The feasibility of adopting zeolite in phosphorus removal from aqueous solutions

Abstract

Excess phosphorus in waterways can cause serious eutrophication, a phenomenon which could eventually result in water quality crisis. Thus, there is a need to seek appropriate ways to remove phosphorus from wastewater. This investigation evaluates the potential of two types of sorbents, granular zeolite (A) and globular zeolite (B), for phosphorus removal. The comparative adsorption of phosphorus from aqueous solutions by A and B is tested using batch experiments. For A and B, the assessed optimum pH is 1.8 and 2.0, sorbent dosage 2.5 and 30 g (per 100 ml aqueous solution, and the contact time intervals 20 and 40 min, respectively. The initial phosphorus concentration for both sorbents was 20 mg/L. The analysis of the results demonstrates that sorbent A has better adsorption characteristics than B. To describe the equilibrium adsorption isotherms, Langmuir and Freundlich models are applied to the data. The Langmuir isotherm adequately describes adsorption for both of these sorbents, with an R² goodness of fit of 0.9792 for A and 0.9835 for B, respectively.

Keywords:

• Phosphorus removal
• Zeolite
• Equilibrium isotherm

Acknowledgments

The authors acknowledge the support by a grant from China Postdoctoral Science Foundation (Grant No. 2012M521367), National Natural Science Foundation of China (Grant No. 50974082), and Shandong University of Science and Technology (Grant No. 2010AZZ014). We also thank Stephanie Ashbolt (CSIRO) for her language support.