Estudo cinético comparativo da biossorção de cobre por diferentes biossorventes

Abstract

The different existing industries are important for the development of society, as they manufacture various products necessary for human survival, but these industries use a large amount of water, generating effluents that can be contaminated, for example, with metals, which discharged into water bodies in high quantities, cause problems for fauna, flora and human health. Among the various existing metals, copper stands out, the third most used metal in the world. Wastewater with a high content of this metal prevents the growth and reproduction of organisms and microorganisms and, in addition, the high intake of copper by humans, leads to toxicity, vomits, cramps, convulsions and even death. Thus, effluents containing copper ions must be treated before disposal, respecting current environmental laws. Thus, this work analyzed the copper biosorption by different biosorbents, aiming at a new alternative in the treatment of industrial effluents. Biosorption tests and kinetic study of copper in anaerobic biomass from a UASB reactor, inactivated, in its granular and macerated form were carried out. The FTIR analysis of this biomass presented as functional groups: alcohol, alkane, water, ether and amine. The pseudo–second order kinetic model was the one that best fit the experimental data. Copper adsorption processes in other biosorbents and adsorbents reported in the literature were also analyzed. The biosorbents were: Saccharomyces cerevisiae fungus, Aspergillus niger fungus, brewer's yeast residues, Penicillium cyclopium fungus and sour orange residues and the adsorbents: silica gel, alumina, activated carbon and zeolite. For works with different biosorbents, the kinetic models were applied and for the adsorbents, only the ready-made results of the kinetic studies were analyzed. For the tests with different biosorbents, the model that best suited was the pseudo–second order and for the work that used green algae Scenedesmus abundans, the Elovich kinetic model was the one that showed the best results and for the adsorbents, all fit to the pseudo-second order model. And finally, the granular and macerated biosorbent from a UASB reactor, when compared to other biosorbents, has the same order of magnitude of reaction speed (k2) as the fungus Penicillium cyclopium1 and when compared to the adsorbents, the same order of magnitude of (k2) of zeolite and activated carbon.