›1.independentA process for producing shell catalysts comprising noble metals on a porous support, which comprises: impregnating the support with salt solutions of …+2
A process for producing shell catalysts comprising noble metals on a porous support, which comprises: impregnating the support with salt solutions of the noble metals; exposing the support to UV radiation so that the noble metals in the zone close to the surface are reduced to metals; and extracting the pellets in a solvent in order to remove the noble metal salts in the interior of the pellet which have not been irradiated.
›2.↳ 1The process as claimed in claim 1, wherein the noble metals are selected from the group consisting of Pd, Au, Pt, Ag, Rh, Ru, Os and Ir.d2
The process as claimed in claim 1, wherein the noble metals are selected from the group consisting of Pd, Au, Pt, Ag, Rh, Ru, Os and Ir.
›3.↳ 1The process as claimed in claim 1 wherein the noble metals are Au and Pd and the salts thereof which are used are the acetates.d2
The process as claimed in claim 1 wherein the noble metals are Au and Pd and the salts thereof which are used are the acetates.
›4.independentmultiple · 1, 2, 3The process as claimed in one of claims 1 to 3, wherein the support material used is SiO.sub.2, Al.sub.2 O.sub.3, TiO.sub.2, ZrO.sub.2 or a mixture th…
Multiple dependency — claims 1, 2, 3. Shown here under ; it stands on every one of them.
The process as claimed in one of claims 1 to 3, wherein the support material used is SiO.sub.2, Al.sub.2 O.sub.3, TiO.sub.2, ZrO.sub.2 or a mixture thereof.
›5.independentmultiple · 1, 2, 3The process as claimed in one of claims 1 to 3, wherein the UV photoreduction is carried out by irradiation with light having a wavelength of from 40 …+1
Multiple dependency — claims 1, 2, 3. Shown here under ; it stands on every one of them.
The process as claimed in one of claims 1 to 3, wherein the UV photoreduction is carried out by irradiation with light having a wavelength of from 40 to 400 nm.
›6.↳ 5The process as claimed in claim 5, wherein the UV photoreduction is carried out by irradiation with light having a wavelength of from 140 to 360 nm.d2
The process as claimed in claim 5, wherein the UV photoreduction is carried out by irradiation with light having a wavelength of from 140 to 360 nm.
›7.independentmultiple · 1, 2, 3The process as claimed in one of claims 1 to 3, wherein the photoreduction of the Pd and/or Au is carried out by irradiation with UV light having a po…+3
Multiple dependency — claims 1, 2, 3. Shown here under ; it stands on every one of them.
The process as claimed in one of claims 1 to 3, wherein the photoreduction of the Pd and/or Au is carried out by irradiation with UV light having a power density of from 0.01 to 100 W/cm.sup.2 from a lamp or a pulsed laser, where, when a pulsed laser is used, the pulse frequency is from 1 to 1000 pulses/s and the irradiation time is from 0.01 to 1000 s, while when a lamp is used the irradiation time is from 0.1 min to 100 min.
›8.↳ 7The process as claimed in claim 7, wherein the UV light has a power density of from 0.1 to 20 W/cm.sup.2.d2+2
The process as claimed in claim 7, wherein the UV light has a power density of from 0.1 to 20 W/cm.sup.2.
›14.↳ 8A shell catalyst obtainable by the process of claim 8, wherein the shell thickness is from 5 to 5000 .mu.m.d3
A shell catalyst obtainable by the process of claim 8, wherein the shell thickness is from 5 to 5000 .mu.m.
›19.↳ 8A process for preparing vinyl acetate in the gas phase from ethylene, acetic acid and oxygen or oxygen-containing gases in the presence of a catalyst …d3
A process for preparing vinyl acetate in the gas phase from ethylene, acetic acid and oxygen or oxygen-containing gases in the presence of a catalyst obtainable by a process as claimed in claim 8.
›9.independentmultiple · 1, 2, 3The process as claimed in one or more of claims 1 to 3, wherein the impregnated catalyst support is treated with UV sensitizers before irradiation.+1
Multiple dependency — claims 1, 2, 3. Shown here under ; it stands on every one of them.
The process as claimed in one or more of claims 1 to 3, wherein the impregnated catalyst support is treated with UV sensitizers before irradiation.
›13.↳ 9A shell catalyst obtainable by the process of claim 9, wherein the shell thickness is from 5 to 5000 .mu.m.d2
A shell catalyst obtainable by the process of claim 9, wherein the shell thickness is from 5 to 5000 .mu.m.
›10.independentmultiple · 1, 2, 3The process as claimed in one of claims 1 to 3 carried out without using a chemical reducing agent.+2
Multiple dependency — claims 1, 2, 3. Shown here under ; it stands on every one of them.
The process as claimed in one of claims 1 to 3 carried out without using a chemical reducing agent.
›15.↳ 10A shell catalyst obtainable by the process of claim 10, wherein the shell thickness is from 5 to 5000 .mu.m.d2
A shell catalyst obtainable by the process of claim 10, wherein the shell thickness is from 5 to 5000 .mu.m.
›20.↳ 10A process for preparing vinyl acetate in the gas phase from ethylene, acetic acid and oxygen or oxygen-containing gases in the presence of a catalyst …d2
A process for preparing vinyl acetate in the gas phase from ethylene, acetic acid and oxygen or oxygen-containing gases in the presence of a catalyst obtainable by a process as claimed in claim 10.
›11.independentmultiple · 1, 2, 3A shell catalyst obtainable by the process as claimed in one of claims 1 to 3, wherein the shell thickness is from 5 to 5000 .mu.m.+2
Multiple dependency — claims 1, 2, 3. Shown here under ; it stands on every one of them.
A shell catalyst obtainable by the process as claimed in one of claims 1 to 3, wherein the shell thickness is from 5 to 5000 .mu.m.
›12.↳ 11A shell catalyst as claimed in claim 11, wherein the noble metals present are Pd and/or Au.d2
A shell catalyst as claimed in claim 11, wherein the noble metals present are Pd and/or Au.
›18.↳ 11A process for preparing vinyl acetate in the gas phase from ethylene, acetic acid and oxygen or oxygen-containing gases in the presence of a catalyst …d2
A process for preparing vinyl acetate in the gas phase from ethylene, acetic acid and oxygen or oxygen-containing gases in the presence of a catalyst obtainable by a process as claimed in claim 11.
›16.independentmultiple · 1, 2, 3A process for hydrogenation or oxidation reactions in the presence of a catalyst obtainable by a process as claimed in one or more of claims 1 to 3.
Multiple dependency — claims 1, 2, 3. Shown here under ; it stands on every one of them.
A process for hydrogenation or oxidation reactions in the presence of a catalyst obtainable by a process as claimed in one or more of claims 1 to 3.
›17.independentmultiple · 1, 2, 3A process for preparing vinyl acetate in the gas phase from ethylene, acetic acid and oxygen or oxygen-containing gases in the presence of a catalyst …
Multiple dependency — claims 1, 2, 3. Shown here under ; it stands on every one of them.
A process for preparing vinyl acetate in the gas phase from ethylene, acetic acid and oxygen or oxygen-containing gases in the presence of a catalyst obtainable by a process as claimed in one of claims 1 to 3.
