(137b) Quantification of Biomass Pyrolysis Products Using GC-MS/PA-FID Analysis

This study seeks to identify and quantify biomass pyrolysis products in tangent through the use of dual gas chromatography (GC) detectors. The GC uses mass spectrometry (MS) to identify components in the biomass product and a flame ionization detector (FID) coupled with a Polyarc (PA) methanation reactor to readily quantify carbon present in each sample. The PA reactor converts every carbon atom present in each compound to methane prior to reaching the FID; therefore, the FID response factors for each compound are the same and only one calibration standard is needed to quantify the entire range of bio-oil products. There are limitations on what types of products can be detected by the GC, including non-volatiles, high molecular weights, highly polar compounds, etc. The GC-MS/PA-FID sheds light on what percentage of products are not analyzed by the GC and allows for reporting of absolute rather than relative product amounts.

A 2.5” fluidized bed reactor was used to pyrolyze a loblolly pine feedstock at temperatures from 450 – 500 C. Both organic and aqueous liquid biomass pyrolysis products were collected and analyzed using the GC-MS/PA-FID system. Each detectable compound present in the sample was identified, and the mass of carbon in each detectable compound was determined. The sum of carbon in all compounds gives the total detected carbon in the bio-oil product. The total carbon present in each collected sample was measured from CHN elemental analysis; therefore, the percent of carbon analyzed can be found. Carbon balances of different bio-oil samples were analyzed at various reaction conditions and correlated to the water content in the samples. Trends between sample composition and carbon analyzed were observed and have led to greater insight into biomass pyrolysis products.