Serpentine is a versatile mineral family rich in Mg silicate with several polymorphic phases, mainly antigorite and lizardite, all of them with similar chemical composition (Mg 3 Si 2 O 5 (OH) 4 ). Their structures are generally composed of octahedral layers rich in Mg[MgO 2 (OH) 4 ] 6− , attached to a tetrahedral silicate [Si 2 O 5 ] 2− sheet. The unique physicochemical properties of serpentinites and the existence of large reserves in Brazil create new important opportunities for research and technological applications. In this work, serpentinites structures and properties are reviewed, as well as its occurrence and literature describing its applications in construction/ceramics, agriculture, as a silica source, in steel production, as an additive/filler in polymers, in the production of composites, adsorption of cations and organics contaminants, CO 2 capture and catalysis. The presence of harmful chrysotile associated with serpentinites, some of its properties and uses are also described.

The present study reports the synthesis and characterization of complexes formed among humic (HA) and fulvic acids (FA) derived from poultry wastes and ions Cu 2+ , Fe 2+ and Zn 2+. The release of such metals in a buffer solution simulating the soil solution was also evaluated. After complexation, the Fourier transform infrared (FTIR) spectra presented alterations in the absorption bands related to changes in the humic structure, thus indicating the complexation with phenolic and carboxylic groups. Thermogravimetric analyses demonstrated that complexed metals decreased the thermal stability of humic substances. Analyses by atomic absorption spectroscopy (AAS) demonstrated that the release of metals is directly related to the origin of the sample, type of interaction of metal and humic structure and conditions of the medium in which the complex is inserted.

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