METHOD FOR PROCESSING ALUMINA-CONTAINING RAW MATERIAL AND METHOD FOR OPENING ALUMINA-CONTAINING RAW MATERIAL IN PROCESSING THEREOF Russian patent published in 2016 - IPC C01F7/26 

FIELD: chemistry.

SUBSTANCE: processing method is realised in form of circular process, which includes: opening stage, at which prepared is heated solution-reagent, which contains ammonium hydrosulphate, into which sulphuric acid is added, and decomposition of raw material is carried out with solution-reagent, obtaining pulp, which contains solution of alumoammonium alum with solid residues of decomposition, separation of hot pulp into solid and liquid phases with obtaining non-decomposed solid residues and mother liquor of alum; solid residuals are washed with water. Mother liquor of alum and washing waters are separately collected; stage of purification, at which washing waters are purified from iron by precipitation method, then they are combined with mother liquor of alum with obtaining preliminarily purified mother liquor with the following reduction of iron contained in said solution to bivalent condition and cooling of solution with extraction of alumoammonium alum, their separation from mother liquor and dissolution in pure water with obtaining alum solution purified from iron admixtures. From mother liquor extracted is sulphuric acid, which is then applied at opening stage in preparation of solution-reagent; stage of precipitation, at which obtained is aluminium hydroxide, precipitated from alum solution purified from iron admixtures by influencing said solution with ammonia; stage of separation of precipitated aluminium hydroxide, at which obtained is semi-product in form of said hydroxide with simultaneous obtaining of residual solution of ammonium sulphate, formed at stage of precipitation; stage of obtaining solid ammonium sulphate and stage of thermal decomposition of solid ammonium sulphate, at which obtained is ammonium hydrosulphate and ammonia, applied respectively at opening stage ain preparation of solution-reagent and at stage of precipitation.

EFFECT: invention makes it possible to process any alumina-containing raw material at low temperatures with simultaneous reduction of energy consumption, reduce loss of reagents and required volume of their replenishment in the course of circular process realisation.

26 cl, 2 dwg, 1 tbl, 36 ex