I joined this site because of this question.
There has been very little research done on the use of frequency as an energy source and/or method of replacing heat in separation/purification methods within industry. Every molecule has a natural frequency that can be used to combine or separate them from elements. Thus, this can either release the energy that created (thing of separating hydrogen from oxygen in water) them or allow purification separation of sand/clay and bitumen. The latter apparatus already exists and can be seen here: http://www.freepatentsonline.com/7867384.html
Unfortunately, heat is always been the method of separation/purification and few others have been significantly studied.