Supercritical fluid extraction of Brazilian coal with alcohols

This article describes the extraction of coal raw material with an homologo us series of low molecular mass alcohols in the supercritical state. The ex traction system used was projected and built in the Institute of Chemistry of Sao Carlos. Because the system has low cost and is easy to handle, it pr esented very good results. The extraction yields obtained with the alcohols ranged from 32 to 46%, the highest yield was obtained with ethanol. Supercritical fluid extraction sh owed to be an efficient extraction technique, and the use of ethanol has se veral advantages since it is a relatively low toxicity solvent, of low cost , and abundant in Brazil. Chromatographic and spectroscopic techniques were used to characterize the extracted materials.