and physiochemically-activated carbon. Properties of the prepared samples were characterized using nitrogen adsorption–desorption isotherm, pH of zero point charge and Boehm titration method. Results showed that carbonization temperature and activation agents had significant effects on characteristics of the samples. Chemical activation was the most efficient method for production of activated carbons with high surface area and porosity. Physiochemical activation improved mesopores volume of the activated carbons prepared in low KOH ratio. The sodium (Na + ) sorption capability of the carbonaceous adsorbents was increased with increasing surface area, porosity and micropores volume. The highest Na + sorption of 134.2 mg g -1 belonged to chemically-activated carbon produced by KOH/biochar ratio of 3 having the highest surface area (2201 m 2 g -1 ) and total pore volume (0.96 cm 3 g -1 ). Desalination capacity of RH carbonaceous samples from drainage water with TDS of 15179 mg L -1 ranged from 88.5 to 383.2 mg g -1 . Also, canola stalk (CS) was used for preparation of steam- activated carbon. The optimum conditions for maximum desalination capacity (292.1 mg g -1 ) were identified to be a carbonization temperature of 485 °C, activation temperature of 825 °C and activation time of 55 min. Prepared CS steam- activated carbon was efficient in removing hardness cations. Key Words: Biochar, Activated carbon, Rice husk, Canola stalk, Sorption, Desalination
