STUDY OF CATALYTIC HYDROTREATMENT OF PYROLYSIS BIO-OIL

Pyrolysis bio-oil is a promising 2nd generation biofuel. To achieve a more widespread use of bio-oils, their negative properties caused by high oxygen content must be improved. Over the last 30 years of study of bio-oil upgrading, catalytic hydrotreatment seems to be preferred to catalytic cracking, as hydrotreatment affords higher yields of desired products having better quality and higher degree of deoxygenation. The main problem observed during hydrotreatment of bio-oils is the formation of condensed high-molecular-weight products, which causes plugging of the catalyst bed and thus, shutting down of the reactor. This work summarises possible problems observed during hydrotreatment of bio-oils, their causes and possibilities how to minimize them. The work also presents results obtained from initial continuous hydrotreatment experiments of a bio-oil from ablative flash pyrolysis of straw.