Method of preparing multicomponent bismuth molybdate catalysts comprising four metal components and method of preparing 1,3-butadiene using said catalysts
View Patent ↗A method of preparing multicomponent bismuth molybdate catalysts composed of four metal components and a method of preparing 1,3-butadiene using the catalyst, and particularly, to multicomponent bismuth molybdate catalysts composed of a divalent cationic metal, a trivalent cationic metal, bismuth and molybdenum, a preparation method thereof, and a method of preparing 1,3-butadiene from a C4 mixture including n-butene and n-butane using oxidative dehydrogenation are described.
1. A method of preparing a multicomponent bismuth molybdate catalyst, comprising:
a) preparing a first solution including a precursor of a trivalent cationic metal including iron, a precursor of a divalent cationic metal selected from the group consisting of magnesium, manganese, cobalt, nickel, copper, zinc, and a bismuth precursor;
b) preparing a second solution, in which a molybdenum precursor is dissolved;
c) adding the first solution in droplets to the second solution so that coprecipitation occurs, thus obtaining a coprecipitated solution;
d) subjecting the coprecipitated solution to stirring for about 1 to about 2 hours and then dewatering, thus obtaining a solid component; and
e) subjecting the solid component to drying at 150-200° C. and then thermal treatment at 400-600° C.,
wherein the multibismuth molybdate catalyst consists of four (4) metal components of the trivalent cationic metal, the divalent cationic metal, bismuth and molybdenum; and
wherein a molar ratio of the precursor of the divalent cationic metal:the precursor of the trivalent cationic metal:bismuth precursor:molybdenum precursor is about 7 to about 10:2-4:1:5-20.
2. The method according to claim 1 , wherein a molar ratio of the precursor of the divalent cationic metal:the precursor of the trivalent cationic metal:bismuth precursor:molybdenum precursor is 9:3:1:12.
3. A method of preparing 1,3-butadiene, comprising:
a) packing a reactor with a fixed bed of the bismuth molybdate catalyst prepared according to claim 1 ;
b) performing oxidative dehydrogenation while continuously passing reactants comprising a C4 mixture including n-butene, air, and steam through the catalyst bed of the reactor; and
c) obtaining 1,3-butadiene.
4. The method according to claim 3 , wherein the reactants are composed of n-butene, air and steam in a molar ratio of 1:about 0.5 to about 10:about 1 to about 50.
5. The method according to claim 3 , wherein the oxidative dehydrogenation is performed at a reaction temperature of 300-600° C. and a gas hourly space velocity of about 50 to about 5000 h −1 on the basis of n-butene.
6. A method of preparing 1,3-butadiene, comprising:
a) packing a reactor with a fixed bed of the bismuth molybdate catalyst prepared according to claim 2 ;
b) performing oxidative dehydrogenation while continuously passing reactants comprising a C4 mixture including n-butene, air, and steam through the catalyst bed of the reactor; and
c) obtaining 1,3-butadiene.
7. The method according to claim 6 , wherein the reactants are composed of n-butene, air and steam in a molar ratio of 1:about 0.5 to about 10:about 1 to about 50.
8. The method according to claim 6 , wherein the oxidative dehydrogenation is performed at a reaction temperature of 300-600° C. and a gas hourly space velocity of about 50 to about 5000 h −1 on the basis of n-butene.