Preparation of Highly Porous Activated Carbon With High Specific Surface Area From Agricultural Wastes

Kazakhstan annually generates a significant amount of agro-industrial waste, which, due to the high content of carbonaceous compounds, can potentially become a valuable raw material for the production of activated carbon. This research considers the processing of rice husks from Kyzylorda region, as well as soya and sunflower husks from East Kazakhstan into activated carbon. Potassium hydroxide (KOH) was used for activation to achieve high specific surface area. The optimal activation conditions were determined to be 750°C for 150 minutes with 1:4 (agro waste : KOH). The obtained activated carbon samples from rice husk, soybean husk and sunflower husk were characterised by BET, SEM, XRD, energy dispersive analysis, TGA and DSC. The synthesised activated carbons possessed a developed porous structure with specific surface area: 2363.7 m ² /g (RH), 786.1 m ² /g (SfH), 642.4 m ² /g (SBH), which was confirmed by the above analyses. These findings highlight the potential of agro-industrial waste as a sustainable source for high-performance activated carbon production.