Adsorption of Phenol Compounds by Nanoporous Silica Aerogel

Abstract

Phenolic compounds are important environmental pollutants that removing and separating them from the water and industrial wastewater, especially in the oil industry, are essential before entering the environment. At present research, the efficiency of the adsorbent silica aerogel for removing 4-Chlorophenol(4-CP) and 4-Bromophenol(4-BP) as phenolic compounds from aqueous solution was studied. Then, the effects of various factors such as contact time, pH and initial concentration were analyzed. It was observed that the amount of adsorption increases at low pH and this amount increases by incrementing the concentration of the emissions. Additionally, increasing the amount of adsorbent causes a decrease in halophenols. Results show that 4-BP much better than 4-CP adsorbed onto silica aerogel. Langmuir and Freundlich adsorption isotherms have been applied to model the equilibrium adsorption data. The study on the adsorption isotherms of these contaminants show that adsorption of these emissions follows the Freundlich isotherm. In addition, adsorption kinetics using pseudo-first-order equation, pseudo-second order, elovich and intra-particle diffusion model were analyzed. The results showed that the uptake of these compounds follows the intra-particle diffusion model and pseudo-second order equation