To optimize the efficiency of activated carbon in adsorbing pollutants from water, we can manipulate its pore size and surface area through the following methods:1. Selection of precursor materials: The choice of precursor materials used to produce activated carbon plays a significant role in determining its pore size and surface area. Precursors with high carbon content and well-developed porous structures, such as coconut shells, wood, and coal, can result in activated carbons with higher surface areas and more suitable pore size distributions.2. Activation process: The activation process involves heating the precursor material in the presence of an activating agent, such as steam, carbon dioxide, or certain chemicals like phosphoric acid or potassium hydroxide. By controlling the activation temperature, time, and the type and concentration of the activating agent, we can influence the pore size and surface area of the activated carbon. Higher activation temperatures and longer activation times generally result in larger pore sizes and higher surface areas.3. Chemical activation: In chemical activation, the precursor material is impregnated with a chemical activating agent before being heated. This method can create a more uniform pore size distribution and higher surface areas compared to physical activation using steam or carbon dioxide . The choice of the chemical activating agent and its concentration can be adjusted to optimize the pore size and surface area of the activated carbon.4. Post-treatment: After the activation process, the activated carbon can be subjected to post-treatment processes such as acid washing, alkaline treatment, or impregnation with metal ions. These treatments can further modify the pore size distribution and surface area of the activated carbon, enhancing its adsorption capacity for specific pollutants.5. Pore size distribution: To optimize the efficiency of activated carbon for adsorbing pollutants from water, it is essential to have a suitable pore size distribution. Activated carbon with a mix of micropores diameter < 2 nm , mesopores diameter 2-50 nm , and macropores diameter > 50 nm is generally more effective in adsorbing a wide range of pollutants. Micropores are particularly important for adsorbing small molecules, while mesopores and macropores facilitate the transport of pollutants to the micropores.By carefully selecting the precursor materials, activation process, and post-treatment methods, we can manipulate the pore size and surface area of activated carbon to optimize its efficiency in adsorbing pollutants from water. This will result in better water purification and a more sustainable solution for clean water supply.