【摘要】 报道了将四羟基蒽醌吸附在稻壳基活性炭上 ,用直接混合法制备成化学修饰电极及其在测定Cr 中的应用。研究表明 ,Cr 的电还原产物Cr 可被该电极吸附 ,产生较灵敏的后行吸附。通过实验考察 ,确定了流动注射安培法测定Cr 的最佳操作条件。支持电解质为 0 .0 6mol/L的H2 SO4,在 - 0 .6V电位下作计时电流法测定 ,该电极对Cr 在 5 .0× 10 -6～ 1.0× 10 -3 mol/L范围内有良好的线性响应 ;检出限为 4 .3×10 -7mol/L ;Mg2 + 、Mn2 + 、Al3 + 和Fe3 + 等 10余种共存离子基本不干扰。每次进样后用底液洗脱 5 0s ,可不必更新电极表面。更多还原

【Abstract】 A Flow injection amperometric method for the determination of Cr in water samples, based on the redox reaction of Cr on the modified electrode was proposed and the rection mechanism of the product adsorption on the surface of the electrode was discussed. The modified electrode was prepared by mixed the carbon paste with the activated carbon adsorbed tetrahydroxyanthraquinone(THAQ). It exhibited a linear response to Cr in the concentration range from 5.0×10 -6 to 1.0×10 -3 mol/L with a very good selectivity over a wide variety of metal ions at -0.6 V in 0.06 mol/L H 2SO 4 aqueous solution. It does not need to refershment the surface of electrode, if the interval between the two samping was longer than 50 s.更多还原