Prodn. of paraffin oils - comprises extracting solvent raffinate with super-critical gases using carbon di:oxide, propane and butane

摘要

Prodn. of paraffin oils comprises extracting a solvent raffinate with supercritical gases, pref. in two steps. Pref. in the first step 20-100 wt% CO2, 0-80 wt% propane and 0-80 wt% butane is used as the extractant, and in the second step, the gas mixt. is the same or opt. contains up to 15 wt% ethanol; the temp. is 50-150 deg.C and the pressure is 2-4x10 power7 Pa. USE/ADVANTAGE - For producing paraffin oils as a base for pharmaceuticals and cosmetics. Avoids the problems of obtg. the prod. by distn. when it can be contaminated with aromatic cpds. which require a hydrogenation step for their removal