Zeólita 4A crescida sobre fibra cerâmica para o abrandamento de águas

Abstract

Zeolites constitute a special class of microporous materials with a structure composed of well-defined pore systems, which have high chemical stability and high cation exchange capacity. These properties make them materials with high potential for water softening processes, in which Ca²⁺ and Mg²⁺ ions are removed. However, due to the polycrystalline nature of these materials, i.e., their powdered form, most of their applications demand compaction in the form of, for example, pellets, which leads to restrictions on mass transfers that compromise their performance. Among the strategies that emerge as alternatives to overcome these barriers, it is worth mentioning the hierarchy of zeolitic structures, which can occur from their growth on preformed structures. In this work, 4A zeolite was crystallized on the rock fiber surface, generating a microporous material with hierarchical characteristics. The characterization was carried out using Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) techniques. The evaluation of the performance of the material in terms of its softening capacity was carried out through column tests using Ca²⁺ and/or Mg²⁺ solutions. The results obtained indicated that the synthesis of the material was successful, with the characteristics of zeolite 4A preserved and crystals well distributed over the fiber structure. The hierarchical zeolite was efficient in the softening processes and showed significant regeneration capacity.