利用火焰原子吸收光谱法研究了四钛酸钾对镉的吸附性能,提出了用四钛酸钾作为富集剂,预富集、分离环境水样中痕量Cd(Ⅱ)的新方法。结果表明;在pH5.0,四钛酸钾晶须用量为0.10g时,吸附率可达到100%。以10mL 0.5mol/L HCI作为解脱剂,沸水浴加热20min,可将吸附在四钛酸钾上的镉定量洗脱。在优化的实验条件下,环境水样中镉用该法预分离/富集后,用火焰原子吸收光谱法(FAAS)检测,相对标准偏差为2.9%~3.5%,加标回收率为96%~102%。
The adsorption behavior of potassium tetratitanate whisker to cadmium was studied and a new method for pre-concentration and separation of Cd was proposed. The results show that when the dosage of potassium tetratitanate whisker was 0.10 g, its adsorption efficiency might be up to 100 %. Cadmium adsorbed on potassium tetratitanate whisker could be eluted quantitatively with 10 mL of 0. 5 mol/L HCl as the desorption reagent in the boiled water bath for 20 min. Under optimum experimental conditions,cadmium in water sample was pre-concentrated and separated by proposed method and was determined by flame atomic absorption spectrometry(FAAS), with the relative standard deviation of 2.9 %--3.5% and the standard addition recovery of 96 %--102 %.