HYDROPROCESSING CATALYST PREPARED WITH WASTE CATALYST FINES AND ITS USE

Abstract

A hydroprocessing catalyst composition that comprises a shaped support that is formed from a mixture of inorganic oxide powder and catalyst fines and wherein the shaped support has incorporated therein at least one metal component, a chelating agent and a polar additive. The hydroprocessing catalyst composition is prepared by incorporating into the shaped support a metal component, a chelating agent and a polar additive. The hydroprocessing catalyst composition has particular application in the catalytic hydroprocessing of petroleum derived feedstocks.

Claims

1. A hydroprocessing process, comprising: contacting under hydroprocessing reaction conditions a hydrocarbon feedstock with a catalyst composition, comprising a shaped support formed from a mixture comprising an inorganic oxide powder and catalyst fines in an amount in the range upwardly to about 50 wt %; at least one metal component incorporated into said shaped support; a chelating agent; and a polar additive; wherein the fraction of the total pore volume of said shaped support that is contained in macropores exceeds 10%.

2. A hydroprocessing process as recited in claim 1, wherein said chelating agent is selected from the group of compounds consisting of aminocarboxylic acids, polyamines, aminoalcohols, oximes, and polyethyleneimines.

3. A hydroprocessing process as recited in claim 2, wherein said polar additive is a heterocompound having polarity and a dipole moment of at least 0.45.

4. A hydroprocessing process as recited in claim 3, wherein said at least one metal component comprises a Group 9 or Group 10 metal component selected from the group consisting of cobalt and nickel present in an amount in the range of from 0.5 wt. % to 20 wt. %, and a Group 6 metal component selected from the group consisting of molybdenum and tungsten present in an amount in the range of from 5 wt. % to 50 wt. %, wherein the weight percents are based on the weight of the dry shaped support with the metal component as the element regardless of its actual form.

5. A hydroprocessing process as recited in claim 4, wherein said inorganic oxide powder of said shaped support is a porous refractory oxide selected from the group of refractory oxides consisting of silica, alumina, titania, zirconia, silica-alumina, silica-titania, silica-zirconia, titania-alumina, zirconia-alumina, silica-titania and combinations of two or more thereof; and wherein said shaped support has a surface area (as determined by the BET method) in the range of from 50 m.sup.2/g to 450 m.sup.2/g, a mean pore diameter in the range of from 50 to 200 angstroms (), and a total pore volume exceeding 0.55 cc/g.

6. A hydroprocessing process as recited in claim 5, wherein at least 75% of the available pore volume of said shaped support is filled with said polar additive.

7. A process, comprising: contacting under hydroprocessing reaction conditions a hydrocarbon feedstock a composition made by the method comprising: forming a shaped support comprising an inorganic oxide powder and catalyst fines, wherein said catalyst fines are present in said shaped support in an amount in the range up to 50 wt % of said shaped support, wherein the fraction of the total pore volume of the shaped support that is contained in macropores exceeds 10%, and wherein said shaped support is dried and calcined; incorporating a chelating agent and a metal-containing solution into said shaped support to provide a chelant treated metal-incorporated support; drying said chelant treated metal-incorporated support so as to provide a dried chelant treated metal-incorporated support having a volatiles content in the range of from 1 to 20 wt % LOI thereby creating an available pore volume; and incorporating a polar additive into said dried chelant treated metal-incorporated support in an amount such that at least 75% of the available pore volume of said dried chelant treated metal-incorporated support is filled with said polar additive, to thereby provide an additive impregnated composition.

Description

EXAMPLE 1

[0124] This Example describes the preparation of a comparative support made from powdered alumina without the addition of catalyst fines and the preparation of a support made using metal bearing catalyst fines in addition to powdered alumina. The support containing catalyst fines was used in the preparation of the inventive catalyst composition of Example 3. This Example further presents selected physical property data for each supports.

[0125] The comparative support was made by mixing alumina, water and nitric acid to form a mixture that was extruded into 1.3 mm Trilobe extrudates. The shaped support extrudates were dried and calcined using standard drying and calcination techniques so as to provide an alumina carrier for loading the active metals and additive components of the compositions. The properties of the shaped alumina support are presented in Table 2 below.

TABLE-US-00002 TABLE 2 Properties of Shaped Support without incorporation of metal bearing fines Property Value Shape 1.3 mm Trilobe N2 Surface area (m2/g) 300 Mean pore diameter by vol. (Ang.) 91 Pore volume greater than 350 Ang. (%) <5 Water pore volume (cc/g) 0.88

[0126] The support containing catalyst fines was made in a similar manner by mixing alumina powder, metal bearing catalyst fines, water and nitric acid to form a mixture that was extruded into 1.3 mm Trilobe extrudate. The amount of fines taken for the preparation was chosen to be 30% by weight of alumina from the fines, 70% of total alumina content by weight being from the fresh alumina powder.

TABLE-US-00003 TABLE 3 Properties of Shaped Support with incorporation of 30% regenerated catalyst fines Property Value Shape 1.3 mm Trilobe N2 Surface area (m2/g) 320 Mean pore diameter by vol. (Ang.) 89 Pore volume greater than 350 Ang. (%) 20.2 Water pore volume (cc/g) 0.883 Ni, wt % 0.8 Mo, wt % 4.0 P, wt % 0.8

[0127] The cumulative pore size distribution for each of the two supports was measured by mercury porosimetry with the results presented in FIG. 1.

[0128] As may be observed in the plots of FIG. 1, the comparative support has a pore structure such that less than 5% of its total pore volume is contained in the macropores (i.e., pores having a pore diameter greater than 350 angstroms) of the support, but, on the other hand, the support containing the catalyst fines has a pore structure such that at least 20% of its total pore volume is contained in the macropores. This demonstrates the effect that the use of catalyst fines in the preparation of a support has on the final pore structure of the support. As mentioned earlier herein, an increased amount of macropores in a catalyst can, for certain applications, cause loss in catalytic activity.

EXAMPLE 2

[0129] This Example describes the preparation of comparative Composition A using the comparative support described in Example 1 with properties outlined in Table 2.

[0130] 200 grams of the dry support was taken for the impregnation with the following described impregnation solution. The impregnation solution was prepared as follows: 59.07 g (NH.sub.4).sub.2Mo.sub.2O.sub.7, 16.57 g MoO.sub.3 and 47.83 ml DI H.sub.2O were combined in a glass beaker with stirring at ambient temperature. 2.85 g MEA (monoethanolamine) were added to the mixture below surface to control exotherm. The mixture was heated to 140 F to dissolve solids, and cooled down to ambient at pH=5.29 to provide the Solution 1.

[0131] Separately, 30.59 g of nickel nitrate Ni(NO.sub.3).sub.26H.sub.2O were combined with 8.86 g of nickel carbonate NiCO.sub.3 in 29.2 ml DI H.sub.2O. 23.83 g of phosphoric acid H.sub.3PO.sub.4 (85.9%) was slowly added to control foaming. After forming a clear Solution 2 at ambient temperature the pH was 0.19.

[0132] Solution 2 was then added to Solution 1 with stirring. The resulting mixture was topped with DI H.sub.2O to give a total solution volume of 176 ml which equals to the total water pore volume of 200 g support taken for the synthesis. The pH of the final solution prior to impregnation was 2.82.

[0133] The impregnation solution was added at once to the support, and the impregnates were aged with occasional shaking for a few hours.

[0134] The impregnates were dried at 212 F. (100 C.) for 4 hours and finally calcined at 900 F. (482 C.) for 2 hours to yield comparative Composition A with the following target metals contents: 15.0% Mo, 3.5% Ni, 2.2% P (dry basis).

EXAMPLE 3

[0135] This Example describes the preparation of Composition B, which is one embodiment of the inventive composition, using the support containing 30% regenerated catalyst fines of Example 1 that is impregnated with hydrogenation metal components and a chelating agent and then dried and filled with a polar additive.

[0136] Composition B was impregnated with a solution comprising the chelating agent diethylenetriaminepentaacetic acid (DTPA) and metals. This solution was prepared as follows: 56.44 g MoO.sub.3 (66.5% Mo), 22.73 g NiCO.sub.3 (42.73% Ni) and 67 ml DI H.sub.2O were combined in a glass beaker with stirring at ambient temperature. The mixture was heated to about 195 F. (91 C.) with steering until a clear solution was obtained. The solution was allowed to cool down to about 140 F. (60 C.) at which time 12.72 g diethylenetriaminepentaacetic acid (DTPA, 99% concentration, BASF, Trilon C Powder) were added. After cooling the solution to ambient temperature, and it was topped DI water to a volume to 143.1 ml. A final clear solution was obtained.

[0137] The impregnation solution was added at once to 160.15 g of the support, containing catalyst fines (Example 1, Table 2). The impregnates were aged with occasional shaking for a few hours, and then dried in air at 300 F. (149 C.) for 3 hours (but not calcined) in order to eliminate excess moisture and reduce the volatiles content thereof to a target LOI and to free up pore volume that could subsequently be filled with a polar additive. Catalyst intermediate of the Composition B was thus obtained. Metals contents added from the impregnation solution (dry fresh metals basis) were 15.36% Mo and 3.98% Ni as well as 2.76% P.

[0138] The dried catalyst intermediate was then filled by pore volume impregnation with the polar additive dimethylformamide (DMF) to at least a 90% pore volume fill to give the inventive Composition B (additive impregnated composition).

EXAMPLE 4

[0139] The example describes inventive Composition C that was obtained by pore volume impregnation of the intermediate Composition B (described in Example 3) with a blend of polar additives comprising 50% mixture by volume DMF and 50% hexadecylamine.

EXAMPLE 5

[0140] This Example describes the procedure for testing the catalytic performance of the compositions of Examples 2-4, and it presents the performance results from their use in the hydrotreating of a vacuum gas oil feedstock (activity testing).

[0141] Trickle flow micro-reactors were used to test the hydrodesulfurization (HDS) and hydrodenitrogenation (HDN) activities of the catalyst Compositions A, B, and C.

[0142] A 50 cc volume, based on compacted bulk density of whole pellets, of each composition was used in the testing. The reactors were packed with extrudates of each composition, which were diluted with 80-60 mesh SiC in the volumetric composition-to-diluent ratio of 1:1. The compositions were conditioned and sulfided using a delayed-feed introduction procedure whereby the composition was first heated up and conditioned by contacting it with pure hydrogen at the operating pressure and at a temperature in the range of from 149 C. (300 F.) to 204 C. (400 F.) for a time period of about 12 hours. Following this hydrogen treatment, the composition was sulfided using a liquid hydrocarbon of a gas oil boiling in diesel range containing DMDS to provide a sulfur content of 2.5% in the sulfiding feed.

[0143] The activity of the compositions was tested by charging the reactors with a blended feedstock of a VGO (vacuum gas oil) boiling range. The feedstock had a sulfur content of 3.32 wt. %, a nitrogen content of 0.231 wt. %, and it was charged to the reactor, which was operated at a pressure of 1400 psig, at a rate so as to provide a liquid hourly space velocity (LHSV) of 0.75 hr.sup.1. The hydrogen gas rate charged to the reactor was 3500 scf H.sub.2/bbl. The weight average bed temperature (WABT) was normalized for 260 ppm product nitrogen target.

[0144] FIG. 2 presents the results of the testing with activity determined as the WABT required to achieve targeted 260 ppm nitrogen content in the product. It can be observed from the presented plots that the inventive Composition C exhibits a higher activity (a lower WABT for the given HDN level) than inventive Composition B and comparative Composition A. Composition C provided 68 ppm total nitrogen in the product whereas the Composition B showed a 125 ppm total nitrogen in the product that translates into a 5.5 C. (10 F.) temperature advantage of the inventive Composition C filled with a blend of DMF and hexadecylamine over inventive Composition B filled with DMF alone.