Download or read book New Thermal Diffusion Techniques Applicable to High-Boiling Petroleum Fractions written by A. Letcher Jones and published by . This book was released on 1958 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thermal diffusion is a means of separating petroleum molecules from each other-in the liquid phase according to their shapes. No change of phase is involved. The principles which govern and limit thermal diffusion separations are completely different from those of distillation, solvent extraction, adsorption, or fractional crystallization (25). As a result of this difference, it is now possible to accomplish separations by means of this newly developed tool that have previously been considered either impossible or so extremely difficult as to be impractical. The advantages of thermal diffusion in extending the ranges of various separation techniques appear to be more pronounced among the higher boiling fractions of petroleum than among the lighter more volatile "front end" constituents. As practically all separation methods are being extended to higher and higher boiling petroleum fractions it is encouraging to realize that we can now extend what appeared to be the practical limits of successful fractionation by combining thermal diffusion with other techniques such as are being discussed at this symposium. It is only within the past ten years that thermal diffusion has been applied to petroleum fractionation (26). Apparatus has been commercially available for less than five years (25). Several dozen different laboratories are now using the principle as a tool of research, but much development remains to be done in apparatus design, operating techniques, and range of application.