Rhone-Poulenc Industries

Rhone-Poulenc Specialites Chimiques

L'institut Francais Du Petrole

Regis Poisson

Thierry Dupin

Jean Lavina

Roland Jacques

Gilbert Bouge

Claude Magnier

Laurent Seigneurin

Bertrand Latourrette

Jean-Francois Colombet

Max Michel

Patrick Dougier

Jean-Philippe Browaeys

Provided is a process for preparing alumina agglomerates which comprises:

Alumina agglomerates and process for the preparation thereof

Process for the preparation of alumina agglomerates

Finely divided powders of alkaline earth metal titanates, well suited for the fabrication of, e.g., ceramic resistors and condensers, are facilely prepared by (i) admixing a solution of an alkaline earth metal nitrate with a titanium sol having a pH ranging from 0.8 to 2.5 and which comprises elementary crystallites of TiO.sub.2 having particle sizes ranging from 10 to 100 .ANG., agglomerated into submicronic masses having particle sizes ranging from 200 to 1000 .ANG., (ii) next drying the suspension which results, (iii) calcining said dried suspension at a temperature ranging from 700.degree. to 1300.degree. C. for from 30 minutes to 24 hours, under a NO.sub.x partial pressure decreasing from 1 to 0, and then (iv) optionally grinding the powder resulting from said step (iii).

Process of making finely divided powders of alkaline earth metal

Type Y zeolites were adopted as, e.g., catalysts and adsorbents, are facilely prepared by (i) intimately admixing, at essentially ambient temperature, an aqueous solution of a water-soluble aluminum compound with an aqueous solution of sodium silicate as to prepare a reaction mixture solution or sol therefrom, (ii) next heating said reaction mixture solution or sol to a temperature of crystallization, ranging from about 50.degree. to 120.degree. C., by heat exchange within such rapid period of time as to avoid any phase conversion thereof, but whereafter said reaction mixture solution or sol transforms essentially immediately into a gel, and (iii) thence maintaining the resulting gel at such crystallization temperature until Type Y zeolite crystals are crystallized therefrom.

Preparation of type Y zeolites

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

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

Spheroidal alumina shaped articles are prepared by dispersing an ungelled admixture of an alumina sol and hexamethylenetetramine, in the form of droplets, into a liquid forming medium which is but very slightly miscible with water, said medium being at a temperature of between about 50.degree. and 105.degree. C., next aging the alumina spheres thus shaped at a temperature greater than about 105.degree. C. at superatmospheric pressure, then secondarily aging said alumina spheres in a basic medium, and thence washing, drying and calcining said aged alumina spheres. The resultant shaped articles are useful, e.g., catalysts or catalyst carriers/supports.

Production of spheroidal alumina shaped articles

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.

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Regis Poisson