Redox Equilibrium Between Ti~(3+) and Ti~(4+) in CaO-SiO_2-TiO_2-MgO Molten Slag

摘要

An experimental study has been made of redox equilibrium between Ti~(3+) and Ti~(4+) in CaO-SiO_2-TiO_2-MgO molten slag by means of chemical equilibrium among H_2O/H_2-Cu alloy-slag at 1550°C. The results show that: (1) Ratio %Ti~(4+)/(%Ti~(4+)+%Ti~(3+)) increases linearly with the increment of %CaO/%SiO_2 when %CaO/%SiO_2 is less than 1, and %Ti~(4+)/(%Ti~(4+)+%Ti~(3+)) can be defined as basicity of the slag. (2) Ratio X_(Ti~(3+)) / X_(Ti~(4+)) decreases linearly with the increasing %CaO/%SiO_2 when %CaO/%SiO_2 is less than 1. (3) Dependence of activity coefficient ratio γ_(TiO_2) / γ _(SiO_2) on X_(TiO_2,Tot) is parabolic, which is independent of P_(H_2O) / P_(H_2) and the lowest value exists at X_(TiO_2,Tot) =0.15.