Cellulose (Mangifera indica) modified by melamine-silica applied in the treatment of effluents with chemically assisted precipitation
DOI:
https://doi.org/10.33448/rsd-v10i6.15331Keywords:
Mangifera indica; Cellulose; CEPT; Methylene Blue; Adsorption.Abstract
The present work aimed to develop a composite based on cellulose, melamine and silica. Cellulose was obtained from the pruning residues of Mangifera indica for the chemically assisted primary treatment of effluents from the textile industry. The composite was characterized by FT-IR, SEM, TEM, TGA-DTG and Zeta Potential. The central composite planning was applied to optimize the composite mass and contact time in removing methylene blue. FT-IR showed that the composite presented the band for melamine at 815 cm-1. SEM and TEM revealed that on the composite surface there is melamine nitrogen, silicon and sodium from the catalyst. TGA-DTG showed that the composite is thermally more stable than cellulose, with 65% degradation. Due to the zeta potential, pH values above 5 provide greater stabilization and increase the anionic character of the composite. It was chosen as the best condition for the application 60 mg of composite and 30 minutes of contact time, with removal of 88.6 ± 3.5% of the methylene blue. The pH study revealed that above 5, the composite is more efficient. The dye adsorption process by the material was consistent with the Langmuir model (R2 = 0.9921). Thus, the cellulose-melamine-silica composite developed was effective in removing the methylene blue dye, presenting itself as a low-cost, biodegradable and efficient material, with potential for application in the treatment of effluents from the textile industry.
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Copyright (c) 2021 Jarbas Soares de Mesquita Júnior; Francisco Cardoso Figueiredo; Evânia Carvalho dos Santos; Darlisson Slag Neri Silva; José Ribeiro dos Santos Júnior
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