Degussa Aktiengesellschaft

Degussa-h{umlaut Over (u)}ls Aktiengesellschaft

Akos Kiss

Peter K Kleinschmit

Dietrich Speer

Jenny Horst

Gunter Halbritter

Werner Volker

Elfriede Sextl

Eckehart Roland

Jens Weitkamp

Stefan Ernst

Thomas Kromminga

Thomas Bock

Juergen Hanich

Heike Kinz

Guenter Halbritter

Sems Yonsel

Christel Zell

Edgar Koberstein

Bernd Engler

Mustafa Siray

Michael Baacke

Frank Heindl

Stefan Stockhammer

Wiltrud Schafer-Treffenfeldt

Rita Loew

Reinhold Beand

Wiltrud Schaefer-Treffenfeldt

Peter Kleine-Mollhoff

Disclosed is a method for the purification of exhaust air and/or effluents, which may be exhausted, for example, from auto painting units or furniture lacquering units, involving contacting the air and/or effluents with a molded body. The molded body is made from dealuminated zeolite Y and at least one binder, which may be, for example, bentonites, kaolins, sepiolites or attapulgites, and having a hydrophobic factor of from 1.5 to 6.0, wherein a slurry of the binder in water does not exceed a pH of 10 and wherein the molded body is calcined at 850&deg; to 1100&deg; C. The molded body is produced by a process involving mixing pulverulent dealuminated zeolite Y with at least one binder, optionally with the addition of a lubricant and/or a pore former, and optionally with water or an organic solvent, moulding the resulting mass to form a molded body, and drying and calcining the molded bodies.

Method for the purification of exhaust air and/or effluents by contact with moulded bodies containing dealuminated zeolite Y

The invention relates to the removal of hydroxymonocarboxylic acids and tricarboxylic acids from aqueous solutions by adsorption on zeolites with a modulus of up to 400.

Process for isolating hydroxymonocarboxylic and tricarboxylic acids

Molecular sieves are modified by an ion exchange process where metal cations are introduced into the molecular sieves by means of solid state ion exchange. The solid state ion exchange can be carried out as follows: a weighed amount of calcined and activated zeolite is intimately mixed with a precalculated amount of PtCl.sub.2, PdCl.sub.2, RhCl.sub.3, CuCl.sub.2, V.sub.2 O.sub.5 or another compound of the noble metals (e.g., corresponding halides or oxides), the solids mixture is then heated in a current of inert gas (e.g., a current of helium gas or of nitrogen) to temperatures of 400.degree. to 600.degree. C., then cooled down to room temperature and subsequently reduced in a current of hydrogen for 10 to 14 hours at 280.degree. to 350.degree. C. in order to produce small metal clusters from the cationically introduced metal.

Method of modifying molecular sieves by means of solid state ion

Modified molecular sieves by means of solid ion exchange

Method of modifying molecular sieves by means of solid state ion exchange

A method for producing decorations which are color-stable in a porcelain firing (glost firing), and a pigment composition suitable for this method, is disclosed. Inclusion pigments based on heavy-metal sulfides and selenides in an oxidic or silicate casing, especially ZrSiO.sub.4, result in more color-stable decorations in a porcelain firing if color-stabilizing auxiliary agents from the series of Zn compounds, especially ZnO or zinc-containing glass frits, or cerium(III) or cerium(IV) compounds, especially CeO.sub.2, are used in the decorative layer and/or glaze layer as color-stabilizing auxiliary agents. The amount used in the decorative layer is generally 5 to 50% by weight in the case of ZnO and CeO.sub.2, relative to the inclusion pigment. The pigment composition contains at least one of the color-stabilizing auxiliary agents in addition to an inclusion pigment.

Method of producing decorations which are color-stable in a porcelain

Inclusion pigments are discolored having zirconium silicate as a casing component and chromium (III) oxide (Cr.sub.2 O.sub.3) as a discrete, included color compound. The included Cr.sub.2 O.sub.3 has a D.sub.50 value in the range of 0.1 to 3.0 .mu.m and a brilliant light green color. Contrary to non-included Cr.sub.2 O.sub.3 of identical value, the pigments of the present invention may be used for the preparation of decorations without problems and difficulties in their application and maintaining sharp lines and contours. The pigments are suitable for direct pressing and high temperature firing processes. They are prepared by fusing a mixture of zirconium dioxide, silicon dioxide, mineralizators and chromium oxide.

Inclusion pigments of zirconium silicate with included chromic oxide, a

A process for the production of moulded bodies from dealuminated Y-zeolite (SiO.sub.2 /Al.sub.2 O.sub.3 &gt;20) in which the microporous system of the zeolites and its characteristic adsorption properties are preserved and a binder whose slurry in water does not exceed a pH of 10 used in quantities of from 2 to 40%, based on the quantity of zeolite mass put into the process.

Molded bodies containing dealuminated zeolite Y and the process for

A process for the separation of amino acids from aqueous solutions by adsorption on zeolites of different types. It is unnecessary to separate the biomass prior to the treatment.

Process for the separation of amino acids from aqueous solutions

Brown spinel pigments based on zinc chromite which are iron-free and exhibit an atomic ratio of chromium to zinc in a range of 1 to greater than 0.5 up to 2 are disclosed. Preferred pigments additionally contain manganese, in which instance the atomic ratio of Mn to Cr is a maximum of 0.2. The production of the pigments involves a firing process of a powder mixture consisting of the oxides the metals, or precursors thereof, contained in the pigment. Instead of previously known grayish-brown unattractive products, attractive brown pigments are obtained by means of the selected molar ratio and a baking temperature above 1200.degree. C. The novel pigments can be used in the presence of glass frits even at firing temperatures above 1200.degree. C. to 1500.degree. C. and are suitable for a common firing of ceramic carrier and decoration.

Brown spinel pigments based on zinc chromite, method of their production

Inclusion pigments are disclosed based on zirconium silicate as a casing component and cobalt-free spinels as discrete, included colored compounds. The inclusion pigments are prepared by fusing a mixture of a zirconium dioxide source, a silicon dioxide source, one or more mineralizer and cobalt-free oxides in a ratio suitable for spinel-formation. The inclusion pigments have high enamel-fastness and high color-fastness. Further, the pigments are drain-resistant under usual decoration firing conditions.

Inclusion pigments of zirconium silicate formed with spinel inclusions,

Disclosed are neutral blue zirconium-vanadium pigments which do not display the disadvantages of previously known generic pigments, namely the high green component and the low color intensity and insufficient reproducibility in the case of neutral blue pigments. The neutral blue pigments with a rather high color intensity and good reproducibility are doped in the host lattice with phosphorus in addition to vanadium and are characterized by their color values in the CIE L*a*b* system. In order to produce such pigments, a zirconium-free mixture of powdery ZrO.sub.2, an SiO.sub.2 source, a vanadium compound and a phosphorus compound with an atomic ratio of Zr:Si:V:P=1:(0.95-1.10):(0.05-0.20):(0.005-0.03) as well as of a fluoride mineralizer is annealed after intensive grinding at 700.degree. to 900.degree. C.

Neutral blue zirconium-vanadium pigments

An aqueous suspension of zeolite NaY is treated in with sodium hydroxide solution. The treated zeolite NaY is subsequently dealuminized with silicon tetrachloride.

Method of preparing zeolite Y

Gray-black inclusion pigments are made using zirconium silicate as the encasing substance and carbon black particles as the inclusion phase by annealing a mixture of zirconium dioxide, a source for silicon dioxide, carbon black and mineralizers under reducing conditions at 900.degree.-1400.degree. C. The process uses zeolites with an SiO.sub.2 /Al.sub.2 O.sub.3 molar ratio of more than 4, preferably more than 10, as the SiO.sub.2 source. The depth of the color can be increased by also using an adhesion agent, especially silicon oil. The use of the zeolites facilities the employment of different zirconium dioxide qualities and permits the production of pigments with higher carbon black inclusion rates.

Method for making grey-black inclusion pigments

Coated spinel color pigments with a core of a colored spinel, in particular CoAl.sub.2 O.sub.4, and a coating glassy layer of a silicate are described. The coating layer is essentially silicon dioxide and one or more oxides of the group of alkali metals, alkaline earth metals, and/or earth metals show a high resistance to bleeding in the presence of glass fluxes, as compared to uncoated spinels. The pigments are produced by sintering, for 0.5 to 5 hours, a powder mixture of the spinel, silicon dioxide, and at least one member chosen from the group of alkali metal halides, alkaline earth metal halides, earth metal halides and mixtures thereof as mineralizer at 900.degree. to 1,300.degree. C. The coated spinel color pigments are suitable for the production of ceramic decorations with improved contour sharpness.

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Alzenau-Wasserlos, Germany

Akos Kiss