摘要
在试样溶解过程中，加入氢氟酸与高氯酸，蒸发使硅以SiF4状态除去，并蒸发至高氯酸冒烟使磷氧化为正磷酸离子（PO4^3-）。分取部分试样溶液，用离子交换分离法将PO4^3-与大量铁（Ⅲ）及其他共存的阳离子分离。收集淋洗液于容量瓶中，加入已知过量的铅标准溶液使生成磷酸铅沉淀。用火焰原子吸收光谱法测定溶液中过量的铅离子，从而间接求得试样中磷的含量。吸光度与磷的质量浓度在2．0mg·L^-1以内呈线性关系。方法的检出限为5．9μg·L^-1，应用此方法测定了3件标准样品的磷含量，测得结果与证书值相符，分析结果的相对标准偏差（n=11）在1．7％～4．0％之间。
In dissolution of sample, silicon was expelled as SiG lay evaporation with HF and HClO4, wnue phosphorus was oxidized to PO4^3- simultaneously in fuming with HClO4. An aliquot of the sample solution was taken and the orthophosphate in the solution was separated from the matrix Fe（ Ⅲ ） and other co-existing cations by cation exchange. Eluates from the ion-exchange column were collected in a volumetric flask and the PO4^3- in the solution was precipitated as lead phosphate by reacting with an excess amount of lead standard solution. Content of phosphorus was found indirectly by FAAS determination of excess amount of Pb^2＋ ion in the filtrate. Linear relationship between values of absorbance and concentration of phosphorus was found in the range within 2. 0 mg · L^-1, with a detection limit of 5. 9μg · L^-1. The proposed method was applied to the determination of 3 standard samples, giving results in consistency with the certified values, and values of RSD＇s （n= 11） in the range of 1. 7%-4. 0%.
出处
《理化检验（化学分册）》
CAS
CSCD
北大核心
2008年第10期972-974,共3页
Physical Testing and Chemical Analysis(Part B:Chemical Analysis)
