Slow pyrolysis of cystoseira barbata brown macroalgae

Abstract

Slow pyrolysis of algal biomass of Cystoseira barbata was performed in a fixed bed reactor using carbon dioxide as a sweeping gas and a reactant in the process. Pyrolysis products consisted of a biochar, a bio-oil, and pyrolytic gases. According to a 23 factorial experiment, 8 tests were conducted for 1 hr at two levels of each process factor, i.e., specific heat flow rate (7540, 9215 W/m3), carbon dioxide superficial velocity (1.3, 2.6 cm/s), and bulk density of fixed bed biomass (221, 332 kg/m3). Correlations between these factors and final process responses in terms of mean bed temperature (461-663 oC), biochar yield (15.2-26.7%), bio-oil yield (29.9-34.8%), and BET surface area of biochar (45.17-91.12 m2/g) were established.