Abstract: The process described herein presents a unique method of separating and converting polymers and hydrocarbon composites to light/medium weight hydrocarbons from polymer and hydrocarbon composites waste. The method involves the removal of moisture from the hydrocarbon composite and/or polymer waste followed by or in conjunction with a catalytic reaction which takes place at slight negative pressure in anaerobic conditions. The light/medium weight hydrocarbons are then recovered in the vapor phase. The vapors are condensed and separated by conventional techniques. Residual solids, substantially free of hydrocarbons and polymers may be furthered processed and recycled by conventional means. The conversion process has also been applied to natural occurring heavy and low grade hydrocarbon deposits such as oil and tar sands.