Method for removing oil or asphalt from inorganic particles having

Abstract

A method for deoiling oil residues from surfaces of inorganic particles each having pigment in an outer layer thereon, comprising contacting the surfaces with a deoiling solution comprising a mixture of monocyclic terpene and aliphatic petroleum distillates in an amount and manner effective to wet substantially all the surfaces of the inorganic particles, whereby the deoiling solution removes substantially all the oil residues from the surfaces of the inorganic particles. In a preferred embodiment, there is a method for deoiling oil residues from surfaces of inorganic particles each having pigment in an outer layer thereon including introducing the inorganic particles into a structure having a wall portion which defines a receptacle having upper and lower openings, the structure including a porous support member having a pore size which permits the passage of liquid but not the inorganic particles located in the receptacle between the first opening and the second opening to define a particle holding chamber, and, then, deoiling the inorganic particles by introducing into the upper opening a deoiling solution comprising a mixture of monocyclic terpene and aliphatic petroleum distillates, and, then, rinsing the deoiled inorganic particles with water and drying the rinsed inorganic particles, in that order.