Catalyst for the conversion of vehicular exhaust gases and process for preparing the catalyst

Claim 2

A catalyst adapted for the treatment of internal combustion engine exhaust gases, comprising a monolithic catalyst support impregnated with a plurality of catalytically active phases comprising a first catalytically active phase and a second catalytically active phase, one section of said support being impregnated with said first catalytically active phase which includes at least one rare earth and another section of said support being impregnated with said second catalytically active phase which includes at least one rare earth.

Claim 3

The catalyst as defined by claim 1, said monolithic catalyst support comprising a rigid substrate having a network of channels therethrough.

Claim 4

The catalyst as defined by claim 2, said rigid substrate having a layer of porous material deposited thereon.

Claim 5

The catalyst as defined by claim 3, said porous material comprising macroporous material.

Claim 6

The catalyst as defined by claim 3, said porous material comprising alumina.

Claim 7

The catalyst as defined by claim 1, said first and/or second catalytically active phase comprising at least one precious metal including platinum, palladium, rhodium and iridium.

Claim 8

The catalyst as defined by claim 1, said first and/or second catalytically active phase further comprising at least one metal including nickel, iron, zirconium, vanadium, chromium, tungsten, manganese, tin, germanium, cobalt, uranium and rhenium.

Claim 9

The catalyst as defined by claim 6, said first and/or second catalytically active phase further comprising at least one metal including nickel, iron, zirconium, vanadium, chromium, tungsten, manganese, tin, germanium, cobalt, uranium and rhenium.

Claim 10

The catalyst as defined by claim 7, said at least one metal being deposited onto the entirety of the exposed surface of the catalyst support.

Claim 11

The catalyst as defined by claim 6, said at least one precious metal being deposited onto less than the entirety of the exposed surface of the catalyst support.

Claim 12

The catalyst as defined by claim 7, said at least one metal being deposited onto less than the entirety of the exposed surface of the catalyst support.

Claim 13

The catalyst as defined by claim 10, wherein at least one different metal or precious metal is deposited onto exposed surface of the catalyst support not occupied by said at least one precious metal.

Claim 14

The catalyst as defined by claim 11, wherein at least one different metal precious metal is deposited onto exposed surface of the catalyst support not occupied by said at least one metal.

Claim 15

The catalyst as defined by claim 1, said first and said second catalytically active phases comprising differing concentrations of the same catalytically active metals and/or precious metals.

Claim 16

The catalyst as defined by claim 1, comprising at least one multifunctional catalytically active phase.

Claim 17

The catalyst as defined by claim 1, comprising at least one oxidizing catalytically active phase.

Claim 18

The catalyst as defined by claim 1, said catalyst support comprising a ceramic.

Claim 19

The catalyst as defined by claim 1, said catalyst support comprising a metal.

Claim 20

The catalyst as defined by claim 1, said catalyst support comprising a honeycomb.

Claim 21

The catalyst as defined by claim 3, said porous material comprising a refractory material.

Claim 22

The catalyst as defined by claim 20, said refractory material comprising aluminum oxide.

Claim 23

A process for the preparation of a catalyst adapted for the treatment of internal combustion engine exhaust gases, comprising a monolithic catalyst support impregnated with a plurality of catalytically active phases, one section of said support being impregnated with a first one of the catalytically active phases and another section of said support being impregnated with a second one of the catalytically active phases, comprising the steps of: (i) immersing said one section of the monolithic catalyst support in a predetermined volume of a first solution of a precursor of at least one element of said first catalytically active phase, the predetermined volume of said first solution being equal to the pore volume of the catalyst support impregnated thereby; (ii) manipulating said catalyst support such that said first solution is adsorbed onto the exposed surface of said one section thereof; (iii) immersing said another section of the monolithic catalyst support in a second solution of a precursor of at least one element of said second catalytically active phase, the volume of said second solution being at least equal to the pore volume of the catalyst support impregnated thereby; (iv) manipulating said catalyst support such that said second solution is adsorbed onto the exposed surface of said another section; and (v) drying and calcining the catalyst support thus impregnated.

Claim 24

A process for the preparation of a catalyst adapted for the treatment of internal combustion engine exhaust gases, comprising a monolithic catalyst support impregnated with a plurality of catalytically active phases, one section of said support being impregnated with a first one of the catalytically active phases and another section of said support being impregnated with a second one of the catalytically active phases, comprising the steps of: (i) immersing said one section of the monolithic catalyst support in a predetermined volume of a first solution of a precursor of at least one element of said first catalytically active phase, the predetermined volume of said first solution being equal to the pore volume of the catalyst support impregnated thereby; (ii) manipulating said catalyst support such that said first solution is adsorbed onto the exposed surface of said one section thereof; (iii) immersing said another section of the monolithic catalyst support in a second solution of a precursor of at least one element of said second catalytically active phase, the volume of said second solution being at least equal to the pore volume of the catalyst support impregnated thereby; (iv) manipulating said catalyst support such that said second solution is adsorbed onto the exposed surface of said another section; and (v) drying and calcining the catalyst support thus impregnated.

Claim 25

The process as defined by claim 22, wherein said catalyst support is coated with a porous material, and then dried and calcined prior to the impregnation thereof.

Claim 26

The process as defined by claim 22, comprising simultaneously impregnating said catalyst support with a plurality of elements constituting one of the catalytically active phases.

Claim 27

The process as defined by claim 22, comprising successively impregnating said catalyst support with the elements constituting one of the catalytically active phases.

Claim 28

The process as defined by claim 25, comprising drying and calcining said catalyst support after each successive impregnation.

Claim 29

The process as defined by claim 22, comprising simultaneously impregnating said catalyst support with elements common to said first and said second catalytically active phase.

Claim 30

The catalyst as defined by claim 1, wherein said first catalytically active phase includes platinum and said second catalytically active phase includes platinum and palladium.

Claim 31

The catalyst as defined by claim 1, wherein said rare earth comprises cerium.

Claim 32

The catalyst as defined by claim 1, wherein said first catalytically active phase includes platinum.

Claim 33

The catalyst as defined by claim 30, wherein said second catalytically active phase includes rhodium.

Claim 34

The catalyst as defined by claim 1, wherein said first catalytically active phase and said second catalytically active phase includes zirconium.

Claim 35

The catalyst as defined by claim 1, wherein said first catalytically active phase and said second catalytically active phase includes iron.

Claim 36

The catalyst as defined by claim 1, wherein said first catalytically active phase and said second catalytically active phase comprises at least one precious metal including platinum, palladium, rhodium and iridium.

Claim 37

The process as defined by claim 22, wherein said first catalytically active phase and said second catalytically active phase includes at least one rare earth.

Claim 38

The process as defined by claim 22, wherein said first catalytically active phase and said second catalytically active phase comprises at least one precious metal including platinum, palladium, rhodium and iridium.

Claim 39

The process as defined by claim 35, wherein said first catalytically active phase and said second catalytically active phase comprises at least one precious metal including platinum, palladium, rhodium and iridium.

Claim 40

The process as defined by claim 22, wherein said first catalytically active phase and said second catalytically active phase includes zirconium.

Claim 41

The process as defined by claim 22, wherein said first catalytically active phase and said second catalytically active phase includes iron.

Claim 42

The process as defined by claim 35, wherein said first catalytically active phase includes platinum and said second catalytically active phase includes rhodium.

Claim 43

The process as defined by claim 35, wherein said first catalytically active phase includes platinum and said second catalytically active phase includes platinum and palladium.

Claim 44

The process as defined by claim 22, wherein all of the impregnated elements comprising the first and second catalytically active phases are not calcined until step (V).

Claim 45

The process as defined by claim 22, wherein the predetermined volume is effective to impregnate less than the entire pore volume of the catalyst support.