Effect of Activating Agents on the Production of Activated Carbon from Rice Husk

The used of activated carbon cannot be over emphasize; this is why production from locally agricultural biomass attract much attention in the field of material science and technology as this also contribute in reducing agricultural wastes from the environment. The aim of this project is to compare the effectiveness of different activating agents in the production of activated carbon (an adsorbent) from rice husk. Three different reagents were used in the preparation of the adsorbent, Zinc chloride, Sulphuric acid and phosphoric acid. The surface area of the adsorbent prepared using zinc chloride as an activating agent was found to be 551 m2/g, its ash content was 20%, pH 8.04, moisture content 36.00%, volatile matter 16.67% and fixed carbon 27.33%. While surface area of the adsorbent prepared using Sulphuric acid as an activating agent was found to be 647 m2/g its ash content was 16.06%, pH 5.17, moisture content 37.00%, volatile matter 28.17% and fixed carbon 18.77%. However, the surface area of adsorbent prepared using phosphoric acid as an activating agent was found to be 743 m2/g, ash content 11%, pH 5.32, moisture content 38.71%, volatile matter 32.68% and fixed carbon 17.61%. Thus, among the three different activating agents, phosphoric acid was found to give adsorbent with the largest specific surface area of 734 m2/g, indicating that, it is the most effective among the three activating agents in producing highly porous activated carbon.