Alternatives for the production of Potassium Fertilizers in Argentina

Abstract

The use of potassium fertilizers on crops brings with good yields of crops and maximum profitability for farmers. Currently in Argentina, the level of production of potash fertilizers does not cover the needs of the sector making it necessary to import to meet demand. On the other hand, the brines of the Puna, which are exploited to produce lithium carbonate, contain potassium chloride in appreciable concentrations and could be an alternative resource to obtain potassium fertilizer. The aim of this paper is to analyse the possibilities of obtaining potassium fertilizers in the NOA, using both, natural brines and process effluents of obtaining lithium carbonate. Industrially, KCl is obtained by froth flotation and fractionated crystallization. Nowadays, salting-out is not applied industrially to obtain KCl. Through salting-out, KCl crystallization is achieved by adding an organic solvent that modifies KCl solubility. In this work, the three techniques mentioned are compared, focusing on performance, recovery and purity of the crystals obtained. The solids obtained by flotation have purity between 85-90% while by fractionated crystallization the purity of the solids is higher than 95% as in the crystals obtained by salting-out. These results show that the KCl obtained can be used as a fertilizer since it meets the specifications for use as such.