Hydrocarbon steam cracking catalyst, method for preparing the same and method for preparing light olefin by using the same
View Patent ↗Provided are a catalyst for hydrocarbon steam cracking for light olefin production and a method for preparing the same. The catalyst is a simple KMgPO 4 catalyst, a supported KMgPO 4 catalyst, or a KMgPO 4 -sintered catalyst. The supported KMgPO 4 catalyst is prepared by impregnating a carrier with an aqueous solution of a KMgPO 4 precursor and the KMgPO 4 -sintered catalyst is prepared by mixing a KMgPO 4 powder or a KMgPO 4 precursor powder with metal oxide followed by sintering. Provided is also a method for producing light olefins such as ethylene and propylene by steam cracking in the presence of the catalyst. When the catalyst comprising KMgSO 4 as a catalytic component is used in olefin production, the yield of olefins is increased and the amount of cokes deposited on the catalyst is reduced.
1. A method for preparing a catalyst for hydrocarbon steam cracking, which comprises:
dissolving a KMgPO 4 precursor in water to prepare an aqueous solution of the KMgPO 4 precursor;
impregnating a carrier with the aqueous solution of the KMgPO 4 precursor to prepare a supported catalyst; and
sintering the supported catalyst under 1,000-1,400 ° C. for 22-26 hours.
2. The method of claim 1 , wherein the KMgPO 4 precursor is prepared from magnesium nitrate hydrate, potassium hydroxide, and ammonium phosphate.
3. The method of claim 1 , wherein the carrier is selected from the group consisting of alpha-alumina, silica, silica-alumina, zirconium oxide, magnesium oxide, magnesium aluminate, calcium aluminate, and zeolite.
4. A method for preparing a catalyst for hydrocarbon steam cracking, which comprises:
mixing a KMgPO 4 powder or a KMgPO 4 precursor powder and metal oxide; and
sintering the resultant mixture under 1,000-1,400 ° C. for 22-26 hours to obtain a sintered catalyst of KMgPO 4 -metal oxide.
5. The method of claim 4 , wherein the metal oxide is selected from the group consisting of alpha-alumina, silica, silica-alumina, zirconium oxide, magnesium oxide, magnesium aluminate, calcium aluminate, and zeolite.
6. A method for producing olefins by steam cracking of hydrocarbons, wherein the method comprising;
providing hydrocarbons for steam cracking;
contacting the hydrocarbons with a catalyst,
wherein the catalyst is KMgPO 4 catalyst supported on a carrier,
wherein the catalyst is obtained by sintering KMgPO 4 and the carrier under 1,000-1,400 ° C. for 22-26 hours, and
wherein the concentration of KMgPO 4 in the catalyst is in a range of 0.5-30 wt % based on the total weight of the catalyst; and obtaining olefins,
wherein the olefins include ethylene having a range of 31.2 to 31.%, prophylene having a range of 17.1 to 17.2%, and cokes formed on a surface of the catalyst having a range of 0.62 to 3.37%.
7. A method for producing olefins by steam cracking of hydrocarbons, wherein the method comprising;
providing hydrocarbons for steam cracking;
contacting the hydrocarbons with a catalyst;
wherein the catalyst is KMgPO 4 catalyst,
wherein the catalyst is obtained by sintering a KMgPO 4 powder or a KMgPO 4 precursor powder and a metal oxide under 1,000-1,400° C. for 22-26hours, and
wherein the concentration of KMgPO 4 in the catalyst is in a range of 0.5-50 wt % based on the total weight of the catalyst; and
obtaining olefins,
wherein the olefins include ethylene having a range of 31.2 to 31.6%, prophylene having a range of 17.1 to 17.2%, and cokes formed on a surface of the catalyst having a range of 0.62 to3.37%.
8. The method of claim 7 , wherein the steam cracking is carried out at a reaction temperature of 600-1,000° C., a weight ratio of steam/hydrocarbons of 0.3-1.0, and LHSV (Liquid Hourly Space Velocity) of 1-20 hr −1 .
9. The method of claim 7 , wherein the steam cracking is carried out in a reactor selected from the group consisting of a fixed-bed reactor, a fluidized-bed reactor, and a mobile phase reactor.
10. The method of claim 7 , wherein the catalyst is regenerated by removal of cokes formed on a surface of the catalyst at 500-1,300° C. in the presence of air, steam, or a mixture thereof after the steam cracking.
11. The method of claim 6 , wherein the steam cracking is carried out at a reaction temperature of 600-1,000° C., a weight ratio of steam/hydrocarbons of 0.3-1.0, and LHSV (Liquid Hourly Space Velocity) of 1-20 hr −1 .
12. The method of claim 6 , wherein the steam cracking is carried out in a reactor selected from the group consisting of a fixed-bed reactor, a fluidized-bed reactor, and a mobile phase reactor.
13. The method of claim 6 , wherein the catalyst is regenerated by removal of cokes formed on a surface of the catalyst at 500-1,300° C. in the presence of air, steam, or a mixture thereof after the steam cracking.