Pantnagar Journal of Research

Abstract

TThis study investigates the impact of four biomass materials—pine cone, paddy straw, coconut shell and pine needle on the yield and quality of activated biochar. Biomass was characterized for composition, proximate and ultimate properties. The chemical activation process was performed using phosphoric acid (H_₃PO_₄) under varying conditions of activation time (20, 40 and 60 minutes), temperature (400^°C, 450^°C and 500^°C), and impregnation ratio (1:1.25, 1:1.5 and 1:1.75). Results showed that coconut shell produced the highest biochar yield, ranging from 65.23% to 48.77%, followed by pine needle (47.39% 57.81%) and pine cone (52.75%–45.23%). Paddy straw exhibited the lowest yield, from 39.6% to 33.72%. Biomass with higher carbon content and lignin, such as coconut shell, produced higher biochar yields, while materials with lower lignin, like pine cone and paddy straw, had lower yields. Longer activation times and higher temperatures reduced biochar yield by promoting volatile production. Surface area and porosity analysis indicated that coconut shell and pine needle biochar had the highest surface areas, beneficial for adsorption. The study demonstrates that phosphoric acid activation is an effective, cost-efficient method for producing biochar with desirable properties for environmental applications like water treatment, soil amendment and air purification