Abstract: A process for the preparation of zeolites of the ZSM-5 structural type from a mixture of SiO.sub.2 and Al(OH).sub.3 by hydrothermal crystallization in an aqueous amine solution, in the absence of alkali, at from 100.degree. to 200.degree. C., wherein the crystallization is carried out in the presence of a triamine, tetraamine and/or higher amine and the reaction mixture is formulated to have an SiO.sub.2 /Al.sub.2 O.sub.3 molar ratio defined by an equation which involves the chain length and number of amine groups of the amine employed, as well as to have certain molar ratios of H.sub.2 O/amine and amine/Al.sub.2 O.sub.

Abstract: Crystalline isotactic zeolites having the composition2/.pi.R.multidot.W.sub.2 O.sub.3 .multidot.m YO.sub.2 .multidot.p H.sub.2 Owhere R is an organic amine and n is the number of amine groups in the amine molecule, W is one or more of the elements B, Al, Ga and Fe and Y is Si and/or Ge, and a process for the preparation of these crystalline isotactic metal silicate zeolites from mixtures of YO.sub.2 and W(OH).sub.3 by hydrothermal crystallization at from 100.degree. to 200.degree. C. with the aid of an organic amine, in the absence of an alkali metal base, alkaline earth metal base or quaternary nitrogen base or their intermediates, the number m depending on the chain length of the organic amine used in the crystallization.

Abstract: A process for the manufacture of acicular ferrimagnetic iron oxide by heating iron(III) oxide or iron(III) oxide hydroxide at 220.degree.-460.degree. C. under a water vapor partial pressure of not less than 30 mbar, reducing the resulting product to magnetite by means of hydrogen and/or CO and/or an organic compound which can decompose in the presence of iron oxide, and then oxidizing the magnetite with an oxygen-containing gas to give acicular ferrimagnetic iron oxide of the formula FeO.sub.X, where X is from 1.33 to 1.50.

Abstract: A process for the manufacture of acicular ferromagnetic iron particles by heating a goethite, provided with a shape-stabilizing surface coating, at 250.degree.-450.degree. C. in an atmosphere containing water vapor at a partial pressure of not less than 30 mbar, to give alpha-iron(III) oxide, and reducing this material with hydrogen at 275.degree.-425.degree. C., and the use of the iron particles thus obtained as magnetic material in the production of magnetic recording media.

Abstract: A crystalline SiO.sub.2 --modification, which is characterized by an X-ray diffraction diagram having certain diffraction lines, and a process for the preparation of this crystalline SiO.sub.2 --modification by crystallizing reactive amorphous SiO.sub.2 under hydrothermal conditions in the presence of hexamethylenediamine. Sodium ions, phosphate ions and/or sulfate ions may be added for the crystallization.

Abstract: A process for the manufacture of acicular ferromagnetic iron particles by reducing an iron(III) oxide which carries a shape-stabilizing surface coating and has been produced by heating acicular iron(III) oxide hydroxide at 250.degree.-390.degree. C. in an atmosphere containing water vapor at a partial pressure of not less than 30 mbar, with hydrogen at 275.degree.-425.degree. C.

Abstract: A process for the manufacture of a bifunctional catalyst for the conversion of hydrocarbons, which contains a crystalline aluminosilicate of the type of the Y-zeolites as the acidic component and a noble metal as the hydrogenation component. The process constitutes a technologically simple way of manufacturing bifunctional zeolite catalysts which have at least the same activity and the same life as the catalysts manufactured by conventional methods, coupled with great heat stability and exhibit activity in the presence of H.sub.2 O, H.sub.2 S and NH.sub.3 at relatively high temperatures.

Abstract: Diesters of olefinically unsaturated 1,2- and/or 1,4-diols are prepared by reacting a conjugated diolefin, oxygen and a fatty acid, in the gas phase or liquid phase, over a solid catalyst which contains palladium and/or platinum and a further metal, which has an atomic number of from 21 to 30, from 39 to 48 or from 57 to 80, but is not a platinum metal, the catalyst having been obtained by reduction of compounds, applied to a carrier, of platinum and/or palladium and the further metal, and heating at 400.degree. C. or above.

Abstract: Alkali metal beryllo-alumino-silicates of the mordenite type form, under hydrothermal conditions (100.degree.-300.degree. C in a Carius tube), from aqueous mixtures containing the structural components SiO.sub.2, Al.sub.2 O.sub.3 and BeO and alkali metal hydroxides. In beryllium-containing mordenites, ratios of SiO.sub.2 to Al.sub.2 O.sub.3 of from 10:1 to 120:1 may be achieved, whereas values of only up to 10:1 are known in the pure alumino-silicates of this type. The alkali metal beryllo-alumino-silicates are accessible to ion exchange in the same way as the beryllium-free representatives. The so-called NH.sub.4 - and H-forms obtaineable by ion exchange may be used for the synthesis of highly active sorption compositions or catalysts after calcination.

Abstract: A two-stage process for the manufacture of methane from hydrocarbons is described. In the first stage, the hydrocarbons are converted into methane-rich gases, using the nickel catalyst described below. The cracked gases thus obtained are cooled and converted into methane-rich gases in a further catalytic process stage, using a methanization catalyst or the nickel catalyst mentioned below. To produce the nickel catalyst, the compound Ni.sub.6 Al.sub.2 (OH).sub.16.CO.sub.3.4H.sub.2 O is prepared in aqueous solution. The catalyst is obtained from this compound by drying, calcination and subsequent reduction in a stream of hydrogen whilst maintaining very specific temperature gradients between the drying stage and the calcination stage.

Abstract: The compound Ni.sub.6 Al.sub.2 (OH).sub.16. CO.sub.3. 4H.sub.2 O is isolated from aqueous solution. The catalyst is obtained from this compound by drying, calcination and subsequent reduction in a stream of hydrogen, whilst maintaining very specific temperature gradients between the drying stage and the calcination stage. A process for the manufacture of gases containing methane from hydrocarbons by steam cracking, in which the abovementioned catalyst is employed, is also described.