View Artide Online Review Article Chem Soc Rev growth of about 1.6%(Table D1 in the reference).2Despite the and therefore has been identified as scalable,economically large variety of new energy carriers,liquid hydrocarbon still viable,and potentially carbon neutral feedstock for the production appears to be the most attractive and feasible form of trans- of renewable biofuels via appropriate technologies.Biochemical portation fuel,including aviation fuel.3 The U.S.renewable fuels conversion methodologies proposed for lignocelluloses await cost- standard(RFS2)requires an increase in the domestic supply of effective technologies5 and can only process cellulosic and alternative fuels to 36 billion gallons by 2022,including 15 billion hemicellulosic portions of lignocellulosic biomass.However, gallons from corn-based ethanol and 21 billion gallons of the thermochemical conversion routes are more energy efficient,' advanced biofuels from lignocellulosic biomass.The U.S.Energy and more flexible in terms of feed and products.s Among the Information Administration projects that the production of primary thermochemical conversion routes (i.e.,gasification and liquid fuels from biomass will soar in the next 30 years irrespec- fast pyrolysis),fast pyrolysis is the most economically feasible way tive of whether the oil prices are low or high(Fig.59 in ref.4).to convert biomass into liquid fuels,and has therefore attracted New technologies must be developed for the efficient conversion a great deal of research over the past two decades.A techno- of biomass to fuels that have high energy density and compat- economic analysis of three conversion platforms (ie.,pyrolysis, ibility with the existing energy infrastructure.3 gasification,and biochemical)comparing capital and operating Lignocellulosic biomass(such as wood,grass,and agricul- costs for near-term biomass-to-liquid fuels technology scenarios tural waste)is the most abundant and cheapest carbon source was performed recently.The analysis showed that the stand- alone biomass-to-liquid fuel plants are expected to produce fuels with a product value in the range of $2.00-5.50 per gallon gasoline equivalent,with fast pyrolysis being the lowest,and Ayman M.Karim is currently a bio-chemical conversion the highest.Fast pyrolysis shows the senior research scientist at Pacific highest yield to liquid fuel products and retains most of the Northwest National Laboratory energy from feedstocks in the liquid products.-11 Biomass (PNNL).Prior to joining PNNL conversion via fast pyrolysis is also on the verge of commercia- he did a postdoctoral stay lization.2 For instance,Envergent (a joint venture between (2007-2008)with Prof.Dionisios UOP/Honeywell and Ensyn)has a pilot-scale demonstration G.Vlachos at the University of plant under construction in Hawaii for biomass conversion to Delaware.He obtained his PhD fuels via fast pyrolysis.3 in chemical engineering from the The primary liquid product of fast pyrolysis of biomass is University of New Mexico (2007) generally called bio-oil,which is obtained by immediately under the guidance of Prof.quenching the pyrolysis vapors.Bio-oils are composed of a Abhaya K.Datye.His current large variety of condensable chemicals derived from many Ayman M.Karim research interests include funda- simultaneous and sequential reactions during the pyrolysis of mental studies of colloidal nano-lignocellulosic biomass.Bio-oil is a highly complex mixture of particles synthesis mechanisms,in situ and in operando catalyst more than 300 oxygenated compounds.10.14.5 characterization by X-ray absorption spectroscopy and developing Typical bio-oil from fast pyrolysis of woody biomass has a novel catalytic materials for the synthesis of fuels and chemicals high oxygen content and a low H/C ratio compared to crude oil from biomass. (Table 1).The chemical composition classified by functional Junming Sun is an assistant Yong Wang joined Pacific research major professor in Northwest National Laboratory Prof.Yong Wang's group at (PNNL),USA,in 1994 and was Washington State University, promoted to Laboratory Fellow in USA.He received his PhD from 2005.In 2009,he assumed a joint Dalian Institute of Chemical position at Washington State Physics of Chinese Academy of University (WSU)and PNNL.In Science in 2007 (Prof.Xinhe Bao), this unique position,he continues after which he worked with Prof. to be a Laboratory Fellow at PNNL Bruce C.Gates at UC Davis and is the Voiland Distinguished (2007-2008)and then with Prof. Professor in Chemical Engineering Yong Wang at Pacific Northwest at WSU,a full professorship with Junming Sun National Laboratory(2008-2011) Yong Wang tenure.His research interests as a postdoc researcher.His include the development of novel current research interests include fundamental understanding and catalytic materials and reaction engineering for the conversion of rational design of acid-base/supported metal catalysts for biomass fossil and biomass feedstocks to fuels and chemicals. derived small oxygenates,bimetallic catalysis for hydrodeoxygenation. This joumnal is The Royal Society of Chemistry 2014 Chem.Soc.Rev.2014.43.7594-762317595This journal is © The Royal Society of Chemistry 2014 Chem. Soc. Rev., 2014, 43, 7594--7623 | 7595 growth of about 1.6% (Table D1 in the reference).2 Despite the large variety of new energy carriers, liquid hydrocarbon still appears to be the most attractive and feasible form of trans￾portation fuel, including aviation fuel.3 The U.S. renewable fuels standard (RFS2) requires an increase in the domestic supply of alternative fuels to 36 billion gallons by 2022, including 15 billion gallons from corn-based ethanol and 21 billion gallons of advanced biofuels from lignocellulosic biomass. The U.S. Energy Information Administration projects that the production of liquid fuels from biomass will soar in the next 30 years irrespec￾tive of whether the oil prices are low or high (Fig. 59 in ref. 4). New technologies must be developed for the efficient conversion of biomass to fuels that have high energy density and compat￾ibility with the existing energy infrastructure.5 Lignocellulosic biomass (such as wood, grass, and agricul￾tural waste) is the most abundant and cheapest carbon source and therefore has been identified as scalable, economically viable, and potentially carbon neutral feedstock for the production of renewable biofuels via appropriate technologies. Biochemical conversion methodologies proposed for lignocelluloses await cost￾effective technologies6 and can only process cellulosic and hemicellulosic portions of lignocellulosic biomass. However, the thermochemical conversion routes are more energy efficient,7 and more flexible in terms of feed and products.8 Among the primary thermochemical conversion routes (i.e., gasification and fast pyrolysis), fast pyrolysis is the most economically feasible way to convert biomass into liquid fuels,6 and has therefore attracted a great deal of research over the past two decades. A techno￾economic analysis of three conversion platforms (i.e., pyrolysis, gasification, and biochemical) comparing capital and operating costs for near-term biomass-to-liquid fuels technology scenarios was performed recently. The analysis showed that the stand￾alone biomass-to-liquid fuel plants are expected to produce fuels with a product value in the range of $2.00–5.50 per gallon gasoline equivalent, with fast pyrolysis being the lowest, and bio-chemical conversion the highest.6 Fast pyrolysis shows the highest yield to liquid fuel products and retains most of the energy from feedstocks in the liquid products.9–11 Biomass conversion via fast pyrolysis is also on the verge of commercia￾lization.12 For instance, Envergent (a joint venture between UOP/Honeywell and Ensyn) has a pilot-scale demonstration plant under construction in Hawaii for biomass conversion to fuels via fast pyrolysis.13 The primary liquid product of fast pyrolysis of biomass is generally called bio-oil, which is obtained by immediately quenching the pyrolysis vapors. Bio-oils are composed of a large variety of condensable chemicals derived from many simultaneous and sequential reactions during the pyrolysis of lignocellulosic biomass. Bio-oil is a highly complex mixture of more than 300 oxygenated compounds.10,14,15 Typical bio-oil from fast pyrolysis of woody biomass has a high oxygen content and a low H/C ratio compared to crude oil (Table 1). The chemical composition classified by functional Junming Sun Junming Sun is an assistant research & major professor in Prof. Yong Wang’s group at Washington State University, USA. He received his PhD from Dalian Institute of Chemical Physics of Chinese Academy of Science in 2007 (Prof. Xinhe Bao), after which he worked with Prof. Bruce C. Gates at UC Davis (2007–2008) and then with Prof. Yong Wang at Pacific Northwest National Laboratory (2008–2011) as a postdoc researcher. His current research interests include fundamental understanding and rational design of acid–base/supported metal catalysts for biomass derived small oxygenates, bimetallic catalysis for hydrodeoxygenation. Yong Wang Yong Wang joined Pacific Northwest National Laboratory (PNNL), USA, in 1994 and was promoted to Laboratory Fellow in 2005. In 2009, he assumed a joint position at Washington State University (WSU) and PNNL. In this unique position, he continues to be a Laboratory Fellow at PNNL and is the Voiland Distinguished Professor in Chemical Engineering at WSU, a full professorship with tenure. His research interests include the development of novel catalytic materials and reaction engineering for the conversion of fossil and biomass feedstocks to fuels and chemicals. Ayman M. Karim Ayman M. Karim is currently a senior research scientist at Pacific Northwest National Laboratory (PNNL). Prior to joining PNNL he did a postdoctoral stay (2007–2008) with Prof. Dionisios G. Vlachos at the University of Delaware. He obtained his PhD in chemical engineering from the University of New Mexico (2007) under the guidance of Prof. Abhaya K. Datye. His current research interests include funda￾mental studies of colloidal nano￾particles synthesis mechanisms, in situ and in operando catalyst characterization by X-ray absorption spectroscopy and developing novel catalytic materials for the synthesis of fuels and chemicals from biomass. Review Article Chem Soc Rev Published on 07 May 2014. Downloaded by Shanghai Jiaotong University on 18/02/2016 07:32:58. View Article Online