Journal of Colloid and Interface Science, Vol.464, 277-284, 2016
Investigation on the adsorption of phosphorus by Fe-loaded ceramic adsorbent
This aim of this study was to remove phosphorus from aqueous solution using a Fe-loaded ceramic (Fe-LC) adsorbent prepared by mixing dolomite, montmorillonite, FeSO4 center dot 7H(2)O and starch. Simplex-centroid mixture design method was used to determine the optimum mixture proportions by evaluating both phosphorus adsorption efficiency and adsorbent hardness. The study found that the optimum adsorption capacity and the strength can be achieved with the composition of 3.87 g dolomite, 3.00 g starch, 2.13 g montmorillonite and 1.00 g FeSO4 center dot 7H(2)O (10 g in total). The optimized Fe-LC was evaluated in the batch and the fixed bed experiments. The point of zero charge, pH(PZC) was found to be 6.0. The adsorption kinetic and isotherm data well agreed with the pseudo-second-order kinetic and the Langmuir isotherm models, respectively. The breakthrough time increased with increasing in the bed depth, whereas inverse relationship was observed with the initial phosphorus concentration in the fixed bed studies. The co-existing anions (SO42-, NO3- and Cl-) had negligible influence on phosphorus removal. The BDST and Thomas model explained the breakthrough behavior for phosphorus removal with a high degree of correlation. (C) 2015 Elsevier Inc. All rights reserved.