Catalyst that comprises a clay and an element of group VB,...

Details Catalyst that comprises a clay and an element of group VB,... Catalyst that comprises a clay and an element of group VB,...

1999-06-25

2001-06-26

Yildirim, Bekir L. (Department: 1764)

Mineral oils: processes and products

Chemical conversion of hydrocarbons

Cracking

C208S111200, C208S111300, C208S111350, C502S074000, C502S084000, C502S204000, C502S207000, C502S211000, C502S213000, C502S219000, C502S221000, C502S246000, C502S254000, C502S257000, C502S311000, C502S314000, C502S353000, C502S354000

Reexamination Certificate

active

06251261

ABSTRACT:

This invention relates to a catalyst for hydrocracking feedstocks that contain hydrocarbon, whereby said catalyst comprises at least one oxide-type amorphous or poorly crystallized matrix, at least one element (metal) of group VB (group 5 according to the new notation of the periodic table: Handbook of Chemistry and Physics, 76th Edition, 1995-1996, first inside cover page), preferably niobium, at least one clay, optionally at least one element (metal) that is selected from among group VIB and/or group VIII (group 6 and groups 8, 9 and 10 according to the new notation of the periodic table), preferably molybdenum and tungsten, cobalt, nickel and iron. The catalyst also optionally contains an element that is selected from the group that consists of boron, phosphorus and. silicon (B, P, Si) and optionally at least one element of group VIIA (group of halogens, group 17 according to the new notation of the periodic table), such as, for example, fluorine.
This invention also relates to the processes for preparation of said catalyst, as well as its use for hydrocracking feedstocks that contain hydrocarbon such as petroleum fractions, the fractions that are obtained from the carbon that contains aromatic and/or olefinic and/or naphthenic and/or paraffinic compounds, whereby said feedstocks optionally contain metals, and/or nitrogen and/or oxygen and/or sulfur.
The hydrocracking of the heavy petroleum fractions is a very important refining process that makes it possible to produce, from excess heavy feedstocks that cannot be readily upgraded, lighter fractions, such as gasolines, jet fuels and light gas oils that the refiner seeks to adapt his production to the structure of the demand. Some hydrocracking processes make it possible also to obtain a highly purified residue that can constitute excellent bases for oils. Relative to catalytic cracking, the advantage of the catalytic hydrocracking is to provide middle distillates, jet fuels and gas oils of very good quality. The gasoline that is produced has a much lower octane number than the one that is obtained from catalytic cracking.
The catalysts that are used in hydrocracking are all of bifunctional type combining an acid function with a hydrogenating function. The acid function is provided by large-surface supports (150 to 800 m
2
·g
−1
generally) that have a surface acidity, such as halogenated (particularly chlorinated or fluorinated) aluminas, combinations of boron and aluminum oxides, amorphous silica-aluminas and clays. The hydrogenating function is provided either by one or more metals of group VIII of the periodic table, such as iron, cobalt, nickel, ruthenium, rhodium, palladium, osmium, iridium and platinum, or by a combination of at least one metal of group VI of the periodic table, such as molybdenum and tungsten and at least one metal of group VIII.
The equilibrium between the two acid and hydrogenating functions is the basic parameter that controls the activity and the selectivity of the catalyst. A weak acid function and a strong hydrogenating function provide catalysts that are not very active and that work at a generally elevated temperature (greater than or equal to 390° C.) and at a low feed volumetric flow rate (the VVH that is expressed by volume of feedstock to be treated per unit of volume of catalyst and per hour is generally less than or equal to 2), but provided with a very good selectivity of middle distillates. Conversely, a strong acid function and a weak hydrogenating function provide active catalysts but have poorer selectivities of middle distillates. The search for a suitable catalyst will therefore be centered on a judicious selection of each of the functions to adjust the activity/selectivity pair of the catalyst.
It is thus one of the great advantages of hydrocracking to offer high flexibility at various levels: flexibility as far as the catalysts that are used are concerned, which ensures flexibility of the feedstocks that are to be treated and as far as the products that are obtained are concerned. An easy parameter to control is the acidity of the support of the catalyst.
The conventional catalysts of the catalytic hydrocracking consist of, for the large majority, weakly acidic supports, such as amorphous silica-aluminas, for example. These systems are more particularly used for producing middle distillates of very good quality, and also, when their acidity is very low, oil bases.
In the supports that are not very acidic is found the family of amorphous silica-aluminas. Many hydrocracking market catalysts have a combined silica-alumina base, either with a metal of group VIII or preferably when the contents of heteroatomic poisons of the feedstock that is to be treated exceed 0.5% by weight, with a combination of sulfides of the metals of groups VIB and VIII. These systems have a very good selectivity of middle distillates, and the products that are formed are of good quality. These catalysts, for the less acidic among them, can also produce lubricating bases. The drawback of all of these catalytic systems with an amorphous support base is, as has been said, their weak activity.
In contrast, simple sulfides of elements of group VB have been described as components of hydrorefining catalysts of feedstocks that contain hydrocarbon, such as, for example, the niobium trisulfide in U.S. Pat. No. 5,294,333. Mixtures of simple sulfides that comprise at least one element of group VB and an element of group VIB have also been tested as components of hydrorefining catalysts of feedstocks that contain hydrocarbon, such as, for example, in U.S. Pat. Nos. 4,910,181 or 5,275,994.
The research work that has been carried out by the applicant on clays and on hydrogenating active phases led him to discover that, in a surprising way, a catalyst for hydrocracking feedstocks that contain hydrocarbon comprises at least one generally porous, amorphous or poorly crystallized matrix such as alumina, at least one element of group VB of the periodic table, such as tantalum, niobium and vanadium, preferably niobium, at least one clay that is selected from the group that is formed by the 2:1 dioctahedral phyllosilicates such as, for example, montmorillonite, beidellite, vermiculite and the 2:1 trioctahedral phyllosilicates, such as, for example, talc, hectorite and saponite.
The phyllosilicate is preferably synthesized in a fluoride medium that is optionally bridged, whereby the phyllosilicate preferably exhibits a large reticular distance (whereby the reticular distance is the sum of the thickness of a layer and the interlayer space); clay is preferably a 2:1 dioctahedral phyllosilicate.
The catalyst also optionally comprises at least one element of group VIB of said classification, such as chromium, molybdenum and tungsten, preferably molybdenum or tungsten, even more preferably molybdenum, optionally an element of group VIII, i.e., an element that is selected from the group that consists of: Fe, Ru, Os, Co, Rh, Ir, Ni, Pd, and Pt, preferably iron, cobalt or nickel, optionally a promoter element that is selected from the group that consists of boron, silicon, and phosphorus, optionally an element of group VIIA, and preferably fluorine makes it possible to obtain activities, i.e., a conversion level, that are higher than with the catalysts that are known in the prior art.
Said catalyst exhibits a more significant hydrocracking activity than those of the catalytic formulas with a group VIB element base that are known from the prior art. Without subscribing to any particular theory, it seems that this particularly high activity of the catalysts of this invention is due to special properties of the sulfide of the element of group VB. The combination of such a sulfide that has acid properties with a phyllosilicate makes possible not only an improvement of the cracking properties but further an improvement of hydrogenating, hydrodesulfurizing, hydrodenitrating properties relative to the sulfide of the element of group VIB and in particular the molybdenum sulfide or tungsten sulfide that are usually used for the hydrogena

Affiliated with

Also associated with

Rating

Catalyst that comprises a clay and an element of group VB,... does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Catalyst that comprises a clay and an element of group VB,..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Catalyst that comprises a clay and an element of group VB,... will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2484764