Production and Evaluation of Physicochemical Characteristics of Paddy Husk Bio-char for its C Sequestration Applications

Bio-char is a carbon-rich solid material generated by thermochemical conversion process (pyrolysis) of lignocellulosic biomass, and its viability as a sustainable material has received increasing attention for environmental remediation. The relationship between bio-char properties and its applicability as a soil amendment is still not conclusive. The purpose of this research is to study the bio-char physical and chemical properties from an agricultural residue to examine the quality criteria for carbon sequestration and agricultural uses. Pyrolysis temperature was shown to have a strong impact on production and characteristics of bio-char samples. The bio-char yield decreased with increasing temperatures (350-550 A degrees C). According to proximate and ultimate analysis data, temperature has the strongest impact on carbon stability of bio-char (stability increased at higher temperature). The volatile matter decreased while fixed carbon content increased with the increase of pyrolysis temperature. To evaluate further bio-char quality, the relationships between (O/C and H/C molar ratio) and (H/C and volatile matter) of raw paddy husk and produced bio-char at various temperatures is proposed. SEM, FT-IR, and C-13 NMR findings are in well agreement with thermogravimetric and proximate analysis of the bio-char that structural and physicochemical properties were significantly influenced by pyrolysis temperature. CO2 adsorption rate increased with increasing temperature. Bio-char produced at 450 A degrees C showed higher absorption capability and could be a potential sustainable substrate for C sequestration and soil amendment.