August 16, 2013, by sustainablenottingham
Where next for Green Chemistry?
Dr Alasdair Taylor, Business Science Fellow, reports on developments in Green Chemistry (previously posted on his attheinterface blog).
I recently attended the 6th International Conference on Green and Sustainable Chemistry. This post is intended as a summary of some of the key messages and information coming out of the conference. As there were a large number of presentations and parallel sessions, I was only able to go to between a third and half the talks so this post is not an exhaustive recounting of events. Much gratitude should go to the organising committee and the excellent team of helpers who produced an excellent programme and ensured the week went smoothly.
This month saw The University of Nottingham host the 6th International Conference on Green and Sustainable Chemistry. With over 200 delegates and representatives from industry and academia, it is clear the green chemistry remains a strong discipline with a wide reach and influence. Yet, as green chemistry pioneer Martyn Poliakoff stated in his opening remarks, certain aspects of the field face a more uncertain future. The exploitation of unconventional oil and gas reserves has greatly extended the lifetime of these fossil fuels. This has weakened one of the key principles of green chemistry, namely the use of renewable over depleting feedstocks by deriving chemicals from sources such as biomass and carbon dioxide. Will new, renewable technologies be able to compete in a world suddenly awash once again in abundant and cheap oil and gas?
If the breakdown of the conference talks is evidence, then research into biomass conversion is still going strong and will continue to characterise the field for the foreseeable future. Speakers highlighted ingenious solutions, from ionic liquids to supercritical fluids, for the conversion of often intractable biopolymers into smaller, usable chemicals. By working with synthetic biologists and engineers, green chemists can undoubtedly help boost the case for bio-based technologies by discovering how high value products can be extracted directly or made from the products of biorefineries. However, the use of biomass raises issues around competition with food production for agricultural land and, as some speakers outlined, the use of waste biomass as feedstocks may end up being preferred.
Biomass conversion was not the only topic covered during the three days. Other contributions ranged from the capture and incorporation of carbon dioxide into new chemicals to the manufacturing of novel reactor designs with 3D printers. Keynote talks included new atom economic approaches in total synthesis, liquid organic hydrogen carriers as a means of storing energy and new methods of biocatalysis. More unusual research presented included converting lobster shells into porous carbon materials, using plants to recover precious metals from roadside verges and making polymers from hops (and beer). The diversity of topics covered showed just how wide a field green chemistry has become in the past two decades.
A key message from the conference was that simply creating a green chemical solution to a single reaction or process step is insufficient to make significant impacts to an industrial process. Increasingly, a holistic, “cradle-to-cradle” approach is taken and the most successful examples involve the redesigning of a whole process to make it sustainable. A number of speakers from the pharmaceutical industry demonstrated how this works in practice, describing how completely re-developing synthetic pathways resulted in both 90% reductions in waste and economic gains. Through initiatives such as the American Chemical Society Green Chemistry Institute’s Roundtable, awareness of green chemistry has grown in the pharmaceutical industry. GSK have been particularly active, giving financial backing to state-of-the-art research facilities and generating solvent and reagent guides to inform the working practice of their employees.
In his “Future Perspective” lecture which closed the conference, Peter Wasserscheid raised a number of provocative points about the future of green chemistry. In particular he questioned whether the community’s reach was broad enough. Despite the good work that has been done with the pharmaceutical industry, he compared GSK’s relatively small carbon footprint with that of a power plant and asked if it was time green chemistry developed stronger links with the energy and materials sectors. Although many chemical-using companies promote their sustainability programmes, are they familiar with green chemistry and the solutions it can offer? As an example, Wasserscheid referred to a fundamental green chemistry metric, and set the challenge of determining the E-factor for a fracking process or the manufacture of a photovoltaic cell. If green chemistry is to expand its influence then quantifiable benefits, particularly in the bottom-line, are needed to convince industry to adopt new, sustainable technologies, and methodologies such as life-cycle analysis must become more robust.
Wasserscheid was keen to highlight that green chemistry is a practical field, providing tangible scientific and engineering solutions. In many aspects it is a remodelling of traditional chemical engineering but with a focus on achieving greater molecular complexity through sustainable methods. To break into new industries, practitioners must develop means to communicate key information between every step in the value chain between technical and non-technical groups. This is, perhaps, where the holistic philosophy behind green chemistry, rather than its practical application, comes to the fore. A good example given during the conference was the Green Product Design Network at the University of Oregon, which integrates green chemistry teaching into courses on architectural design, business and journalism. Where exposure to different kinds of thinking was reciprocated between chemists and other students, ideas were exchanged and new problem solving tools developed. It is this type of approach that will allow green chemistry to expand outside the purely scientific realm and achieve the goals Wasserscheid imagined.
In his closing remarks, Wasserscheid described green chemistry as making molecular science responsible for the future of the planet. Indeed, in a truly sustainable future the entire existence of every chemical will need to be understood but this is not a task that chemists can achieve by themselves. If green chemistry is to become wide-reaching and inclusive, it might need a name change.