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Hydrotalcite-like compounds have been used in catalysis, medicine, environmental chemistry, and other applications. Depending on the metals present, the solids obtained by calcination can be used due to their basicity, memory effect, and high specific surface area. This study describes some characteristics o f hydrotalcites based on Cu- Zn-AL The solids were characterized by AAS, XRD, FTIR, DSC and TGA. In the FTIR spectra it was observed that in the solids with higher copper contents the band signed to O "H stretching (M"OH, H"OH) was moved to lower wave number values, because electron density o f hydroxide groups orients toward the metallic copper center In all materials hydrotalcite phase formation was observed and the Cu(OH)) phase in solids with higher copper content was detected, fact attributed to the Jahn-Teller effect Results indicate that the collapse of the structure occurs at lower temperatures in the case o f solids with higher copper conten! In all the tested materials the decomposition o f the HTLc structure and the formation ofmetal oxides was observed, as well as decomposition o f carbonate ions occluded in the solid dueto the collapse o f the lamellar structure. [ABSTRACT FROM AUTHOR]