摘要：

An effective and selective adsorbent, activated carbon loaded with zirconium (Zr-C *), has been developed for the preconcentration of phosphate in environmental water samples. The Zr-C* was prepared by mixing a zirconyl nitrate solution with activated carbon. Phosphate is quantitatively adsorbed onto Zr-C* below pH 8 and quantitatively desorbed above pH 13.5. Such quantitative adsorption and desorption were instantaneously accomplished. These characteristics of Zr-C* enable us to separate and preconcentrate rapidly and selectively low levels of phosphate in environ mental water samples by two rapid preconcetration methods. One is a flow method: a sample solution (pH 1.5) is passed through a Zr-C* bed formed on a membrane filter paper with the aid of suction to preconcentrate phosphate; the collected phosphate is then, recovered by eluting with a l M sodium hydroxide solution. This method is effective for high concentrations of phosphate at low levels. The other method is column solid-phase extraction: a small column packed with Zr-C* is used for the in situ preconcentration of phosphate in field work. Both methods were successfully applied to environmental waters samples.

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