Preparation of Magnetic Composite Polyaniline/Fe₃O₄−Hydrotalcite and Performance in Removal of Methyl Orange

Abstract

Magnetic composite fabricated from polyaniline and Fe3O4-hydrotalcite (Pan/MHT) was successfully applicated for removal of methyl orange (MO) from wastewater. The structure and properties of Pan/MHT were characterized by Fourier-transform infrared spectroscopy, scanning electron microscopy, X-ray diffraction, vibrating sample magnetometer, and Brunauer-Emmett-Teller adsorption isotherm. Adsorption kinetic results indicated that the adsorption process followed pseudosecond-order kinetic model ( R 2 = 0.999 ), MO adsorption onto Pan/MHT was well described by Freundlich isotherm ( R 2 = 0.994 ), and the MO adsorption capacity of 2 Pan/MHT obtained the highest with Q e = 156.25 mg / g . Batch adsorption experiments were carried out using magnetic composite with the effects of initial MO concentration, solution pH, and adsorbent dosage. The results revealed that the magnetic Pan/MHT exhibited efficient adsorption of MO in the aqueous solution as a result of the affinity for organic dyes, microporous structure, and suitable surface area for adsorption (15,460 m2/g). The superparamagnetic behavior of Pan/MHT (with H c = 18.56 Oe , M s = 23.38 × 10 − 3 emu / g , and M r = 0.91 × 10 − 3 emu / g ) helps that it could be separated from the solution and performs as an economical and alternative adsorbent to removal and degrade azo dye from wastewater. Pan/MHT was also investigated to reuse after desorption of MO in 0.1 M HCl, and the results show that 2 Pan/MHT can be reused for 4 cycles with Q e = 79.66 mg / g .

Desenvolvimento De Estruturas Hierárquicas Derivadas De Hidróxidos Duplos Lamelares Para Adsorção Do Azul De Metileno

“…Os corantes estão entre os principais agentes poluidores de águas e são empregados em setores industriais como têxtil, cosméticos, couro, fármacos, gráfica etc., com consumo anual de aproximadamente 800 mil toneladas das quais aproximadamente 15% são descartados sem tratamento adequado (Mittal, 2021;Ousafi et al, 2021;Ramos et al, 2021). Diversos métodos físicos, químicos e biológicos vêm sendo empregados e aprimorados para o tratamento de efluentes com corantes orgânicos como filtração por membranas, ozonização, processos oxidativos avançados, coagulação/floculação, degradação enzimática, adsorção , dentre outros (Tran et al, 2021). , A adsorção, por sua vez, tem ganhado popularidade neste cenário devido seu custobenefício, fácil operação, baixa geração de resíduos e possibilidade de reutilização do adsorvente (Uddin et al, 2021).…”