Hydrothermal liquefaction of cellulose to bio-oil under acidic, neutral and alkaline conditions

Hydrothermal liquefaction (HTL) of biomass to bio-oil under alkaline or neutral conditions has been widely reported in literature. However, there has been limited data available in literature on comparing HTL of biomass to bio-oil under acidic, neutral, and alkaline in terms of chemical compositions and yields by using the same reaction conditions and reactor. Using cellulose as a feedstock we conducted the comparative studies for pH=3, 7 and 14 at temperatures of 275–320°C with reaction residence times of 0–30min. Results showed that the chemical compositions of the bio-oils were different for acidic, neutral and alkaline conditions. Under acidic and neutral conditions, the main composition of HTL bio-oil was 5-(Hydroxymethyl)furfural (HMF). Under alkaline conditions, the main compounds became C2–5 carboxylic acids. For bio-oil yields, it was observed that high temperatures and long residence times had negative effects, regardless of the pH levels. However, the corresponding reaction mechanisms are different. Under acidic conditions, the decrease in the bio-oil yields was mainly caused by polymerization of 5-HMF to solids. Under neutral conditions, the bio-oil yields decreased because 5-HMF was converted to both solid and gaseous products. Under alkaline conditions, the bio-oil decomposed to gases through the formation of short chain acids and aldehydes. Therefore, although they were all referred to as HTL bio-oil in literature, they were formed by different reaction pathways and had different properties due to their different chemical compositions. Given these differences, different strategies are recommended in this study to further improve HTL of biomass to bio-oil.

[1]  Z. Tan,et al.  Hydrothermal Conversion of Cellulose to 5-Hydroxymethyl Furfural , 2011 .

[2]  I. Ardi̇c,et al.  Identification of the compounds in the aqueous phases from liquefaction of lignocellulosics , 2005 .

[3]  M. Fatih Demirbas,et al.  Biorefineries for biofuel upgrading: A critical review , 2009 .

[4]  Yuanhui Zhang,et al.  THERMOCHEMICAL CONVERSION OF SWINE MANURE: AN ALTERNATIVE PROCESS FOR WASTE TREATMENT AND RENEWABLE ENERGY PRODUCTION , 2000 .

[5]  Ryan Dolan,et al.  Subcritical hydrothermal liquefaction of cattle manure to bio-oil: Effects of conversion parameters on bio-oil yield and characterization of bio-oil. , 2010, Bioresource technology.

[6]  S. Bhatia,et al.  Subcritical water liquefaction of oil palm fruit press fiber in the presence of sodium hydroxide: an optimisation study using response surface methodology. , 2010, Bioresource technology.

[7]  Y. Matsumura,et al.  Formation of Tarry Material from 5-HMF in Subcritical and Supercritical Water , 2009 .

[8]  Ayhan Demirbas,et al.  Yields of oil products from thermochemical biomass conversion processes , 1998 .

[9]  Ayhan Demirbas,et al.  Use of algae as biofuel sources. , 2010 .

[10]  Tomoaki Minowa,et al.  Biomass gasification in near- and super-critical water: Status and prospects , 2005 .

[11]  Z. Tan,et al.  Alkaline hydrothermal conversion of cellulose to bio-oil: influence of alkalinity on reaction pathway change. , 2011, Bioresource technology.

[12]  T. Ogi,et al.  Liquid fuel production from sewage sludge by catalytic conversion using sodium carbonate , 1987 .

[13]  Morgan Fröling,et al.  Thermochemical biofuel production in hydrothermal media: A review of sub- and supercritical water technologies , 2008 .

[14]  C. Xu,et al.  Production of Heavy Oils with High Caloric Values by Direct Liquefaction of Woody Biomass in Sub/Near-critical Water , 2008 .

[15]  Paul T. Williams,et al.  Role of sodium hydroxide in the production of hydrogen gas from the hydrothermal gasification of biomass , 2009 .

[16]  G. N. Richards,et al.  Mechanism of formation of 5-(hydroxymethyl)-2-furaldehyde from D-fructose an sucrose. , 1990, Carbohydrate research.

[17]  Yuanhui Zhang,et al.  EFFECTS OF FEEDSTOCK pH, INITIAL CO ADDITION, AND TOTAL SOLIDS CONTENT ON THE THERMOCHEMICAL CONVERSION PROCESS OF SWINE MANURE , 2001 .

[18]  Kunio Arai,et al.  Reactions of D-fructose in water at temperatures up to 400 °C and pressures up to 100 MPa , 2007 .

[19]  Janusz A. Kozinski,et al.  Liquefaction and gasification of cellulose with Na2CO3 and Ni in subcritical water at 350 °C , 2004 .

[20]  Markus Antonietti,et al.  Hydrothermal carbon from biomass : a comparison of the local structure from poly- to monosaccharides and pentoses/hexoses. , 2008 .

[21]  Kunio Arai,et al.  Dehydration Of D-glucose in high temperature water at pressures up to 80 MPa , 2007 .

[22]  Yutaka Dote,et al.  Oil production from garbage by thermochemical liquefaction , 1995 .

[23]  S. Bhatia,et al.  Subcritical water liquefaction of oil palm fruit press fiber for the production of bio-oil: effect of catalysts. , 2010, Bioresource technology.

[24]  O. Bobleter,et al.  Hydrothermal degradation of polymers derived from plants , 1994 .

[25]  Markus Antonietti,et al.  Structural Characterization of Hydrothermal Carbon Spheres by Advanced Solid-State MAS C-13 NMR Investigations , 2009 .

[26]  Z. Tan,et al.  Effects of headspace fraction and aqueous alkalinity on subcritical hydrothermal gasification of cellulose , 2010 .

[27]  A. Gawlik,et al.  Biomass Conversion in Water at 330−410 °C and 30−50 MPa. Identification of Key Compounds for Indicating Different Chemical Reaction Pathways , 2003 .

[28]  Thallada Bhaskar,et al.  Catalytic hydrothermal treatment of pine wood biomass: effect of RbOH and CsOH on product distribution , 2005 .

[29]  Ayhan Demirbas,et al.  Competitive liquid biofuels from biomass , 2011 .

[30]  Abolghasem Shahbazi,et al.  Hydrothermal pyrolysis of swine manure to bio-oil: Effects of operating parameters on products yield and characterization of bio-oil , 2010 .

[31]  Chun-Zhu Li,et al.  Investigation of deactivation mechanisms of a solid acid catalyst during esterification of the bio-oils from mallee biomass , 2013 .

[32]  Y. Matsumura,et al.  Behavior of 5-HMF in Subcritical and Supercritical Water , 2008 .

[33]  L. Rosendahl,et al.  Hydrothermal liquefaction of biomass: A review of subcritical water technologies , 2011 .

[34]  Liejin Guo,et al.  Hydrogen production by biomass gasification in supercritical water: A systematic experimental and analytical study , 2007 .

[35]  Shicheng Zhang,et al.  Hydrothermal Liquefaction of Macroalgae Enteromorpha prolifera to Bio-oil , 2010 .

[36]  Fangming Jin,et al.  Acid catalytic hydrothermal conversion of carbohydrate biomass into useful substances , 2008 .

[37]  Jianhui He,et al.  Structural analysis of bio-oils from sub-and supercritical water liquefaction of woody biomass , 2007 .

[38]  Herman van Bekkum,et al.  Hydrothermal formation of 1,2,4-benzenetriol from 5-hydroxymethyl-2-furaldehyde and d-fructose , 1993 .

[39]  Kunio Arai,et al.  Glucose and fructose decomposition in subcritical and supercritical water: Detailed reaction pathway, mechanisms, and kinetics , 1999 .