being used as an alternative raw material. Used in place of petroleum, CO2 accounts for up to 20% of the raw materials used in a precursor for flexible polyurethane foam that Covestro began producing in 2016. The company is also researching and developing many more products based on CO2.
When asked if Covestro will be storing/using the CO2 released from the processing of the biomass for the production of plant-based aniline, Mechnig had no comment.