Towards environmentally sustainable catalysts:Atomic level engineering of metallic catalysts for acrylic

Acrylic is a transparent plastic material, 100% recyclable, known since the Second World War and used in a large number of everyday applications due to its highly desirable properties. These include optical transparency, surface hardness, UV stability, chemical resistance, and biocompatibility. This makes acrylics the material of choice for building, car windows, screens for electronic devices as well as contact lenses, cavity filling and bone cement.
The acrylic is produced from the monomer methyl methacrylate (MMA), a colourless liquid which is traditionally manufactured by methods that are environmentally unfriendly and energetically inefficient. The standard route for MMA involves acetone and hydrogen cyanide where for each kg of MMA, a 1.1 kg of toxic salt is produced. The disposal of it (3 billion kg/year produced) is energetically and environmentally costly. Hence, alternative routes are highly desirable. Recent efficient approaches are based on heterogeneous catalysts, hence highly efficient catalysts are the key for environmentally (low Carbon footprint) friendly production of acrylics.
Recently, Lucite international (one of the main world producers of acrylic and based in UK) has developed a new type of metallic based heterogeneous catalysts that can significantly improve the efficiency of the reactions for the production of MMA. The new catalysts are clusters of a small number of metallic atoms (between 1 and 10) stabilised by organic molecules in order to avoid particle formations. The visualisation of such materials on a support requires very high spatial resolution.
An in house developed In-situ scanning transmission electron microscope at the University of York will allow not only to image such structures but also to study their interaction with gases and moisture environment, as well as the cluster evolution as a function of temperature on different substrates.
This study, in collaboration with Lucite International, will focus on the characterisation of these new catalysts down to the atomic scale in controlled environmental conditions, providing a correlation between the catalysts atomic structure and their functionality. This is the key for the optimisation of these catalysts for real industrial processes.