Technology of phosphorus slag processing for preparation of precipitated silica

The article presents the results of studying the determination of the influence of the nature of a number of mineral reagents (solutions of hydrochloric, nitric, sulfur and phosphoric acids, as well as sodium hydroxide and carbonate) on silicon extraction in solution upon he leaching of phosphorus production slags. The results of studying the process of the breakdown of phosphorus production slag with sodium carbonate solutions depending on various physicochemical parameters are provided. The optimum conditions of main technological operations were found and the main parameters that influence the morphological structure and size of precipitated silica particles were established. The influence of the conditions of washing of carbonate-silicate cake on its chemical, phase, and granulometric composition has been studied. Scaled-up laboratory tests have been carried out and a technology for processing phosphorus production slags to produce mineral fillers was developed on their basis. Conclusions on the applicability of pilot batches of white soot in tire and paint industries and carbonate-silicate fillers in construction industry and agriculture were obtained.