微晶蒽分离富集测定痕量铜(Ⅱ)

Trace Copper Determination in Environmental Samples via Separation and Preconcentration on Microcrystalline Anthracene

建立了一种利用微晶蒽吸附分离富集环境水样中痕量Cu(Ⅱ)的新方法。研究表明,pH=3.0时,Cu(Ⅱ)与1-(2-吡啶偶氮)-2-萘酚形成红棕色螯合物被微晶蒽定量吸附,而Pb(Ⅱ)、Mn(Ⅱ)、Co(Ⅱ)、Ni(Ⅱ)、Cd(Ⅱ)、Zn(Ⅱ)、Fe(Ⅲ)和Al(Ⅲ)等完全留在溶液中,从而实现Cu(Ⅱ)与它们的分离。该方法可直接用于1 L水样中痕量Cu(Ⅱ)的分离与富集,富集倍数达200倍,回收率91.0%～104.0%,最低检出限为0.026μg/L;应用于不同水样中Cu(Ⅱ)的测定,结果令人满意。

A new method using microcrystalline anthracene as an adsorbent to separate and preconcentrate trace copper in environmental water samples has been developed.Effects of different parameters,such as the acidity,types of salt,amounts of 1-（2-pyridylazo）-2-naphthol（PAN） and anthracene,preconcentration time,etc.on the enrichment yield of Cu（Ⅱ） have been investigated.The results indicate that at pH=3.00,a red chelate complex generated by the reaction between Cu（Ⅱ） and PAN can be quantitatively adsorbed on the surface of microcrystalline anthracene,whereas Pb（Ⅱ）,Mn（Ⅱ）,Co（Ⅱ）,Ni（Ⅱ）,Cd（Ⅱ）,Zn（Ⅱ）,Fe（Ⅲ）,Al（Ⅲ） etc.completely remain in the solution.Therefore,the aim of separation and preconcentration of trace copper could be achieved.The possible reaction mechanism of the enrichment of copper is discussed in detail in this paper.The recovery is in the range of 91.0%~104.0% with the enrichment factor of 200.The limit of detection after preconcentration is 0.026 μg/L.The proposed method could be directly applied to the determination of trace copper in different environmental water samples of large volume（1 L） with satisfactory results.