Abstract: The invention relates to a process for the sweetening of a petroleum fraction in a fixed catalytic bed in the presence of an oxidizing agent, by catalytic oxidation of the mercaptans which it contains, in the presence of a catalyst in the form of a support impregnated with a metal chelate and in the absence of an aqueous base, the water content of the support is maintained within a predetermined range of values by action on the solvent power of the feedstock for the water of the support as a function of temperature.

Abstract: The invention relates to a method for the continuous cleaning of the inside of a tube in which a fluid circulates, in which method there is continuously driven in rotation within the tube by the fluid a movable element, one end of which is fastened to one end of the tube through a mechanical linkage permitting it to rotate freely on itself about the axis of the tube. In accordance with the invention, the movable element comprises at least one sharp edge designed to scrape the inner surface of the tube, this edge being disposed so that during the rotation of the movable element it is, along every cross section of the tube, the portion of the movable element farthest removed from the axis of the tube.

Abstract: A process for improving the deasphalting of a heavy hydrocarbon feedstock with a solvent by subjecting the feedstock to shearing alternatively after and/or before the addition of at least a portion of the solvent to the feedstock is disclosed. Alternative means for effecting the shearing and desired ranges of shear are also disclosed.