FTIR as a simple tool to quantify unconverted lignin from chars in biomass liquefaction process: Application to SC ethanol liquefaction of pine wood

Abstract Lignin in solid residues produced from wood liquefaction can be quantified by FTIR analysis. This is applied to investigate pine wood liquefaction in supercritical ethanol in comparison with model lignin and cellulose in order to achieve a thorough description of wood liquefaction in SC ethanol. The proportions of lignin, hemicelluloses, cellulose and chars in the solid residue were quantified by compositional analysis based on acid hydrolysis combined to the quantitative FTIR analysis of the νC C vibration of lignin at 1514 cm− 1. It was shown that SC ethanol is an efficient medium for an easy liquefaction of lignin and hemicellulose from pine wood. Native cellulose in pine wood was only slightly attacked by contrast to microcrystalline cellulose. From pine wood, gas production is limited to 3 wt.% and total yields in liquid products achieved 45 wt.% but only one fourth of liquid products were eluted by GC–MS.

[1]  M. Bardet,et al.  Two-dimensional spin-exchange solid-state NMR studies of 13 C-enriched wood. , 1997, Solid state nuclear magnetic resonance.

[2]  Mathew Leitch,et al.  Highly Efficient Liquefaction of Woody Biomass in Hot-Compressed Alcohol−Water Co-solvents† , 2010 .

[3]  J. Thibault,et al.  Fourier transform infrared spectrometry and thermogravimetry of partially converted lignocellulosic materials , 1987 .

[4]  A. Piccolo,et al.  Physical–chemical characteristics of lignins separated from biomasses for second-generation ethanol , 2014 .

[5]  Allan Gilbert,et al.  Production of bio‐crude from forestry waste by hydro‐liquefaction in sub‐/super‐critical methanol , 2009 .

[6]  G. Zeng,et al.  Thermochemical liquefaction of rice husk for bio-oil production with sub- and supercritical ethanol as solvent , 2013 .

[7]  C. Popescu,et al.  Structural modifications of Tilia cordata wood during heat treatment investigated by FT-IR and 2D IR correlation spectroscopy , 2013 .

[8]  A. Quignard,et al.  A Short Historical Review of Fast Pyrolysis of Biomass , 2013 .

[9]  P. Patil,et al.  Heterogeneously Catalyzed Hydroprocessing of Organosolv Lignin in Sub- and Supercritical Solvents , 2011 .

[10]  U. Kim,et al.  Investigation of structural modification and thermal characteristics of lignin after heat treatment. , 2014, International journal of biological macromolecules.

[11]  S. Saka,et al.  Liquefaction of beech wood in various supercritical alcohols , 2006, Journal of Wood Science.

[12]  R. Sun,et al.  Sequential extractions and structural characterization of lignin with ethanol and alkali from bamboo (Neosinocalamus affinis) , 2012 .

[13]  M. Küçük,et al.  Liquefaction of sunflower stalk by using supercritical extraction , 1998 .

[14]  Daniel Pasquini,et al.  Extraction of lignin from sugar cane bagasse and Pinus taeda wood chips using ethanol-water mixtures and carbon dioxide at high pressures , 2005 .

[15]  Amie D. Sluiter,et al.  Determination of Structural Carbohydrates and Lignin in Biomass , 2004 .

[16]  Wei Zhao,et al.  Molecular composition of soluble fraction from depolymerized cornstalk powder in supercritical methanol and ethanol. , 2010 .

[17]  Pattarapan Prasassarakich,et al.  Bio-Oil from Hydro-Liquefaction of Bagasse in Supercritical Ethanol , 2010 .

[18]  C. Xu,et al.  Hydrolytic degradation of alkaline lignin in hot-compressed water and ethanol. , 2010, Bioresource technology.

[19]  O. Kajimoto.  Solvation in Supercritical Fluids: Its Effects on Energy Transfer and Chemical Reactions. , 1999, Chemical reviews.

[20]  C. Xu,et al.  Hydro-liquefaction of woody biomass in sub- and super-critical ethanol with iron-based catalysts , 2008 .

[21]  S. Saka,et al.  Comparison of the decomposition behaviors of hardwood and softwood in supercritical methanol , 2003, Journal of Wood Science.

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

[23]  N. Essayem,et al.  Cellulose Reactivity in Supercritical Methanol in the Presence of Solid Acid Catalysts: Direct Synthesis of Methyl-levulinate , 2011 .

[24]  Y. Matsumura,et al.  Gasification Rate of Various Biomass Feedstocks in Supercritical Water , 2013 .

[25]  H. Pereira,et al.  Determination of Lignin Content of Eucalyptus globulus Wood Using FTIR Spectroscopy , 1998 .

[26]  Ben J. McCoy,et al.  Extraction of lignin from wood with supercritical alcohols , 1989 .