HIGHLY DISPERSED METAL SUPPORTED OXIDE AS NH3-SCR CATALYST AND SYNTHESIS PROCESSES

1 . A method comprising using a catalyst material as an ammonia selective catalytic reduction (NH 3 -SCR) catalyst for nitrogen oxides (NOx) reduction, wherein said catalyst material being prepared by a process comprising the steps of:

(a) providing a support material having surface hydroxyl (OH) groups, wherein the support material is ceria (CeO 2 ), zirconia (ZrO 2 ) or a combination thereof, and wherein the support material contains at least 0.3 mmol and at most 2.0 mmol OH groups/g of the support material;

(b) reacting the support material having surface hydroxyl (OH) groups of step (a) with at least one of the following:

(b1) a compound containing at least one alkoxy or phenoxy group bound though its oxygen atom to a metal element from Group 5 (V, Nb, Ta) or Group 6 (Cr, Mo, W);

(b2) a compound containing at least one hydrocarbon group bound though a carbon atom to a metal element from Group 5 (V, Nb, Ta) or Group 6 (Cr, Mo, W);

(b3) a compound containing at least one hydrocarbon group bound though a carbon atom to a metal element which is copper (Cu); and

(c) calcining the product obtained in step (b) in order to provide a catalyst material in which a metal element from Group 5 or Group 6, or Cu, is present as an oxide on the support material.

2 . The method according to claim 1 , wherein the support material is a ceria (CeO 2 ) or ceria-zirconia (CeO 2 —ZrO 2 ) support.

3 . The method according to claim 1 , wherein the support material contains at least 0.5 mmol and at most 1.3 mmol OH groups/g of the support material.

4 . The method according to claim 1 , wherein the compound containing at least one alkoxy or phenoxy group bound though its oxygen atom to a metal element from Group 5 (V, Nb, Ta) or Group 6 (Cr, Mo, W) is at least one compound selected from the group consisting of: [Nb(OEt) 5 ] 2 ; Nb(OAr) 5 where Ar is the 1,3,5-trimethylphenyl (CH 3 ) 3 C 6 H 2 — group; [W=O(OEt) 4 ] 2 ; [V(═O)(OEt) 3 ] 2 ; [V(═O)(O i Pr) 3 ]; and [Ta(OEt) 5 ] 2 .

5 . The method according to claim 1 , wherein the compound containing at least one hydrocarbon group bound though a carbon atom to a metal element from Group 5 (V, Nb, Ta) or Group 6 (Cr, Mo, W) is at least one compound selected from the group consisting of: W≡C t Bu(CH 2 t Bu) 3 ; and Mo(O) 2 Mesityl 2 .

6 . The method according to claim 1 , wherein the compound containing at least one hydrocarbon group bound though a carbon atom to a metal element which is copper (Cu) is [Cu 5 (Mes) 5 ].

7 . The method according to claim 1 , wherein the temperature in calcining step (c) is at least 300° C., the duration of the calcining step being least 1 hour.

8 . The method according to claim 1 , wherein the temperature in calcining step (c) is at most 700° C., and/or the duration of the calcining step is at most 30 hours.

9 . The method according to claim 1 , wherein the compound obtained in step (b1) or (b2) has at least 0.1 wt % and at most 5.0 wt % of metal element from Group 5 (V, Nb, Ta) or Group 6 (Cr, Mo, W) or Cu, in elemental analysis of the compound obtained in step (b1) or (b2).

10 . The method according to claim 1 , wherein the compound obtained after calcining step (c) has at least 0.1 wt % and at most 5.0 wt % of metal element from Group 5 (V, Nb, Ta) or Group 6 (Cr, Mo, W) or Cu, in elemental analysis of the compound obtained after calcining step (c).

11 . The method according to claim 1 , comprising contacting the catalyst material with an exhaust gas stream comprising NOx gases, the catalyst material converting NOx gases in the exhaust gas stream to N 2 .