摘要
提出了以二乙基二硫代甲酸钠螯合铬（Ⅵ）作为载体共沉淀富集水体中铁、锰、锌和镉的方法。沉淀经离心分离,甲基异丁酮溶解后,以微量进样300 μL火焰原子吸收光谱法测定铁、锰、锌,以石墨炉原子吸收光谱法测定镉。用水样10.0 mL,在pH 4.6的邻苯二甲酸氢钾缓冲介质中加入20 g·L-1重铬酸钾溶液150 μL,20 g·L-1 DDTC溶液1.0 mL可达到完全共沉淀分离,所得沉淀经离心分离后用甲基异丁酮2.0 mL溶解,并用于AAS分析。在优化的条件下,铁、锰、锌和镉的检出限（3σ）分别为9.0,6.8,1.8,0.03 μg·L-1,相对标准偏差（n=6）在1.8%-3.8%之间。方法用于实际水样的测定,用标准加入法测得回收率在93.7%-105.0%之间。
. Trace amounts of Fe （ Ⅲ ）, Zn （ Ⅱ ）, Mn （ Ⅱ ） and Cd （ Ⅱ ） in environmental water sample was enriched by coprecipitation by DDTC-Cr precipitate. The sample solution （10. 0 mL） was adjusted to pH 4.6 with phosphate buffer solution and 150μL of 20 g . L-1 K2Cr2O2 solution were added to form DDTC-Cr precipitate. One mL of 20 g . L-2 DDTC solution was necessary for complete to precipitation of the 4 elements. The precipitates were separated by centrifugation and dissolved in 2. 0 mL of MIBK, which was used for AAS determinatiorL The volume of the MIBK solution introduced for AAS analysis was 300 μL, and Fe（ Ⅲ ）, Zn（ Ⅱ ）, Mn（Ⅱ ） and CA（ Ⅱ ） were determined by FAAS, while CA（ Ⅱ ） was determined by GFFAAS. Under the optimum conditions, values of detection limit （3s/k） found were （μg . L-1） 9. 0 （for Fe）, 6. 8 （for Mn）, l. 8 （for Zn） and 0. 03 （for CA）. Values of RSD＇s （n=6） found were in the range of 1.8% --3. 8% respectively. Recovery was tested on the base of samples of sea water and river water by standard addition method, giving results in the range of 93. 7%--105.0% .
出处
《理化检验（化学分册）》
CAS
CSCD
北大核心
2010年第1期84-86,共3页
Physical Testing and Chemical Analysis(Part B:Chemical Analysis)
