Basic Treatment in Natural Clinoptilolite for Improvement of Physicochemical Properties

DE SOUZA, VANESSA; VILLARROEL-ROCHA, JHONNY; DE ARAÚJO, MARIA; SAPAG, KARIM; PERGHER, SIBELE

Minerals

MDPI

Lugar: Meolbourne; Año: 2018 vol. 8

Natural zeolites are low in cost and exhibit interesting properties for applications inadsorption and catalysis. However, the fact that they are natural materials, not obtained in pureform, and can incorporate various compensating ions can compromise their properties and restricttheir use. As their textural and chemical properties are of great relevance for adsorption and catalysisapplications, this work aims to study the modification of the natural zeolite clinoptilolite to obtainmaterials with better physicochemical properties. Clinoptilolite was treated with NaOH undervarious conditions. The treated material was characterized by X-ray diffraction, X-ray fluorescence,N2 adsorption and desorption at 77 K, CO2 adsorption at 273 K, and pyridine adsorption. The treatmentallowed the removal of silicon from the material, improving the textural properties and preservingthe structural Al. With the removal of Si, the Si/Al ratio decreased, and consequently, the number ofacid and adsorptive sites increased. In addition, statistical planning revealed that the concentration ofNaOH is the parameter that most influences the improvement of the textural properties.