以DDTP为化学改进剂,低温电热蒸发ICP-OES测定环境样品中的钴和镍

Determination Co and Ni in environmental samples by low temperature electrothermal vaporization inductively coupled plasma optical emission spectrometry using diethyldithiophosphate(DDTP) as a chemical modifier

提出了以二乙基二硫代磷酸(DDTP)为化学改进剂,低温电热蒸发ICP-OES法检测环境样品中的钴和镍,对影响金属螯合物形成及其蒸发条件进行了考察与优化。试验结果表明,在pH>4.5,DDTP质量浓度为8.0 g/L的条件下,试剂DDTP可与钴(Ⅱ),镍(Ⅱ)形成稳定的螯合物。并以螯合物的气态形式从石墨炉中,定量蒸发和传输至等离子体中,用于ETV-ICP-OES检测。钴(Ⅱ)和镍(Ⅱ)的检出限分别为19.6和17.3μg/L,与常规的ETV-ICP-OES法相比待测元素的蒸发温度降低了1200℃左右。方法已用于土壤和水系沉积物标准样品中钴和镍的检测。

A new method for the determination of Co and Ni in environmental samples by low temperature electrothermal vaporization inductively coupled plasma optical emission spectrometry using diethyldithiophos-phate （DDTP） as the chemical modifier is developed. The conditions that influence the formation and the vaporization of complexes are stud- ied. When pH is above 4.5 and concentration of DDTP is 0.8% （ m/v）, steady complexes are formed and can be vaporized under 1800℃ from graphite furnace into ICP. The detection limits of Co and Ni are 19.6 and 17.3 μg/mL. Vaporization temperature in this method is 1200 ℃ lower than normal ETV-ICP-OES. This method is used to determinate Co and Ni in soil and sediment samples, and satisfactory results can be obtained.