Mineralogy and chemistry of a new bentonite occurrence in the eastern Amazon region, northern Brazil

The Brazilian production of bentonite is approximately 300,000 t/year, with more than 88% of this production concentrated in small deposits located in the Paraíba state (northeast Brazil), which consequently are becoming exhausted. The objective of this paper is to present a new occurrence of bentonite from the eastern Amazon in northern Brazil, here referred to as Balsas bentonite. A selected sample of the material was characterized by XRD, TG/DTA, ICP-OES, FTIR, SEM-EDS, N2 adsorption/desorption at 77 K and CEC. The main constituent of the bulk sample is montmorillonite. Kaolinite is completely absent, in contrast to some bentonites found in the famous Paraíba state. The results obtained from the mineralogical and chemical characterization confirm that this material, in comparison to some reference bentonites from the Clay Mineral Society Source Clays, has promise as an engineering material, indicating its possible use in various research and industrial applications.