The Thermodynamic analysis of Ti, As-containing systems based on E-pH diagrams and partial pressures

Abstract

The removal of arsenic from the technological circulation of metallurgical enterprises is a technologically necessary process, leading from year to year to the formation of new volumes of arsenic-containing objects. One of the forms of extracting arsenic from the production stage is arsenates of various metals, which are difficult and poorly soluble compounds. This approach also does not solve environmental issues in general. Thus, titanium arsenates under storage and burial conditions are subject to hydrolysis, which leads to gradual pollution and poisoning of the environment with arsenic-containing compounds. The practical value of titanium and its compounds in economic activities forces us to look for ways to rationally use arsenic-containing titanium compounds.

The article is the first to carry out a thermodynamic analysis of the behavior of arsenic and titanium based on potential-pH diagrams and partial pressures. The course and directions of chemical reactions in titanium- and arsenic-containing systems, the conditions for the stability of their constituent phases, the thermodynamic parameters of the behavior of the participating components, their compounds, the range of their stability, and the redox processes of the formation of chemical products have been studied.

The regions of existence of titanium arsenate are determined, and chemical and electrode reactions for the production of titanium arsenate from titanium and arsenic compounds are considered. The results of the work confirm both the effectiveness of using titanium compounds to remove arsenic from solutions in the form of poorly soluble manganese arsenate, and the possibility of regenerating titanium in the form of oxides and bases.

Key words: thermodynamic systems, diagrams, arsenic compounds, titanium compounds, titanium arsenate.