Obtaining activated biochar from olive stone using a bench scale high-pressure thermobalance

A low cost-biomass, olive stone, was used as a carbon precursor to synthesize activated biochar. Experiments were carried by single step activation for two agents (steam and CO2) using bench scale high-pressure thermobalance. Temperature, pressure, flow rate holding time optimized according the highest adsorption capacity of biochar obtained. In this respect, conditions established at 900 °C 30 min, 0.15 ml/min 1 bar H2O activation. The optimum CO2 found be 1000 300 bar. biochars yielded characterized adsorption-desorption N2 ?196 °C, scanning electron microscopy, Raman spectroscopy, thermogravimetric analyses elemental analyses. Results showed that only generated microporosity developed in biochar, whereas both meso micropores created after steam Then, materials evaluated possible adsorbent purpose, isotherms over pressure range 1–20 studied. Moreover, results these fitted Langmuir, Freundlich Sips isotherm models, latter forecast most accurately.