TiO2 catalyst in ketonisation reactions to produce RBO

A method for producing renewable base oil and diesel fuel from a feedstock of biological origin, the method comprising:

• a) providing a feedstock, the feedstock including 2-95 wt % of a mixture of free fatty acids;
• 5-98 wt % fatty acid glycerols selected from mono-glycerides, di-glycerides and tri-glycerides of fatty acids;
• 0-50 wt % of one or more compounds selected from a list consisting of:
• fatty acid esters of the non-glycerol origin, fatty amides and fatty alcohols;
• wherein at least 50 wt % of the feedstock is a mixture of free fatty acids and fatty acid glycerols;
• and separating the feedstock from step a) into at least the following two feeds:
• a1) a free fatty acid enriched feed which has a higher concentration of free fatty acids than the feedstock and wherein the free fatty acids include C10-C24 fatty acids;
• and
• a2) one or more free fatty acid depleted feed(s) which has a higher concentration of compounds selected from mono-glycerides, di-glycerides, and tri-glycerides of fatty acids, and a higher boiling point than the free fatty acid enriched feed;
• b) subjecting the free fatty acid enriched feed to ketonisation under ketonisation reaction conditions in a presence of a ketonisation catalyst selected as metal oxide catalyst essentially containing titanium as the metal, where a content of an element potassium is 0.05 wt % or less, and where two free fatty acids react to yield a ketone stream, the ketone stream containing as a major part saturated ketones;
• c) subjecting the ketone stream to both hydrodeoxygenation under hydrodeoxygenation reaction conditions and to hydroisomerisation under hydroisomerisation reaction conditions, simultaneously or in sequence, to yield a deoxygenated and isomerised base oil product stream containing the renewable base oil;
• and
• d) transforming the one or more free fatty acid depleted feed(s) into a diesel product by subjecting the one or more free fatty acid depleted feed(s) to both hydrodeoxygenation under hydrodeoxygenation reaction conditions and to hydroisomerisation under hydroisomerisation reaction conditions, simultaneously or in sequence, to yield a deoxygenated and isomerised diesel product stream containing the diesel fuel.