Adsorção do chumbo na Manihot Esculenta (mandioca) exposta ao rio cateté-pa contaminado por metais pesados

Abstract

In this work, the study site is monitored by an environmental monitoring group, due to the release of effluents from the mining enterprise located near the Cateté River, which belongs to the region of Carajás, Southeast of the State of Pará, where along this river were chosen two points to be studied, the port of the Cateté Indigenous Village and the port of the Djudjeko Indigenous Village. With this, investigating the routine of the population that inhabits this area and uses this port, it was noticed that it is a characteristic of the Indians of the region to use the river for the production of cassava flour (manihot esculenta), food very consumed by them. However, from the confirmations of analyzes of the waters of the Cateté River, carried out by the monitoring team, they indicate that it is contaminated by lead. The study in question addresses the phenomenon that occurs in the stage of production of flour carried out with the aid of the river, the stage of softening, where the cassava is immersed in the waters of the river for a certain period for its softening. Therefore, this work proposes to translate this phenomenon through the development of a mathematical model that numerically describes the process of adsorption of lead by cassava exposed to the Cateté River. For chemical analyses, samples of river water, cassava, cassava flour and sludge formed on the river bank were prepared. Then, after identifying the lead levels in these samples, an algebraic model was created in which the union of the sigmoidal model and the Laplace transform was applied to solve the ionic charge balance. Thereby, simulations were performed for both models, including the extrapolation simulation, in which it is possible to observe the maximum adsorption point. Finally, the model obtained met the objective proposed in this work, being able to characterize and represent the phenomenon of adsorption of lead in the contamination of cassava (manihot esculenta) exposed to water from the Cateté River, concluding that the contamination of the tuber occurs by the concentration of lead deposited in the sludge on the banks of the river.