A kind of Hydrobon catalyst
The present invention relates to a kind of Hydrobon catalyst that is used for the petroleum distillate unifining process.
Be SO in the control air
XContent, Yan Ge environmental regulation proposes more and more harsher restriction to the sulfur content in the oil product day by day.The hydrodesulfurization technology is to reduce the main means of sulfur content in the oil product, and its technical merit depends on the hydrodesulfurization performance of catalyst system therefor to a great extent.Therefore, although the existing different Hydrobon catalyst of kind on the market, people still expect to develop the more excellent catalyst of performance.
Typical Hydrobon catalyst is with aluminium oxide, and group vib and VIII family metal component constitute, and the most frequently used group vib element is a molybdenum, and VIII family element is a cobalt.
Suitably increasing active component content is one of approach that improves catalyst activity.For being the Hydrobon catalyst of active component with Co-Mo, because the preparation of high concentration maceration extract is very difficult, the method for soaking prepares the high catalyst of efficient property constituent content and can't adopt once altogether.Usually the way that adopts has:
(1) step impregnation method, this method support cobalt salt and molybdenum salt at twice respectively, and all need dry, roasting behind each dipping.Therefore, there is the shortcoming that energy consumption is big, production efficiency is low.
(2) kneading method, United States Patent (USP) 3,894,699,4,124,537 have adopted whole active components and aluminium oxide to mix pinch after, the way of extruded moulding.It has the simple advantage of flow process, but kneading method generates non-active species easily, influences catalyst activity.
(3) the part co-extrusion combines with infusion process, United States Patent (USP) 4,036, and 784 have proposed the method that co-extrusion combines with dipping.Wherein the amount of metal of co-extrusion accounts for the 10-40% of total amount of metal in the final catalyst.Remainder adopts infusion process to support.This patent adopts common Mo-Co-NH
3Maceration extract.When the high metals content catalysts of preparation, still there is the solution instability, cause the catalyst surface irregular colour even, metal disperses unfavorable shortcoming.
The object of the present invention is to provide a kind of Hydrobon catalyst.At the problem that prior art exists, the method that has adopted co-extrusion to combine with dipping, and selected more stable maceration extract for use, and it is even to prepare color, and metal is scattered, active higher catalyst.Enhance productivity simultaneously.
Catalyst of the present invention is by aluminium oxide, and 3~7% (weight) VIII family metal oxide and 15~25% (weight) group vib metal oxide are formed.Wherein 10~40% (weights) of group vib and VIII family metal component are by adding with the form of boehmite co-extrusion, and remaining amount is mixed with stabilizing solution by its metallic salt and citric acid and ammoniacal liquor, supports with infusion process.Catalyst pore volume of the present invention is 0.35~0.50ml/g, and specific area is at 150~300m
2Between/the g.
Preparation of catalysts process of the present invention is:
(1) with the boehmite of crushing screening, VIII family and group vib metal compound powder fully mix, and add peptizing agent and enough water, pinch the paste of extrusion modling but evenly mix.The content of group vib and VIII family metal accounts for the 10-40% (weight) of group vib and VIII family tenor in the finished catalyst in the mixture.
(2) with above-mentioned paste through the banded extruder extrusion modling.Extruding the bar profile can be that equivalent diameter is garden cylindricality or the leafy careless shape of 1.2-1.6mm.Extrudate is 60-150 ℃ of drying.Roasting in air again, sintering temperature are 480 ℃-600 ℃, and the time is 2-5 hour.
(3) adopt infusion process to support remaining group vib and VIII family component.
At first measure the absorptivity of extrudate after the roasting.Determine impregnation concentration according to absorptivity and catalyst composition requirement then, prepare the Co-Mo-citric acid-NH of this concentration
3H
2O solution adopts the hole saturation to flood.
(4) dipping after strip 60-150 ℃ of drying, roasting in air again, sintering temperature is 480 ℃-600 ℃, the time is 2-5 hour.
Can to be aluminium salt such as aluminum sulfate, aluminum nitrate, aluminium chloride, sodium aluminate make after neutralization reaction, aging, washing, drying used boehmite in the catalyst preparation process of the present invention.Its alumina content is 65%-85%.It is after roasting under the roasting condition of the present invention, and can make pore volume is 0.65-1.15ml/g, and specific area is greater than 200m
2γ-Al of/g
2O
3
VIII family element in the catalyst of the present invention is that cobalt, group vib element are molybdenums.
In the catalyst preparation process of the present invention, the VIII compounds of group in the step (1) can be basic cobaltous carbonate, cobalt carbonate or cobalt nitrate: the VIII compounds of group can be ammonium molybdate, molybdic acid or molybdenum oxide.Used group vib compound ammonium molybdate preferably in the step (3), the VIII compounds of group is basic cobaltous carbonate preferably.
Peptizing agent used in the catalyst preparation process of the present invention can be organic acid, as acetic acid, also can be inorganic acid, as nitric acid, hydrochloric acid.Be preferably nitric acid.Its consumption is:
HNO
3/ Al
2O
3(weight)=0.02-0.06.
The dipping of catalyst of the present invention adopts saturated infusion process, and no maceration extract recycles problem.Used Co-Mo-citric acid-NHH
2The compound method of O solution is: take by weighing a certain amount of citric acid, the water dissolving adds a certain amount of basic cobaltous carbonate, boils dissolving under stirring.Be cooled to room temperature, adding 20%-28% (weight) ammonia spirit is an amount of.Under stirring, add a certain amount of ammonium molybdate then, treat its dissolving after, use 20%-28% (weight) ammoniacal liquor to transfer to volume required again.Got final product in constant temperature 2-6 hour at 40 ℃-80 ℃ under the airtight condition.Its concentration is per 100 milliliters and contains MoO
3Be not more than 27g, CoO is not more than 5.5g.Citric acid/Co (mol ratio) 0.7~1.5 wherein.
The concentration of maceration extract is according to the catalyst composition requirement, and the absorptivity of extrudate is determined after co-extrusion amount of metal and the roasting.
Catalyst of the present invention has good hydrodesulfurization effect to distillate under the hydrofinishing condition of routine.
By following embodiments of the invention and comparative example, the characteristics of Preparation of Catalyst of the present invention as can be seen.By estimating the hydrodesulfurization activity of the embodiment of the invention and comparative example catalyst, the hydrodesulfurization effect of catalyst of the present invention as can be seen.
Activity rating feedstock oil is Saudi Arabia's light oil: the vacuum distillate of Saudi Arabia's mixed crude of Saudi Arabia's heavy oil=1: 1 (weight ratio), its character sees Table 1.
The evaluation process conditions are: hydrogen dividing potential drop: 6.5MPa, and reaction temperature: 350 ℃, volume space velocity during liquid: 1.8h-1, hydrogen to oil volume ratio: 600, evaluating apparatus: the 100ml fixed bed, one way is once passed through.Table 1 feedstock oil character
Density (20 ℃), g/cm
1 | 0.9102 |
Boiling range (ASTMD1160), ℃ | |
IBP/10% | 350/386 |
30%/50% | 411/430 |
70%/90% | 460/500 |
EBP | 535 |
Sulphur, W% | 2.38 |
Nitrogen, * 10
-4 | 689 |
Freezing point, ℃ | 25 |
Carbon residue, w% | 0.06 |
Acid number, mgKOH/100ml | 0.33 |
The desulphurizing activated computational methods of catalyst relative volume:
Wherein: when Srp-adopts reference catalyst, generate the sulfur content of oil.
When Sp-adopts sample catalyst, generate the sulfur content of oil.
The sulfur content of Sf-feedstock oil.
Embodiment 1:
(1) the 1000g boehmite (contains Al
2O
376%) powder and 17.5g basic carbonate cobalt powder after the 54g molybdenum oxide powder mixes, add rare nitric acid (20g/100ml) 150ml, H
2O1000ml mixes and pinched 30 minutes, and through the banded extruder extrusion molding, extrudate is after 110 ℃ of dryings, again 530 ℃ of roastings 3 hours.
(2) the 136g citric acid is dissolved in 320ml H
2Among the O, add the 83g basic cobaltous carbonate, boil dissolving, after the cooling, add 25% ammoniacal liquor again to 500ml.Add the 289g ammonium molybdate in above-mentioned solution, the dissolving back transfers to 1000ml with 25% ammoniacal liquor with liquor capacity, and is airtight, stablizes 3 hours at 60 ℃ of constant temperature.
(3) get the semi-finished product 500g of (1) gained, place rotary drum, the maceration extract 385ml for preparing with (2) sprays.Spray and take out material in 110 ℃ of dryings after finishing.Again in air in 530 ℃ of roastings 3 hours, catalyst of the present invention.
Embodiment 2
This routine catalyst preparation process and example 1 are similar, and just 15% of group vib and VIII family metal component adds by coextruding method.
Embodiment 3
This routine catalyst preparation process and example 1 are similar.Just 35% of group vib and VIII family metal component adds by coextruding method.
Comparative example 1
This routine catalyst is except that used maceration extract adopts following compound method, and other each step is all with example 1.
The used maceration extract compound method of this routine catalyst is: with the 289g ammonium molybdate, 185g cobalt nitrate (six water) is dissolved in 15% ammonia spirit, after treating all to dissolve, with 15% ammoniacal liquor solution is transferred to 1000ml, promptly gets maceration extract.
Comparative example 2
This routine catalyst preparation process and example of the present invention 1 catalyst preparation process are similar.Just group vib and VIII family metal component have 50% to add by coextruding method.
Comparative example 3
This routine catalyst preparation process and example of the present invention 1 catalyst preparation process are similar.Just group vib and VIII family metal component have 75% to add by coextruding method.
Comparative example 4
The VIB of this routine catalyst and VIII family component adopt step impregnation method to support.
(1) the 1000g boehmite (contains Al
2O
376%) powder adds rare nitric acid (20g/100ml) 150ml, H
2O1000ml after mixing, mixes and pinched 15 minutes, through the banded extruder extrusion modling.Extrudate again 550 ℃ of following roastings 3 hours, gets this routine catalyst carrier after 110 ℃ of dryings.
(2) get (1) carrier 500g, place rotary drum.Containing CoO with 400ml is that basic cobaltous carbonate-ammonia spirit of 6.58g/100ml sprays.Spray and take out material in 110 ℃ of dryings after finishing.Again in air in 530 ℃ of roastings 3 hours.
(3) get (2) gained semi-finished product 500g, place rotary drum, contain MoO with 385ml
332.46g/100ml ammonium molybdate-ammonia spirit spray.Spray finish after, take out material in 110 ℃ of dryings.Again in air in 530 ℃ of roastings 3 hours, finished catalyst.
Table 2 has been listed the main physical and chemical and the hydrodesulfurization relative activity of example of the present invention and each comparative example catalyst.