Abstract: An apparatus for the catalytic cracking of hydrocarbon feedstocks with reaction temperature control is provided which includes an upward-flow or downward-flow cracking column, means for feeding said column under pressure with a hydrocarbon feedstock and with particles of a regenerated cracking catalyst, at least one means for injection of an auxiliary fluid downstream of the zone in said column where the hydrocarbon feedstock and the regenerated catalyst particles are contacted with each other, to reduce the temperature of the reaction zone situated directly downstream thereof, means for separating the products of the cracked feedstock and the spent catalyst particles, at least one stripping means, at least one unit for regeneration of the catalyst by combustion of the coke deposited thereon and means for recycling the regenerated catalyst to said feeding means.

Abstract: A process for deasphalting a heavy hydrocarbon feedstock, comprising two stages of precipitation from the feedstock of an asphaltene fraction alone or, alternatively, of a resin fraction along with the asphaltene fraction, by means of a heavy solvent and a light solvent, respectively, is disclosed.In accordance with the process, the heavy solvent and the light solvent both contain, in different proportions, at least one hydrocarbon having 3 carbon atoms and at least one hydrocarbon having at least 5 carbon atoms, the proportion of the hydrocarbon having 3 carbon atoms being higher in the light solvent than in the heavy solvent.

Abstract: EPDM and/or EPR rubber/silicone compositions having improved thermal properties, well adapted for the production of a wide variety of useful shaped articles, e.g., automotive seals, gaskets and belts, include a 2-mercapto-benzimidazole or salt thereof, preferably the zinc salt, an antioxidant comprising a secondary amine function, a diorganopolysiloxane oil, appropriate filler material and a peroxide crosslinking catalyst.

Abstract: The invention relates to the continuous or discontinuous analysis of the corrosive effect of the soil and the environment on a buried metallic structure (such as an underground gasoline storage tank for retail gas stations). The apparatus includes a measuring system having a sensor with at least one Cu/CuSO.sub.4 electrode to which a metallic electrode containing iron is secured at least one voltmeter, and optionally at least one current generator; at least one data display and acquisition system consisting of at least one amplifier, at least one analog-to-digital converter, at least one magnetic recorder and at least one display unit for the read-out of these data on the site, these belonging to the group formed by the numerical display devices and the electromechanical recorders; and a system for the processing of these data consisting of data-processing computing means.

Abstract: Composite catalytic products composed of a metal chelate based catalyst on a solid adsorbent support for use in fixed-bed processes for sweetening mercaptans contained in petroleum fractions are disclosed. The composites contain from 0.05 to 5 weight percent of a metal chelate, from 5 to 15 weight percent of pyrolyzed carbon and from 60 to 90 weight percent of a mineral matrix. The support material is obtained by pyrolysis of wash concentrates of raw wools.

Abstract: The invention concerns a positioning device for a tube cleaning element rotatably driven by fluid passing through the tube. This is particularly useful for heat exchanger tubes. This device includes an open-frame support member (1) having one or more parts (8a, 8b) (preferably of generally cylindrical shape) for mounting on the outside on one end of said tube, and further includes a spindle (2) mounted for rotation with respect to said frame (1) along the axis of the end of said tube and adapted to be fastened to said rotatable element.

Abstract: A method and apparatus for determining the thawing point of jet fuels by first cooling a sample of the fuel until crystals appear and then heating the sample until the crystals disappear, detecting the point at which the crystals appear both thermally and optically, detecting the point at which the crystals disappear both thermally and optically and correlating the resulting measurements to obtain an indication of the thawing point.