Substance for recovering oil from water, etc. - esp. comprising pretreated cork

A substance for recovering oil and similar cpds. from the surface of water and other substrates is claimed. The substance is cork from the cork oak (Quercus suber) which has been heated under pressure and then comminuted to less than 5mm to give a prod. with an oil sorption capacity of 5-10 times its own lot. Sorbed oil can be recovered from the cork by pressing, centrifuging, solvent extraction and/or distn., or it can be incinerated in situ or after removal from the substrate. The cork may be packaged in an oil-permeable pillow, sock or blanket. It may be used to recover oil from sand and/or shale by intimate mixing and subsequent sepn.