Catalyst direct conversion of methane to ethane and ethylene
View Patent ↗The present invention relates to an improved catalyst for direct conversion of methane to ethane and ethylene, a method for producing the catalyst and a process making use of the catalyst.
1. A catalyst for conversion of methane to a C 2 hydrocarbon, said catalyst comprising:
a) a manganese (Mn) oxide, in combination with an alkali metal and tungsten on a silica support; and
b) niobium (Nb) as a promoter.
2. The catalyst of claim 1 , wherein the catalyst further comprises one or more of Eu (Europium), Y (yttrium) and Nd (neodymium).
3. The catalyst of claim 1 , wherein the niobium (Nb) is present in an amount of 0.5 to 5% by weight.
4. The catalyst of claim 3 , wherein the niobium (Nb) is present in an amount of 1.2 to 4% by weight.
5. The catalyst of claim 4 , wherein the niobium (Nb) is present in an amount of 1.9 by weight.
6. The catalyst of claim 3 , wherein the catalyst further comprises one or more of Eu (Europium), Y (yttrium) and Nd (neodymium).
7. The catalyst of claim 1 , wherein the niobium is present as niobium oxide.
8. The catalyst of claim 1 , wherein the catalyst comprises manganese oxide, tungsten, and sodium as the alkali metal.
9. The catalyst of claim 8 , wherein part a) comprises 1.8% manganese oxide, 1.8% sodium oxide and 2.8% tungsten oxide by weight, with the rest silica.
10. The catalyst of claim 1 , wherein the catalyst comprises tungsten, an alkali metal, and an additional metal oxide in addition to manganese oxide.
11. The catalyst of claim 1 , wherein the alkali metal is sodium.
12. The catalyst of claim 1 , wherein the catalyst is prepared by the following process:
a) combining silica with a solution of a soluble manganese salt and a solution of sodium tungstate to obtain a precipitate;
b) drying the precipitate;
c) calcining the precipitate to obtain particles;
d) reducing the size of the particles;
e) combining the particles of step (d) with a solution of a niobium compound to obtain a precipitate; and
f) repeating steps (b), (c) and (d).
13. A process for converting methane to a C 2 hydrocarbon comprising the steps of
a) contacting a mixture of methane, oxygen and an inert gas with the catalyst of claim 1 to obtain the C 2 hydrocarbon; and
b) recovering the C 2 hydrocarbon.
14. The process of claim 13 , wherein the C 2 hydrocarbon recovered is a mixture of ethane and ethylene.
15. The process of claim 13 , wherein the process is carried out at a temperature of 600-900° C.