Pyrolysis of switchgrass (Panicum virgatum L.) at low temperatures in N-2 and CO2 environments; a study on chemical composition of chars extracts and bio-oils

作者：Pilon Guillaume; Lavoie Jean Michel^*

来源：Journal of Analytical and Applied Pyrolysis, 2013, 101: 122-131.

DOI：10.1016/j.jaap.2013.02.002

• Pyrolysis
• Char
• Soxhlet extractions
• Dichloromethane
• Bio-oil
• GC-MS

With the increasing value addition applications of biomass pyrolysis char such as a soil amendment or feedstock for subsequent thermochemical conversions, chemical composition of char extracts becomes a necessity. Along this study, switchgrass (Panicum virgatum L) was pyrolyzed using two distinct gas vectors, N-2 VS. CO2, at 300,400 and 500 C for 2.5 min in a 25 g/batch fixed bed reactor using a 55 degrees C/min preheating stage temperature ramp. Chars were extracted with dichloromethane using Soxhlet, and these mixtures, in common with pyrolytic liquids were analyzed by GC-MS. With respect to temperature, the process performed at 500 C resulted in a significantly lesser amount of char extracts as compared to the ones produced at 300 and 400 C respectively. Differences were observed with respect to gas environments at the 3 operating temperatures. Among the differences, the pyrolysis performed at 300 degrees C under CO2 lead to higher char extracts content compared to N2 environment (9 vs. 6 mg/g (char)). Chars obtained at 300 C-CO2 had a significantly lower calorific value compared to those from 300 degrees C-N-2 (22.2 vs. 24.5 Ml/kg respectively). At 400 degrees C, furfural was only found in char extracts from N-2 gas inflow environment, while in bio-oil, it was also found at significantly higher relative content under N-2 VS. CO2. The char extracts as well as condensable chemical compounds have demonstrated predominant levels of phenols, cyclopentanones derivatives and furan-derived compounds.

• 出版日期2013-5