微波消解植物灰分与环境土壤中微量元素的ICP-AES方法研究

Study of Microelements in Plant’s Ash and Environmental Soil by Microwave Digestion ICP-AES

应用MDS-2002A型压力自控密闭微波消解样品制备系统,针对研究样品的特性和共性,进行植物灰分和土壤样品相同微波消解条件的研究实验,并采用电感耦合等离子体原子发射光谱法测定其元素的含量。讨论了混合酸体系、混酸配比、固液比和微波消解时间对于样品制备结果的影响。最终的优选方案为A2B1C2,即微波程序为工步2,混酸配比为6∶2∶1∶1,混合酸体系为HNO3-HCl-HF-HClO4,最高功率消解时间为10min的条件下,消解结果最佳。在微波消解最佳条件下,进行了方法准确度实验和测量结果重现性实验,该方法经土壤(GBW07401)和植物(GBW07603)国家标准物质验证,所得测试结果的相对误差均在0.00%～7.14%之间,相对标准偏差均在0.87%～5.25%之间。结果表明,微波消解法处理植物灰分和土壤样品,具有快速、简便、节省试剂、消解完全等特点,测定结果的准确度和精密度令人满意。

A model MDS-2002A microwave digestion sample preparation system with auto control pressure in obturation was developed for the determination of microelements in clearing-up plant＇s ash and environment soil sample by ICP-AES. The authors discussed sample preparation result influenced by mixed acid system, scale of mixed acid dispensation, proportion between solid and liquid and time of microwave clearing. Excellent project was A2 B1 C2, work procedure 2 in microwave process. When the dispensation scale was 6 ： 2 ： 1 ： 1 and mixed acid system was HNO3-HCl-HF-HClO4, the result was the best in 10 min of microwave clearing at highest power. The reagent was dried at constant temperature electric heating board, with its salinity being dissolved by aqua fortis. The method was validated through the soil （GBW07401） and plant （GBW07603） for national standard matter. The relative error of its result is between 0. 00% and 7. 14%, and the relative standard deviation is between 0. 87% and 5.25%. The method is quick, handy, saving reagent and completely digesting in dealing with plant＇s ash and soil sample, and the accuracy and precision of results are satisfying.