Strategies for recovering phenol from wastewater: thermodynamic evaluation and environmental concerns

In this work, thermodynamic and environmental insights were used to study the recovery of phenol from wastewater. The liquid-liquid equilibrium calculation and prediction and the residue curve maps (RCM) were explored in a way to analyze the performance of a complete liquid-liquid extraction process to remove phenol. The results have shown that the group-contribution method is a powerful tool to predict binary interaction parameters systems and equilibrium data for which no experimental data are available. Environmental restriction was a constraint in terms of solvent choice and presence in the raffinate stream. Final results show that the plant size is directly related to the selected solvent, when the complete process is considered (liquid-liquid extraction, distillation column, and recycle). Finally, it was identified a lack of experimental liquid-liquid and vapor-liquid data in the open literature related to the binary pairs studied here. (c) 2004 Elsevier B.V. All rights reserved.