THE POSSIBILITIES OF POTENTIOMETRIC DETERMINATION OF POTASSIUM IN SOME SILICATE RAW-MATERIALS

Potentiometry using the potassium ion-selective electrode can be conve niently employed to determine rapidly the approximate content of K2O i n silicate raw materials. For the determination, the dried and ignited sample of the material is decomposed by reflux boiling in hydrochlori c acid (9 mol dm-3). Aliquote amounts are taken from the suspension ob tained so as to receive a resulting K2O content over the range of 10(- 2) to 1.5 x 10(-5) mol dm-3 at pH of 0.7 to 0.9. Under the given condi tions, the interfering effect of hydrogen ions occurs only at pK+ = 5.