doi:10.1016/j.enconman.2016.04.010engRemon, J.Arcelus-Arrillaga, P.Garcia, L.Arauzo, J.Production of gaseous and liquid bio-fuels from the upgrading of lignocellulosic bio-oil in sub- and supercritical water: effect of operating conditions on the processART-2016-99557This work analyses the influence of the temperature (310–450 C), pressure (200–260 bar), catalyst/biooil mass ratio (0–0.25 g catalyst/g bio-oil), and reaction time (0–60 min) on the reforming in sub- and supercritical water of bio-oil obtained from the fast pyrolysis of pinewood. The upgrading experiments were carried out in a batch micro-bomb reactor employing a co-precipitated Ni–Co/Al–Mg catalyst. This reforming process turned out to be highly customisable for the valorisation of bio-oil for the production of either gaseous or liquid bio-fuels. Depending on the operating conditions and water regime (sub/supercritical), the yields to upgraded bio-oil (liquid), gas and solid varied as follows: 5–90%, 7–91% and 3–31%, respectively. The gas phase, having a LHV ranging from 2 to 17 MJ/m3 STP, was made up of a mixture of H2 (9–31 vol.%), CO2 (41–84 vol.%), CO (1–22 vol.%) and CH4 (1–45 vol.%). The greatest H2 production from bio-oil (76% gas yield with a relative amount of H2 of 30 vol.%) was achieved under supercritical conditions at a temperature of 339 C, 200 bar of pressure and using a catalyst/bio-oil ratio of 0.2 g/g for 60 min. The amount of C, H and O (wt.%) in the upgraded bio-oil varied from 48 to 74, 4 to 9 and 13 to 48, respectively. This represents an increase of up to 37% and 171% in the proportions of C and H, respectively, as well as a decrease of up to 69% in the proportion of O. The HHV of the treated bio-oil shifted from 20 to 35 MJ/kg, which corresponds to an increase of up to 89% with respect to the HHV of the original bio-oil. With a temperature of around 344 C, a pressure of 233 bar, a catalyst/bio-oil ratio of 0.16 g/g and a reaction time of 9 min a compromise was reached between the yield and the quality of the upgraded liquid, enabling the transformation of 62% of the bio-oil into liquid with a HHV (29 MJ/kg) about twice as high as that of the original feedstock (17 MJ/kg).2016http://zaguan.unizar.es/record/6186710.1016/j.enconman.2016.04.010http://zaguan.unizar.es/record/61867oai:zaguan.unizar.es:61867info:eu-repo/grantAgreement/ES/DGA/GPTinfo:eu-repo/grantAgreement/ES/MINECO/BES-2011-044856info:eu-repo/grantAgreement/ES/MINECO/EEBB-I-14-08688info:eu-repo/grantAgreement/ES/MINECO/ENE2010-18985info:eu-repo/grantAgreement/ES/MINECO/ENE2013-41523-REnergy Conversion and Management 119 (2016), [59 pp.]by-nc-ndhttp://creativecommons.org/licenses/by-nc-nd/3.0/es/info:eu-repo/semantics/openAccess