Sodificación de la zeolita del yacimiento "Tasajeras" a escala de planta piloto

Abstract

Towards the end of the eighties it was demonstrated that the sodium molar equivalent fraction in the HEU and MOR zeolites types has to be greater or equal to 0,8 mEq/g in order to avoid other products formation during hidrothermal transformation process of them into FAU type. Subsequently it was shown the possibility of synthesizing LTA zeolite starting from the FAU zeolite washing liquors in case the last one is gotten very pure. In this way, the possibili ty of synthesizing LTA zeoli te by an economically viable procedure appears but it requires of an efficient exchange of starting material. In this paper the exchange of zeolite from "Tasajeras" Deposit with sodium in a fl.uidized bed reactor was studied by means of a 2² factorial experimental design. The influence of sodium concentration and pH of the solution over molar fraction of sodium in mi­neral and effective diffusion coefficient and crystal square radius relation were evaluated. It was established that the equivalent molar fraction of sodium in the mineral <loes not depend on its solution concentration [14-18 % (p/p)] or pH (7-9). Likewise, it was observed a dependence between effective coefficient and crystal square radius relation and above mentioned varia­bles The most significant ofthem was the sodium concentration in exchange solution.