Influence of physical/chemical treatments to delamination of nanohybrid kaolinite-dipicolinate

Autor(es)

da Silva, Adrieli Cristina ^[1] ; Ciuffi, Katia J. ^[1] ; dos Reis, Marcio Jose ^[1] ; Calefi, Paulo Sergio ^[1] ; de Faria, Emerson Henrique ^[1]

Afiliação do(s) autor(es)

^[1] Univ Franca, GPMatLam, UNIFRAN, Grp Pesquisa Mat Lamelares Hibridos, Av Dr Armando Salles Oliveira 201, Parque Univ, BR-14404600 Franca, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: APPLIED CLAY SCIENCE; v. 126, p. 251-258, JUN 2016.
• Citações Web of Science: 4

Resumo

This work shows how submitting kaolinite grafted with dipicolinic acid (Kaol-dpa) to treatment with different solvents and physical/chemical treatment (e.g., ultrasound bath, magnetic stirring, or thermal treatment in water) influences Ka-dpa delamination. X-ray powder diffraction, chemical analysis (C, H, and N), thermal analysis, Fourier-transform infrared spectroscopy, and transmission electron microscopy aided examination of all the samples. Delamination of the treated Kaol-dpa samples elicited changes in the intensity of the characteristic Kaoldpa d(001) reflections. Treatment with different solvents reduced the intensity of the d(001) reflections, which almost disappeared for the sample treated with water suggesting the exfoliation. Ultrasound bath, thermal treatment, and magnetic stirring in water also decreased the typical Kaol-dpa d(001) reflection and increased the reflection at 2 theta = 12.2 degrees, the reflection due to the basal spacing of purified kaolinite. Long treatment times eliminated the dipicolinic acid that was only adsorbed onto Kaol-dpa nanohybrid. In conclusion, different types of physical treatment in water were able to delaminate Kaol-dpa, thereby exposing the reactive pyridine-carboxylic groups present in the hybrid matrix. (C) 2016 Elsevier B.V. All rights reserved. (AU)

• Processo FAPESP: 13/19523-3 - Materiais biohíbridos funcionais baseados em argilas lamelares e/ou fibrosas com aplicações multifacetadas
• Beneficiário: Emerson Henrique de Faria
• Modalidade de apoio: Auxílio à Pesquisa - Regular