摘要
取0.2500 g地质样品,加入约1.5 g过氧化钠,于700℃熔融20 min,冷却后加入微沸水30 mL浸取熔块,再滴加5滴无水乙醇,用水定容至50 mL。分取10.00 mL上清液,滴加3~4滴1 g·L^(-1)酚酞指示剂,用10%(体积分数,下同)盐酸溶液中和至无色后再加入10%盐酸溶液10 mL以及硫脲和抗坏血酸质量浓度均为50 g·L^(-1)的混合液5 mL,用水稀释至50 mL,在灯电流80 mA、原子化器高度8 mm、光电倍增管负高压300 V、载气流量400 mL·min^(-1)、屏蔽气流量1000 mL·min^(-1)、硼氢化钾质量浓度30.00 g·L^(-1)下采用原子荧光光谱仪测定溶液中Sn的含量。结果表明:Sn的质量浓度在150.00μg·L^(-1)以内与荧光强度呈线性关系,相关系数为0.9993,检出限(3s/k)为0.42μg·g^(-1);方法用于地质标准物质分析时,测定值的相对标准偏差(n=12)为3.7%,相对误差的绝对值小于10%,且测定值与认定值的对数差(△lg C)的绝对值小于0.10。方法用于土壤、水系沉积物和岩石样品的分析,测定值与电弧发射光谱法的基本一致。
The 0.2500 g of geological sample was taken,and about 1.5 g of sodium peroxide was added.The mixture was melt at 700℃for 20 min,and cooled down.Then 30 mL of slightly boiling water was added to leach the melt,and 5 drops of anhydrous ethanol were added.The solution was made its volume up to 50 mL by water.The 10.00 mL of supernatant was taken,and 3-4 drops of 1 g·L^(−1) phenolphthalein indicator were added.The 10%(volume fraction,the same below)hydrochloric acid solution was added to neutralize until colorless,and 10 mL of 10%hydrochloric acid solution and 5 mL of the mixed solution containing thiourea and ascorbic acid with the same mass concentration of 50 g·L^(−1) were added.The solution was diluted to 50 mL by water for determination of Sn by atomic fluorescence spectrometer at lamp current of 80 mA,atomizer height of 8 mm,photomultiplier negative high voltage of 300 V,carrier gas flow of 400 mL·min^(−1),shielding gas flow of 1000 mL·min^(−1),and potassium borohydride mass concentration of 30.00 g·L^(−1).It was shown that linear relationship between the mass concentration and fluorescence intensity of Sn was kept within 150.00μg·L^(−1),with correlation coefficient of 0.9993,and detection limit(3s/k)of 0.42μg·g^(−1).The proposed method was used for the analysis of geological reference materials,giving RSD(n=12)of the determined values of 3.7%,absolute values of the relative error less than 10%,and absolute values of logarithmic difference(ΔlgC)between determined values and certified values less than 0.10.The proposed method was used for the analysis of soil,water sediment,and rock samples,and the determined values were basically consistent with those obtained by arc emission spectroscopy.
作者
黄海波
何袖辉
李民敬
周权平
陆迁树
袁静
张华
申汝佳
HUANG Haibo;HE Xiuhui;LI Minjing;ZHOU Quanping;LU Qianshu;YUAN Jing;ZHANG Hua;SHEN Rujia(Nanjing Center,China Geological Survey,Nanjing 210016,China;School of Environmental Studies,China University of Geosciences,Wuhan 430074,China;East China Center for Geoscience Innovation,Nanjing 210016,China;Kunming General Survey of Natural Resources Center,China Geological Survey,Kunming 650111,China)
出处
《理化检验（化学分册）》
CAS
CSCD
北大核心
2024年第10期1040-1046,共7页
Physical Testing and Chemical Analysis(Part B:Chemical Analysis)
基金
中国地质调查局项目(DD20221728)。
关键词
原子荧光光谱法
地质样品
SN
碱熔
atomic fluorescence spectrometry
geological sample
Sn
alkali fusion
