Hydrocarbon conversion catalyst

Abstract

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

Claims

1. A hydrocarbon conversion catalyst, comprising: a first composition comprising a dehydrogenation active metal on a solid support selected from the group consisting of aluminum oxide, silicon dioxide, zirconium dioxide, titanium dioxide, magnesium oxide, calcium oxide, and mixtures thereof; and a second composition comprising a transition metal and a doping agent on an inorganic support, wherein the doping agent is selected from the group consisting of zinc, gallium, indium, lanthanum, and mixtures thereof, wherein the dehydrogenation active metal is selected from the group consisting of platinum, palladium, iridium, chromium, and mixtures thereof; and the inorganic support is silicon dioxide or a mixture of silicon dioxide and a zeolite, wherein the transition metal is selected from the group consisting of molybdenum, tungsten, rhenium, and mixtures thereof.

2. The hydrocarbon conversion catalyst according to claim 1, wherein the first composition further comprises an additional active metal selected from the group consisting of potassium, tin, lanthanum, indium, yttrium, ytterbium, rhenium, and mixtures thereof.

3. The hydrocarbon conversion catalyst according to claim 1, wherein the first composition comprises 0.01 to 25 wt % of the dehydrogenation active metal, based on the total weight of the first composition.

4. The hydrocarbon conversion catalyst according to claim 2, wherein the first composition comprises 0.005 to 2 wt % of the additional active metal, based on the total weight of the first composition.

5. The hydrocarbon conversion catalyst according to claim 1, wherein the zeolite is selected from the group consisting of ZSM-5, X-zeolite, Y-zeolite, beta-zeolite, MCM-22, ferrierite, and mixtures thereof.

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

7. The hydrocarbon conversion catalyst according to claim 1, wherein the second composition comprises 1 to 15 wt % of the transition metal, based on the total weight of the second composition.

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

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

10. The hydrocarbon conversion catalyst according to claim 1, wherein weight ratio of the first composition to the second composition is from 1:10 to 10:1.

Description

EXPERIMENTAL RESULTS

(1) In the examples section below, the conversion of propane into olefins, preferably ethylene, propylene, and butene, has been investigated using hydrocarbon conversion catalysts according to the present invention and a comparative catalyst.

Example 1 (Comparative)

(2) 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 are based on the total weight of the first composition.

(3) 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 Mg—Al—CO3 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 % Mg—Al oxide, and balancing SiO2, wherein the weight percentages are based on the total weight of the second composition.

(4) The first composition and the second composition were physically mixed 1:1 by weight to obtain Example 1 catalyst.

Example 2

(5) A first composition is prepared the same way as described in Example 1.

(6) 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 Mg—Al—CO3 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 % Mg—Al oxide, and balancing SiO2, wherein the weight percentages are based on the total weight of the second composition.

(7) The first composition and the second composition were physically mixed 1:1 by weight to obtain Example 2 catalyst.

Example 3

(8) A first composition is prepared the same way as described in Example 1.

(9) 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 Mg—Al—CO3 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 % Mg—Al oxide, and balancing SiO2, wherein the weight percentages are based on the total weight of the second composition.

(10) The first composition and the second composition were physically mixed 1:1 by weight to obtain Example 3 catalyst.

Example 4

(11) A first composition is prepared the same way as described in Example 1.

(12) 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 lanthanum (III) nitrate hexahydrate, then left to dry once again at 110° C. for 3 hours. The resulted material was then mixed with Mg—Al—CO3 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 % La, 4 wt % Y-zeolite, 9 wt % Mg—Al oxide, and balancing SiO2, wherein the weight percentages are based on the total weight of the second composition.

(13) The first composition and the second composition were physically mixed 1:1 by weight to obtain Example 4 catalyst.

(14) Each catalyst as prepared above was packed in a quartz 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.

(15) TABLE-US-00001 TABLE 1 Result C3H8 Conversion Selectivity (% wt) (% 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

(16) As can be seen from the above table, for the inventive hydrocarbon conversion catalyst, the total olefins selectivity is significantly increased, while methane production is decreased. The increased total olefins selectivity shows that (re)hydrogenation of olefins obtained is lower. The decreased of methane production shows that the effect of hydrogenolysis was suppressed.

(17) 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.