Determination of cadmium and lead in soil by triacid digestion-graphite furnace atomic absorption spectrometry
CHANG Weihong, LI Jianpo
Water Quality Testing Center, Beijing Drainage Water Environment Development Co., LTD., Beijing 100022, China
三酸消解法进行前处理，以5 g/L 磷酸氢二铵溶液为基体改进剂，采用石墨炉原子吸收光谱法测定样品溶液的
y=0.120 97x+0.009 24 和y=0.005 10x+0.002 81，相关系数均为1.000，镉和铅的检出限分别为0.004，0.08 mg/kg（按称
取0.5 g 试样消解定容至50 mL 计算），均低于GB/T 17141-1997 的标准检出限。对4 种不同土壤样品进行测定，镉
Abstract：A method for determination of cadmium and lead contents in soil by triacid digestion-graphite furnace
atomic absorption spectrometry was establish. Soil samples were pretreated by hydrochloric acid-nitric acid-hydrofluoric
acid digestion method. With 5 g/L diammonium hydrogen phosphate solution as matrix modifier. The absorbance of
sample solution was determined by graphite furnace atomic absorption spectrometry. Calibration curves were drawn and the
contents of cadmium and lead were determined from the calibration curves. Under the selected experimental conditions, the
calibration curve equations of cadmium and lead were y=0.120 97x+0.009 24 and y=0.005 10x+0.002 81, respectively, the
correlation coefficients were all 1.000, and the detection limits of cadmium and lead were 0.004,0.08 mg/kg, respectively,
(according to 0.5 g sample was digested and diluted to 50 mL), which were lower than the standard detection limits of GB/T
17141-1997. Cadmium and lead were measured for four different soils, and the relative standard deviation of cadmium
and lead were 1.5%-2.9%, 1.1%-2.3%(n=8), respectively. The recoveries of cadmium and lead were 98.2%-106.0%
and 98.0%-109.2% in the three various soil samples. This method has the advantages of accurate detection results, good
precision, low detection limits, good applicability and it can be suitable for heavy metal detection in soil samples.
Keywords：graphite furnace atomic absorption spectrometry; hydrochloric acid-nitric acid-hydrofluoric acid digestion; soil; cadmium; lead
昌伟宏，李建坡. 三酸消解- 石墨炉原子吸收法测定土壤中的镉和铅[J]. 化学分析计量，2019，28(Z1)：32-36.
CHANG W H，LI J P. Determination of cadmium and lead in soil by triacid digestion-graphite furnace atomic absorption spectrometry[J]. Chemical analysis and meterage，2019，28(Z1)：32-36.