Synthesis of New Macromolecular Ionic Liquids for Environmental Remediation

Abstract

Present research work is divided into two parts (1) This part is based on synthesis of new macromolecular ionic liquids and membranes using cellulose acetate for environmental remediation. The synthesized materials are characterized using FTIR, H-NMR, SEM, XRD, BET and TGA respectively while the electrochemical properties are measured using impedance spectroscopy and an equivalent circuit model for all fabricated membranes is also designed for future applications. For environmental remediation, a toxic and carcinogenic insecticide “Pirimicarb” is chosen and an extensive study on adsorption process by varying parameters (time, concentration, temperature) is carried out. Different kinetics (first order, pseudo second order) and Isotherm models (Langmuir, Freundlich, Temkin, Intraparticle diffusion model) are also applied and fitted on the experimental data and the output results are discussed in details. Results revealed that fabrication of ionic liquids into membranes has enhanced their adsorption capability and % Removal by most of the membranes is above 70%. The optimum %Removal concentration observed is 5mg/L while the temperature between 50º to 75 º C is proven best for adsorption process. Thermodynamic studies have proven spontaneous, endothermic and entropy driven reaction mechanisms. (2) Second part of research work is based on use of commercial ionic liquids [C2mim][OAc- ] and [C2im][NTf2] for chitin loaded IL films preparation. Chitin is extracted from shrimp shells after microwave treatment. Chitin-IL films (1.5 wt %) are prepared using two approaches (1) loading method (2) co-dissolution method. Prepared chitin-IL films are then successfully characterized using FTIR, TGA and UV-Vis spectroscopy. The prepared films subjected to cyclic voltametric study using Potentiostat. Results revealed that chitin films (insulator) are successfully converted into conductive films by the introduction of IL in them and conductivity values recorded within 193-222 µS/cm. The present research work helps us to investigate and study a much broader horizon and greener aspect of ionic liquids which was rarely discussed by scientists so far. Synthesized ionic liquids can not only used as efficient adsorbents but can also use for making conductive films for super-capacitor industry and energy storage device sapplications