The aviation industry is responsible for 14% of all CO2 emissions associated with transport in Europe, making it the second biggest source of emission. In order to reduce this high emission, sustainable aviation fuels (SAF) such as Alcohol-to-Jet Synthetic Paraffinic Kerosene (ATJ-SPK) are being developed, but they suffer from drawbacks like high resource costs, high operating temperatures, and low efficiency in terms of energy and carbon. This PhD project aims to address these issues through developing a low temperature aqueous route where we will develop a multifunctional catalyst that will participate in an aqueous poly-aldol condensation-hydrogenation route. The project involves four work packages, with the first two focusing on studying the impact of different catalyst active sites (acid, base, and metal) and operating conditions on the reaction's selectivity towards long chain alcohols. The third package involves testing the catalyst using realistic mixtures of crude bioethanol, acetaldehyde, and hydrogen. Finally, the fourth package entails developing process model for the overall process.