An improved process to benefit colemanite and/or howlite minerals comprising the stages of: treating mineral with sulfuric acid in order to dissolve boron compounds; separating the solution formed from the solids in suspension; reacting said solution with hydrogen sulfide in order to precipitate the arsenic and iron impurities contained in the solution, and separating the impurities precipitated from the remaining solution as a beneficiated colemanite with boron. Said solution of the beneficiated colemanite with boron can be dried by spray fluidizing in order to obtain solid beneficiated colemanite with boron or said solution can be reacted with calcium hydroxide to precipitate a beneficiated colemanite with calcium borate which is separated from the remaining solution. This can be recycled for treatment with sulfuric acid to concentrate the mineral. PPThe beneficiated colemanite with precipitated calcium borate, can be reacted with sulfuric acid in order to separate gypsum from the solution, while evaporating the remaining solution to precipitate boric acid. Said evaporation could be partial, while recycling the remaining solution to the evaporation stage to concentrate the boric acid.
展开▼
