Production and characterization of bio oil and bio char from flax seed residue obtained from supercritical fluid extraction industry

Fast pyrolysis of the flax seed residue was carried out in a semi-batch reactor with an aim to study the product distribution and to identify optimum temperature condition for maximizing the bio-oil yield. The effect of temperature on product distribution, elemental composition, and physical properties of major products of pyrolysis such as bio oil and bio char was investigated. The maximum condensable fraction yield was found to be 50.66 wt% at a pyrolysis temperature of 500 °C, out of which the amount of bio-oil excluding the aqueous layer was 31 wt.%. The chemical composition of bio-oil obtained at optimum condition is analyzed using CHNS analyzer, FTIR and GC-MS. Fuel properties are also determined using IS methods. The bio oil was found to have higher calorific value than the feedstock. Again, it was found slightly basic in nature owing to the presence of higher concentration of basic components than acidic components. The char was characterized for elemental composition, heating value and surface area.