Effect of Structural Modification of Polyurethane Foam by Activated Carbon on the Adsorption of Oil Contaminants from Water

This study investigates both the capacity of pure polyurethane foam in adsorbing oil contaminants and the effect of its structural modification by activated carbon (composite) on the performance of the foam in terms of adsorption capacity and efficiency. To this end, pure polyurethane foam and its activated carbon composites were synthesized and crude oil removal tests were conducted with initial crude oil concentrations of 20 to 280 g/L. Experimental results showed that the optimum weight percentage of activated carbon introduced into the foam structure was 5% wt, which enhanced adsorption capacity by up to 21%. The presence of activated carbon in the foam structure increased the hydrophobicity of the composites while, at the optimal concentration of activated carbon, its adsorption efficiency increased by up to 73% for an initial oil concentration of 20 g/L. Equilibrium studies showed that the Langmuir and Redlich-Peterson isotherms were the fitting ones for oil removal adsorption description. Chemical recovery of the sorbents used was performed using oil solvents (toluene and petroleum ether), which confirmed enhancement in both adsorption efficiency and capacity of the pure sorbent foam and the composite adsorbent.