Baker’s yeast-MnO2 composites as biosorbent for Malachite green: An ecofriendly approach for dye removal from aqueous solution

• Published in: Revista ambiente & água Vol. 14; no. 1; pp. 1 - 15
• Main Authors: Santos, Bruna Assis Paim dos, Cossolin, Aline Silva, Reis, Hélen Cristina Oliveira dos, Castro, Ketinny Camargo de, Silva, Evanleide Rodrigues da, Pereira, Gabriele De Menezes, Sousa Junior, Paulo Teixeira de, Dall'Oglio, Evandro Luiz, Vasconcelos, Leonardo Gomes de, Morais, Eduardo Beraldo de
• Format: Journal Article
• Language: English
• Published: Taubaté Instituto de Pesquisas Ambientais em Bacias Hidrográficas 2019; Instituto de Pesquisas Ambientais em Bacias Hidrográficas (IPABHi)
• Subjects: Acidic oxides; Adsorption; Analytical methods; Aqueous solutions; Biosorption; Color removal; Composite materials; Data processing; Dosage; Dyes; ENGINEERING, ENVIRONMENTAL; Fourier transforms; Infrared spectroscopy; isotherm and kinetic models; Malachite green; Manganese dioxide; Oxidation; Particulate composites; pH effects; Potassium permanganate; Removal; thermodynamic model; Yeast; Yeasts; modelo termodinâmico; thermodynamic model; biosorption; biossorção; isotherm and kinetic models; modelos isotérmicos e cinéticos
• DOI: 10.4136/ambi-agua.2254
• EISSN: 1980-993X

In this study, baker’s yeast-MnO2 composites, produced by direct oxidation of yeast with KMnO4 under acidic conditions, were used as biosorbent to remove the triphenylmethane dye Malachite green (MG) from an aqueous solution. Parameters that influence the adsorption process, such as pH, contact time, temperature, initial dye concentration and biosorbent dosage, were evaluated in batch experiments. The optimum removal of MG was found to be  86.7 mg g-1 at pH 10, 1.0 g L-1 of biomass dosage and 45°C. The kinetic data of dye removal was better described by the pseudo-second-order model. The adsorption process followed the Langmuir isotherm model and the maximum biosorption capacity was estimated to be  243.9 mg g-1 (at 25°C). The negative values of ∆G° and the positive value of ∆H° indicated that the MG biosorption onto yeast-MnO2 composites is spontaneous and endothermic. Fourier transform infrared spectroscopy (FTIR) indicated that the nano-MnO2 particles deposited on yeast-MnO2 composites surface facilitated the MG adsorption. It was concluded that baker’s yeast-MnO2 composites have potential for application as adsorbent for removal of MG from aqueous solution.