Degussa Aktiengesellschaft

Degussa - Huls Ag

Gustaaf Goor

Wolfgang Kunkel

Peter Panster

Stefan Wieland

Georg Thiele

Steffen Hasenzahl

Georg Markowz

Rainer Siegmeier

Jürgen Glenneberg

Eugen Staab

Jorg Kemnade

Mathias Viandt

Eckehart E Roland

Peter Goetz

Ulrich Brand

Hans Birkenbeil

The invention concerns a process for the preparation of hydrogen peroxide by the anthraquinone cyclic process. The process includes a regeneration stage in which working solution is regenerated by being brought into contact with an aqueous solution containing an alkyl anthrahydroquinone and/or an alkyl tetrahydroanthrahydroquinone in deprotonated form. The working solution regenerated in the regeneration stage is returned to the cyclic process.

Process for the preparation of hydrogen peroxide by the anthraquinone cyclic process

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.

Granulates which contain titanium silicalite-1

A method is shown for the separation of catalyst-free working solution from working solution, containing noble-metal black, especially palladium black as catalyst, of the hydrogenation cycle of the so-called anthraquinone method for the production of hydrogen peroxide by filtration of the catalyst-containing working solution using filter candles. The filter candles are formed of an open-pore support body based on a carbon material or metallic or ceramic material with an average pore width in a range of 5 to 100 .mu.m and of a single-layer or multi-layer membrane of ceramic material with an average pore width in a range of at least about 1 up to 10 .mu.m located on the outside surface of the support body.

Method of separating catalyst-free working solution from the

The invention relates to polymeric organosiloxane ammonium salts having a silica-like skeleton and including units of Formula (I): ##STR1## wherein R.sup.1 and R.sup.2 are identical or different and signify a group of Formula (II): ##STR2## wherein R.sup.5 is an alkylene group and the oxygen atoms are saturated by silicon atoms of additional groups corresponding to Formula (II), optionally with the insertion of cross-linking agents; R.sup.3 represents groups corresponding to R.sup.1 or R.sup.2, or hydrogen or an alkyl group; R.sup.4 represents hydrogen or an alkyl group; x is the charge number of an oxo anion of a monooxo-, isopolyoxo- or heteropolyoxo acid of the elements vanadium, niobium, tantalum, molybdenum or tungsten; and oxo groups of the X anion also may be replaced by peroxo groups. The invention also includes methods of preparing the salts of Formula (I) from salts of the type (R.sup.1 R.sup.2 R.sup.3 R.sup.4 N.sup.+).sub.y Y wherein Y is different from X. The invention further includes the use of the salts of Formula (I) as catalyst for oxidation reactions using peroxo compounds as an oxidation agent.

Process for preparing glycide by epoxidation using polymeric

An aqueous hydrogen peroxide extract which contains small amounts of dispersed working solution and a working solution which contains small amounts of dispersed aqueous hydrogen peroxide are collected in the extraction stage of the anthraquinone method for preparing hydrogen peroxide. In order to purify these solutions, the working solution is compounded with aqueous hydrogen peroxide or preferably with water and the hydrogen peroxide extract is compounded with an organic dissolving mixture, preferably a quinone dissolver, and the respective dispersed phase is separated out with the aid of coalescers in a separator unit. It is especially preferable to add 1-3% by volume water or 1-3% quinone dissolver before the coalescer stages and to use coalescers with a drop-enlarging design and filter layers consisting of thermally desized glass filament yarn. The after-purification in accordance with the method results in a hydrogen peroxide which is improved as regards carbon content and color index as well as in an increase in yield of hydrogen peroxide and in a working solution with constant rel. moisture.

Method of preparing hydrogen peroxide

Tetra substituted ureas wherein at least one substituent is an aryl group have proven very oxidation resistant in the anthraquinone process for making hydrogen peroxide. The urea nitrogen is directly attached to the aryl group. These ureas can be used as a single solvent or as a component of a mixture of solvents.

Process for the production of hydrogen peroxide

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Hanau, Germany

Gustaaf Goor