Mineral oils: processes and products – Chemical conversion of hydrocarbons – Cracking
Reexamination Certificate
2000-11-29
2002-12-31
Yildirim, Bekir L. (Department: 1764)
Mineral oils: processes and products
Chemical conversion of hydrocarbons
Cracking
C208S111300, C208S111350
Reexamination Certificate
active
06500330
ABSTRACT:
The present invention relates to hydrocracking hydrocarbon feeds, with a catalyst comprising at least one amorphous or poorly crystallized matrix of the oxide type, at least one element (metal) of group VB (group 5 according to the new coding of the period classification of the elements: Handbook of Chemistry and Physics, 76th edition, 1995-1996, inside first cover page), preferably niobium, at least one zeolite Y not globally dealuminized, at least one promoter element chosen from the group consisting of boron, phosphorus and silicon, optionally at least one element (metal) chosen from group VIB and/or group VIII (group 6 and groups 8, 9 and 10 according to the new coding of the period classification of the elements), preferably molybdenum and tungsten, cobalt, nickel and iron. The catalyst also optionally comprises at least one element of group VIIA (halogen group, group 17 according to the new coding of the periodic classification of the elements), such as, for example, fluorine.
Hydrocarbon feeds, such as petroleum cuts, cuts produced from coal containing aromatic and/or olefinic and/or naphthenic and/or paraffinic compounds, the said feeds optionally comprising metals, and/or nitrogen, and/or oxygen, and/or sulphur can be beneficially hydrocracked according to the invention.
Hydrocracking of heavy petroleum cuts is a very important process in refining with which, starting from excess heavy feeds of low value, lighter fractions such as gasolines, jet fuels and light gas oils can be produced, which the refiner requires in order to adapt his production to the demand structure. Some hydrocracking processes also allow production of a highly purified residue which can constitute excellent bases for oils. In contrast to catalytic cracking, the advantage of catalytic hydrocracking is that middle distillates, jet fuels and gas oils of very good quality are provided. The gasoline produced has an octane index much lower than that produced from catalytic cracking.
The catalysts used in hydrocracking are all of the bifunctional type combining an acid function and a hydrogenating function. The acid function is carried by supports of large surface area (generally 150 to 800 m
2
.g
−1
) having a superficial acidity, such as halogenated (in particular chlorinated or fluorinated) aluminas, combinations of oxides of boron and aluminium, amorphous silica-aluminas and clays. The hydrogenating function is carried either by one or more metals of group VIII of the periodic classification of the elements, 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 classification, such as molybdenum and tungsten, and at least one metal of group VIII.
The equilibrium between the two acid and hydrogenating functions is the fundamental parameter which regulates the activity and selectivity of the catalyst. A weak acid function and a strong hydrogenating function give catalysts of low activity working in general at an elevated temperature (greater than or equal to 390° C.) and a low hourly volume velocity (the HVV, expressed in volume of feed to be treated per unit volume of catalyst and per hour, is generally less than or equal to 2), but having a very good selectivity in middle distillates. Conversely, a strong acid function and a low hydrogenating function give catalysts which are active but have less good selectivities in middle distillates. The search for a suitable catalyst will therefore be centred on a judicial choice of each of the functions to adjust the catalyst activity/selectivity relationship.
It is thus one of the great advantages of hydrocracking to have a high flexibility at various levels: flexibility at the level of the catalysts used, which leads to a flexibility in the feedes to be treated, and at the level of the products obtained. A parameter which is easy to control is the acidity of the catalyst support.
The conventional catalysts of catalytic hydrocracking are in the great majority made up of weakly acid supports, such as amorphous silica-aluminas, for example. These systems are more particularly used to produce middle distillates of very good quality, and also, if their acidity is very weak, oil bases.
Among the supports of little acidity is found the family of amorphous silica-aluminas. Many catalysts on the hydrocracking market are based on silica-alumina combined either with a metal of group VIII or, preferably, if the contents of heteroatomic poisons in the feed to be treated exceed 0.5% by weight, a combination of sulphides of metals of groups VIB and VIII. These systems have a very good selectivity in middle distillates, and the products formed are of good quality. The less acid catalysts among these can also produce lubricant bases. The disadvantage of all these catalytic systems based on an amorphous support is, as has been said, their low activity.
On the other hand, simple sulphides of elements of group VB have been described as constituents of catalysts for hydrorefining hydrocarbon feeds, such as, for example, niobium trisulphide in the patent U.S. Pat. No. 5,294,333. Mixtures of simple sulphides comprising at least one element of group VB and an element of group VIB have also been tested as constituents of catalysts for hydrorefining hydrocarbon feedes, such as, for example, in the patent U.S. Pat. No. 4,910,181 or the patent U.S. Pat. No. 5,275,994.
Research work carried out on zeolites and on the active hydrogenating phases led surprisingly to the discovery of a catalyst for hydrocracking hydrocarbon feeds comprising at least one amorphous or poorly crystallized, generally porous matrix, such as alumina, at least one element of group VB of the periodic classification of the elements, such as tantalum, niobium and vanadium, preferably niobium, at least one zeolite Y not globally dealuminized and with a unit cell parameter (or crystalline parameter) greater than 2.438 nm, preferably greater than 2.442 nm, and very preferably greater than 2.455 nm, and a global SiO2/Al2O3 ratio of less than 8, preferably less than 7.5, very preferably less than 7, and at least one promoter element chosen from the group consisting of boron, phosphorus and silicon . . .
The catalyst also optionally comprises at least one element of group VIB of the said classification, such as chromium, molybdenum and tungsten, preferably molybdenum or tungsten, and more preferably molybdenum, optionally an element of group VIII, that is to say an element chosen from the group consisting of: Fe, Ru, Os, Co, Rh, Ir, Ni, Pd and Pt, preferably iron, cobalt, nickel or ruthenium, and optionally an element of group VIIA, preferably fluorine.
The catalyst has a hydrocracking activity which is greater than that of catalytic formulations based on an element of group VIB which are known from the prior art.
The catalyst of the present invention generally comprises, in % by weight with respect to the total weight of the catalyst:
0.1 to 99.8%, preferably 0.1 to 90%, more preferably 0.1 to 80%, and very preferably 0.1 to 70% of at least one zeolite Y not globally dealuminized and having a unit cell parameter which is greater than 2.438 nm, preferably greater than 2.442 nm, and very preferably greater than 2.455 nm, and a global SiO2/Al2O3 ratio of less than 8, preferably less than 7.5, very preferably less than 7,
0.1 to 60%, preferably 0.1 to 50%, and more preferably 0.1 to 40% of at least one element chosen from group VB,
0.1 to 99%, preferably 1 to 99% of at least one amorphous or poorly crystallized porous mineral matrix of the oxide type,
0.1 to 20%, preferably 0.1 to 15%, and more preferably 0.1 to 10% of at least one promoter element chosen from the group consisting of boron, phosphorus and silicon, excluding the silicon optionally contained in the zeolite, it being possible for the catalyst also to comprise:
0 to 60%, preferably 0.1 to 50%, and more preferably 0.1 to 40% of at least one element chosen from the elements of group VIB and group VIII, and
0 to 20%, preferably 0.1 to 15%, and more pre
Benazzi Eric
Kasztelan Slavik
Marchal-George Nathalie
Institut Francais du Pe'trole
Millen White Zelano & Branigan P.C.
Yildirim Bekir L.
LandOfFree
Hydrocracking process with catalyst comprising a zeolite Y... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Hydrocracking process with catalyst comprising a zeolite Y..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Hydrocracking process with catalyst comprising a zeolite Y... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2928993