Banca de DEFESA: KÁSSIA LENE LIMA MARINHO

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE : KÁSSIA LENE LIMA MARINHO
DATA : 21/12/2020
HORA: 10:00
LOCAL: UFOPA
TÍTULO:

CONVERSION OF MINING TAILING INTO MATERIAL WITH ADSORBENT PROPERTIES OF ORGANIC POLLUTANTS

PALAVRAS-CHAVES:

Tailings, Amazon, Transformation, Clay, Adsorption

PÁGINAS: 76
GRANDE ÁREA: Ciências Exatas e da Terra
ÁREA: Geociências
SUBÁREA: Geologia
ESPECIALIDADE: Mineralogia
RESUMO:

In this work, the transformation of Mn tailings from the Kalunga dam (Pará) into anionic clay with shigaite structure was evaluated, after studies of chemical and mineral characterization of the tailings. For the studies of conversion of tailings into shigaite, the influence of the following synthesis parameters was evaluated: ratio M²⁺: M³⁺, pH, time and temperature. The characterization analyzes involved were X-ray fluorescence, X-ray diffraction, Raman and infrared spectroscopy (FTIR), thermogravimetric analysis, scanning electron microscopy (SEM) and transmission electron microscopy (MET). The results showed that tailings composed of todorokite, lithiophorite, vernadite, cryptomelane, hollandite, birnessite, quartz, cristobalite, anatase, hematite and with an MnO content above 54% (weight) were successfully converted into anionic shigaite clay. The ideal conditions revealed that the material was formed without impurities at 75 ºC, in 24 hours, M²⁺: M³⁺ ratio of 4: 1, pH of 11.2. Stretch bands typical of lamellar product such as shigaite were observed in the 4000 to 400 cm^-1 range. The thermal stability of shigaite was at 200 ºC. A typical morphology in leaves with an average grain size of 0.5 to 2.5 mm was observed. A study of adsorption of methylene blue and methyl orange textile pollutant by synthesized shigaite from the tailings was investigated and the results showed a 45.73 % adsorption capacity of the methylene blue and around 30 % for methyl orange dye. These results show that mining waste can be used as a raw material to obtain materials with interesting technological properties.

MEMBROS DA BANCA:
Presidente - 2142681 - BRUNO APOLO MIRANDA FIGUEIRA
Interno - 2143922 - ISRAEL NUNES HENRIQUE
Externo à Instituição - DORSAN DOS SANTOS MORAES - UFPA