Evaluation of zeolite-iron dust composite for removal of Cd from aqueous solution

Today, zeolites are considered as an ideal absorbent for the removal of heavy metals from aquatic environments. zeolites can be used in a composite system with other materials in order to intensify the adsorption capacity. these adsorbent are classified as a low cost adsorbent which is economically reasonable to use. besides, solid waste can be used as a low cost adsorbent which has the ability to remove heavy metals from aqueous solution. In this research, the efficiency Composite of zeolite-iron fly ash was investigated and then optimum conditions and isotherm models (two and three parameters ( And kinetics (first-order, second-order, and intra particle diffusion) were investigated. The best absorption conditions for this adsorbent was for the amount of 0.4 grams of iron fly ash,0.6 grams of zeolite, occurred at the time of 40 minutes and in (Ph = 5.5). The best kinetic model with was a pseudo-second-order model. Also, the best isotherm model was the Langmuir model with 0.957 = 2R. According to this model, the maximum amount of adsorbed cadmium per gram of adsorbent was reported 82.6 mg / g. The adsorption energy according to the Doubenin-Radushkevich was E = 10kj, indicating chemical absorption.