The UK is committed to stringent carbon budget commitments requiring complete decarbonisation of the energy system by 2050. It is generally expected that low carbon liquid fuels will form a key component of the UK's mid-term decarbonisation efforts (2025-2040) and that in the long term (2040-2050) deployment of bioenergy with carbon capture and storage will be required to meet UK and global net negative carbon commitments. Development of low-carbon liquid fuels is therefore essential for the UK future low carbon energy system.
Biomass is the only sustainable feedstock to produce renewable organic chemicals. One of the most interesting chemicals that can be produced from lignocellulosic biomass is Y-valerolactone (GVL). GVL can be blended with gasoline up to 10% and is a precursor to liquid alkanes in the diesel and jet fuel range, as well as some useful chemicals with applications as eco-friendly solvents and in polymers production.
Currently the process of GVL production from biomass-derived feedstocks is based on a cascade process, starting with the fractionation of lignocellulosic biomass and sugar productions. Subsequently, the sugars will undergo acid catalysed transformation to levulinic acid, followed by noble-metal catalysed hydrogenation of levulinic acid to GVL using H2 gas. However, this approach comes with some significant drawbacks such as the application of expensive metal catalysts (e.g. Ru or Pt) for the levulinic acid hydrogenation step and also high pressure H2 (greater than 30 bar) which can have a huge negative impact on the process safety, sustainability and economics.
Alternatively, hydrogenation can be performed using liquid hydrogen donors such as renewable alcohols. This so-called "catalytic transfer hydrogenation" (CTH) process can be catalysed by inexpensive metals (e.g. Zr or Ni), allowing hydrogen transfer from the H-donor to the target molecules.
Through experimental methodologies, this project will develop a new energy-efficient and cost-effective catalytic process for GVL production from bio-based feedstocks by utilising alcohols as hydrogen source. New and commercially relevant solid catalysts will be developed through a rigorous bottom-up approach to catalyst design, synthesis, characterisation, and testing.