Study of Characterization and Mechanism of Sugarcane Bagasse made Activated Carbon

Synthesis of activated carbon from sugarcane bagasse is a challenging attitude to produce ecofriendly and efficient bio-adsorbent for pollutant removal. Harvesting and processing of agricultural crops produces significant quantities of residues. It is the most abundant residue producing approximately 100 million tons per annum in Indian context. Proper disposal of agricultural wastes can reduce a serious problem of water pollution. Sugarcane bagasse composed of cellulose (45%), hemicellulose (28%), lignin (20%), sugar (5%), minerals (1%) and ash (2%). Hence, pyrolysis under controlled conditions can transform carbonaceous raw material into carbon rich compounds like AC. Due to high lignocellulosic content, its usefulness in the form of activated carbon is gaining importance. Microporous structure of any AC is due to its high cellulose and low lignin content. Utilization of sugarcane bagasse as a precursor for making activated carbon and its mechanism of activation has been studied in this paper. In this research activated carbon synthesized by using H ₃ PO ₄ and optimum condition of preparation was found to be the ratio 1:1 at 900°C for 1 hr. The prepared activated carbon was named as SB-OPA ₁ -900 representing the raw material, activating agent, ratio and temperature. Based on this condition, mechanism of H ₃ PO ₄ activation is also discussed in this paper. During activation, the lignoellulosic polymeric structures will decomposes, with liberation of non-carbon elements like H, O and N in the form of bitumen (tars) and gases. This will results in development of rigid carbon structure in the form of aromatic sheets and strips. When lignocellulosic components mixed with acid, the H ₃ PO ₄ first attacks the hemicellulose and lignin rather than cellulose as cellulose is more resistant to acid hydrolysis. Due to aggressive action of H ₃ PO _4, lignicellulosic materials started to degrade and occupies a substantial volume. During washing, acid washed out and empty pores will appears in the product. It has been observed during experimentation that when phosphoric acid mixed with the precursor, the temperature of the container increases slowly. This process leads to an extensive liberation of CO /CO ₂ and CH ₄ .