Reverse osmosis with dynamically formed membranes from water‐soluble polymers

Abstract

SynopsisMembranes were dynamically formed from poly(acry1ic acid), poly( 1-methyl-2-vinylpyridinium iodide), and methylcellulose on a Millipore filter. The effects of the conditions of membrane formation on reverse osmosis performances and the membrane structure were investigated. The primary factors that affect membrane performance were ascertained to be the kind and concentration of salts and the pH of the preparing solutions, the concentration and the polymerization degree of the membrane materials, the pore size of filters, and the pressure and circulation velocity during membrane formation. Two types of dynamically formed membranes, the membranes inside the filter and the membranes on the filter, were distinguished.

Review of Dynamic Membranes

“…The methylcellulose-modified membrane rejected 72% of the NaCl with a permeability of 0.22 L/m 2 .h.bar. Igawa et al (1978) also investigated the influence of the addition of the PAA. Like Thomas (1977), they report that the highest NaCl rejection rate was achieved when the PAA was introduced at pH 2, and the pH then gradually increased to a pH level of 7.…”