Ultra-stable heavy hydrocarbon hydroprocessing catalyst and methods of making and use thereof

Abstract

An ultra-stable catalyst composition for hydroprocessing hydrocarbon feedstocks and a method of making and use of the ultra-stable catalyst composition. The catalyst composition of the invention comprises a calcined mixture made by calcining a formed particle of a mixture comprising an inorganic oxide material, molybdenum trioxide, and a nickel compound; wherein the calcined mixture is further overlaid with a cobalt component and a molybdenum component to thereby provide the catalyst composition.

Claims

1. A catalyst comprising: (a) a calcined particle comprising an inorganic oxide material and underbedded metals, wherein the underbedded metals comprise molybdenum and nickel; and (b) an overlayer on top of the calcined particle, the overlayer comprising cobalt and molybdenum, and absent a nickel concentration in the form of a nickel overlayer.

2. The catalyst according to claim 1, wherein the calcined particle further comprises a phosphorus compound.

3. The catalyst according to claim 1, wherein the catalyst has a phosphorous content ranging from 0.5 wt. % to 4 wt. %, by weight of the calcined catalyst particle, and wherein the calcined particle has a phosphorous content ranging from 0.05 wt. % to 2 wt. %, by weight of the calcined particle.

4. The catalyst according to claim 3, wherein the overlayer further comprises a phosphorus component.

5. The catalyst according to claim 4, wherein the catalyst has a phosphorous content ranging from 1 wt. % to 3 wt. %, and wherein the calcined particle has a phosphorous content ranging from 0.2 wt. % to 1 wt. %.

6. The catalyst according to claim 1, wherein a molybdenum content of the calcined particle is in the range of from 2 wt. % to 10 wt. % of the total weight of the calcined particle, and a nickel content of the calcined particle is in the range of from about 0.5 wt. % to about 4 wt. % of the total weight of said calcined particle.

7. The catalyst according to claim 6, wherein the molybdenum content of the catalyst is in the range of from 8 wt. % to 18 wt. % of the total weight of the catalyst, and wherein the cobalt content of the catalyst is in the range of from 0.5 to 6 wt. % of the total weight of the catalyst.

8. The catalyst according to claim 7, wherein the catalyst has an absence of a concentration of underbedded cobalt.

9. The catalyst according to claim 8, wherein the catalyst has an absence of a concentration of nickel that is in the form of a nickel overlayer.

10. The catalyst according to claim 1, wherein the calcined particle is made by calcining a particle formed of a mixture comprising an inorganic oxide, a molybdenum trioxide, and a nickel compound.

11. The catalyst according to claim 10, wherein the mixture further comprises phosphorus as both underbedded phosphorus and an overlayer of phosphorus.

12. The catalyst according to claim 11, wherein the catalyst has a phosphorous content ranging from 0.5 wt. % to 4 wt. %, by weight of the calcined catalyst particle, and wherein the calcined particle has a phosphorous content ranging from 0.05 wt. % to 2 wt. %, by weight of the calcined particle.

13. The catalyst according to claim 1, wherein less than 5% of a total pore volume of the catalyst has a pore diameter of greater than 1,000 angstroms.

14. The catalyst according to claim 1, wherein at least 40% of a total pore volume of the catalyst has a pore in the range of from 100 angstroms to 150 angstroms.

Description

EXAMPLE 1

(1) This Example 1 describes the preparation and composition of one exemplary catalyst composition according to the invention.

(2) Catalyst A

(3) Catalyst A was prepared by first combining 2400 parts by weight alumina, 291.61 parts by weight nickel nitrate (Ni(NO.sub.3).sub.2) dissolved in 100.85 parts by weight deionized water, and 900 parts by weight crushed Ni/Mo/P hydrotreating catalyst and 284.5 parts of MoO.sub.3 within a Muller mixer along with 130 parts by weight 69.9% concentrated nitric acid and 30 grams of a commercial extrusion aid. A total of 2840.63 parts by weight of water was added to these components during the mixing. The components were mixed for approximately 45 minutes. The mixture had a pH of 4.23 and an LOI of 55.46 weight percent. The mixture was then extruded using 1.3 mm trilobe dies to form 1.3 trilobe extrudate particles. The extrudate particles were then dried in air for a period of several hours at a temperature of 100° C.

(4) Aliquot portions of the dried extrudate particles were calcined in air each for a period of two hours at a temperature of 766° C. (1410° F.). The final calcined mixture contained 2.2 weight percent nickel metal (2.8 wt. % as NiO), and 7.9% molybdenum metal (11.9 wt. % as MoO.sub.3) and 83.6 weight percent of alumina containing and 1.1% of phosphorus pentaoxide.

(5) The following Table 1 presents certain properties of the calcined extrudate. As may be seen from the pore properties presented in Table 1, the percentage of the total pore volume contained in the micropores having a pore diameter of greater than 1000 Angstroms is less than 5% percent and a pore diameter of from 100-150 A is at least 40%.

(6) TABLE-US-00001 TABLE 1 Properties of Calcined Catalyst A Properties MoO.sub.3 11.85 NiO  2.75 Hg Pore Size Dist. (Angs)  <70 5.1% 70-350 92.3%   >350 2.6% >1000 0.2% >5000 .sup. 0% Total Pore Volume, cc/g 0.60%  Medium Pore Diameter, Å  90%

(7) Catalyst B

(8) An impregration solution was prepared by first combining 6.98 parts of 85.8% phosphoric acid and 16.5 parts of MoO.sub.3 in 92 ml of DI water and heated the solution to 82° C. Added 4.52 parts of Co(OH).sub.2 slowly to control exotherm and heated the mixture to 100° C. Added 4.37 parts of citric acid. Cooked for 30 minutes to clear. Adjusted volume based on final catalyst pore volume—solution pH was 2.64.

(9) Impregnated 100 parts of Catalyst A with the final solution. Aged impregnated catalyst for two hours at room temperature with occasional shaking. Dried the impregnated catalyst for two hours at 135° C. and calcined in air for a period of two hours at a temperature of 482° C. (900° F.). The final calcined mixture contained 1.9 weight percent nickel metal (2.4 wt. % as NiO), 2.3 weight percent of cobalt (2.9 wt % as CoO) and 14.1 weight percent molybdenum metal (21.1 wt. % as MoO.sub.3) and 69.3 weight percent of alumina and 4.27% of phosphorus pentaoxide.

(10) The following Table 1 presents certain properties of the calcined extrudate. As may be seen from the pore properties presented in Table 1, the percentage of the total pore volume contained in the micropores having a pore diameter of greater than 1000 Angstroms was higher than 10% percent.

(11) TABLE-US-00002 TABLE 2 Properties of Calcined Catalyst B Calcination Temperature Properties 482° C. (900° F.) MoO.sub.3 21.1 NiO 2.4 CoO 2.9  <70 2.8% 70-350 2.3%  >350 2.3% >1000 0.2 >5000 0 Total Pore Volume, cc/g 0.45 Medium Pore Diameter, Å 99

EXAMPLE 2

(12) This Example 2 describes one of the methods used in testing the catalysts described in Example 1. This method provided for the processing of a feedstock having a significant sulfur concentration to yield a product having specified sulfur concentration. The reactor temperature was operated at a temperature of 700° F.

(13) 16.7 cc/7.83 g of a commercial HDM catalyst obtained from Criterion Catalyst company (RM-5030 1.3 TL) was first intimately mixed with 16.7 cc of silicon carbide of 20 mesh size. Separately, 33.7 cc/26.1 g of Catalyst A were mixed with 33.7 cc of silicon carbide of 20 mesh size. 130 g of 20 mesh silicon carbide was placed into a 1.5875 cm (⅝ inch) ID by 127 cm (50 inch) stainless steel tube reactor, with the catalyst. The tube reactor was equipped with thermocouples placed in a 0.635 cm (¼ inch) thermo-well inserted concentrically into the catalyst bed, and the reactor tube was held within a 132 cm (52 inch) long 5-zone furnace with each of the zones being separately controlled based on a signal from a thermocouple.

(14) The first mixture of commercial HDM catalyst and silicon carbide was poured into reactor with gentle tapping, followed by Catalyst A and silicon carbide mixture. The reactor was tapped several times and a plug of glass wool inserted followed by 130 g of Sic and another glass plug.

(15) The catalyst bed was activated by feeding at ambient pressure a gas mixture of 5 vol. % H2S and 95 vol. % H.sub.2 to the reactor at a rate of 1.5 LHSV while incrementally increasing the reactor temperature at a rate of 100° F./hr up to 400° F. The catalyst bed was maintained at a temperature of 400° F. for two hours and then the temperature was incrementally increased at a rate of 100° F./hr to a temperature of 600° F., where it was held for one hour followed again by an incremental increase in the temperature at a rate of 75° F./hr up to a temperature of 700° F., where it was held for two hours before cooling the catalyst bed temperature down to the ambient temperature. The catalyst bed was then pressured with pure hydrogen at 1000 psig, and the temperature of the catalyst bed was incrementally increased at a rate of 100° F./hr to 400° F. The reactor was then charged with feedstock while the temperature of the reactor was held at 400° F. for one hour. The catalyst bed temperature was then incrementally increased at a rate of 50° F./hr up 700° F., from which point the run was started. Catalyst B was also loaded and sulfided similarly.

(16) The feedstock charged to the reactor was a Middle Eastern origin long residue. The distillation properties of the feedstock as determined by ASTM Method D7169 are presented in Table 2. Table 3 presents certain other properties of the feedstock.

(17) TABLE-US-00003 TABLE 2 Distillation of Feedstock Temp. ° F. Wt. % IBP 522.0 721.0 10.0 806.0 20.0 871.0 30.0 932.0 40.0 999.0 50.0 1074.0 60.0 1159.0 70.0 1260.0 80.0 0.0 90.0 FBP 1351.0

(18) TABLE-US-00004 TABLE 3 Other properties of the feedstock H (wt %) 11.010 C (wt %) 84.070 O (wt %) 0.085 N (wt %) 0.260 S (wt %) 4.575 MCR 12.10 1000F+ 49.10 C7 asph 5.50 Density 60° F. 0.9819 Ni (ppm) 20.6 V (ppm) 70.0 M (ppm) 90.6 BN (ppm) 734 P-Value 2.80 Viscosity 6067.0 C5-asph 12.10

(19) The feedstock was charged to the reactor along with hydrogen gas. The reactor was maintained at a pressure of 1900 psig and the feedstock was charged to the reactor at a rate so as to provide a liquid hourly space velocity (LHSV) of 1.00 hr-1 and the hydrogen was charged at a rate of 4,000 SCF/bbl. The temperature of the reactor was set at 371° C. (700° F.).

(20) This method provided for the processing of a feedstock having significant sulfur and pitch contents to yield a product having reduced sulfur and pitch contents and product liquid that is stable. The reactor temperature was kept constant in conducting these reactions and the sulfur content, the pitch content and the product liquid quality were monitored.

(21) Presented in FIG. 1 are plots temperature required to achieve 89% removal of sulfur from feed (0.50 wt. %) sulfur in product liquid (the estimated linear using product sulfur content, 2.sup.nd order reaction rate constant and an activation energy for sulfur removal of 33.4 Kcal/mol).

(22) As may be seen from the FIG. 1, the HDS activity of the inventive catalyst is significantly better than that of the comparison catalyst in that the reactor temperature required to achieve the 89% conversion of sulfur with the use of the inventive catalyst is as much as 20-30° F. lower than with the use of the comparison catalyst. Also, it is further unexpected that the stability of the inventive catalyst, which is indicated by the rate of decline in the HDS activity of the catalyst, is comparable to that of the comparison catalyst. This is in spite of the of molybdenum content in the inventive catalyst.