A process is disclosed for converting aquatic biomass to a bio-oil. The process comprises mixing the aquatic biomass with a particulate catalytic material; subjecting the aquatic biomass to a catalytic cracking reaction to form a reaction mixture comprising a bio-oil; and isolating the bio-oil from the reaction mixture. Preferably the process is integrated with a plant for producing aquatic biomass, so that heat and CO2 generated during the process may be used in the production of aquatic biomass.