Reverse osmosis separation of several organic solutes from aqueous solutions-monocarboxylic acids, esters, aldehydes, ketones and alcohols were investigated using cellulose acetate butyrate membranes. Separation was not so good as reported by Manjikian and virtually same as with cellulose acetate membranes. Matsuura's correlation is applicable to cellulose acetate butyrate membrane separation except high Taft's number.
