Viscosity of melts of the system KCl-KBF4-K2TiF6

The viscosity of melts of the system KCl-KBF4-K2TiF6 has been measured by means of the computerized torsional pendulum method. The viscosity of KCl is higher that of KBF4 at the same temperature, most probably due to the substantial overheating of KBF4. In the ternary system the viscosity increases with increasing with increasing content of K2TiF6. Additivity of algorithms of viscosity was adopted as the ideal behaviour of the mixture. Negative deviations from such additive behaviour were found in the binary system KCl-KBF4 probably due to the breaks of the weak B-Cl-B bridges caused by the excess of Cl- ions. Positive deviations from the ideal behaviour were found in the binaries KCl-K2TiF6 and KBF4-K2TiF6 due to the formation of larger anions TiF6Cl3- and TiF73- caused by the reactions K2TiF6(l) + KCl(l) = K3TiF6Cl(l) and KBF4(l) + K2TiF6(l) = K3TiF7(l) + BF3(g). Statistically significant ternary interaction confirmed that the above chemical reactions take place also in the ternary system. (authors)