The industrial costs of zeolite synthesis can be diminished by the substitution of traditional raw materials by natural sources. In this work, we obtained LTA zeolite from four natural materials, three different diatomites and expanded perlite, and characterize them by X-ray diffraction, X-ray fluorescence and scanning electron microscopy. It was possible to observe the formation of the zeolitic materials through the identification of the Bragg reflections and the cubic morphology characteristic of the aluminosilicate. The Si/Al ratio of the samples resulted next to the unit as expected for this topology. We found small differences between the zeolitic products, remarking the possibility of adapting this process using natural materials to industry. These results were used for the Green Star evaluation, calculating the synthesis degree of greenness, resulting greener due to the complete substitution of the traditional silica source.

Diatomites are natural materials that are easily found around the world and require further study to achieve a systematic application in industry. In this study, we compared three Brazilian diatomites from different locations and found some similarities in their intrinsic characteristics that may be useful for removing contaminants, such as rhodamine B and methylene blue. The samples were analyzed by X-ray diffraction, X-ray fluorescence, microscopy, thermogravimetry and mercury intrusion-extrusion porosimetry. Our findings on their porous structures were very interesting and explain their different behavior when adsorbing different dyes, thus, establishing a direct relationship between diatomite structure and application.