Ammonium Metatungstate Testing Method
Ammonium metatungstate testing method includes detecting method for AMT impurities and purity, conventional analysis techniques of high purity ammonium metatungstate are graphite furnace atomic absorption spectrometry (GFAAS), flame atomic absorption spectrometry (FAAS) and inductively coupled plasma emission spectrometry (ICP-MS), in addition, there also related research reports about the methods of separating analysis and matrix such as ion exchange, liquid-liquid extraction and co-precipitation method, etc..
Remarks: In the above table, E refers to element; R refers to reference; DL refers to Detection Limit.
The figure above is the comparison of HMI/ICP-MS results and the reference values for six high purity ammonium metatungstate samples, wherein the result of major impurities (such as Na, P, K, As, Mo, Sn, and Sb) are very consistent with the reference value. GB_T 26033-2010 ammonium metatungstate provides the standard of Na, P, K , As, Mo and Sn and other impurities.
In addition, some scholars by co-precipitation separation-hydride generation-atomic fluorescence spectrometry, which also named of co-precipitation method -HG-AFS method to detect trace amounts of bismuth; this testing method of ammonium metatungstate has advantages of high sensitivity, good selectivity and small matrix interference to give a precise impurity content of bismuth.