abstract
A previously synthesized PABA-MCM-41 mesoporous material was used to remove Cr(VI) in leather samples. The optimization step was performed using univariate method for the following variables: pH, concentration of Cr(VI) standard, time, dose, and reuse of PABA-MCM-41 adsorbent material. The optimum pH of the adsorption process was equal to 3, the adsorbed amount (q(e)) increased with the increase in initial Cr(VI) concentration, as well as with increase of PABA-MCM-41 dose. The adsorption efficiency increased with the time and the equilibrium was reached in approximately 80 min, with maximum adsorption efficiency of 98.3%. The adsorption kinetic and equilibrium data were better fitted with the non-linear pseudo-first order and Freundlich models, respectively. Leather samples presented Cr(VI) concentration values above of the maximum values regulated by European Union. The PABA-MCM-41 presented Cr(VI) removal percentage values for the real samples between 97.5-99.2%. The PABA-MCM-41 had not matrix effect in the adsorption process, and thus allowing its application in wastewater contaminated with heavy metals. Extraction of the Cr solution and adsorption process of the Cr(VI) by PABA-MCM-41 mesoporous material.
keywords
HEXAVALENT CHROMIUM; LEATHER INDUSTRY; EFFICIENT ADSORPTION; CR VI; MCM-41; PERFORMANCE; SYSTEM; CARBON; ACTIVATION; REDUCTION
subject category
Chemistry; Materials Science
authors
Costa, JAS; Costa, VC; Pereira, ER; Paranhos, CM
Groups