Reverse osmosis separations of some organic and inorganic solutes in aqueous solutions using aromatic polyamide membranes

摘要: The reverse osmosis separations of some ethers, ketones, aldehydes, monocarboxylic acids, and inorganic salts in single-solute (55–454 ppm) aqueous solution systems using aromatic polyamide membranes have been studied at 250 psig. It was found that separation essentially a function steric parameter for both polar parameters alcohols. Solute acids passed through minimum pKa value ∼4.8. values the free-energy Li+, Na+, K+, Rb+, Cs+, F−, Cl−, Br−, I−, IO3− ions calculated used. above cations are negative those anions positive, suggesting membrane surface behaves as if it is positively charged. Further, data show material only about 40% cellulose acetate earlier.