Banca de DEFESA: ELIAS COSTA DE SOUZA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE : ELIAS COSTA DE SOUZA
DATA : 31/01/2019
HORA: 08:30
LOCAL: RNP - Centro de Convivência (Campus Central)
TÍTULO:

PRODUCTION, CHARACTERIZATION AND UTILIZATION OF Eucalyptus urograndis COAL ACTIVATED WITH H₂O₂ AND HNO₃

PALAVRAS-CHAVES:

Adsorption, heavy metals, hydrogen peroxide, biosorbent

PÁGINAS: 52
GRANDE ÁREA: Ciências Agrárias
ÁREA: Recursos Florestais e Engenharia Florestal
SUBÁREA: Energia de Biomassa Florestal
RESUMO:

Activated carbon is an important product, used in several areas, with the most diverse applications, among them we can highlight its environmental application, acting in the remediation of impacts caused by industries, among others. The aim of this work was to perform the oxidation and characterization of Eucalyptus urograndis carbon, oxidized with hydrogen peroxide (H2O2) and to test them in the removal of heavy metals in aqueous solution, by performing a thermodynamic study of the adsorption process. Wood discs of a five-year-old Eucalyptus grandis x Eucalyptus urophylla hybrid were used to make the carbonizations. After charring, part of the material was oxidized on a magnetic stirrer at 80 °C for 4 h using 30% H₂O₂. Then, the characterization (TG-DTG, XRD, MEV and CHNS-O) of the oxidized carbon was performed, after, adsorption kinetics were performed in aqueous medium using a synthetic solution of Cu (II), analyzing pH of the solution and the mass of the adsorbents. Finally, the Langmuir and Freundlich isotherms were prepared for both a single metal system (Cu) and a system with a mixture of metals (Cu, Ni, Cd) at concentrations ranging from 50 to 250 ppm. The adsorbent oxidized with H₂O₂ reached the adsorption equilibrium with only 30 seconds in the system tested. The ideal adsorbent mass found was 0.4 g. The best adsorption capacity of the oxidized adsorbent was 263.77 mg.g^-1 for the experimental values and 235.77 mg.g^-1 for the value calculated by the Langmuir model. The most ideal adsorption isotherm model applied was Langmuir, with a correlation coefficient of 0.9976 for the oxidized carbon. In a system containing 3 different metals, the total adsorption capacity of the oxidized carbon was equal to 305.35 mg.L^-1 for the experimental values and 270.91 mg.g^-1 for the values calculated by the Langmuir Isotherm. It was observed that the adsorption affinity follows the sequence: Cu>Cd>Ni. Eucalyptus urograndis carbon oxidized with H₂O₂ proved to be efficient for removal of heavy metals from aqueous solutions and the total adsorption capacity increases when the adsorbent is used in a system containing more than one metal. The oxidation caused morphological changes in the charcoal, thus favoring its adsorption capacity.

MEMBROS DA BANCA:
Presidente - 1079298 - ALEXANDRE SANTOS PIMENTA
Externo à Instituição - PEDRO NICÓ DE MEDEIROS NETO - UFCG
Interna - 1979301 - RENATA MARTINS BRAGA