| Antimony is one poisonous element and widely used in alloys andsemiconductors et al. As a result, it is inevitably that drinking water systems will bepolluted by antimony. Therefore, it is necessary to develop new methods andtechnologies for removing antimony from drinking water. In this paper, theperformance of the removal of antimony（III） from aqueous solution by copper-zincalloy filter media was investigated in detail. The optimal experimental conditionsincluding filter material particle size, pH, filter media dose, contact time, andtemperature were obtained by the batch experiments. The various column parameters,such as flow rate, height of filter media, initial concentration were evaluated. And theinfluence of some co-existing ions on the removal of antimony（III） was also studied.Moreover, the adsorption kinetics, thermodynamic behavior and mechanism werealso discussed. The research results will provide theoretical basis and experimentaldate for the practical application of the filter for the removal of the antimony（III）from drinking water. The main experimental results and conclusions were describedas follows:1. Spectrophotometric determination of micro amount of antimony（III） usingsalicyl fluorone-mixing surfactants，the optimal conditions was obtained as follows:2.0mL H2SO4（1+6）,3.0mL20mg·mL-1Tween-80,2.0mL1.0×10-3mol·L(-10salicylfluorine, mixing evenly, the color development reaction completeded after20min,and the wavelength of maximum absorption at510nm. The apparent molaradsorption coefficient is2.06×105L·mol-1·cm-1. The equation of calibration curve isA=0.02395Cμg/25mL+0.04204, the correlation coefficient is r=0.9995.2. The batch experiment result indicated that the maximum removal of antimonywas reached after120min at room temperature and pH6.5, and the correspondingpercent removal is more than99%, while the filter material dosage was kept at5g.The column experiment result revealed that the maximum removal of antimony wasobtained at room temperature, pH6.5, and the corresponding percentage of removal ismore than99%when the flow rate and the height of the filter material bed were kept 75%at2mL/min and3.5cm, respectively. Moreover, the results showed that thepresence of co-existing ions, such as HCO3-and CO32-have positive effects on theremoval of antimony（III）. Other common cations and anions in drinking water havenegligible effects.3. Lagergren second order kinetic model can match the experiment better，itinclude all steps of adsorption such as external film diffusion, adsorption, and internalparticle diffusion. Adsorption rate increase with the increase of temperature, the timeof the system to reach equilibrium is reduced. The Langmuir isotherm model canmatch the experiment better than the Freundlich isotherm model. The equilibriumconstants RLfor the reaction process of removal antimony（III） lies between0and1,which indicated that the sorption could be easily ongoing. Adsorption capacity willincrease when the temperature rise, which indicated that the reaction is anendothermic process. Antimony（III） may be based on the form of a monolayeradsorbed on the surface of the filter, and it is mainly chemical adsorption.Thermodynamic parameter was ΔH0>0，ΔG00，ΔS0>0，which indicated that thereaction is endothermic process. The mechanism of the removal of antimony（III） isaccording to the oxidation-reduction reaction. Antimony（III） is transformed intoantimony atoms combined on the copper-zinc alloy filter media.4. The copper and zinc alloy filter media was used for removing antimony（III）from the synthesized water samples. When a column with a diameter of2.5cm wasused to remove antimony（III） at a flow rate of10L/min and a filter height of10cm,the efficiency of removal of antimony（III） is94%. The experiment show thatcopper-zinc alloy filter can be used for antimony（III） from drinking water andpolluted water, the results are satisfactory. |
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