In situ synthesis of Nanoparticle-embedded polymer: polyaniline-magnetic graphene oxide nanostructure for removal of fatty acids from dairy effluents

Abstract

Dairy effluents can be considered as the most polluting wastewater from food processing due to the high pollution-loading and the presence of large amounts of organic compounds such as casein, carbohydrates and fatty acids. Dairy effluents containing fatty acids have adverse effects on the environment and human health due to their stability and biodegradation.Therefore, in the present study, an adsorbent based on polyaniline-magnetic graphene oxide nanocomposite (MGO @ PANI) was synthesized through in situ polymerization of aniline monomer to remove fatty acids in industrial effluents. In situ synthesis is designed to overcome the challenge of nanoparticle aggregation where polymers typically act as nanoreactors and serve as an environment for nanoparticle synthesis. The presence of oxygenated functional groups such as hydroxyl and epoxy groups in graphene oxide (GO) and the presence of nitrogen-containing functional groups such as imine and amine groups in polyaniline all contribute to the absorption of fatty acids. characterization of functional groups, morphology and composition of adsorbent element of MGO @ PANI were performed by FT-IR, FE-SEM and EDX techniques. the parameters affecting the efficiency of fatty acid removal such as pH, adsorbent dose, contact time, concentration and temperature were investigated. The results showed that MGO @ PANI showed high efficiency by removing 94.60% of fatty acids (under optimal conditions of pH 7, dose 15 mg, time 50 minutes at room temperature). The experimental data were well matched with the Freundlich adsorption isotherm (multilayer model of the adsorption process). The study of adsorption kinetics also reveals semi-second-order kinetics. In addition, the thermodynamic study showed that the adsorption of fatty acids on MGO @ PANI is exothermic and the mechanism of physical adsorption.

Keywords

• in site polymer synthesis
• fatty acid removal
• dairy industrial effluent
• polyaniline conductive polymer