سال انتشار: ۱۳۹۰
محل انتشار: کنفرانس بین المللی فرآورش پلیمرها
تعداد صفحات: ۴
Mohammad Izadyar – Department of Chemical Engineering, Faculty of Engineering, University of Isfahan
Amir H. Navarchian – Department of Chemical Engineering, Faculty of Engineering, University of Isfahan
Morteza Sadeghi – Department of Chemical Engineering, Isfahan University of Technology, Isfahan, Iran.
The membrane gas separation is a very safe, low cost and efficient approach for separation of many petrochemical gasses. Polyaniline (PANi) is a conducting polymer and the dense membranes made from this polymer have excellent selectivity for binary gas mixtures such as O2/N2 and CO2/CH4 . The molecular spacing and free volumes of polyaniline chains can be controlled by its interesting doping/undoping chemistry . The sufficient difference between molecular sizes of these gases allow desired selectivity in gas separation (CO2 (3.23Å), O2 (2.92 Å), N2 (3.64 Å), and CH4 (3.8 Å)) .In this research, PANi was first synthesized from aniline in presence of HCl and ammonium peroxodisulfate (APS) according to MacDiarmid approach . The undoping process was carried out using NH4OH solution 1M. The PANi films were then prepared by casting solution method using N-methylpyrrolidinone (NMP) as solvent. The structure of synthesized polyaniline has been characterized by Fourier Transform Infrared Spectroscopy (FTIR). The molecular weight of synthesized polymer has been determined (117767g/mol) by Cannon-Fenske viscometer using Mark-Houwink-Sakurada equation.The permeability of prepared as-cast and undoped membranes at 80°C, have been successfully determined for CO2 (1.39 and1.56), O2 (0.4 and 0.47), N2 (0.056 and 0.05), and CH4 (0.04 and 0.034). The selectivities of O2/N2 and CO2/CH4 gas pairs were 7.14 and 34.75, respectively for as-cast film; and 9.4 and 45.88, respectively for undoped film. This means that undoping process can enhance the selectivity of PANi membrane significantly.