Dr. Smitha Rajesh
CEO of Shree Green Consultants & Shree Green Environmental Laboratories, Surat, India & Associated with Department of Chemical Engineering, Sardar Vallabhbhai National Institute of Technology (SVNIT), India
Dr. Smitha Rajesh is a professional working in R&D and Environment field for last 19 years. She has obtained B.Tech. from Govt. Engineering College, Thrissur, Kerala,M.Tech. from Sardar Vallabhbhai National Institute of Technology (SVNIT), Surat,India and PhD from Sardar Vallabhbhai National Institute of Technology (SVNIT), India; all in Chemical Engineering. In addition she has obtained MBA in Operations research as well. She has over 8 years of industrial and over 11 years of research/ Environmental trouble shooting experience. Her research interests are wastewater treatment, Waste treatment schemes, membrane separations, Polymer science, Catalyst science etc She has published 7 full papers in various technical journals and teamed in 4 patents. She has excellent field experience in various waste water technologies and solid/ Hazardous/ Biomedical/plastic waste treatment methods. She is supporting well known industries in India by guiding on environmental rules and regulations and their compliance strategy.

Speech Title: Characterization and method establishment of in situ antioxidant incorporation with polymeric membranes

Abstract: The use of antioxidant as an additive exhibits a direct influence on degradation properties of the polymeric membrane. The other challenges are in generating polymeric membranes from recycled polymers and to extract the virgin monomer from waste material. Aim of this work was to synthesize thermally and mechanically stable ultrafiltration polymeric membranes. Synthesis and characterization of asymmetric ultrafiltration membrane made from polysulfone (PS) with an antioxidant as an additive was carried out. Further, membranes were prepared by phase inversion process from casting solution polymer, solvent, and antioxidant as an additive and a pore former. The MBEP is incorporated through in situ into a polymeric blend membrane of PS and waste polyethylene terephthalate (PET). These membranes are further surface treated. These copolymer membranes are studied in detail. Then polymeric membranes were synthesized from the casting solutions of PS/PET, solvent and antioxidant along with as an additive through in situ process. More membranes were prepared by phase inversion process from casting solution containing PET as polymer, m-cresol as solvent and PEG of different molecular weights as additive. These studies were carried out to evaluate the improvement in anti-fouling properties along with enhancement of thermal and mechanical properties of the membranes. These membranes were characterized in terms of thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), oxidative-induction time (OIT) test, Fourier transform infrared (FTIR) spectroscopy, mechanical measurements and cross-flow filtration for milk concentration, pure water permeability (PWP), molecular weight cut-off (MWCO), flux and membrane morphology and scanning electron microscopy (SEM). The presence of additive also affects the surface roughness, membrane morphology and mechanical strength. From experiments it is also observed that when the antioxidant quantity increases the morphologies and properties of resultant membranes become excellent. The surface wettability of blend polymeric membranes with antioxidants was significantly improved. Further, flux studies and fouling experiments were carried out with effluent from textile industry. The stability of modified membranes was evaluated by immersion tests. The effluent was used as a model foulant to investigate the anti-biofouling performance of modified membranes. The results of stability tests showed that modified membranes had better mechanical and chemical stability.