Metal-organic frameworks (MOFs) based on Calcium-terephthalate(Ca-MOFs) were synthesized by the sonochemical method and applied to remove methylene blue (MB) from an aqueous solution via adsorption. The samples were prepared and characterized by X-ray Powder Diffraction (PXRD), Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (ATR-FTIR), Thermal Analysis (TGA-DTA), and Scanning Electron Microscopy (SEM). The studied of the effect of the synthesis temperature on the crystallization of MOFs indicated two different crystal structures were identified, Ca(BDC) and Ca(BDC)(H2O)3. Observed that samples with a higher proportion of the Ca(BDC) phase showed greater dye adsorption capacity. The experimental data fit the pseudo-second-order kinetic model. The Langmuir and Freundlich adsorption models were applied to describe the equilibrium isotherms, and the isotherm constants were also determined. The adsorption equilibrium data preferably fit the Freundlich model. The samples were applied to methylene blue adsorption at pH 5.6, with maximum adsorption of 60.241 μmol.g-1 and high reuse efficiency, reaching 97% of the initial adsorption capacity in the second reuse cycle.

Resumo O presente artigo traz uma revisão da principal literatura produzida pelo Grupo de Estudos Arqueométricos do Instituto de Pesquisas Energéticas e Nucleares, Comissão Nacional de Energia Nuclear, de São Paulo (IPEN-CNEN/SP), criado em 1997, como consequência de uma iniciativa internacional para motivar o uso de técnicas nucleares para caracterização de materiais arqueológicos. Desde aquele momento, e até hoje, o grupo tem desenvolvido parcerias com pesquisadores/as de diferentes regiões do Brasil e de outros países para oferecer subsídios à compreensão interdisciplinar das cadeias operatórias de produção da cerâmica. Além disso, também vem aportando dados para o estudo multielementar e mineralógico de depósitos arqueológicos. Ao descrever brevemente os princípios das técnicas empregadas e a síntese dos resultados obtidos para cada estudo de caso, o objetivo foi demonstrar a contribuição das análises físico-químicas para questões relacionadas a aspectos culturais, como escolhas tecnológicas compartilhadas, redes de trocas e interações sociais em diferentes períodos do passado.

Abstract The present paper brings together key literature produced by the Group of Archaeometric Studies of the Nuclear and Energy Research Institute, IPEN – National Nuclear Energy Commission (São Paulo, Brazil). This group was founded in 1997, as a result of an international initiative to encourage the use of nuclear techniques for the characterization of archaeological materials. Since then, the Group has developed interdisciplinary partnerships with researchers from Brazil and other countries to offer analytical tools for unraveling ceramic chaîne opératoires in different contexts. Such studies have contributed towards wider cultural interpretations regarding shared technological choices and artifact exchange networks in different social groups. Recently, the Group has also used multi-elemental and mineralogical techniques to tackle questions over the formation of archaeological deposits. This paper briefly explains the analytical principles of the employed techniques, and emphasizes how the results of each case study contribute to the interpretation of specific archaeological problems.