Abstract: An apparatus and method are disclosed for preferentially separating a high vapor pressure component from a low vapor pressure component, wherein at least a portion of each component is volatilized from a matrix. A matrix, such as a sludge contaminated with volatilizable organic materials, is directed through a housing by a screw conveyor. Heat is applied to the matrix in an amount sufficient to volatilize at least a portion of the high and low vapor pressure components. A portion of a high vapor pressure component volatilizes at an inlet end of the housing while a portion of a low vapor pressure component volatilizes at an outlet end of the housing. The volatilized components are then preferentially separated by a hot gas, which is discharged over the matrix from a gas inlet tube, through separate outlet ports. The volatilizable components of the matrix are thereby preferentially separated.