چكيده به لاتين
Abstract:
In this project, effect of cold coagulation bath (0°C) and annealing on the performance and structure of cellulose acetate forward osmosis membrane were investigated.Phase inversion method was used for preparation of flat sheet membranes.Various membranes was prepared by different composition of cellulose acetat (CA, Mw=36000 gr/mol) as polymer and 1-methyl-2 pyrrolidone (NMP) as solvent in the casting solutions.The solutions then were immersed into the distilled water bath.Effect of CA concentration and coagulation bath temperature and annealing on morphology,pure water flux, reverse solute flux of the prepared membrane were determined and investigated.Results showed that generally increasing coagulation bath temperature along with decreasing CA concentration, results in increasing the membrane thickness, pure water flux and reverse solute flux.Results also showed that membrane annealing can decreasing pure water flux and reverse solute flux.Also, it was observed that ratios of 20/80 and 17.5/82.5 (w/w) from CA/NMP casting solution and immersion of them into the coagulation bath at 23°C and annealing them after bringing out from bath,resulted in prepration of the membranes which have suitable pure water flux with minimum reverse solute flux,simultaneously.
Keywords: Membrane, Cellulose acetate, Forward osmosis, Phase inversion
