HYDROCARBON CONVERSION PROCESS

Abstract

The present invention relates to a hydrocarbon conversion process comprising contacting a hydrocarbon feed stream with a hydrocarbon conversion catalyst, wherein the hydrocarbon conversion catalyst comprises a first composition comprising a dehydrogenation drogenation active metal on a solid support; and a second composition comprising a transition metal and a doping agent on an inorganic support, wherein the doping agent is selected from zinc, gallium, indium, lanthanum, and mixtures thereof.

Claims

1. A hydrocarbon conversion process comprising contacting a hydrocarbon feed stream with a hydrocarbon conversion catalyst, wherein the hydrocarbon conversion catalyst comprises: a first composition comprising a dehydrogenation active metal on a solid support; and a second composition comprising a transition metal and a doping agent on an inorganic support, wherein the doping agent is selected from zinc, gallium, indium, lanthanum, and mixtures thereof.

2. The hydrocarbon conversion process according to claim 1, wherein the dehydrogenation active metal is selected from platinum, palladium, iridium, chromium, and mixtures thereof.

3. The hydrocarbon conversion process according to claim 1, wherein the solid support is selected from aluminium oxide, silicon dioxide, zirconium dioxide, titanium dioxide, magnesium oxide, calcium oxide, and mixtures thereof.

4. The hydrocarbon conversion process according to claim 1, wherein the transition metal is selected from molybdenum, tungsten, rhenium, and mixtures thereof.

5. The hydrocarbon conversion process according to claim 1, wherein the inorganic support is selected from aluminium oxide, silicon dioxide, zirconium dioxide, titanium dioxide, zeolite, and mixtures thereof.

6. The hydrocarbon conversion process according to claim 1, wherein the second composition further comprises a mixed magnesium-aluminium oxide or a mixed calcium-aluminium oxide.

7. The hydrocarbon conversion process according to claim 1, wherein the second composition contains tungsten oxide and a doping agent selected from zinc, gallium, indium, lanthanum, and mixtures thereof on an inorganic support comprising a mixture of silicon dioxide and Y-zeolite physically mixed with a mixed magnesium-aluminium oxide.

8. The hydrocarbon conversion process according to claim 1, wherein the second composition contains 0.1 to 10 wt % of the doping agent based on the total weight of the second composition.

9. The hydrocarbon conversion process according to claim 1, wherein the first composition and the second composition are physically mixed.

10. The hydrocarbon conversion process according to claim 1, wherein the hydrocarbon feed stream comprises a paraffin selected from ethane, propane, butane, pentane, and mixtures thereof.

11. The hydrocarbon conversion process according to claim 1, wherein the hydrocarbon conversion process is carried out at a temperature in the range of 200-800 C.

12. The hydrocarbon conversion process according to claim 1, wherein the hydrocarbon conversion process is performed in a fixed bed.

13. The hydrocarbon conversion process according to claim 1, wherein the hydrocarbon conversion catalyst is pretreated by contacting the catalyst system with an inert gas, an oxidizing gas, a reducing gas, or mixtures thereof, at a temperature in the range of 250 C. to 850 C. prior to contacting the hydrocarbon feed stream with the hydrocarbon conversion catalyst.

14. The hydrocarbon conversion process according to claim 1, wherein the hydrocarbon conversion process further comprises a regeneration step carried out by contacting the hydrocarbon conversion catalyst with an oxidizing gas at a temperature in the range of 200-700 C.

Description

EXPERIMENTAL RESULTS

[0060] In the examples section below, the conversion of propane into olefins, preferably ethylene and butene, has been investigated using a hydrocarbon conversion catalyst according to the present invention and a comparative catalyst.

EXAMPLE 1 COMPARATIVE

[0061] A solution of chloroplatinic acid hexahydrate and a solution of ytterbium trinitrate are co-impreganted onto powder of silica-zirconia mixture, then the resulting material was dried at 100 C. for 2 hours, followed by calcination under air at 700 C. for 3 hours to obtain a first composition containing 1 wt % Pt and 0.15 wt % Yb and balancing SiO.sub.2-ZrO.sub.2, wherein the weight percentages based on the total weight of the first composition.

[0062] A support for a second composition was prepared by mixing SiO.sub.2 with HY-Zeolite. The SiO.sub.2-Zeolite support was then impregnated using a solution of ammonium metatungstate hydrate, then dried at 110 C. for 3 hours. The resulted material was then mixed with MgAlCO3 layered double hydroxide followed by calcination under air at 550 C. for 2 hours to obtain a second composition containing 7 wt % W, 4 wt % Y-zeolite, 9 wt % MgAl oxide, and balancing SiO2, wherein the weight percentages are based on the total weight of the second composition.

[0063] The first composition and the second composition were physically mixed 1:1 by weight to obtain Example 1 catalyst.

EXAMPLE 2

[0064] A first composition is prepared the s y as described in Example 1.

[0065] A support for a second composition was prepared by mixing SiO.sub.2 with HY-Zeolite. The SiO.sub.2-Zeolite support was then impregnated using a solution of ammonium metatungstate hydrate, then dried at 110 C. for 3 hours. The dried mixture was then impregnated using a solution of zinc nitrate hexahydrate, then left to dry once again at 110 C. for 3 hours. The resulted material was then mixed with MgAlCO3 layered double hydroxide followed by calcination under air at 550 C. for 2 hours to obtain a second composition containing 7 wt % W, 4 wt % Zn, 4 wt % Y-zeolite, 9 wt % MgAl oxide, and balancing SiO2, wherein the weight percentages are based on the total weight of the second composition.

[0066] The first composition and the second composition were physically mixed 1:1 by weight to obtain Example 2 catalyst.

EXAMPLE 3

[0067] A first composition is prepared the same way as described in Example 1.

[0068] A support for a second composition was prepared by mixing SiO.sub.2 with HY-Zeolite. The SiO.sub.2-Zeolite support was then impregnated using a solution of ammonium metatungstate hydrate, then dried at 110 C. for 3 hours. The dried mixture was then impregnated using a solution of indium trinitrate, then left to dry once again at 110 C. for 3 hours. The resulted material was then mixed with MgAlCO3 layered double hydroxide followed by calcination under air at 550 C for 2 hours to obtain a second composition containing 7 wt % W, 2 wt % In, 4 wt % Y-zeolite, 9 wt % MgAl oxide, and balancing SiO2, wherein the weight percentages are based on the total weight of the second composition.

[0069] The first composition and the second composition were physically mixed 1:1 by weight to obtain Example 3 catalyst.

EXAMPLE 4

[0070] A first composition is prepared the same way as described in Example 1.

[0071] A support for a second composition was prepared by g SiO.sub.2 with HY-Zeolite. The SiO.sub.2-Zeolite support was then impregnated using a solution of ammonium metatungstate hydrate, then dried at 110 C. for 3 hours. The dried mixture was then impregnated using a solution of lanthanum (III) nitrate hexahydrate, then left to once again at 110 C. for 3 hours. The resulted material was then mixed with MgAlCO3 layered double hydroxide followed by calcination under at 550 C. for 2 hours to obtain a second composition containing 7 wt % W, 2 wt % La, 4 wt % Y-zeolite, 9 wt % MgAl oxide, and balancing SiO2, wherein the weight percentages are based on the total weight of the second composition.

[0072] The first composition and the second composition were physically mixed 1:1 by weight to obtain Example 4 catalyst.

[0073] Each catalyst as prepared above was packed in a q tube micro reactor and pretreated with hydrogen at approximately 600 C. for half an hour before contacted with propane at approximately 500 C., 0.05-0.1 bar gauge, and WHSV of approximately 0.1-0.2 hr-.sup.1. The results measured at time on stream for approximately 60 hours and 100 hours are shown in the Table 1 below.

TABLE-US-00001 TABLE 1 Result Selectivity (% wt) C3H8 Conversion (% wt) Total Olefins CH4 C2H4 C3H6 C4H8 60 h 100 h 60 h 100 h 60 h 100 h 60 h 100 h 60 h 100 h 60 h 100 h Example 1 19.64 7.25 74.42 83.78 8.44 5.47 2.60 6.58 59.04 60.76 12.78 16.44 Example 2 15.994 7.510 85.703 92.367 2.688 1.838 3.394 8.298 71.330 70.128 10.978 13.941 Example 3 17.006 11.950 87.079 91.335 1.714 1.183 3.001 5.663 72.442 71.039 11.635 14.632 Example 4 17.227 10.957 80.998 89.495 5.855 3.949 2.826 4.285 65.955 73.758 12.216 11.451

[0074] As be seen from the above table, for the inventive hydrocarbon conversion process, the total olefins selectivity is significantly increased, while methane production is decreased. The high total olefins selectivity also shows that (re)hydrogenation of olefins obtained is low.

[0075] The features disclosed in the foregoing description and the claims may, both separately and in any combination thereof, be material for realizing the invention in diverse forms thereof.