In the biobased economy, green chemistry will play an important role. But many aspects of it need further research and development. Almost all petrochemical technology will have to be adapted of even reinvented: separation and process technologies, catalysis, and analytical techniques. And all branches of biotechnology will have to come to full bloom.
Separation technology
For better production of chemicals from biobased resources, we need better separation technologies to extract the desired product from the biochemical reaction solution. Europe has a reputation in process and separation technologies, based however on relatively simple petrochemical reactions. Green chemistry requires a lot of new fundamental and applied research in these areas.
For it makes quite a difference to process fluids or solids, solutions in water or in organic solvents, thermally stable molecules or intricately complex proteins or enzymes. Separation technology will become an integral part of green chemical technology. In petrochemical markets, the last infinitesimal cut in production costs may determine whether you are a winner or a loser – in green chemistry it will be separation technology to make that difference. European petrochemical separation technology is very good, but this technology will have to evolve into separation methods for very diluted solutions with many similar substances. Researchers make headway into these problems; a small technological research company testifies to this, which has succeeded in concentrating algae from a .1% solution to a 30% cake, whereas 25% is the minimum for subsequent industrial processing. Separation technology will evolve into one of the key technologies of green chemical production.
Scaling up
For many products and processes, green chemistry still is in its lab phase. For commercial production this needs to be scaled up. We need to prove the technical viability of green chemical processes on a pilot plant scale, from where we can move to a demo scale to prove their economic viability. That is what we need to show the world that we can perform these processes commercially. And only then will green chemistry be able to take over petrochemistry´s role.
At present, these developments start to make a take-off. In the Netherlands, Delft Technical University and DSM took the initiative for a multipurpose pilot plant in Delft , to be used by third parties as well. A similar plant is going to be constructed in Ghent. That is a breakthrough. Not merely in technology, but also in cooperation and trust among companies which until now were very keen on protecting their process data.
A step further along this road would be the construction of a demo plant (costs about € 200 million). Finance appears to be the principal bottleneck. Big oil and petrochemical companies will not invest in such a plant on their own. Government will have to take the initiative to attract venture capital. Maybe in public-private partnerships, together with green chemical or agribusiness. But even so, this does not suffice in itself, nor would it lead to new principles of scaling up, or to new reactor technology. Production of higher-value products needs the development of new process technology.
Catalysis
The new green chemistry points out once more the importance of catalysis. Catalysts are auxiliary compounds which initiate or accelerate a chemical reaction, but remain unaltered themselves. New catalysts should be adapted to hydrophilic molecules in a water solution, whereas petrochemistry makes use of hydrophobic molecules in organic solvents. Enzymatic catalysis will increase appreciably in importance and use. In addition, preparation of biobased resources requires both heterogeneous and homogeneous catalysis (for reactions is the solid and liquid phases, respectively) for completely new reactions and applications. Researchers in all three catalytic areas should cooperate far more closely. Europe is renowned for its knowledge of petrochemical catalysis. With respect to the Netherlands, the name of the Dutch School of Catalysis has been coined, not an institute, but a world famous loose conglomerate. Science will have to develop enzymes for preparation of vegetal matter or waste for further processing by modified yeasts, fungi or bacteria. Some of those enzymes have been developed, others are still in the research phase.
Catalytic scientists will have to meet high demands. They will have to cooperate to an unknown extent. Catalytic selectivity should at least equal that of nature, whereas catalytic productivity should be much better. Complexity and multifunctional properties of biomass will require concurrent use of a number of catalysts for sufficient productivity and reactivity (cascade catalysis, multiprocess catalysis etc.). In analogy to nature, many reactions will have to proceed simultaneously without hampering each other, rather: while reinforcing each other through smart feedbacks.
Analytical chemistry and certification
Finally, we need analytical chemistry which will have to unravel complex systems, instead of detecting single compounds or products. Biochemical reactions result in a broth containing many resembling compounds, which renders it more difficult to measure each concentration, and assess whether the reaction has come to an end. Moreover, in the future we will want to know at a glance all processes in a dynamic system, like a living cell, in order to stimulate them in the desired direction. And as long as petrochemical and biochemical products are being sold alongside, analytical chemistry will also have to certify to what extent a product is fossil based, and to what extent it is biobased. C14 technology can easily do that.
In short, all chemical branches will have to exert themselves to realize the biobased society.
Courtesy WTC, Dutch Scientific and Technological Committee for the biobased economy