Produção de material zeolítico a partir de caulim da Amazônia em escala semi piloto: aplicação na adsorção de cobre

Abstract

This work aims to synthesize a zeolite product composed of zeolite type "A" plus sodalite using as filler kaolin starting material. The synthesis of Zeolites was carried out in a short time and in a system with agitation, in a reactor of stainless steel with a volume of approximately 0.001 m3, that is, in semi-pilot scale. The system was heated by steam from a boiler. The X ray diffraction (XRD), X ray Fluorescence Spectrometry, Scanning Electron Microscopy (SEM), Granulometric Analysis and Differential and Gravimetric Thermal Analysis (DTA and TG) were identified and characterized. In the synthesis process the metakaolin was used as the source of silica and alumina, which was obtained at 600 ° C for 2 hours of calcination in a muffle furnace. A 5M sodium hydroxide solution was used as the sodium source. Several syntheses were carried out for a maximum duration of 180 minutes. Every 30 minutes aliquots of the product were taken for the study of reaction kinetics. The results of the zeolite syntheses were satisfactory and the product obtained was applied to the adsorption of Cu2+ ions, in which the influence of the variables: time, temperature, pH and adsorbent quantity were evaluated. The determination of the best adsorption model was performed by the Monte Carlo method via Markov Chain and through the Akaike Information Criterion the isotherms that were closest to the presented results were established. The results obtained were compared with other studies available in the literature and showed significant values, which characterize the process of zeolite production and adsorption as promising and efficient.