Abstract:
This project is to study the preparation of celluloseacetate for reverse osmosis. Acetone and magnesiun perchlorate havebeen used as solvent and swelling agent, respectively. Proportionof magnesium perchlorate to polymer solution have been varied as0.0, 0.5, 1.0, 1.5, 2.0, 2.5 and 3.0 percent by weight, while othercomponents were kept constant. Proportion of cellulose acetate topolymer solution in 13.2, 15.0 and 18.0 percent by weignt have alsobeen investigated. Separation of phenol solution were carried out inthe wide pH range, starting from pH 6, 7, 8, 9, 10, 11 and 12,respectively.It was found that the polymer solution contains 1.0 percentby weight of magnesium perchlorate gave the maximum flux at 56.10liter per squaremetre-hour. Flux is increase with decreasingproportion of cellulose acetate in the polymer solution.At pH6 and7, percent reject ion of the phenol solutionhave the negative values. This is due to the membrane has slightlynagative charge and can act as a proton acceptor. Thereface, phenolis preferentially adsorbed on the membrane surface. At PH 11 and 12,the structure of cellulose acetate would be destroyed by hydrolysisgiving cellulose and acetic acid. This causes the fluctuation of theflux. At pH 9 and 10, sepatation of phenol solution are as hight as88.03 and 66.68 percent, respectively, and the flux is smooththrouyhout the experiment.Investigation of the structure of membrane was carried outby Scanning Electron Microscopes. The results show that thestructure is asymmetry. Thickness of the membranes are approximatelyin the ranges 90-120 micrometres. Thickness of skin layery areapproximately 5-10 micrometres and the support layer thickness arein the ranges of 95-100 micrometres.