Banca de DEFESA: ICARO MYCHEL GOMES LEITE DE SA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : ICARO MYCHEL GOMES LEITE DE SA
DATE: 23/07/2021
TIME: 08:30
LOCAL: Google Meet
TITLE:

Synthesis of Fe3O4/HDL-MgAl magnetic composite for adsorptive removal of malachite green in aqueous medium

KEY WORDS:

Layered Double Hydroxide; magnetic adsorbent; composite; emerging pollutants; wastewater treatment.

PAGES: 76
BIG AREA: Ciências Exatas e da Terra
AREA: Química
SUBÁREA: Físico-Química
SUMMARY:

The detection of pollutants in wastewater, groundwater and surface water and the growing demand for higher levels of supply have led the scientific community to seek new efficient water treatment methodologies to remove such compounds. Several methodologies have shown to be promising, among which, adsorption, a technology used efficiently for the removal of pollutants. Many studies have sought to develop new adsorbent materials capable of being regenerated and reused during several cycles. Double Lamellar Hydroxides (LDHs) already have a well-established role in studies aimed at removing pollutants via adsorption, on the other hand, their association with other materials has aimed to reduce some disadvantages of this material, as for example, the final adsorbent/solution separation process. In this study, LDH was synthesized by associating itself with magnetite, giving magnetic properties to the adsorbent. This effect allows the reduction of material losses during the adsorptive processes, as well as an easy and quick post-treatment recovery, without the need for centrifugation. The Fe3O4, LDH-MgAl and Fe3O4/LDH-MgAl composite synthesized were characterized via Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), X-Ray Diffraction (XRD) and Raman Spectroscopy, adsorption/desorption N2 by the BET method and Zero Charge Potential (ZCP). Malachite green was used as a model pollutant, reaching qe values qe of 198.94 and 172.13 mg g-1 for LDH-MgAl and Fe3O4/LDH-MgAl, respectively. Furthermore, for the three materials, the pseudo-first order model, in the kinetic study, was the one that best fit the experimental data. Furthermore, through the adsorption isotherm data, a better adherence to the Sips model was observed, compared to the other models used in this study. Although LDH-MgAl and the composite (Fe3O4/LDH-MgAl) have shown excellent efficiency for removing the pollutant, the difference was in the operational process, where for LDH-MgAl the removal of the adsorbent required centrifugation and/or filtration, already for Fe3O4/LDH-MgAl, the removal was performed with the application of a magnetic field that concentrated and trapped the adsorbent at the bottom of the reactor. 

BANKING MEMBERS:
Presidente - 1314677 - CARMEM LUCIA DE PAIVA E SILVA ZANTA
Interna - 1869296 - CINTYA D'ANGELES DO ESPIRITO SANTO BARBOSA
Externo ao Programa - 013.808.764-43 - JOSÉ LEANDRO DA SILVA DUARTE - UFAL