Adsorption of Arsenic (III) onto Two Iron-Coated Zeolites

The applicability of two iron-coated zeolites prepared by alkalescent deposition and heating evaporation for the treatment of As(III) via adsorption processes was investigated. Scanning electron microscopy (SEM), X-ray diffraction spectroscopy (XRD) and BET were used to observe the surface properties of the coated layer. The influences of different sorption parameters such as contact time, dosing quantity , initial arsenic concentration and solution pH were also studied thoroughly in order to optimize the reaction conditions.In this paper, various dosage of two iron-coated zeolites were reacted at 30(±1) °C for up to 80 min with 100 mL of 0.3mg/L As(III) solution. Arsenic concentration decreased exponentially with time and dosing quantity, and pseudoequilibrium was attained in 30 min when the dosing quantity was 1 gram, two iron-coated zeolites estimated adsorption capacities were 26.92 and 30 μg/g for As(III), respectively. For solution pH, the iron-coated zeolites prepared by heating evaporation were near 10 and the iron-coated zeolites prepared by alkalescent deposition were near 5. The values of the parameter sets of the isotherms also indicated that removing As(III) was a single molecular layer adsorption.