Utilização do carvão de pneus inservíveis para remoção do corante azul de metileno

Abstract

The discarded tire is a waste that presents a range of chemical compounds in its structure, which can cause damage to the environment and public health when not properly disposed. The tire collection and disposal system was established by law,which highlighted the manufacturer ́sresponsibilities. Thus, pyrolysis emerged as an efficient alternative in reverse logistics. At the end of this process, about 46% of the tire's weight consists of coal. The destination of this material, combined with the production of a low-cost adsorbent, emerges as an innovation in the remediation of industrial effluents, as it solves the problem of the disposal of a polluting waste and helps in the preservation of water bodies. Thedescardedtire coal was provided by a company in the industry that performs the complete pyrolysis of the tire. The preparation of coal for adsorption followed the standardization of the material with a set of sieves, acid demineralization (HCl), activation with water vapor, physico-chemical and spectroscopic characterization and evaluation of the adsorption potential: kinetics, isotherms and thermodynamic parameters. For the studies of adsorption a synthetic solution of methylene blue (AM) was used, due to its great applicability in the industry and consecutively in the remnants of the processes to which it is used. The results reveal 80% carbon for crude coal (CVB) and 85% for demineralized and activated coal (CVDA). It was found that demineralization eliminated inorganics such as Fe, Ca, Mg and Na, reducing the concentration of Zn (76%), Al (65%), S (46%) and Cu (25%). The kinetic and thermodynamic results of the adsorption of the AM dye with CVDA suggest a fast and spontaneous process, reaching the equilibrium adsorption capacity qeequal to7.57 mg.g-1in 50 min.