Preparation of activated carbon from hemps and their adsorption on Cu2+

Key words: 
• activated carbon /
• adsorption isotherm /
• Frenudlich model

Abstract: Powdered active carbon (PAC) was prepared from hemp rope waste as raw materials and potassium hydroxide as activating agent. It was studied through static test to evaluate the effect of various parameters such as pH, adsorbent dose, contact time and initial Cu2+ concentration on the adsorption of Cu2+ by PAC. Results showed that the initial pH and activated carbon dosage had greater influence on the adsorption of Cu2+, the adsorption of Cu2+ by activated carbon was a rapid process, and in 60 min the adsorption rate reached more than 50%, the adsorption amount was approximately proportional to the initial concentration(10～50 mg/L). Langmuir and Freundlich isotherms were used to fit the equilibrium data, and it was found that the adsorption isotherm followed the Frenudlich model. The function groups on activated carbon were analyzed by FT-IR spectroscopy, and it was showed that surface functional groups were the active center.