PALYGORSKITE FROM PIAUÍ, BRAZIL: TECHNOLOGICAL INVESTIGATION OF A NEW MINERAL OCCURRENCE WITH INDUSTRIAL AND ENVIRONMENTAL APPLICATIONS

Palygorskita do Piauí, Brasil: investigação tecnológica de uma nova ocorrência mineral para aplicações industriais e ambientais

Abstract

This research reports the technological investigation of a run-of-mine sample of palygorskite from a new occurrence in the Guadalupe, state of Piauí, Brazil and consisted of ore dressing of the sample and wet size classification in 45 and 20 µm, with subsequent wet magnetic selection of the aliquot with particle size smaller than 20 µm. The fractions obtained were characterized by X-ray diffraction, X-ray fluorescence, scanning electron microscopy, cation exchange capacity, surface charge measurement (zeta potential) and analysis of the textural properties of the clay mineral through N₂ nitrogen physisorption using BET surface area determination. According to results this sample consisted of palygorskite, kaolinite, goethite and quartz, had 41 meq 100 g^-1 of CEC, negative surface charge for a pH range of 2.2 to 14, specific area of 142.08 m²g^-1 and average pore diameter size of 52.77 Å. The new occurrence of palygorskite has characteristics for adsorbents and industrial applications.

Keywords: palygorskite, technological investigation, industrial applications.