论文部分内容阅读
A highly selective ligand exchange type adsorbent was developed for the removal of trace arsenic(V) (As(V)) and phosphate from water. This adsorbent was prepared by loading zirconium(IV) on monophosphonic acid resin. This adsorbent was able to remove toxi canions efficiently at wide pH ranges. However, low pH was preferable for maximum breakthrough capacity in an adsorption operation.The effect of a large amount of competing anions such as chloride, bicarbonate, and sulfate on the adsorption systems of As(V) andphosphate anions was investigated. The experimental findings revealed that the As(V) and phosphate uptakes were not affiected by thesecompeting anions despite the enhancement of the breakthrough points and total adsorption. Phosphate anion was slightly preferablethan As(V) in their competitive adsorption by the adsorbent. The adsorbed As(V) and phosphate on the Zr(IV)-loaded resin werequantitatively eluted with 0.1 mol/L sodium hydroxide solution, and the adsorbent was regenerated by 0.5 mol/L sulfuric acid. Duringseveral cycles of adsorption-elution-regeneration operations, no Zr(IV) was detected in the column efluents. Therefore, the Zr(IV)-loaded monophosphonic acid resin is an effective ligand exchange adsorbent for removing trace concentrations of As(V) and phosphatefrom water.
This adsorbent was prepared by loading zirconium (IV) on monophonic acid resin. This adsorbent was able to remove However, low pH was preferred for maximum breakthrough capacity in an adsorption operation. The effect of a large amount of competing anions such as chloride, bicarbonate, and sulfate on the adsorption systems of As (V) and phosphate anions was investigated. The experimental findings revealed that the As (V) and phosphate uptakes were not affiected by thesecompeting anions despite the enhancement of the breakthrough points and total adsorption. Phosphate anion was slightly preferablethan As (V) in their competitive adsorption by the adsorbent . The adsorbed As (V) and phosphate on the Zr (IV) -loaded resin were quantitatively eluted with 0.1 mol / L sodium hydroxide solution, and the adsorbent was regenerat ed by 0.5 mol / L sulfuric acid. During the cycles of adsorption-elution-regeneration operations, no Zr (IV) was detected in the column efluents. Thus, the Zr (IV) -loaded monophosphonic acid resin is an effective ligand exchange adsorbent for removing trace concentrations of As (V) and phosphatefrom water.