Uso da fibra de calotropis procera funcionalizada para adsorção de corante de efluente têxtil

Abstract

The present study used Calotropis procera fiber as a natural adsorbent for the reactive dye present in textile effluents. The justification for choosing this dye was due to its wide use in dyeing processes on cotton substrates. Due to the lack of affinity of the fiber with water, the fiber was submitted to a functionalization with chitosan, aiming at a better adsorption and interaction between fiber and effluent. The adsorbents used, for the most part, are not biodegradable, which is currently not interesting for the environment, the current search is for environmentally friendly materials. The Calotropis fiber was selected due to its high predominance in the northeast region of Brazil, because it is considered a weed and because it has internal voids that help in the adsorption process, in addition to being biodegradable. The use of chitosan as a functionalizing agent is justified by its non-toxicity, biocompatibility and biodegradability. The fiber characteristics were evaluated with the aid of SEM, FTIR and XRD analysis. The effluent was characterized through the environmental parameters of pH, turbidity, conductivity, dissolved oxygen (DO) and UV-Vis absorbance, these analyzes were performed before and after contact with the fiber. The SEM analyzes demonstrated that Calotropis has a smooth surface, without convolutions and internally hollow, even after its functionalization, the infrared analyzes indicated the presence of carboxylic and hydroxyl groups. The adsorption efficiency was analyzed using the effluent generated by dyeing with reactive dye BLUE BG-R CONC, obtaining a removal of 100%. The results showed that Calotropis procera functionalized with chitosan is suitable for the adsorption of reactive dye, being a simple alternative, environmentally correct, being a potential method for removing color from textile effluents, contributing to the preservation of the environment.