PROCESS FOR PREPARING HYDROCRACKING CATALYST

Abstract

The invention relates to a process for preparing a hydrocracking catalyst, comprising (i) contacting a shaped body comprising a zeolite and a binder with an aqueous solution of a hydrogenation metal compound which is a complex or a salt of a hydrogenation metal to deposit the hydrogenation metal onto the shaped body, wherein the aqueous solution comprises an ammonium salt and (ii) calcining the shaped body obtained by step (i).

Claims

1. A process for preparing a hydrocracking catalyst, comprising: (i) contacting a shaped body comprising a zeolite and a binder with an aqueous solution of a hydrogenation metal compound which is a complex or a salt of a hydrogenation metal to deposit the hydrogenation metal onto the shaped body, wherein the aqueous solution comprises an ammonium salt; and (ii) calcining the shaped body obtained by step (i).

2. The process according to claim 1, wherein the hydrogenation metal is at least one element selected from Group 10 of the periodic table of elements or rhodium or iridium.

3. The process according to claim 1, wherein the hydrogenation metal compound is a metal amine complex.

4. The process according to claim 1, wherein the hydrogenation metal compound is free of chlorine.

5. The process according to claim 1, wherein the ammonium salt is selected from the group consisting of NH.sub.4Cl, NH.sub.4NO.sub.3, (NH.sub.4).sub.2CO.sub.3 and NH.sub.4HCO.sub.3.

6. The process according to claim 1, wherein the ammonium salt is free of chlorine.

7. The process according to claim 1, wherein the zeolite is ZSM 5.

8. The process according to claim 1, wherein the zeolite has a silica (SiO.sub.2) to alumina (Al.sub.2O.sub.3) molar ratio of 25-75.

9. The process according to claim 1, wherein the amount of the hydrogenation metal is 0.010-0.30 wt % with respect to the total catalyst.

10. The process according to claim 1, wherein the amount of the hydrogenation metal is 0.015-0.095 wt % with respect to the total catalyst.

11. The process according to claim 1, wherein the shaped body is an extrudate having an average diameter of 0.1-3 mm.

12. The hydrocracking catalyst obtained by the process according to claim 1.

13. A process for hydrocracking a feed stream comprising hydrocarbons by contacting the feed stream in the presence of hydrogen with the catalyst according to claim 12, and forming a hydrocracking product stream.

14. The process according to claim 13, wherein contacting the feed stream comprises contacting the feed stream under process conditions including a temperature of 400-580 C., a pressure of 300-5000 kPa gauge and a Weight Hourly Space Velocity of 3-30 h.sup.1 to produce the hydrocracking product stream comprising BTX; and separating the BTX from the hydrocracking product stream.

15. The process according to claim 3, wherein the hydrogenation metal compound is selected from the group consisting of (NH.sub.3).sub.4Pt(NO.sub.3).sub.2, (NH.sub.3).sub.4Pt(OH).sub.2 and (NH.sub.3).sub.4PtCl.sub.2.

16. The process according to claim 1, wherein the hydrogenation metal compound is selected from the group consisting of (NH.sub.3).sub.4Pt(NO.sub.3).sub.2 and (NH.sub.3).sub.4Pt(OH).sub.2.

17. The process according to claim 1, wherein the ammonium salt is (NH.sub.4).sub.2CO.sub.3.

18. The process according to claim 1, wherein the ammonium salt selected from the group consisting of NH.sub.4NO.sub.3, (NH.sub.4).sub.2CO.sub.3 and NH.sub.4HCO.sub.3.

19. The process according to claim 1, wherein the hydrogenation metal compound is selected from the group consisting of (NH.sub.3).sub.4Pt(NO.sub.3).sub.2 and (NH.sub.3).sub.4Pt(OH).sub.2; wherein the amount of the hydrogenation metal is 0.015-0.095 wt %, with respect to the total catalyst; and wherein the ammonium salt selected from the group consisting of NH.sub.4NO.sub.3, (NH.sub.4).sub.2CO.sub.3 and NH.sub.4HCO.sub.3.

20. The process according to claim 19, wherein the amount of the hydrogenation metal is 0.035-0.080 wt %, with respect to the total catalyst; and wherein the zeolite has a silica (SiO.sub.2) to alumina (Al.sub.2O.sub.3) molar ratio of 35-60.

Description

EXAMPLE 1

[0168] Catalyst A, weight 0.10 g

[0169] Catalyst pretreatment: (a) drying: under 40 sccm H.sub.2 at 50 psig at 130 C. for 2 h; (b) subsequent H.sub.2S treatment: 40 sccm of H.sub.2 (with 50 ppm of H.sub.2S) at 50 psig at 350 C. for 30 min

[0170] Hydrocarbon feed composition: 70.0 wt % benzene, 15.0 wt % 3-methylpentane, 15.0 wt % methylcyclopentane

[0171] Hydrocarbon feed rate varied from 10.3 to 20.6 l/min to run at WHSV 4.86 to 9.72 h.sup.1. H.sub.2 (+H.sub.2S) rate: varied to maintain H.sub.2 to HC molar ratio of 4 to 1, and H.sub.2S content 50 ppm based on total feed

[0172] Catalyst bed temperature 470 C., pressure 200 psig

EXAMPLE 2

[0173] Catalyst E, weight 0.10 g

[0174] Catalyst pretreatment: same as described in example 1.

[0175] Hydrocarbon feed composition and rate: same as described in example 1.

[0176] Hydrocarbon feed rate varied from 20.6 to 30.9 l/min to run at WHSV 10.0 to 15.0 h.sup.1.

[0177] H.sub.2 (+H.sub.2S) rate: varied as described in example 1.

[0178] Catalyst bed temperature 470 C., pressure 200 psig.

EXAMPLE 3

[0179] Catalyst H, weight 0.10 g

[0180] Catalyst pretreatment: same as described in example 1.

[0181] Hydrocarbon feed composition and rate: same as described in example 1.

[0182] Hydrocarbon feed rate varied from 20.6 to 24.7 l/min to run at WHSV 10.0 to 11.5 h.sup.1. H.sub.2 (+H.sub.2S) rate: varied as described in example 1.

[0183] Catalyst bed temperature 470 C., pressure 200 psig.

EXAMPLE 4

[0184] Catalyst I, weight 0.10 g

[0185] Catalyst pretreatment: same as described in example 1.

[0186] Hydrocarbon feed composition and rate: same as described in example 1.

[0187] Hydrocarbon feed rate varied from 20.6 to 22.7 l/min to run at WHSV 10.0 to 11.0 h.sup.1.

[0188] H.sub.2 (+H.sub.2S) rate: varied as described in example 1.

[0189] Catalyst bed temperature 470 C., pressure 200 psig.

EXAMPLE 5

[0190] Catalyst K, weight 0.10 g

[0191] Catalyst pretreatment: same as described in example 1.

[0192] Hydrocarbon feed composition and rate: same as described in example 1.

[0193] Hydrocarbon feed rate varied from 20.6 to 30.9 l/min to run at WHSV 10.0 to 14.6 h.sup.1.

[0194] H.sub.2 (+H.sub.2S) rate: varied as described in example 1.

[0195] Catalyst bed temperature 470 C., pressure 200 psig.

EXAMPLE 6

[0196] Catalyst L, weight 0.10 g

[0197] Catalyst pretreatment: same as described in example 1.

[0198] Hydrocarbon feed composition and rate: same as described in example 1.

[0199] Hydrocarbon feed rate varied from 20.6 to 28.8 l/min to run at WHSV 10.0 to 14.0 h.sup.1.

[0200] H.sub.2 (+H.sub.2S) rate: varied as described in example 1.

[0201] Catalyst bed temperature 470 C., pressure 200 psig.

EXAMPLE 7

[0202] Catalyst M, weight 0.10 g

[0203] Catalyst pretreatment: same as described in example 1.

[0204] Hydrocarbon feed composition and rate: same as described in example 1.

[0205] Hydrocarbon feed rate varied from 18.5 to 20.6 l/min to run at WHSV 9.2 to 10.0 h.sup.1.

[0206] H.sub.2 (+H.sub.2S) rate: varied as described in example 1.

[0207] Catalyst bed temperature 470 C., pressure 200 psig.

EXAMPLE 8

[0208] Catalyst N, weight 0.10 g

[0209] Catalyst pretreatment: same as described in example 1.

[0210] Hydrocarbon feed composition and rate: same as described in example 1.

[0211] Hydrocarbon feed rate varied from 20.6 to 22.7 l/min to run at WHSV 10.0 to 11.0 h.sup.1.

[0212] H.sub.2 (+H.sub.2S) rate: varied as described in example 1.

[0213] Catalyst bed temperature 470 C., pressure 200 psig.

TABLE-US-00007 TABLE 8 Hydrocracking performance of various catalysts made using (NH.sub.3).sub.4Pt(NO.sub.3).sub.2 as the Pt source, with and without additive Shell Pt, Ex Catalyst Additive [(NH.sub.4).sup.+]/Pt Formation wt % WHSV/h CH.sub.4 Lights Benzene Aromatics.sup.1 1 A None 0 Shell 0.07 Low formed activity.sup.2 2 E NH.sub.4Cl 150 No 0.07 12.96 1.32 27.78 67.29 72.06 3 H NH.sub.4NO.sub.3 150 No 0.08 10.28 1.45 32.01 64.40 67.84 4 I NH.sub.4NO.sub.3 1500 No 0.08 10.57 1.30 28.22 67.13 71.65 5 K (NH.sub.4).sub.2CO.sub.3 1500 No 0.08 13.61 1.33 28.66 65.92 71.20 6 L (NH.sub.4).sub.2CO.sub.3 3000 No 0.07 12.55 1.34 27.31 67.17 72.53 7 M NH.sub.4HCO.sub.3 150 No 0.07 9.70 1.45 31.56 63.92 68.31 8 N NH.sub.4HCO.sub.3 1500 No 0.08 10.01.sup.a 1.39 29.82 66.26 70.05 .sup.1Aromatics = total aromatics .sup.2benzene purity of 99.82% could not be reached at WHSV 4.9-9.7/h suggesting low catalyst activity compared to the other catalysts listed in the table. .sup.aat benzene purity 99.83%

[0214] It can be understood that the catalyst(s) in which the Pt distribution was non-uniform or formed a shell did not reach a benzene purity of 99.82 wt % in the effluent even at about 50% lower WHSV (example 1) compared to the catalysts in which Pt distribution was uniform (examples 2-8). One can conclude that catalysts with uniform Pt distribution, that is, with no shell formation showed high activity (WHSV 9.7 to 13.6/h) with benzene and total aromatics yields 63.9-67.3% and 67.8-72.5%, respectively.