Thermogravimetric method for simultaneous determination of potassium and ammonium involving thermal decomposition of tetraphenylborates

A new method for simultaneous determination of ammonium and potassium involving precipitation and thermal decomposition of K[B(C6H5)(4)] and NH4[B(C6H5)(4)] has been presented. Decomposition of tetraphenylborates has been carried out using a derivatograph and a thermoanalyser coupled with a mass spectrometer. Gaseous products of decomposition have been identified. Determination procedure of potassium and ammonium has been developed on the basis of the results of thermal decomposition. The proposed method is very simple. It is based on the determination of the mass loss of tetraphenylborate precipitate. The results of the analysis have been calculated from the calibration plot constructed for the two-component system. The method has been applied to the analysis of urine.