Quantitative GC-MS Analysis of Sawdust Bio-Oil

Abstract

Bio-oils from biomass pyrolysis have a highly promising potential as biofuels or sources of chemicals. The quantitative analysis of bio-oils is quite difficult and requires many standards. In this study, we developed a methodology using only 16 standards for determining the concentration of 49 compounds, representatives of the main chemical classes commons in bio-oils, using relative response factors (RRF) and analytical curves. Five Pinus sawdust bio-oils were analyzed using a GC-MS-DB-5 capillary column (60 m). SCAN mode (from 45 to 450 Daltons) and retention indices (LPTRI) were used for qualitative analysis. For quantitative analysis, SIM mode was preferred, and analytical curves were constructed from an initial solution at 400 mg g-1 of each of the 16 standards, with concentrations ranging from 1 to 150 mg g-1 added to the internal standard (methyl hexanoate) at 70 mg g-1. After the positive identification and quantification of 9 compounds (among the 16 standards used), the other compounds were quantified using the RRF obtained from a standard solution at 30 mg g-1, considering the similarities with those identified standards. 196 compounds were identified, while 49 compounds were quantified, highlighting the monoaromatic hydrocarbons, naphthalenes, benzofurans, alkyl phenols, and catechols.