Pyrolysis of Miscanthus and characterization of value-added bio-oil and biochar products

Miscanthus, an invasive crop, has recently gained attention as an emerging energy crop because of certain traits like fast growth, high yield, ability to grow in marginal land, and resistance to extreme weather conditions. In this work, Miscanthus was selected as the feedstock for fast pyrolysis in a mechanically fluidized bed reactor at variable temperatures (400 degrees C, 450 degrees C, and 500 degrees C) and vapour residence times (1.4, 2.7, and 5.2 seconds). Fast pyrolysis performed at 450 degrees C with 1.4 seconds of vapour residence time gave the highest yield of bio-oil (>50 wt%). Biochar obtained at different pyrolysis temperatures was activated at 900 degrees C for 1.5 hours under CO2 atmosphere to enhance its value as a potential adsorption agent for pollutants. Several physicochemical characterization techniques were used to study the bio-oils, biochars, and activated biochars obtained from the pyrolysis of Miscanthus. The absorption of methylene blue as a model dye was done to evaluate the performance of activated biochar vs the biochar precursors. Both pyrolysis and physical activation complemented each other as new technologies for energy extraction and material synthesis from Miscanthus.