Rhone-Poulenc Industries

Rhone-Progil

Max Michel

Georges Dupuy

Jean-Claude Daumas

Jean-Paul Fort

Laurent Seigneurin

Regis Poisson

Georges Vrisakis

Gilbert Bouge

A crystalline, alkali metal aluminosilicate of type 4A is prepared by reaction between an aqueous solution of an alkali metal silicate and an aqueous solution of an alkali metal aluminate, and includes the steps of (i) introducing a flow of at least a portion of at least one of said reactant solutions into a reaction zone; (ii) co-introducing with said flow (i) an in line flow of at least a portion of the other reactant solution into said reaction zone; (iii) thus establishing in said reaction zone a liquid mixture of said aqueous reactant solutions and said liquid admixture comprising a gel-formation medium; (iv) establishing gel-formation elevated temperatures within said gel-formation medium to effect formation of a mixture comprising an aluminosilicate gel-phase and a mother liquid; (v) recycling said gel-phase/mother liquor to said flow (i); (vi) maintaining said gel-phase comprising said gel-formation medium under such elevated temperatures for such period of time as to effect crystallization of the aluminosilicate, and whereby a suspension of aluminosilicate crystals of type 4A in liquid phase results; and (vii) thence recovering said aluminosilicate crystals from said resulting liquid phase. The resultant aluminosilicate crystals are useful, e.g., detergent additives.

Process for the preparation of crystalline, alkaline, aluminosilicate

The invention concerns catalysts for treating residual gases, containing hydrogen and carbon derivatives of sulphur, by the Claus reaction. These catalysts have a specific area of at least 80 m.sup.2 /g and essentially comprise active alumina and a titanium compound. They enable carbon compounds of sulphur to be destroyed and the Claus reaction proper to be obtained with good yields.

Catalysts for treating gases containing sulphur compounds

The invention is addressed to very light alumina-based agglomerated bodies, the porosity of which comprises pores of large dimensions. These bodies are produced from alumina gels which are dehydrated in hot gas streams so that the amount of water remaining, which can be measured by calcination at high temperature, is from 8 t0 35% of the weight of the treated gels; the treated gels to which other components can be added are agglomerated by any known means. These bodies can be used in particular in adsorption, catalysis, and chromatography.

Alumina-based bodies with large pores, produced by agglomeration

Alumina based bodies having resistance to temperatures of up to 1200.degree. C prepared by autoclaving alumina and at least one additive from the group of oxides of lanthanum, neodymium, praseodymium and thorium. Bodies of the alumina of this invention are useful in adsorption and catalysis.

Alumina-based bodies obtained by agglomeration which are resistant to

Catalysts for Claus reaction treatment of industrial gases containing hydrogen sulphide and sulphur dioxide in which the catalyst has a specific surface area of at least 80 sq.m./g and is composed of activated alumina and a compound of a metal of column III A of the periodic classification of elements which is present, when calculated as the oxide, in an amount within the range of 1-20% by weight of the catalyst.

Process for the treatment of gases containing various derivatives of

Catalysts for Claus reaction treatment of industrial gases containing hydrogen sulphide and sulphur dioxide in which the catalyst has a specific surface area of at least 80 sq.m./g and is composed of activated alumina and a compound of lanthanum, a lanthanide series metal of atomic number 58 to 71 or a metal of Group IIIB of the periodic classification of elements which is present, when calculated as the oxide, in an amount within the range of 1-20% by weight of the catalyst.

Catalysts for the treatment of gases containing various derivatives of

The invention concerns alumina-based spherically shaped grains produced from pastes of moistened particles. These grains are produced by subjecting the pastes, in the form of grains of any shape whatever, to the action of mechanical vibrations of frequencies within the range of from a few herz, in liquids which are slightly or not at all water-miscible. To the alumina, which is the main component, particles of various natures and acids, bases and various compounds which are dissolved in the water used for preparing the pastes, can be added. Once matured, dried and calcined, the grains have a very high level of resistance to attrition, a porosity comprising pores of large dimensions, and can be used in particular for adsorption, chromatography and catalysis.

Agglomerated alumina-based spherical grains

This invention is addressed to a method of catalytic treatment of residual gases containing various compounds of sulphur, particularly hydrolyzable compounds of sulphur by the Claus reaction. These residual gases, at the expense of which all or part of the necessary amount of sulphurous anhydride is formed, are treated at temperatures above 200.degree.C in the presence of catalysts comprising active alumina and one or more oxides, sulphides or compounds capable of being sulphurized, of molybdenum, cobalt, nickel, iron and uranium.

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Yerres, France

Max Michel