Abstract: A process and apparatus for subjecting a mixture of two types of electrically charged particles to intense physical contact through a pneumatic transfer modified by turbulent flow and path interruptions to produce surface electrical charges on the particles, and separating the charged particles to recover particles having the same charge. Seeding with a recoverable catalyst may be used as well as forming the path of the mixture from one of the two types of electrically neutral particles. The path interruptions may be sudden directional changes, circuitous paths, baffles, induced vortices and other mechanical apparatus.