Biocomposite of polyaniline and sodium alginate with Oscillatoria biomass: a potential adsorbent for the removal of basic blue 41

Abstract

Biocomposites of polyaniline (PANI) and sodium alginate (Na-Alg) were prepared with Oscillatoria (OS) biomass and exploited for the uptake of Basic Blue 41 (BB41) dye. The Oscillatoria de-oiled biomass (ODOB) was employed for biocomposites preparation and employed for dye adsorption in batch mode using biocomposites dosage, contact time, pH, initial concentration of the dye and temperature as experimental conditions. The removal capacities of ODOB, Na-Alg-ODOB and PANI-ODOB were found to be 700.1, 634.4 and 786.6 (mg/g), respectively. The functional groups and surface charges were studied by Fourier transform infrared (FT-IR) spectroscopy and pHpzc techniques, respectively. Different models (isotherms, Kinetic and thermodynamic) were performed, the pseudo-second order and Freundlich isotherm models best explained the dye adsorption data onto ODOB, Na-Alg-ODOB and PANI-ODOB. The biocomposites showed higher adsorption efficiency versus other adsorbent under investigation and optimum conditions of contact time, adsorbent dose, pH and temperature were found to be 120 min, 0.05 g, 9 and 303 K, respectively. The BB41 adsorption onto was spontaneous and exothermic process for ODOB, Na-Alg-ODOB and PANI-ODOB. Moreover, the Oscillatoria grown in wastewater and physico-chemical analysis revealed that the chemical oxygen demand (COD), total phosphorous (TP) and total nitrogen (TN) were reduced up to 93.7, 80.8 and 85.5 (%), respectively. The Oscillatoria biocomposites with PANI and Na-Alg could possibly be employed for the treatment of industrial effluents in view of the promising adsorption efficiency.

Keywords

• Adsorption–desorption
• Biocomposite
• Biopolymer
• Oscillatoria biomass
• Basic blue 41
• Kinetics