CONTROL OF IMPURITIES FOR COPPER ACID LEACHING SOLUTIONS. PART I: SOLUBILITY IN WATER AT SEVERAL TEMPERATURES AND SEVERAL NaCl CONCENTRATIONS OF DOUBLE HYDRATED SULPHATE ALUMINIUM-POTASSIUM SALT

摘要

SKM has a line of research for control of impurities in acid copper leaching solutions since two years ago. This line of research has been developed and several articles have been published. It is a second layer of information generated in order to solve the problem of aluminum high concentration inside the Copper leaching solution (both, inorganic and bioleaching). On a first attempt a KCl salting out process was developed by Rivera et al. [1] , but KCl has a high commercial price and the process, nevertheless technically well done, could not be economically supported. The idea then was to find out another process in order to recover potassium and get it back in an infinite cycle once and again into the process. This paper is the first of a series of three. This paper, the first one shows the solubility of Al2K2(SO4)4*24H2O. The second paper shows how NaCl is totally necessary in order to have a middle step with production of Na2SO4 and liberation of Cl- anion for later recovery of KCl(8), also presented in this congress . The third paper will finally show how KCl can be finally recovered, solving the problem of expensive supply, and the original problem, high aluminium concentration in copper leaching solutions. The third paper will be presented next year.