| Summary: | Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-03-09T23:10:26Z
No. of bitstreams: 1
JoaoLeonardoFreitasOliveira_DISSERT.pdf: 3296758 bytes, checksum: 105b144fc3affbe55e42b5df17981966 (MD5) === Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-03-11T19:57:37Z (GMT) No. of bitstreams: 1
JoaoLeonardoFreitasOliveira_DISSERT.pdf: 3296758 bytes, checksum: 105b144fc3affbe55e42b5df17981966 (MD5) === Made available in DSpace on 2016-03-11T19:57:37Z (GMT). No. of bitstreams: 1
JoaoLeonardoFreitasOliveira_DISSERT.pdf: 3296758 bytes, checksum: 105b144fc3affbe55e42b5df17981966 (MD5)
Previous issue date: 2015-01-26 === Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES === As argilas s?o materiais com propriedades particulares que as tornam promissoras para
diversos estudos. Neste trabalho foi utilizada a argila vermiculita como suporte para
compostos de ferro, com intuito de obter materiais promissores para aplica??es no
processo do tipo foto-Fenton heterog?neo. Ao todo, o estudo contou com seis s?lidos,
partindo da vermiculita (V0) obteve-se a vermiculita calcinada (V0-C), o material misto
(V0/?-FeOOH) formado por vermiculita mais akaganeita, vermiculita trocada (V0t-C),
vermiculita impregnada por via ?mida (V0u-C) e a V0u-CL que representa o s?lido obtido
por impregna??o com uma posterior lavagem. Os s?lidos do estudo tiveram suas
caracter?sticas f?sico-qu?micas investigadas pelas seguintes t?cnicas de caracteriza??o:
Difratometria de Raios-X (DRX), Espectroscopia de Infravermelho (IV), Espectroscopia
de Energia Dispersiva (EDS), Fluoresc?ncia de Raios-X (FRX), UV-Vis por Reflect?ncia
Difusa (UV-Vis RD), An?lise Termogravim?trica (TGA) e Microscopia Eletr?nica de
Varredura (MEV). O material V0 apresentou tr?s fases distintas, sendo estas, a pr?pria
vermiculita, hidrobiotita e biotita, as duas ?ltimas fases fazem parte do processo
geol?gico de forma??o da vermiculita. Os s?lidos obtidos ap?s as modifica??es
apresentaram aumento na quantidade de ferro presente na argila, sendo estas quantidades,
importantes para aplica??o em rea??es do tipo foto-Fenton. As micrografias e os dados
de EDS, demonstram que ap?s os tratamentos de adi??o do metal, o ferro foi intercalado
na estrutura da vermiculita para os s?lidos V0t-C e V0u-C, no entanto, o mesmo n?o
ocorreu com material misto. No processo foto-Fenton, observou-se uma remo??o m?xima
de 88,8% da colora??o do corante azul de metileno para o catalisador V0/?-FeOOH,
enquanto que para os outros s?lidos obteve-se valores entre 76,8 e 62,6%, contra apenas
37,8% de descolora??o sem presen?a de catalisador. Portanto, conclui-se que a argila
vermiculita apresenta-se como um bom catalisador e suporte para o ferro, al?m de
apresentar um baixo custo devido sua elevada abund?ncia. === Clays are materials with specific properties that make them promising for various studies.
In this work we used the vermiculite clay as support for iron compounds, in order to
obtain promising materials for application in the heterogeneous type photo-Fenton
process. In all, the study included six solid, starting from the vermiculite (V0) was
obtained calcined vermiculite (V0-C), the mixed material (V0/?-FeOOH) formed by
vermiculite more akaganeite, exchanged vermiculite (v0t-C), vermiculite impregnated
Wet (V0u-C) and V0u-CL that is the solid obtained by impregnating with a back washing.
The solids of the study had their physical and chemical characteristics investigated by the
following characterization techniques: X-Ray Diffraction (XRD), Infrared Spectroscopy
(IR), Energy Dispersive Spectroscopy (EDS), X-Ray Fluorescence Spectroscopy (XRF),
UV-Vis by Diffuse Reflectance (DR UV-Vis), Thermogravimetric Analysis (TGA) and
Scanning Electron Microscopy (SEM). The V0 material showed three distinct phases,
which are the very vermiculite, hidrobiotite and biotite, the last two phases are part of the
geological of formation process vermiculite. The solids obtained after the modification
showed an increase in the amount of iron present in the clay, these being quantities
important for application in photocatalysis. The micrographs and EDS data, show that
after treatment of addition of the metal , the iron was intercalary in structure of vermiculite
for solid V0t-C and V0u-C, however, this did not occur with mixed material. In the photoFenton
process, was observed a maximum removal of 88.8% of the dye methylene blue
coloring for the catalyst V0/?-FeOOH, while for the other solids was obtained values
between 76.8 and 62.6%, compared to 37.8% of discoloration without the presence of
catalyst. Therefore, it is concluded that the vermiculite clay presents as a good catalyst
and iron support for the, beyond of presenting a low cost because of its high abundance.
|
|---|
