John Holbrey

Green chemistry (https://www.epa.gov/greenchemistry) is fundamental to our approach to science: We should reduce the generation of waste materials or energy, and efforts have to be directed towards the use of cleaner, more efficient chemical transformations and into the design and development of sustainable materials and manufacturing processes so that we do not unduly deplete or contaminate our available resources.

My research focuses on exploring how ionic liquids can be used in green chemical and engineering processes. This involves design, synthesis, measurement and then (hopefully) translation of this knowledge into delivery of useful results.

I completed my PhD studies with Joyce Lockhart at the University of Newcastle upon Tyne on the preparation of steroidal bioconjugated Tc-99m complexes as heart imaging agents., before undertaking postdoctoral positions with Duncan Bruce (at Sheffield University) and Klaus Praefcke (Technical University, Berlin) working on lyotropic and thermotropic platinum group metallomesogens. He then moved to Queen’s University Belfast, to work with Prof Ken Seddon on used of ionic liquids in industrial green and sustainable chemistry in 1996. After four years as a staff scientist at the University of Alabama (with Robin Rogers) he returned to Belfast to work on industry funded programs first with BP and then with PETRONAS, and was appointed Lecturer in Chemistry in 2011 and Professor in 2019.

I have published over 120 publications (cited over 16,000 times, h-index 57) and was placed at number 59 in the world in the 2011 Times Higher Education Supplement’s rankings of the top chemists of the past decade.

Our work largely centres on trying to determine where ionic liquids have a role addressing chemical and process problems in new and more effective ways. Highlights have included:

• Greener, more sustainable chemistry and processing: The first report on ionic liquid solvents for cellulose (JACS 2002, 124, 4974-4975) promoted unprecedented interest in the use of ionic liquids in bio-resource processing and lead to the US EPA Presidential Green Chemistry Challenge Award in 2005.

• Extraction and separations processes: Mercury from gas and oil In partnership with PETRONAS, we targeted the design of ionic liquids as solvents to capture mercury from oil and gas feeds. The worlds first commercialised supported ionic liquid process, Hycapure-Hg^TM, was developed for mercury capture with the first full-scale commercial trial started in October 2011. QUILL (the Queen’s University Ionic Liquids Laboratory) and PETRONAS won three global IChemE awards for Outstanding Achievement in Chemical and Process Engineering, Sustainable Technology, and Chemical Engineering Project of the Year in 2013 for this technology. We also were awarded the 2014 IChemE Nicklin medal and RSC Chemistry Technology Innovation Award in 2014. Continuing studies, including operando EXAFS at the Diamond Light Source have revealed even more detail into the mercury capture processes.

• Aromatic extraction and sensing with ionic liquids We have ionic liquids that respond with a colour change to the presence of polyaromatic molecules such as naphthalene, forming brightly coloured charge-transfer complexes. We have also found that the ionic liquids can be readily incorporated into porous silica ionogels, forming robust glassy solids which still respond in the same way in contact with aromatic molecules. Ongoing interest to see whether these materials can be used for sensing or dearomatisation of fuels.