Vereinigte Aluminium-werke Aktiengesellschaft

Metallgesellschaft Aktiengesellschaft

Gunter Winkhaus

Roland Thome

Jorg F Greber

Lothar Reh

Arno Tissler

Hubert Bings

Harald Sauer

Peter Fischer

Klaus K Unger

Hubertus Schmidt

Hartmut Pietsch

Fritz Kampf

Wolfgang Turke

Hans Werner Schmidt

Dieter Moritz

Gerhard Wargalla

Synthetic crystalline aluminosilicate is prepared by an inorganic process from a reaction mixture, which contains, in an aqueous alkaline medium SiO.sub.2 and Al.sub.2 O.sub.3 or their hydrated derivatives or alkali silicates and aluminates, mineralizers and optionally seeding crystals, the reaction mixture containing: SiO.sub.2 /Al.sub.2 O.sub.3 in molar ratio of 15-40, OH.sup.- /SiO.sub.2 in molar ratio 0.1-0.2, and H.sub.2 O/SiO.sub.2 in molar ratio 20-60. The aluminosilicate produced by the process has a chemical composition expressed in molar ratios as: 0-3 M.sub.2 O:Al.sub.2 O.sub.3 :15-40 SiO.sub.2 :0-40 H.sub.2 O, where M represents an alkali cation. The aluminosilicate is useful in the preparation of catalysts and adsorbents.

Synthetic, crystalline aluminosilicate, method for its preparation as

The present invention relates to a modified form of alumina hydrate filler, thermosetting and thermoplastic compositions having improved workability and mechanical properties containing such filler and methods of manufacturing such modified alumina hydrate filler. More specifically, the invention provides for the admixture of modified alumina hydrate crystals with a resinous composition in which the individual alumina hydrate crystal edges are substantially rounded, have a mean crystal size of less than about 35 microns and less than about 0.1% by volume of alumina hydrate crystals have a diameter of less than 2 microns. The resulting compositions have improved viscosity properties and exhibit good bending strength and flame retardant characteristics.

Resinous compositions containing modified alumina hydrate crystals

A method for continuously extracting uranium from ores comprises the steps of forming a slurry of ore in a leaching solution; heating the slurry while pumping it through a tube reactor at high turbulences characterized by Reynolds numbers in excess of 50,000; supplying gaseous oxygen at high pressures of at least 30 bar into the tube reactor such that the uranium is substantially completely oxidized in a soluble form but impurities in the slurry are substantially kept from becoming soluble; recovering the uranium oxide solute which is substantially free of impurities.

Method for extraction of uranium from ores

Process for producing modified alumina hydrate crystals

A method of recovering fluorine, e.g. as hydrogen fluoride, from wastes of aluminum electrolysis furnaces, chemisorbents, adsorbents or absorbents, etc. in which the fluorine-containing material is subjected to pyrohydrolysis in an expanded fluid bed and the HF-containing gas is subjected to condensation or scrubbing for the removal of the HF therefrom. According to the invention, the exhaust gases from the fluidized bed are cooled by direct contact with solids which can be circulated in a separate cycle and are themselves cooled in a cooler, e.g. by contact with gas which is to be fed to the expanded fluidized bed. The circulated solids thus allow recovery of the sensible heat of the gas without diluting it.

Process for producing hydrogen fluoride

Growing community of inventors

Konigswinter, Germany

Gunter Winkhaus