China Nonferrous Metallurgy

The content of sodium are important indexes to evaluate the quality of potassium fluotitanate, potassium fluoroborate and potassium fluorozirconate. At present, there are no relevant standard methods for the analysis of sodium in potassium fluotitanate and potassium fluorozirconate. The determination method of sodium in potassium fluoroborate can no longer meet determination of sodium in potassium fluotitanate and potassium fluorozirconate. In order to solve this problem, this study carried out experiments of pretreatment of samples with various acids, and investigated the effects of titanium matrix and zirconium matrix on sodium determination. The results show that potassium fuotitanate, potassium fluoborate and potassium fluorozirconate samples can be completely dissolved by the method of “sulfuric acid dissolution+sulfuric acid smoking” to drive away fluorine. Under the selected conditions, titanium and zirconium matrix have no effect on the determination of sodium; Deionizing agents cesium chloride and strontium chloride are not needed in the determination process. The recovery rate of this method is between 84.0% and 113.9%, which is consistent with the determination results of inductively coupled plasma emission spectrometry. The relative standard deviation of this method is between 5.39% and 9.56%, which can meet the needs of rapid and accurate determination of sodium content in potassium fluotitanate, potassium fluoborate and potassium fluoacetate, and the determination range is 0.0050%~0.5000%. The study is an important supplement to the existing standards for the determination of sodium in fluoride salt.