Rhone-poulenc Industries

Gilbert Bouge

Laurent Seigneurin

Thierry Dupin

Regis Poisson

Roland Jacques

Max Michel

Georges Vrisakis

Shaped titanium oxide catalysts/carriers useful, e.g., for sulfur recovery via Claus catalysis, are prepared by (i) intimately admixing powdered, poorly crystalline and/or amorphous titanium oxide, said titanium oxide powder being characterized by a weight loss on ignition ranging from 1 to 50%, water and from 0 to about 15% by weight of a shaping additive, (ii) next shaping the intimate admixture which results, and (iii) thence, optionally after drying, calcining the product shaped article.

Preparation of shaped titanium dioxide catalyst/carrier and catalysis of

Aqueous suspensions of alumina particulates, at least a portion of which comprising ultrafine boehmite, are prepared by maintaining a pH&lt;9 aqueous formulation of poorly crystallized and/or amorphous activated alumina powder for such period of time as to effect the at least partial transformation of such alumina powder into ultrafine boehmite.

Process for preparing alumina particulates, at least a fraction of which

Spheroidal alumina particulates having bifold porosity are prepared by (i) intimately admixing, at a pH of less than about 7.5, (a) a sol of a member selected from the group consisting of ultrafine boehmite and pseudo-boehmite, said sol being devoid of amorphous alumina and the concentration by weight thereof, in content by weight of Al.sub.2 O.sub.3, being between 5 and 25%, with (b) from 30 to 95% by weight, based upon the total solids content of the admixture, of spheroidal alumina particulates essentially completely in at least one of the phases eta, gamma, delta and theta, such particulates having a micropore volume ranging from about 0.4 to 1 cm.sup.3 /g, a specific surface ranging from about 100 to 350 m.sup.2 /g, and particle diameters ranging from about 1 to 50 microns; (ii) prilling said intimate admixture into spheroidal particulates and gelling the same; and then, (iii) recovering, drying and calcining said gelled particulates at a temperature of from 550.degree. to 1100.degree. C. The resultant particulates having bifold porosity are useful as catalysts or catalyst supports.

Spheroidal alumina particulates having bifold porosity and process for

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.

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Salindres, France

Gilbert Bouge