Abstract: A method for epoxidation of olefins with 2 to 6 C atoms, especially propene, with hydrogen peroxide in the gas phase at a temperature below 250° C. The reaction is carried out by bringing a gas mixture containing the olefin, hydrogen peroxide and water into contact with the catalyst from the series of compounds of an element of the 4th to the 6th subgroup of the periodic table or of arsenic or selenium and molecular sieves in the absence of a liquid phase. Titanium-containing molecular sleeves are preferred catalysts.

Abstract: Microporous and mesoporous metal silicates are prepared by the hydrothermal reaction of a silicon and metal source in the presence of a template. The choice of raw materials influences the purity and hence the catalytic activity of the products. A pyrogenic mixed oxide is used as the silicon and metal source. Prepared products have the composition (SiO2)1−x(AmOn)x, where A is Ti, Al, B, V or Zr and x is 0.005 to 0.1. Shaped objects of the microporous and mesoporous metal silicates are obtained directly by using a shaped object of the pyrogenic mixed oxide. The products obtained are used as oxidation catalysts.

Abstract: Granulates which contain titanium silicalite-1 are composed of silicon dioxide, titanium dioxide and titanium silicalite-1 crystals. The granulates can be prepared by spray-drying or spray granulating the crystallization suspension. The granulates may be used as suspension catalysts, such as for the epoxidation of olefins using hydrogen peroxide.

Abstract: Preparation of 2,3,5-trimethylhydroquinone diesters by rearrangement of 2,6,6-trimethylcyclohex-2-ene-1,4-dione (4-oxo-isophorone, ketoisophorone) in the presence of a solid, acid catalyst and an acylating agent, for example carboxylic acid anhydrides or carboxylic acid halides. The 2,3,5-trimethylhydroquinone diester may then optionally be saponified to the free 2,3,5-trimethylhydroquinone, which is a valuable building block in the synthesis of vitamin E.

Abstract: Titanium-containing molecular sieves are prepared by adding an aqueous template solution to a mixture of tetraalkyl orthosilicate and tetraalkyl orthotitanate, crystallizing the reaction mixture in an autoclave and separating the solid obtained optionally, the solid is washed and calcined. The titanium-containing molecular sieves can be used as catalysts, inter alia in the epoxidation of olefins.

Abstract: Microporous and mesoporous metal silicates are prepared by the hydrothermal reaction of a silicon and metal source in the presence of a template. The choice of raw materials influences the purity and hence the catalytic activity of the products. A pyrogenic mixed oxide is used as the silicon and metal source. Prepared products have the composition (SiO.sub.2).sub.1-x (A.sub.m O.sub.n).sub.x, where A is Ti, Al, B, V or Zr and x is 0.005 to 0.1. Shaped objects of the microporous and mesoporous metal silicates are obtained directly by using a shaped object of the pyrogenic mixed oxide. The products obtained are used as oxidation catalysts.