A kind of hydrogenation nickel removal Catalysts and its preparation methodTechnical field
The present invention relates to a kind of hydrogenation nickel removal Catalysts and its preparation method, relate in particular to a kind of heavy-oil hydrogenation nickel removal Catalysts and its preparation method.
Background technology
Heavy oil includes the Atmospheric vacuum residual oil in crude oil, heavy crude, oil-sand, synthetic heavy oil product etc..Containing the impurity such as substantial amounts of heavy metal (such as Ni, V), sulfur, nitrogen in this oil, and Colophonium and gum level higher, therefore at present before mink cell focus hydrogenation plant, be all filled with hydrogenation protecting agent and Hydrodemetalation catalyst.Such catalyst needs bigger aperture and pore volume, meets demetalization and the needs of asphalitine conversion.Catalyst can be typically in more than 15nm in several apertures, and general alumina support sintering temperature is all more than 800 DEG C, and the temperature that molybdenum oxide distils in the catalyst is 800 DEG C.If roasting at a lower temperature, it may be considered that kneading mode carries out catalyst preparing, but catalyst pore-size distribution does not reach the needs of demetalization performance.
The physics expanding agents such as the white carbon black such as US4448896, US4102822, starch expand the aperture of alumina support.But pore size distribution is not concentrated, intensity is poor.CN1209355A proposes a kind of macropore alumina supporter and preparation method thereof, higher than room temperature when, boehmite raw material is carried out peptization or ripening, the material after the molding compound containing ammonium ion processes, preparing the pore volume that carrier hole diameter is 10 ~ 20nm and account for the 70 ~ 85% of total pore volume, its processing procedure is more complicated.
CN95105207, US4562059 etc. disclose a kind of method that swing method prepares hydrogenation catalyst.The method is in preparing carrier process, it is necessary to swing repeatedly, relatively complicated, is industrially difficulty with.
US4443558 adopts the method for kneading to prepare catalyst, one-step shaping completely, and preparation cost is low.But catalyst adds the method for alkali after adopting first acid adding, the addition of strong acid causes that catalyst aperture diminishes, and pore volume reduces.US5089453 adopts kneading method to prepare residual oil hydrocatalyst, and with phosphorus as auxiliary agent.Owing to metal is in the alumina powder added with the form of metal salt in powder, it is easy to cause Active components distribution uneven with, catalyst strength is poor.
CN99113299 adopts complete kneading method to prepare high activity hydrotransforming catalyst for residual oil, and the method introduces molecular sieve in preparation process, improves acidity of catalyst, and the de-carbon residue performance of catalyst is further promoted.The method preparation is not suitable for catalyst for demetalation, and catalyst for demetalation needs relatively low acidity, and otherwise catalyst carbon deposition is too high, and inactivation is very fast.
In residual oil or mink cell focus hydroprocessing processes, the metal deposit such as vanadium and nickel in raw material is the main cause of catalysqt deactivation, and the demetallization per of usual Hydrodemetalation catalyst maintains about 70%, but for metallic nickel, being relatively difficult to elimination, general nickel removal rate will lower than vanadium removal rate.Because vanadium is with VO2+Form exist, in porphyrin compound combine can will lower than metallic nickel, thus vanadium metal be easier elimination.In current high-sulfur residual oil, content of vanadium is higher, and there is no problem for existing residuum hydrogenating and metal-eliminating catalyst elimination metal, and demetallization per is substantially all more than 80%, but in high nitrogen residual oil, metallic nickel content is higher, and demetallization per substantially will lower than 50%.Therefore, for present stage residuum hydrogenating and metal-eliminating catalyst, mainly consider to improve the nickel removal effect in demetalization performance.
Main in present stage Hydrodemetalation catalyst R&D process consider to hold metal problem, improve catalyst pores hold or (with) aperture.In demetallization per raising, mainly from catalyst grade part system's consideration or technical process temperature raising.US4448896, US4102822, CN200410037669, CN200410071123, CN1209355A etc. mainly prepare catalyst from the viewpoint of carrier and hold metal ability, improve catalyst stability.Currently without being specifically designed for raising nickel removal aspect of performance catalyst preparation technology explanation.
Summary of the invention
For feature nickelic in current part residual oil raw material, the present invention provides a kind of high-activity hydrogenation nickel removal Catalysts and its preparation method.
A kind of preparation method being hydrogenated with nickel removal catalyst, comprises the steps: that (1) weighs shaped alumina alumina supporter；(2) preparation active metal impregnation liquid, carries out active metal dipping by shaped alumina alumina supporter, then dried；(3) dried catalyst is sequentially carried out high temperature-low temperature roasting；(4) catalyst after roasting adopts ammonium gluconate solution soaking to process, prepared final catalyst scrubbed, dried.
The inventive method, in step (1), shaped alumina alumina supporter can also can be made by oneself according to prior art for commercial goods.The pore structure of shaped alumina alumina supporter meets the needs of catalyst for demetalation performance.Described shaped alumina alumina supporter is spherical, bar shaped, sheet-shaped or granulated, and pore diameter range is 10 ~ 30nm, it is desirable to be 15 ~ 25nm.
The inventive method, in step (2), the active component of active metal impregnation liquid is VIII and group vib metal, and wherein group VIII metal is Co and Ni, and group vib metal is Mo and W.In catalyst, group VIII metal counts weight content for 5-15% with oxide, and group vib metal counts weight content for 1-5% with oxide.Baking temperature is 100 ~ 250 DEG C, and drying time is 1 ~ 6h.
The inventive method, possibly together with appropriate ethylenediaminetetraacetic acid in step (2) activity component impregnation liquid, the mass concentration of edta solution is 1%-10%, it is preferable that 3-8%.Add appropriate ethylenediaminetetraacetic acid and can significantly improve nickel removal efficiency.
The inventive method, step (2) active metal dipping included volume impregnation, incipient impregnation or spray dipping, and dip time is 1-5 hour.
The inventive method, in the high temperature-low temperature roasting process described in step (3), high temperature range is 600 DEG C ~ 450 DEG C, and low temperature range is less than 450 DEG C.
The inventive method, can also be divided into high temperature section, middle-temperature section, low-temperature zone by roasting process in step (3)；High-temperature temperature is: 600 ~ 500 DEG C, and middle temperature temperature is: 400 ~ 350 DEG C, and cryogenic temperature is: 300 ~ 150 DEG C；Every section of roasting time is at least 0.5 ~ 1h.Preferred high temperature section roasting adopts the mode of microwave calcining.What microwave calcining added together ethylenediaminetetraacetic acid synergism has optimum nickel removal effect.
The inventive method, adopts gluconic acid aqueous ammonium in step (4), the mass concentration of gluconic acid aqueous ammonium is 5-30%, it is preferable that 10-20%.Immersion adopted volume to soak, and soak time is 0.5-5h, and soaking temperature is 40-80 DEG C, it is preferable that soak time is 1-3h, and soaking temperature is 50-70 DEG C.Wash to the mass content of ammonium ion in catalyst less than 0.5%, it is preferred to 0.05-0.3.Catalyst after adopting gluconic acid aqueous ammonium to process roasting can reduce catalyst activity component with the interaction between carrier, and then improves the activity of catalyst.
A kind of catalyst adopting above method to prepare, in catalyst, group VIII metal counts weight content for 5-15% with oxide, and group vib metal counts weight content for 1-5% with oxide, and pore diameter range is 15 ~ 20nm, and the active metal sulphides number of plies is 5 ~ 10.
The inventive method is from traditional preparation methods the difference is that baking modes is different, and this baking modes can reduce the carrier impact on active metal, advantageously forms the more active metal phase being suitable to nickel removal.Catalyst prepared by the present invention, the sulfide number of plies is more, has good active structure, is conducive to active center activity to improve and the formation of activity phase.The more sulfide number of plies is conducive to abolishing sterically hindered in aromatic ring of NI, S etc. in asphalitine and colloid, improves desulfurization and nickel removal performance.
Detailed description of the invention
Further describe the present invention program and effect below in conjunction with embodiment, but be not limited to following example.Transmission electron microscope is adopted to carry out catalyst vulcanization thing analysis.
Embodiment 1
Weigh industry demetalization bar shaped alumina support (Sinopec catalyst Co. Fushun branch company produces, and aperture is 18nm) 100g；Preparation Mo-Ni-P solution, molybdenum oxide concentration is: 12.7g/100ml, and nickel oxide concentration is: 3.0g/100ml；At 180 DEG C, 1.5h is dried after taking 100ml solution impregnation 3h；Dry terminate after, first carry out roasting 0.5h at 600 DEG C, then roasting 1h at 350 DEG C again, last at 250 DEG C of roasting 0.5h, the gluconic acid aqueous ammonium adopting mass concentration to be 10% crosses the catalyst after volume soaks above-mentioned roasting, and the bubble time is 3h, and soaking temperature is 50 DEG C.Washing less than 0.5%, prepares catalyst A to the mass content of ammonium ion in catalyst after drying.
Embodiment 2
Being the ethylenediaminetetraacetic acid of 5% with containing mass concentration in embodiment 1 simply preparation Mo-Ni-P solution, prepared catalyst is A1.
Embodiment 3
It is different in that employing microwave calcining, prepared catalyst are A2 with embodiment 1.
Embodiment 4
It is different in that employing microwave calcining, prepared catalyst are A12 with embodiment 2.
Embodiment 5
Weigh industry catalyst for demetalation carrier (catalyst Fushun branch company produces, and aperture is 15nm) 100g;Preparation Mo-Ni-P solution, molybdenum oxide concentration is: 12.7g/100ml, and nickel oxide concentration is: 3.0g/100ml；Take 100ml solution impregnation, carry out catalyst soakage 3h, dry 5h at 120 DEG C；Dry terminate after, first carry out microwave calcining 2h at 500 DEG C, then roasting 1h at 400 DEG C again, last at 150 DEG C of roasting 0.5h, the gluconic acid aqueous ammonium adopting mass concentration to be 20% crosses the carrier after volume soaks above-mentioned roasting, and soak time is 1h, and soaking temperature is 70 DEG C.Washing less than 0.5% to the mass content of ammonium ion in catalyst, dries and prepares catalyst B.
Embodiment 6
Step is with embodiment 1, and institute is 550 DEG C the difference is that high temperature section temperature, prepares catalyst C.
Embodiment 7
Step is with embodiment 1, and institute is 380 DEG C the difference is that middle-temperature section temperature, prepares catalyst D.
Comparative example 1
Weigh industry catalyst for demetalation carrier (catalyst Fushun branch company produces, and aperture is 18nm) 100g;Preparation Mo-Ni-P solution, molybdenum oxide concentration is: 12.7g/100ml, and nickel oxide concentration is: 3.0g/100ml；At 180 DEG C, 1.5h is dried after taking 100ml solution impregnation 3h；After 450 DEG C of roasting 3h, prepare catalyst E.
On 200ml fixed bed hydrogenation assay device, the catalyst prepared by embodiment and comparative example being evaluated, raw oil character and 500h result of the test are in Table 1.
Table 1
By the above results it can be seen that adopt Hydrodemetalation catalyst prepared by the method, nickel removal performance significantly improves.