Investigation of Phenol Removal from Aqueous Solutions Using Copper-Impregnated Pumice

Recently, treatment of industrial wastewaters has attracted much attention of many governments and also environmental experts. Basically, these wastewaters are polluted due to the different contaminants such as dyes, halogenated hydrocarbons, phenolic compounds etc. Among these pollutants, phenols are widely used in petroleum, petrochemical, coal production and pharmaceutical industries. There are several methods for removing phenol from water including adsorption, wet peroxide oxidation, wet air oxidation, ozonation etc. Each of these methods has advantages and disadvantages. Therefore, in this study the adsorption of phenol on Copper modified pumice as an adsorbent was investigated. In this experimental study, the pumice granules were collected from Qorveh region in Kordestan with mesh 20. The pumice granules were modified by CuSO4. Synthetic solution of phenol was prepared and different parameters including pH (3, 7, 12) initial concentration of phenol (25, 50, 75, 100, 150, 200, 300,400 mg/L), contact time (20, 40, 60, 80,100,120 min) and the adsorbent dose of modified pumice (0.25, 0.5, 0.75, 1) were examined in a batch reactor, respectively. The chemical composition and solid structure of pumice was analyzed using X-ray diffraction (XRD), XRF, and scanning electronic microscopy (SEM). Also, Langmuir and Freundlich models were studied in the sorption of phenol onto the pumice. To determine the optimum pH of adsorption process, pHPZC of pumice was measured. The results showed that phenol removal efficiency had been increased by increasing contact time, initial concentration of phenol and the amount of modified pumice. On the other hand, removal efficiency decreased with increasing pH. The sorption process showed a good agreement with the Freundlich model. Also, pHPZC of modified pumice was 7.7. The results show that modified pumice can be used effectively in removing phenol. Due to the low price of the pumice and its simple modification, it can be used for removing hazardous materials from water and wastewater.