Analysis of the principle of determination of phosphorus content by acid quinoline weight method and uncertainty evaluation
Liu Huiqiang1,2
1. Hebei Chemical Industry Research Institute，Shijiazhang 050031, China; 2. Hebei Chemical Products Quality Supervision and Inspection Station, Shijiazhang 050031, China
Phosphorus is the common indicator of fertilizer testing, phosphomolybdic acid quinoline weight method is defined by several national standards. The principle of determination of phosphorus content by phosphomolybdic acid quinoline weight method was analyzed in detail from the selection of extractant agent, the composition and function of the precipitation, and aging, filtration and drying process. The measurement sources of uncertainty were analyzed, and the uncertainty was also evaluated from the repeatability test, balance weighting, sample constant volume and splitting etc.. It is suggested that phosphomolybdic acid quinoline weight method has the advantages of similarity between the precipitation composition and the theoretical value, stable composition, large molecular weight, small solubility, coarse precipitation particles, easy filtration, washing and drying to constant weight etc., and its uncertainty is less, the degree of reliability is higher.
刘会强1, 2. 磷钼酸喹啉重量法测定磷含量原理剖析及不确定度评价[J]. 煤炭与化工, 2017, 40(6): 71-76.
Liu Huiqiang1,2. Analysis of the principle of determination of phosphorus content by acid quinoline weight method and uncertainty evaluation. CCI, 2017, 40(6): 71-76.
