Abstract: A water dealkylation catalyst of aromatic hydrocarbons containing at least one metal of Group VIII and eventually, one metal of group VII.sub.b deposited on a gamma alumina of special properties containing at least 1000 ppm of sulfate ions having undergone a pre-treatment in aqueous medium at a pH between 1 and 10 at a temperature below 100.degree. C. The catalysts contain rhodium on pre-treated gamma alumina and the bimetallic catalysts contain 2 metals of the group VIII or one metal of the group VII and one metal of the group VII.sub.b on pre-treated gamma alumina.

Abstract: Heavy fuel-oil composition of improved stability under storage conditions, comprising a petroleum residue obtained from a straight run distillation, a vacuum distillation or a viscosity reduction of petroleum materials, a diluent such as a steam-cracking residue, a viscosity reduction gas oil or a mixture thereof, and a minor proportion of a sequenced copolymer formed of two polymeric sequences (A) and (B) wherein sequence (A) is obtained by polymerization of one or more conjugated diolefins such as 1,3-butadiene and isoprene and sequence (B) is obtained by polymerization of acrylonitrile or an alkylacrylonitrile such as methacrylonitrile, said sequenced copolymer having an average molecular weight by number of from 1,000 to 20,000.

Abstract: A process for improving the properties of a bitumen which comprises mixing the bitumen with from about 5 to 20% by weight based on the bitumen, of a polyolefin wax at an elevated temperature for a period of time necessary to form a homogeneous mixture. The modified bitumen is particularly useful as a binder in asphalt to be used for casting.

Abstract: This invention relates to a new process for the preparation of improved polymeric bitumens.The process is characterized by preparing a first composition by admixing a petroleum fraction (160.degree.-230.degree. C.), while stirring, at a temperature of from 80.degree. C. to 120.degree. C., with a copolymer made of styrenic blocks and dienic blocks such as a styrenebutadiene disequenced or multisequenced or statistical copolymer having a molecular weight varying between 30,000 and 300,000 and crystallized sulfur which is not chemically bound.When homogeneity is obtained, a portion of said first composition is admixed for at least 15 minutes at a temperature of from 130.degree. C. to 230.degree. C., with a conventional bitumen (penetration 20-220) to form a fluid polymeric bitumen.The fluid polymeric bitumen obtained by the process of the present invention is an excellent product characterized by superior properties and this product can be used in conventional spreading means when applying coatings onto roads.

Abstract: An apparatus to measure the asphaltene content of petroleum products where a precipitation evaporator for the sample is surmounted by a condensing unit. Immediately below the precipitation evaporator is a filtering unit with a rinsing vapor inlet line for conveying washing liquid from a balloon-flask evaporator. The precipitation evaporator is also equipped with an adjustable flap for preventing fluid from passing to the filtering unit.

Abstract: Catalyst for water dealkylation of oil fractions containing monoalkylated or polyalkylated aromatic hydrocarbons, said catalyst containing at least one metal of group VIII in a proportion of 0.1 to 5% by weight on a carrier, characterized in that said carrier is a zeolite L that can be exchanged with either alkaline cations or polyvalent cations of groups V.sub.b, VI.sub.b and VII.sub.b. The zeolite L can be exchanged with a solution of metals such as lithium, sodium, caesium, chromium, manganese, and rhodium. A method of using the catalyst by contacting the hydrocarbons with the catalyst at a temperature of 400.degree.-600.degree. C., a pressure of 0-80 bars, a space velocity of the hydrocarbon of from 0.1 to 10h.sup.-1, and a water to hydrocarbon mol ratio of 2-20.

Abstract: A process for the preparation of bitumen-polymer compositions, characterized by the fact that the bitumens are modified by grafting of a dihalopolybutadiene polymer that serves as a receptive structure to block polymers and to elastomers co-vulcanizable with the grafted bitumen.The elastomers are selected from the group that includes linear polybutadiene-polystyrene block copolymers, a polystyrene-polybutadiene block copolymer, and a vulcanizable polynorbornene rubber. They are used as road and industrial bitumens.

Abstract: Water dealkylation catalysts of petroleum fractions containing monoalkylated or polyalkylated aromatic hydrocarbons including at least one metal of group VIII deposited in a proportion of from 0.1 to 5% by weight on a spinel, and having deposited in a proportion of from 0.1 to 5% by weight on a spinel, and having improved properties of activity, selectivity and stability, characterized in that the carrier is a mixed spinel of the formula (M.sub.x M'.sub.1-x)Al.sub.2 O.sub.4 wherein M is a bivalent base metal of group VIII such as nickel, iron and cobalt and M' is a bivalent metal belonging to groups 2a, 7b, 1b or 2b such as magnesium, manganese, copper and zinc.The mol. ratio M/M' may vary from 0.5:1 to 50:1, preferably from 1:1 to 20:1.

Abstract: A process for storing heat in the form of fusion/solidification latent heat which comprises passing a thermo-conductive fluid into a thermally insulated storage element containing a substance having a melting point that corresponds to the supply and heat consumption temperatures, characterized in that said fusible substance is absorbed on a microporous carrier which forms a granular bed in which the thermo-conductive fluid circulates.

Abstract: The invention relates to the catalytic treatment of a gas oil feed stock, distilling between 150.degree. and 530.degree. C., in a reactor zone whose temperature is comprised between 200.degree. and 500.degree. C., the pressure is comprised between 15 and 80 bars and containing a hydrogen form zeolite as catalyst, in the presence of a quantity of isobutane representing from 5 to 100% of said feed stock.The process is particularly suitable for the improvement of the filtration temperature limit of the gas oils.

Abstract: The invention is directed to a catalytic process for hydro-treating gas oils in order to improve their flow properties, the feed stock being treated at a temperature of between 400.degree. and 550.degree. C., under a total pressure of between 18 and 60 bars with a hydrogen/hydrocarbon molar ratio of between 2 and 8 in the presence of a catalyst comprising by weight from 0.1 to 1% of platinum and 0.01 to 1% of iridium deposited on an alumina support having a specific surface higher than 50 m.sup.2 /g, a silica content of less than 10% weight and a halogen content of less than 0.1%.

Abstract: A roof structure has a supporting base on which a layer of insulating material is placed and over which is a metal layer having water circulating channels. The metal layer is covered by a water proofing layer, the outer surface of which is covered with mineral particles. The roof structure serves both the function of a conventional roof and a solar energy collector.

Abstract: Process for obtaining alkyl- and arylalkylthiosulfates in a water-organic solvent two-phase system by nucleophilic substitution of the halogen of an alkyl or arylalkyl halide by a thiosulfate ion, characterized by the fact that the substitution is effected in the presence of a phase transfer agent acting as a catalyst and used in catalytic proportions.

Abstract: Apparatus permitting an improvement of the carburetion of internal combustion engines fitted downstream of a multibody carburetor and upstream of the induction manifold.The primary homogenization chamber forming an extension of the primary body issues tangentially via an orifice into the top of the secondary homogenization chamber, namely into an annular space defined by the walls of the secondary chamber and the secondary mixture supply pipe. The secondary chamber is equipped in such a way as to form a homogenizer and to this end has fixed vanes.Application to automobiles.

Abstract: The instrument comprises a viscometer for a product such as bitumen and a pump for transferring the product to a flat wall-type heat exchanger. A channel formed in the heat exchanger wall is brought to an adjustable temperature and the channel output is connected to the viscometer. A probe for measuring the temperature of the product is placed within the viscometer, the temperature being adjusted to an index value within a predetermined range by means of a regulator for varying the pump output and controlling the temperature of the heat-exchanger wall.

Abstract: The invention is related to new bitumen compositions having improved rheological properties.The compositions are characterized in that they contain:90 to 99.9% in weight of a bitumen, its softening point being comprised between 20.degree. and 120.degree. C.,0.1 to 10% in weight of a norbornene polymer, its average molecular weight being between 1,000,000 and 3,000,000.The compositions of the invention are used particularly as superficial coats in road surfacing.

Abstract: A method of preparing novel bitumen compositions which comprises a first step wherein an olefinic unsaturated organic compound having a molecular weight varying between 300 and 30,000 is added to a bitumen having a penetration value varying between 30 and 220, and a second step wherein a polymer having a molecular weight varying between 100,000 and 2,000,000 is added to the product obtained from said first step.

Abstract: The present invention is related to a novel process for preparing bitumen-polymer compositions. These compositions contain block copolymers comprising diene and styrene groups.The compositions present excellent mechanical properties even at low temperatures.

Abstract: This invention relates to a method of dehydrocyclizing aliphatic hydrocarbons to form corresponding aromatic hydrocarbons. According to the invention, a batch of aliphatic hydrocarbons, in the presence of hydrogen at a temperature of 430.degree. to 550.degree. C is passed over a catalyst consisting essentially of a type L zeolite having exchangeable cations of which at least 90% are alkali metal ions selected from the group consisting of ions of sodium, lithium, potassium, rubidium and caesium and containing at least one metal selected from the group which consists of metals of groups VIII of the periodic table of elements, tin and germanium, said metal or metals including at least one metal from group VIII of said periodic table having a dehydrogenating effect, so as to convert at least part of the batch into aromatic hydrocarbons. The aliphatic hydrocarbons preferably contain 6 - 10 carbon atoms.

Abstract: The enclosure comprises an insulating and demountable sealed box unit fitted with a closure lid and placed around a chromatographic column consisting of a metal tube of constant cross-section, said tube being arranged in the form of a helix and supplied with electric heating current which is cut-off for cooling purposes. The heating and cooling air is supplied through a coaxial injection pipe and nozzle, circulated axially through and then around the column within the box unit, then discharged through the bottom wall of a collector casing.