Abstract

This innovative research aimed to study the potential of the use of solid wastes from cassava root processing industry (Manihot esculenta Crantz) (peel, bagasse and the mix peel + bagasse) as natural adsorbents of Cr³⁺ from waters. In a first step, the biosorbents were characterized chemically, structurally and morphologically. This way were performed infrared spectrum analysis, scanning electron microscopy, point of zero charge and chemical composition for all studied natural adsorbents. After that, studies evolving kinetics, equilibrium, thermodynamics and desorption of Cr³⁺ were performed. According to the obtained data the cassava adsorbents proved to be efficient in the removal of Cr³⁺, being found in Langmuir and D-R models the best fitting, indicating monolayer chemisorption, with endothermic character. The cassava materials presented lower rates of desorption also suggesting a chemisorption of Cr³⁺ molecules. By the obtained results it was concluded that the use of cassava biosorbents are viable for the decontamination of waters containing Cr³⁺, being the use of cassava wastes for adsorption a complementation of the final steps of cassava productive chain. 

Key words: Contamination of waters, chromium toxicity, biosorbents, natural adsorbents, remediation of waters, biosorption, decontamination of water.