Estudo do Hidroxinitrato de Zinco como adsorvente para o corante Alaranjado de Metila e aplicação dos resíduos sólidos como agente de reforço em (nano)compósito

Abstract

In this study, a layered hydroxide salt, specifically zinc hydroxide nitrate, Was synthesized by the co-precipitation method and was used as an adsorbent for the removal of orange dye from methyl (AM) by the adsorption technique in aqueous solutions, which consisted of concentrations of 100 to 100 mg.L-1 in 10 Points of a mechanical stirrer, aliquots being withdrawn at predetermined times. was used as adsorbent for removal of methyl orange dye (MO) from aqueous solutions. The effects of initial dye concentration, contact time and temperature were investigated. Adsorption isotherms were analyzed from Langmuir and Freundlich equations, and the data were best fitted to the Langmuir model. Thermodynamic parameters of adsorption were determined and showed that the process is non-spontaneous and exothermic. Adsorption kinetics was studied by applying the pseudo-first and pseudo-second order kinetic models, and the experimental data were fitted better to the pseudo-second order model the activation energy indicating a process of chemical nature. The solid residues obtained were applied as nanofiller in polymer (carboxymethylcellulose - CMC), the amount of filler percentage of 0.5, 1.0, 2.0 and 4.0 wt% in relation to the CMC. The mechanical properties were studied by the tensile test, which provided data on the Young’s modulus and maximum, indicating that the nanocomposite the value of some samples were improved. The adsorbent and obtained (nano)composite was characterized by scanning electron microscopy (SEM) coupled with energy dispersive X ray (EDS) and x-ray diffraction (DRX), Visible Spectroscopy (UV-VIS) and mechanical properties were studied by mechanical tensile tests.