Technological basis of the process of zirconium and hafnium separation

The paper presents the results of industrial testing of the process and equipment for the extraction separation of zirconium and hafnium in a single technological cycle with the production of high-purity nitrate compounds and pure nitric acid solutions as raw materials for the production of sodium nitrate. It is shown that the efficiency of the extraction process is determined primarily by the purity of the nitric acid solution by the content of a critical impurity – silicic acid, which causes an undesirable emulsification process and disrupts the stability of the process. Optimal conditions have been determined under which the formation of non-extractable forms of zirconium and hafnium is excluded. The replacement of pulsating columns with centrifugal extractors reduced operating costs by reducing the volume of a one-time load of a flammable extractant and its losses as a result of hydrolysis. This increased the degree of separation of zirconium and hafnium. Centrifugal extractors provided high process kinetics, reduced production areas, and increased labor productivity and product quality.