DOI: 10.1002/cssc.200700049 Coprocessing of Oxygenated Biomass Compounds and Hydrocarbons for the Production of Sustainable Fuel Marcelo E. Domine, Andre C. van Veen, Yves Schuurman,* and Claude Mirodatos [a] Climate changes related to global warming impose rapid ac- tions to reduce greenhouse gas emissions, especially carbon dioxide. As the transportation sector is one of the main con- tributors, changes in this sector that are compatible with cur- rent technologies can have a strong impact. To focus on carbon-neutral renewable resources as a replacement for fossil fuels seems appropriate, as this will have an immediate impact. Processing biomass is a perspective for the direct production of liquid fuels and chemicals. [1,2] Currently, the world produc- tion of bioethanol and biodiesel from vegetable oils covers a mere 1% of global transport fuels. [3] Production of biofuels has doubled over the past 5 years, and reports indicate that if this trend continues biofuels could supply at least 35% of US trans- port fuels and 20–30% of the EU’s oil in the next 25 years. [3,4] Nevertheless, biofuels have their own environmental and stra- tegic costs, as they are derived from agricultural sources grown in net competition with food production. Given the huge capacities of fuel involved in transportation, a rapid change can be achieved only by using existing infrastructures and guaranteeing the same quality of the final fuels. Thus, it seems logical to investigate first options for introducing bio- mass components into existing refinery infrastructures. Ideally, the production of biofuels could be almost instantaneously achieved by co-processing of biomass-derived oils in standard units along with conventional crude oil. This co-processing of renewables and hydrocarbons in an existing refinery will be economically more competitive than processes such as Fisch- er–Tropsch processes to obtain fuels from the gasification of biomass [5] and biodiesels derived from vegetable oils. [6] In this sense, non-competing lignocellulosic biomass sources derived from forestry and industrial wastes are cheaper and present the most promising alternative that will eventually dominate the market in the future. [7] Up to now, different types of gasifi- cation processes commonly perform the conversion of bulky biomass materials into easier treatable intermediates. Pyrolysis, partial oxidation, and steam gasification are the most common ways to obtain gaseous products, as well as liquids and solids, from biomass resources. [1,8] Fast pyrolysis of biomass performed under suitable condi- tions can yield, besides gaseous and solid products, 75 wt% of a liquid or condensable biomass-derived oil. [9] Pyrolysis oils ob- tained from lignocellulosic biomass are complex mixtures (> 200 components) of mainly oxygenated compounds emulsi- fied in water. Constituents are acids, aldehydes, ketones, alco- hols, glycols, esters, ethers, phenols and phenol derivatives, as well as carbohydrates and derivatives, and a large proportion (20–30 wt%) of lignin-derived oligomers. [10] In the last years, demonstrators for the upgrading of pyrolysis oil by catalytic cracking processes were tested and indicated the production of low amounts of gasoline and important amounts of tars, chars, and coke, and irreversible deactivation of the catalyst, mainly as a result of the high oxygen content in the feed. [11–16] The transformation of oxygenated model compounds into liquid fuels by cracking over acid catalysts has also been stud- ied. [17,18] Thus, although pyrolysis oils can be used as a renewa- ble feedstock for the production of transportation fuels, direct feeding of the entire pyrolysis oil into standard refinery reac- tors is not a straightforward task even after passing compulso- ry upgrading steps. [19] It is therefore necessary to integrate processes in large-scale units (e.g. fluid catalytic cracking (FCC), hydro treating) that can convert pyrolysis oils into automotive fuels at a lower cost than for small-scale plants dedicated to biomass processing or transesterification, thus attaining public acceptance at relative- ly low cost. To elucidate the possibilities of co-processing ap- proaches in FCC refinery units, we focused our study on the co-feeding of hydrocarbon and oxygenated compound mix- tures into a catalytic fixed-bed reactor simulating the FCC con- ditions in the range of 450–530 8C. We tested equilibrated FCC catalyst formulations, that is, catalysts that have already sus- tained several FCC cycles. Acetic acid, acetone, and isopropyl alcohol, chosen as model compounds and being representa- tive of pyrolysis oil, were co-injected along with isooctane, which represented the hydrocarbon feed (similar trends were observed with dodecane). The use of model compounds was motivated by preliminary results on real feeds that were com- plex to analyze and by a need for a better fundamental under- standing. In fact, the extensive knowledge that exists today on the mechanism of catalytic cracking stems mainly from experi- ments using small hydrocarbons. [20] The influence of the addi- tion of oxygenates on the cracking reaction was evaluated in terms of conversion and product distribution, as well as cata- lyst stability. A rigorous comparison of data obtained for cata- lytic hydrocarbon cracking in the presence and absence of oxy- genated molecules allows identification of those classes of oxy- genated compounds that must be eliminated from pyrolysis oils before their admission to FCC units. Figure 1 shows the conversion of isooctane at 530 8C over 10 reaction cycles for a catalyst-to-isooctane ratio of 15 g/g. During these cycles, the catalyst is regenerated by oxygen by keeping the temperature in the catalyst bed at 530 8C. The cat- alyst was stable during all 10 cycles. Low amounts of acetone, acetic acid, and isopropyl alcohol, 2 wt% of the hydrocarbon [a] Dr. M. E. Domine, Dr. A. C. van Veen, Dr. Y. Schuurman, Dr. C. Mirodatos Institut de Recherches sur la Catalyse et l’Environnement de Lyon UMR5236 CNRS—UCBL 2 Avenue Albert Einstein, 69626 Villeurbanne (France) Fax: (+ 33)472445399 E-mail: yves.schuurman@ircelyon.univ-lyon1.fr ChemSusChem 2008, 1, 179 – 181 # 2008 Wiley-VCH Verlag GmbH&Co. KGaA, Weinheim 179