Phenol Removal from Aqueous Solutions by Adsorption on Activated Carbon of Miswak’s Root Treated with KMnO4

Background and Purpose: Phenol and derivatives are common pollutants of drinking water which are blamed for crucial adverse effects such as poisoning, cancer, and malformation. In this study, an activated carbon of Miswak’s root (MR) was used for the removal of phenol from aqueous solutions as a low-cost and high surface adsorbent. Materials and Methods: Adsorption experiments were then conducted in a batch reactor with activated carbon prepared from MR and treated with KMnO4 to study the effects of contact time (0-180 minutes), pH (3-13), initial phenol concentration (100-1000 mg/L), and adsorbent dosage (0.1-1 g/L) at lab temperature 30 ± 1° C on sorption efficiency. KMnO4 treatment influenced the physicochemical properties of the carbon and improved its adsorption rate. Results: The results showed that the equilibrium time of adsorption was 120 minutes maximum adsorption capacity (94.76% phenol removed) of the MR carbon was 142.15 mg/g at pH 5, the initial concentration of 100 mg/L, 30° C and 180 minutes contact time. The optimum type of MR adsorbent was produced in 800° C. The equilibrium data were analyzed by the Langmuir and Freundlich isotherms and fitted well with the Freundlich model (R2 = 0.9821) better than Langmuir (R2 = 0.7551) model. Conclusion: The results revealed that the carbon of MR modified with KMnO4 had a satisfactory quality in phenol adsorption and can well be used as a novel, inexpensive, effective, and efficient adsorbent for the removal of phenol from the aquatic environment.