微波消解ICP-AES法测定土壤中的金属元素研究

采用硝酸-盐酸-氢氟酸-双氧水作溶剂,通过微波消解技术、电感耦合等离子发射光谱法测定土壤中的锑、砷、铍、镉、铬、铜、铅、镍、硒、银、铊、锌,优化了微波消解仪和等离子发射光谱仪的工作参数,研究了共存离子的干扰和消除方法。优化后的微波消解酸体系及用量比例为HNO3∶HCl∶HF∶H2O2=5∶2∶3∶1,方法线性良好,各元素的检出限在0.000 2 mg/L~0.010 1 mg/L之间,土壤样品测定的标准偏差在0.001~0.051之间,加标回收率在85.5%~108.5%之间。该方法检出限低、精密度高、准确度好,测定结果令人满意。

Determination of Metals in Soil by Inductively Coupled Plasma Atomic Emission Spectrometry with Microwave Digestion

The method was established for determining antimony, arsenic, beryllium, cadmium, chromium, copper, lead, nickel, zinc, silver, thallium and selenium in the soil using HNO3 -HCl- HF- H2O2 as solvent by ICP- AES with microwave digestion technique. The parameters for microwave digestion and ICP instrumental operation were optimized by experiments. The interference from coexistent ions on determination and the interference eliminating methods were studied. The improved microwave digestion acid reagents were HNO3 ： HC1 ： HF ： H2O2 =5 ： 2 ： 3 ： 1. The experimental conditions were optimized to produce the following results： good linearity, the detection limits of all elements from 0. 000 2 mg/L to 0. 010 1 mg/L, the standard deviations of the soil samples from 0. 001 to 0. 051, the recoveries from 85.5 % to 108.5%. The established method was proved to be consistent with the low detection limit, high precision and good accuracy.