Biossorção de crômio hexavalente por biomassa fúngica e bacteriana

• Autor(a) principal: Ferreira, Glalber Luiz da Rocha
• Data de Publicação: 2016
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UFG
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/6711
• topic: Metais pesados; Cr(VI); Crômio hexavalente; Biossorventes; Biossorção; Heavy metals,; Hexavalent chromium; Biosorbents; Biosorption; CIENCIAS BIOLOGICAS::MICROBIOLOGIA

The existing techniques for removing heavy metals are expensive and are often not effective. Thus the application arises from biosorbents, an emerging technology that needs to be studied and explored, in order to promote better environmental and human life quality. The study craved verify removal capacity in synthetic aqueous solutions of ions Cr (VI) at concentrations of 10, 25, 50, 75, 100, 125 and 150 mg/L by biosorption by use of active and inactive fungal biomass Pleurotus ostreatus. In the use of the active biosorbent, kinetic studies revealed that in 336 hours was achieved 100% of its saturation capacity at concentrations of 10 and 25 mg/L of Cr (VI), achieving total removal of Cr (VI) in the order of 250 times over the recommended limit for industrial effluents in CONAMA Resolution nº 430/2011, and 360 hours biomass reached its maximum capacity of saturation, reaching values of 98,18% and 96,84%, in concentrations of 50 and 75 mg/L of Cr (VI), respectively. Observing the concentrations of 100% removal was confirmed by analysis of the total EAA chromium values of 141,66 mg/g and 133,55 mg/g biomass respectively. The analysis revealed the micrographs by SEM and TEM we observed at the cellular composition of biomass the presence of bacterial cells associated with the fungus, which on analysis was not possible to know where the metal was in adsorbed, it is better to point out that it was possible to detect content chromium from the cellular structure of the biomass. In the use of the idle biosorbent, kinetic studies showed that 6, 10 and 12 minutes it was reaching 100% of its saturation capacity at concentrations of 10, 25 and 50 mg/L of Cr (VI), respectively, achieving total removal Cr (VI) in the order of 500 times over the recommended limit for industrial effluents in CONAMA Resolution No. 430/2011, and in 22 minutes biomass reached its maximum capacity of saturation, reaching values of 73,21% and 55,13% at concentrations of 75 and 100 mg/L of Cr (VI), respectively. The Langmuir model was the one that best fit the experimental data biosorbent P. ostreatus, when evaluating the separation factor (RL), responding to values between zero and 1. Now, considering the values of the coefficient of determination (R2), the Freundlich model fit better due to present higher values in relation to the Langmuir model.