Single step preparation of activated biocarbons derived from pomegranate peels and their CO2 adsorption performance

Abstract

In this work, pomegranate peel (PP), the by-products abundantly available from the fruit processing industries, has been applied as renewable resources for preparation of low cost, eco-friendly and high quality activated carbons. The optimum conditions for the adsorption of carbon dioxide (CO2) by the activated carbons were evaluated by controlling the activation temperature. KOH was used as the activation agent at a KOH/PP activation ratio of 1:1. Four activated carbons were synthesized at activation temperatures in the range 600−900 °C, their surface and pore characteristics along with the CO2 adsorption were examined. The results showed that with the increase in activation temperature from 600 to 800 °C, the total pore volume and specific surface area sharply increased from 0.78 to 1.28 cm3/g and 1311 to 2141 m2/g, respectively. However, the values for both these parameters decreased at temperatures above 900 °C. The best CO2 adsorption capacity of 4.44 mmol/g and 5.53 mmol/g were obtained for the PP-K-800 sample at 25 and 0 °C up to 1 bar, respectively. This result highlights the importance of the structural and textural characteristics of the activated carbon, prepared at different activation temperatures on CO2 adsorption behaviors.