Purification of brines of sodium chloride from trace contaminants in the production of chlorine and caustic soda in processes of precipitation and coprecipitation

The requirements to composition and quality of brines in diaphragm, mercuric and membrane methods of electrolysis are considered. The role of trace contaminants on different levels of electrolysis process, output and quality of end products, methods of trace contaminants removal from brines are considered as well. The influence of concentrations of Na₂CO₃ and NaOH, iron chloride (III), duration, ph, temperature, polyacrylamide additive on conditions of extraction of Ca²⁺ and Mg²⁺in the form of Mg(OH)₂ in static regime is studied. The method of deep purification of NaCl brines from admixtures in dynamic conditions is elaborated.