Abstract: The invention relates to a process for the purification of a gaseous mixture containing mercaptans and other acid gases comprising a stage of bringing said gaseous mixture into contact with an absorbent solution comprising an alkanolamine, a C2-C4 thioalkanol and water.

Abstract: Composition intended for the flotation of ores, comprising: from 70 to 95% of a combination (A) of n-dodecyl mercaptan (or NDM) and of tert-dodecyl mercaptan (or TDM), the NDM/TDM ratio by weight of which is between 0.5 and 1.5, and from 5 to 30% of a product (B) composed of one or more aromatic or aliphatic compounds comprising from 4 to 100 carbon atoms, preferably from 5 to 40, and having one or two —OH groups. Process for the recovery by flotation of metal compounds of value present in ores employing it.

Abstract: Composition intended for the flotation of ores, comprising: from 70 to 95% of a combination (A) of n-dodecyl mercaptan (or NDM) and of tert-dodecyl mercaptan (or TDM), the NDM/TDM ratio by weight of which is between 0.5 and 1.5, and from 5 to 30% of a product (B) composed of one or more aromatic or aliphatic compounds comprising from 4 to 100 carbon atoms, preferably from 5 to 40, and having one or two —OH groups. Process for the recovery by flotation of metal compounds of value present in ores employing it.

Abstract: A method is provided for zeolite synthesis from a synthesis medium containing in particular a trivalent aluminum source, a tetravalent silicon source, at least an alkaline or alkaline-earth cation in hydroxide form and water in a reactor containing a solid helical moving body in a guiding tube defining an internal space and a space external to the tube. The invention is characterized in that the synthesis medium is circulated in the reactor in a continuous flow passing through the internal space then the space external to the tube and returning to the internal space, only driven by the roation of the solid helical moving body, at a speed of less than 500 rpm, in the tube which is kept fixed, the synthesis medium being kept at a temperature suitable for at least one of the ripening operations or the crystal growth of the synthesized zeolite. The invention also is directed to a device for implementing the method.

Abstract: Process for the synthesis of faujasite, having a Si/Al ratio greater than 1 and which can exceed 3, in the presence of a structuring agent consisting of at least one carbonaceous macrocycle having 10 to 24 atoms per ring and containing heteroatoms chosen from oxygen, nitrogen, sulphur or silicon, the macrocycle being introduced into the reaction medium in the form of a crude synthetic sodium complex.

Abstract: A process is provided for the preparation of zeolites belonging to the faujasite structural class and exhibiting a Si:Al ratio higher than 1 in which a reaction mixture is first produced, which has a pH higher than 10 and contains water, a source of tetravalent silicon, a source of trivalent aluminum, a source of hydroxide ions in the form of a strong inorganic or organic base and a structuring agent ST so as to produce an aluminosilicate gel having the desired composition to permit its crystallization into a compound of the faujasite structural class. The gel obtained is kept at a temperature, pressure and for a sufficient period to effect the crystallization of the gel into a precursor of the zeolite consisting of the zeolite trapping the structuring agent ST in its cavities and the precursor is then subjected to a calcination to destroy the structuring agent and to produce the zeolite.

Abstract: An aluminosilicate gel containing a structuring agent ST and having a composition appropriate for crystallizing as a zeolite of the faujasite structural family is prepared and then subjected to a crystallization to form a zeolite precursor consisting of the said zeolite containing the structuring agent ST in its cavities and channels, and zeolite is produced by calcination of the said precursor. The structuring agent ST consists of at least one compound chosen from the polyalkylene oxides of the formula ##STR1## in which R and R', which are identical or different, each represent H or a C.sub.1 to C.sub.4 alkyl radical, X denotes H or OH, m is equal to 2 or 3 and may be different from one unit to the next and n is a number larger than 12 and preferably between 25 and 800. The zeolites obtained have a Si:Al ratio which is larger than 1 and may exceed 3 and they have a cubic symmetry. These zeolites are usable, directly or after cation exchange, as adsorbents or as catalyst components.

Abstract: A process is provided for dealuminization of zeolites having large pores, the diameter of the aperture of the pores being greater than or equal to about 0.7 nm and the silica/alumina ratio greater than or equal to about 6. The process comprises acid leaching of the raw zeolite containing the structuring agent.The dealuminized zeolites obtained are useful as catalysts for the transformation of hydrocarbons and as selective organophilic adsorbents.

Abstract: The process comprises bringing into contact a naturally alcoholic beer with a hydrophobic zeolite, separating the aqueous eluent phase from the adsorbent, thermally desorbing the adsorbed products, recovering the desorbed phase and separating it by distillation into an alcoholate and an aromatized phase, then reconstituting an alcohol-free beer by mixing the dealcoholized aqueous phase and the aromatized phase with, secondarily, saturation of the reconstituted beer with gaseous carbon dioxide. The reconstituted beer preserves the organoleptic properties of the initial beer.

Abstract: This invention relates to a crystalline synthetic microporous solid containing gallium and phosphorus, whose crystal structure is of the LTA type.After calcination at a temperature above 200.degree. C. the solid obtained can be employed as a catalyst for converting hydrocarbons or as an adsorbent.

Abstract: A process is provided for the preparation of zeolites belonging to the faujasite structural class and exhibiting a Si:Al ratio higher than 1 in which a reaction mixture is first produced which has a pH higher than 10 and contains water, a source of tetravalent silicon, a source of trivalent aluminum, a source of hydroxide ions in the form of a strong inorganic or orgnaic base and a structuring agent ST so as to produce an aluminosilicate gel having the desired composition to permit its crystallization into a compound of the faujasite structural class. The gel obtained is kept at a temperature, pressure and for a sufficient period to effect the crystallization of the gel into a precursor of the zeolite consisting of the zeolite trapping the structuring agent ST in its cavities and the precursor is then subjected to a calcination to destroy the structuring agent and to produce the zeolite.

Abstract: A process is provided for the preparation of a catalyst which is particualrly active and selective in the oxidative conversion of methane into higher hydrocarbons and especially into C.sub.2.sup.+ hydrocarbons.In the process, an aqueous phase containing in solution cations of at least one metal of the lanthanide group and cations of at least one alkaline-earth metal, is brought into contact with a sufficient quantity of a source of carbonate ions or hydroxide ions to form a coprecipitate of carbonates and/or of hydroxycarbonates of the metals, the pH of the resulting reaction medium is brought to a value higher than 8, a coprecipitate is separated from the reaction medium, subjected to a washing operation, then to a drying operation and the washed and dried coprecipitate is subjected to calcination.

Abstract: Production of elementary sulphur from an iron sulphide mineral, which comprises oxidizing acid lixiviation of the pulverized mineral, for extraction of the sulfur. The pulp obtained from the lixiviation is treated in the hot with an organic solvent for sulphur, the solvent having a density higher than 1, to separate this pulp into an aqueous phase containing in solution the non-ferrous metals, the sulphates of which are water soluble, and into a suspension of the solid of the pulp in an organic phase consisting of a solution of sulphur in the solvent separated by decantation and, after separation of the solid in suspension in the organic phase, the sulphur is recovered by crystallization after cooling of the organic phase.

Abstract: Thin layers of polycrystalline silicon are formed atop a metal substrate, by reducing a gaseous silicon containing compound with metallic zinc, in liquid state, and in the presence of at least one other metal which is also in liquid state, same being either tin, lead, gold, silver, antimony and/or bismuth. The reaction is conducted under conditions such that the zinc compound product of reduction is also in gaseous state.