摘要
选用硝酸-氢氟酸-高氯酸、硝酸-盐酸-氢氟酸-高氯酸2种消解体系,建立了石墨炉原子吸收标准加入校正法测定土壤中镉的方法,能够实现对土壤镉的准确测定。以硝酸钯为基体改进剂,优化灰化温度为550℃,原子化温度为1600℃。分别取土壤标准样品GBW07452、GBW07388经微波消解或全自动消解后,定量加入到标准溶液系列中作基体匹配,绘制校准曲线为y=0.0179x+0.0007、y=0.0191x-0.0004,线性良好,检出限分别为0.007 mg/kg、0.008 mg/kg,均低于GB/T 17141-1997的标准检出限。对3种不同浓度的国家一级土壤标准物质进行了测定,镉测定结果均在标准值范围内,相对标准偏差在5%以内,说明该方法准确度高、精密度好、检出限低,适用于批量样品的分析测定。
Nitric acid-hydrofluoric acid-perchloric acid solution and nitric acid-hydrochloric acid-hydrofluoric acid-perchloric acid solution were adopted to establish a determination method of cadmium in soil by standard addition correction method of graphite furnace atomic absorption spectrometry.It could realize the accurate determination of soil cadmium.In this experiment,palladium nitrate was used as matrix modifier.The optimized GFAAS ashing temperature was 550℃and the atomization temperature was 1600℃.The soil standard samples GBW07452 and GBW07388 were digested by microwave digestion instrument or automatic digestion instrument,and then quantitatively added in standard solution for matrix matching.The calibration curve equations of cadmium were y=0.0179x+0.0007 and y=0.0191x-0.0004,respectively,and the linear relation were good.The detection limits were 0.007mg/kg and 0.008mg/kg,respectively,which were lower than the standard detection limits of GB/T 17141-1997.The method had high precision and accuracy because the determination results of three standard soil samples with different cadmium concentrations were consistent with the standard values and the relative standard(RSD)was within 5%.So it was suitable for the determination of cadmium in batches of soil samples.
作者
王夏
李媛
孙瑞玲
Wang Xia;Li Yuan;Sun Ruiling(Gansu Environmental Monitoring Center Station,Lanzhou,Gansu 730020,China)
出处
《绿色科技》
2022年第2期126-129,133,共5页
Journal of Green Science and Technology
关键词
土壤
镉
石墨炉原子吸收光谱法
标准加入校正法
soil
cadmium
graphite furnace atomic absorption spectrometry
standard addition correction method
