In the five years since the CAT Catalytic Center, a cooperative research effort between Bayer MaterialScience and RWTH Aachen University, was established, the center has grown into an important interface between science and industry. One of its major activities is research into the use of carbon dioxide as an alternative building block for plastics.
The "Perspective on Innovation 2012" program organized by Bayer in Leverkusen (Germany) included a visit to the CAT Catalytic Center at the technical university in the nearby medieval city of Aachen. This collaboration between the university and Bayer has successfully secured funding for another five years. Not only has the center become a magnet for top researchers around the world, it offers the university a window into the long-term problems and needs of the chemical industry.
"On the other hand, a company like Bayer obtains valuable input for its research and development pipeline, especially through the open innovation approach," said Christophe Gürtler, head of the Bayer MaterialScience catalysis program and director of the CAT Catalytic Center.
Or, as Ernst Schmachtenberg, rector at RWTH Aachen University explained: "Here at the University, we are good at taking money and turning it into knowledge. And Bayer is just the opposite: good at taking knowledge and turning it into money."
Chasing the "dream reaction"
Thus viewed, the collaboration between the two is a match made in heaven. Yet it is also one that is bearing fruit, especially in the field of CO2-based polymers. CO2-based polymers have long been an appealing idea - if only the problem of the low reactivity of CO2 could be overcome, a problem confronting scientists for decades. The sheer amount of energy needed to enable a reaction with CO2 had up to now rendered this an inefficient exercise in futility. It was, said Christophe Gürtler, "a dream reaction."
In 2009, the Dream Reaction project was initiated by Bayer to develop the catalysis technology needed for the efficient use of CO2 as a chemical feedstock - or, more specifically, as a source of carbon for the manufacture of polyether polycarbonate polyols, one of the two reaction components in polyurethanes, to reduce dependency on petroleum-based propylene oxide, the conventional raw material.
The subsequent successful development of a catalyst that could put CO2 to efficient use on a laboratory scale led to the launch of the "Dream Production" project. This involved the creation of a consortium consisting of Bayer, German energy provider RWE Power and researchers from RWTH Aachen University, to build a technical-scale pilot plant at Chempark Leverkusen.
Industrial production in 2015
This pilot plant came on stream in February 2011, using CO2 from the RWE coal-fired power plant in Niederaußem outside of Cologne to produce CO2-based polyol. Industrial production is scheduled to begin in 2015. Although this will initially serve as a building block for flexible polyurethane foam, the range of applications will soon be expanded to include coatings and thermoplastic polyurethanes, Gürtler explained.
The project continues to run successfully, with the foams produced showing properties comparable to conventionally produced foams, and a flame retardancy that is even somewhat superior, due to the incorporation of the carbonate groups.
The CO2RRECT project (CO2-Reaction using Regenerative Energies and Catalytic Technologies) takes sustainable CO2 technology a step further. This project is an alliance of 13 partners, in which, according to Walter Leitner of RWTH Aachen University, excess green - solar and wind - energy that would otherwise be wasted "is sequestered and brought into the chemical industry to produce hydrogen in an elegant and efficient way." He clarified this further: "This occurs by splitting water into its constituent elements hydrogen and oxygen, in a process called electrolysis."
Waste CO2 from the RWE pilot power plant reacts with the hydrogen to produce chemical intermediates, such as carbon monoxide and formic acid, which can be used in turn to manufacture not only polyurethanes but also high-performance polycarbonates. "Although right now we're concentrating on polyurethane," said Gürtler. "It's an existing market, with a drop-in solution. High-molecular PC is new: we'll see how it works out."
He continued: "To react the CO2, Bayer has developed a (zinc-based) catalyst that is a significant improvement over the state of the art." Furthermore, Bayer has developed a chemical reactor for CO2-reforming that is currently under construction as a demonstration facility, which offers significant cost advantages over conventional plants. The new reformer is scheduled to go into operation at the INVITE research center, run jointly in Leverkusen by Bayer Technology Services and Dortmund Technical University, in spring 2013.
"Our partners have also developed a water electrolyzer that can be started up and shut down in seconds," explained Gürtler. Because it can go into operation whenever excess or extremely cheap power is available, the current fluctuations that are unavoidable when using regeneratively produced electricity can be reliably managed.
A demonstration system will be built in the near future.