After the environmental disasters generated by the tailings dams of the iron mineral industry in Mariana (2015) and Brumadinho (2019) in Minas Gerais, the urgency of studies to know their chemical and mineral properties, as well as their conversion into low-cost value-added products, thereby reducing their disposal and environmental pollution. As in Minas Gerais, the state of Pará has several tailings dams (iron, manganese, copper, aluminum, kaolin, nickel, gold, silicon) along its territory, most of which have no knowledge of their properties. mineral chemistry. In this work, a characterization study of bauxite (aluminum) washing tailings from the Amazon (West Pará) was developed for the production of anionic clays, also called layered double hydroxides (HDLs). These materials are known for their technological importance for environmental clean-up, slow and controlled release of fertilizers and agrochemicals, adsorbents, ion exchangers and catalysts. In relation to the bauxite washings tailings, they were successfully transformed into nanomaterials of piroaurite (Mg / Fe) and hydrocalumite (Ca / Fe) type HDLs, as well as Katoita (Ca / Al / Fe) minerals. It is described in the literature, thus showing that an unwanted product in the mineral industry can be used as an interesting low-cost raw material for the production of materials of great technological relevance, with a possible advantage in reducing its environmental impacts in the Amazon. A sciometric study was carried out to map the panorama of HDL production and application in Brazil. The results revealed that the major research centers that work on HDLS are in the South and Southeast.
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