Ruthenium promoter catalyst compositions
The present disclosure relates to ruthenium promoter catalyst compositions. The ruthenium promoter catalyst compositions comprise ruthenium metal species, an oxide support material, and a promoter species independently selected from the group consisting of La, Rb, Y, Yb, K, Cs, and Ba, or hydroxides, nitrates or oxides thereof. The present disclosure also relates to various methods, processes, systems, membranes and/or reactors, which can utilise the ruthenium promoter catalyst compositions, for example in ammonia synthesis.
1 . A catalyst composition comprising one or more catalyst hybrid particles and a transport promoter species,
wherein each catalyst hybrid particle comprises a ruthenium metal species, an oxide support particle having an average particle size from about 5 nm to about 10 μm, and one or more catalytic promoter species each independently selected from the group consisting of La, Rb, Y, Yb, K, Cs, and Ba, or hydroxides, nitrates or oxides thereof, wherein the ruthenium metal species and one or more catalytic promoter species are supported on the oxide support particle,
wherein the transport promoter species is in the form of a plurality of particles, and
wherein the transport promoter species comprises a metal species selected from the group consisting of molybdenum, tungsten, iron, cobalt, boron, chromium, tantalum, osmium, palladium, platinum, nickel, and combinations thereof.
2 . The catalyst composition of claim 1 , wherein the catalytic promoter species are each independently selected from the group consisting of K, Cs, and Ba, or hydroxides, nitrates or oxides thereof.
3 . The catalyst composition of claim 1 , wherein the oxide support particle is selected from the group consisting of magnesia, ceria, silica, zirconia, titania, alumina, and any combinations thereof.
4 . The catalyst composition of claim 1 , wherein the oxide support particle is ceria.
5 . The catalyst composition of claim 1 , wherein each catalyst hybrid particle comprises a ceria support particle, one or more ruthenium metal particles, and a catalytic promoter species independently selected from the group consisting of K, Cs, and Ba, or hydroxides, nitrates or oxides thereof.
6 . The catalyst composition of claim 1 , wherein the catalytic promoter species are in contact with the ruthenium metal particles.
7 . The catalyst composition of claim 1 , wherein the ruthenium metal species is supported on the oxide support particle in an amount of between about 1 to 15 wt % compared to the weight of oxide support particle.
8 . The catalyst composition of claim 1 , wherein the molar ratio of the catalytic promoter species to the ruthenium metal species is between about 1:10 to about 1:1.
9 . The catalyst composition of claim 1 , wherein the ruthenium metal species are ruthenium metal nanoparticles having a particle size of from about 1 nm to about 30 nm.
10 . The catalyst composition of claim 1 , wherein the transport promoter species is a palladium metal species.
11 . A nitrogen species selectively permeable solid membrane (NSPM) formed from a nitrogen permeable material or hydrogen species selectively permeable solid membrane (HSPM) formed from a hydrogen permeable material, wherein the NSPM or HSPM comprises a coating on at least one side thereof comprising a catalyst composition according to claim 1 .
12 . A process for synthesis of a product by reaction of at least a first reactant comprising a nitrogen or hydrogen species with a second reactant, the process comprising:
(i) providing a nitrogen or hydrogen species selectively permeable solid membrane (NSPM or HSPM) according to claim 11 , having a nitrogen or hydrogen species receiving side, respectively, and a product synthesis side;
(ii) providing a nitrogen or hydrogen species source at the nitrogen or hydrogen species receiving side, respectively;
(iii) providing a second reactant source at the product synthesis side;
(iv) providing a concentration gradient or a partial pressure differential of the nitrogen or hydrogen species source across the NSPM or HSPM, respectively, such that the concentration of nitrogen or hydrogen is lower on the product synthesis side than on the nitrogen or hydrogen species receiving side to thereby effect migration of the nitrogen or hydrogen species through the NSPM or HSPM, respectively, for reaction as the first reactant with the second reactant at or near the surface of the product synthesis side.