Solubility of Platinum in Molten Fluxes as a Measure of Basicity

测定了铂在BaO-Al_2O_3、BaO-SiO_2、CaO-Al_2O_3、NaO_(0.5)-SiO_2、CaO-Al_2O_3-SiO_2、BaO-MoO_X和BaO-CuO_X熔体中的溶解度，以寻求一种新的含过渡金属离子的高碱性熔剂碱度的测量方法。研究了铂的溶解度、其他精炼指标(如碳酸盐、硫化物和磷酸盐的容量)和碱性氧化物活性之间的关系。铂的溶解度与碳酸盐、硫化物和磷酸盐的容量以及碱性氧化物的容量呈对数形式的线性关系。通过考察铂的溶解度与氧分压的关系以及铂的溶解度与碳酸盐、硫化物和磷酸盐容量等其他精炼指标的关系，提出了铂在熔剂中的离子形态为PtO_2^和lt；2-。铂的溶解度可以很好地指示含有过渡金属离子的高碱性熔剂的碱性。焊剂的碱度可以用一种简单的方法来估计，那就是将焊剂熔化在铂坩埚中。

The solubility of platinum in the molten BaO-Al_2O_3, BaO-SiO_2, CaO-Al_2O_3, NaO_<0.5>-SiO_2, CaO-Al_2O_3-SiO_2, BaO-MuO_X, and BaO-CuO_X melts has been measured in order to seek a new measure of the basicity of highly basic fluxes containing transition metal ions.The solubility of platinum increases with increasing the content of basic oxide. The correlations among the solubility of platinum, other refining indexes (such as carbonate, sulfide, and phosphate capacities), and basic oxide activity have been investigated. The solubility of platinum has a linear relationship with carbonate, sulfide, and phosphate capacities, and the basic oxide capacity in logarithmic form.The ionic form of platinum in molten fluxes is suggested as PtO_2^<2-> by examining the dependence of the solubility of platinum on the oxygen partial pressure and on the relationship between the solubility of platinum and other refining indexes, such as carbonate, sulfide, and phosphate capacities.The solubility of platinum may be a good indicator of the basicity of highly basic fluxes containing transition metal ions. The basicity of fluxes may be estimated by an easy method that a flux is fused in a platinum crucible.