Abstract: A method is provided for cleaning parts soiled with oil components and seating terpenes from oil compositions using filters having suitable pore sizes to allow terpene components to pass through the walls of the filter as a permeate while not allowing oil components to pass therethrough. A separate aspect of the present invention utilizes a ceramic filter capable of separating water components from a mixture of terpenes and oil, thus allowing filtered water to be reused in a cleaning procedure. Using both types of filters in one operation provides a substantially closed loop recycling system where terpene components can be reused to clean additional articles, water can be reused to rinse such articles and contaminants removed in the cleaning process can be either reused or disposed of.

Abstract: Disclosed is a process for separating components of liquids in industrial processes for cleaning of articles. The process is directed toward a terpene-based cleaning system including washing and rinsing of contaminated articles and which further includes separating components of used wash and/or rinse solutions into component parts so that terpene components of the solutions can be recycled for further washing and the water component of the solutions can be purified and recycled for rinsing. The method can include filtering a stream directly from the wash solution to avoid fouling of the filter. The method also includes using a cross flow filter having a pore size of between about 50 .ANG. and about 7,500 .ANG. to effectively separate water from remaining components of the contaminated wash solution.