Removal of Dissolved Organic Compounds and Contaminants from Wastewater of a Petroleum Refinery by Ion Exchange

Abstract

The efficient removal of dissolved organic compounds (DOC) from wastewater has become a major environmental concern because of its high toxicity even at low concentrations. Therefore, a technique was needed to reduce these pollutants. Ion exchange technology (IE) was used with Amberlite^TM IR120 Na, Amberlite^TM IR96RF, and Amberlite^TM IR402, firstly by using anion and mixed bed system, where the following variables are investigated for the process of adsorption: The height of the bed in column (8,10 and 14 cm), different concentrations of (DOC) content at constant flow rate. The use of an ion exchanger unit (continuous system) with three columns (cation, anion, and mixed bed) was studied. The effect of the following variables, such as a change in temperatures (23,30 and 40 C^o) and the change in flow rate (2,4,6 L/min) was studied. The results showed that the adsorption capacity decreased with increasing the flow rate. The linear equation models of (Langmuir, Freundlich, Timken, and Dubinin-Radushkevich) were used. The results were analyzed using three known models for equilibrium and temperature constant. Graphically, the Langmuir model was the most consistent with the adsorption results because it has the highest adsorption capacity and the highest correlation value of R² = 0.97. The ion exchange column dynamics were studied using models such as (Thomas model). The results showed that the experimental results were well correlated with the model equations. While the tests showed that the removal rate of pollutants was up to 90% for organic compounds.