Abstract

MONCADA, Fidelina; OBANDO, Yaneis  and  PARRA, Frank. Crystallization of the potassium sulfate by means of the reaction of the phosphogypsum and sylvite by amoniation in a batch cristallizer. Rev. Téc. Ing. Univ. Zulia [online]. 2007, vol.30, n.Especial, pp.472-478. ISSN 0254-0770.

The purpose of the work was to determine the best conditions of reaction for the production of crystals of potassium sulphate from phosphogypsum and sylvite in aqueous ammonia. The phosphogypsum used was obtained from the phosphoric acid plant of Pequiven-Morón. With this aim, a method was developed in which the variables were varied in a certain rank to study: temperature, concentration of the aqueous ammonia solution, ratio of gypsum to solvent in reactor charge and grain size of phosphogypsum. It was obtained that the best conditions of reaction for the production of potassium sulphate are: temperature of reaction 5°C; the crucial factor in the system studied is the effect of the ammonia which both promotoes the formation of potassium sulphate and also hinders its conversion to syngenite, the initial solvent composition 32% by weight ammonia in water; weight ratio of gypsum to solvent of 1:5 and size of 75 smaller grain of mehs.

Keywords : Potassium sulfate; crystallization; phosphogypsum; sylvite.