(250e) A Comparative Study of Different Analytical Methods in Quantifying the Sugar Compositions of Bio-Oil

Xianglan Bai^{1, 5}, Alex Liu^{2, 5}, Kwang Ho Kim^{3, 5} and Robert C. Brown ^{4, 5}

1. Department of Aerospace Engineering

2. Department of Chemical Engineering

3. Department of Agricultural and Biosystem Engineering

4. Department of Mechanical Engineering

5. Center for Sustainable Environmental Technologies

Iowa State University, Ames, IA 50010

GC/MS (or FID) is an analytic technique widely used to quantify the compositions of bio-oil that produced from the pyrolysis of biomass.  In GC/MS, the temperature of GC column is gradually ramped up from room temperature to an elevated temperature (230 ºC -300ºC) and the chemical compounds of bio-oil are separated based on the differences of the evaporation temperature for each compound.  However, certain compounds in bio-oil are thermally instable and may polymerize or degrade at the high temperature levels, which may cause uncertainties in the quantification results.  For example, levoglucosan in liquid phase can polymerize at an elevated temperature.  Recently, a new technique was developed in our group to quantify the sugar compositions of bio-oil using HPLC.  With this new method, the sample temperature is kept at 75ºC during the whole analysis process to prevent levoglucosan from polymerizing. In the present study, the sugar yields in the same bio-oil are quantified by using the two analytic methods in order to evaluate the influence of analytical methods on the quantification of the sugar compositions in bio-oil.