Activated carbon (AC) was prepared from date palm leaves by phosphoric acid activation. The factors affecting the carbon percentage yield such as phosphoric acid concentration, synthesis temperature, and heating time were studied. The prepared AC was studied by chemical analysis of the functional groups on its surface. The prepared AC was decorated with silver nanoparticles (Ag NPs) by in-situ reduction of adsorbed silver ion. Silver ions were introduced on carbon surface by adsorption and ion exchange. Characterization of the prepared AC was performed using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), infra-red spectroscopy (IR), and thermogravimetric analysis (TGA). Results showed that silver ions are impregnated and reduced to Ago NPs with sizes between 30 and 50 nm on the surface of AC. The disinfection properties of Ag-loaded AC were tested for Escherichia Coli and Staphylococci bacteria. The removal of some inorganic disinfection by products (DBPs) including iodate, chlorate, chlorite, and bromate were tested. The results showed that the prepared AC-Ag is effective for antibacterial disinfection and inorganic anions removal applications.