Effect of pre-hydrolysis and salt- impregnation on biochar production from jute stick

This work investigates the effects of pre-hydrolysis and salt impregnation (ZnCl₂ and ZnSO₄) on synthesizing biochar from jute sticks. The jute stick and prepared biochar were characterized by evaluating the thermal stability, surface chemistry, and surface morphology. Our analysis revealed that pre-hydrolyzed and raw jute sticks had higher decomposition rates than salt-impregnated ones after 300 °C, thus leading to a higher yield for the salt-impregnated jute stick. Spectroscopic analysis of pretreated jute stick biochar showed the evolution of new functional groups during conversion, while many functional groups were eliminated. Based on the surface characteristics of biochar examined by SEM and BET, pre-hydrolyzed jute stick biochar displayed the highest porosity (Langmuir surface area of ~149.48 m²/g). Finally, the proximate analysis showed that the optimum temperature for producing jute stick biochar was 320 °C with combined pretreatment of pre-hydrolysis and salt impregnation producing a yield of 49% and a fixed carbon content of 83%. (Figure presented.)