Development of a new styrene copolymer membrane for recycling of polyesterfibre dyeing effluent

A new ultra-filtration membrane has been developed using indigenously avail able polymer, low cost solvents and a simple casting technique. The perform ance evaluation of the developed membrane in terms of pure water permeabili ty (PWP), flux and rejection as compared to commercially available national and international membranes was carried out. It is observed that the newly developed membranes show acceptable performance both in terms of flux and rejection. The compressibility characteristic of the new membrane shows an improvement after suitable chemical modification through cross-linking reac tions, The application perspectives of the membranes developed in our labor atory have been evaluated for the selective separation of dyes from typical textile waste stream of polyester fibre dyeing units with an aim to recove r and recirculate the auxiliary chemicals and water in the process house. T he rejection of dyes >98% and the permeate flux (0.8-1.0 m(3)/m(2) per day) values obtained for a specific type of textile effluent is of acceptable s tandards. The membranes were characterised for pore size and pore size distribution u sing molecular weight cut-off, combined bubble pressure and solvent permeab ility method, Membrane morphology has been studied using scanning electron microscopy (SEM). The other features of the developed membrane are its resi stance to temperature and adverse chemical environment. (C) 2001 Elsevier S cience B.V. All rights reserved.