Synthesis and study of the porous structure of biochars obtained from crustacean waste

Biochar samples from crustacean processing waste were synthesized by carbonization followed by alkaline activation. The influence of synthesis parameters (time, temperature) on the porous structure of biochar was considered. The results showed that biomass carbonization conditions significantly affect the final porosity parameters. It was found that the biochar samples obtained by varying the synthesis parameters were micromesoporous. Temperature was shown to be the main influencing factor during biomass carbonization. At a three-hour carbonization duration and a temperature of 650 °C, the specific surface area (2708 m²×g^–1) and pore volume (total pore – 1.58 cm³×g^–1, micropore – 0.64 cm³×g^–1, mesopore – 0.94 cm³×g^–1) in the obtained biochar reached their maximum values. Methane adsorption on the obtained biochar was studied at ambient temperature and pressure up to 100 bar. Biochar obtained from crustacean waste was shown to exhibit a high methane adsorption capacity of ~18 mmol×g^–1. Experimental adsorption data were analyzed using the Langmuir, Freundlich, and Dubinin-Radushkevich models. The influence of synthesis parameters on the pore structure of biochars, as well as the adsorption data evaluated in the study, are useful for designing adsorption systems.

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