ES2267296T3 - FLEXIBLE PROCEDURE FOR PRODUCTION OF MEDICINAL OILS AND OPTIONALLY INTERMEDIATE DISTILLATES. - Google Patents

Abstract

Procedure for the production of oils and high quality medium distillates from a hydrocarbon filler, at least 20% volume of which boils above 340 ° C, a procedure consisting successively in the following stages: (a) hydrotreatment performed at a temperature of 330-450 ° C under a pressure of 5-25 Mpa, with a spatial velocity of 0, 1-6 h-1, in the presence of hydrogen in a volumetric ratio of hydrogen / hydrocarbon of 100-

Description

Flexible oil production procedure medicinal and optionally intermediate distillates.

The present invention has as its object a Improved process of manufacturing very high base oils quality, that is, they have a high viscosity index (VI), a low aromatic content, good UV stability and low pour point, from oil fractions that have a boiling point higher than 340 ° C, possibly with production Simultaneous medium distillates (diesel and kerosene especially) of very high quality, that is, that they have a low content in aromatic and a low pour point.

Prior art

High quality lubricants are of one paramount importance for the proper functioning of the machines modern cars and trucks.

These lubricants are more frequently obtained by a succession of refining stages that allow improve the properties of an oil fraction. In particular, a treatment of heavy oil fractions is necessary with high contents in linear or little branched paraffins with the in order to obtain good quality base oils and this with the best possible returns, for an operation that aims to remove linear or very unbranched paraffins from charges that will then be used as base oils.

Indeed, high molecular weight paraffins that are linear or very unbranched and that are present in oils lead to high pour points and, therefore, to Coagulation phenomena for low temperature uses. With in order to decrease the values of the pour points, these linear or very unbranched paraffins should be removed Totally or partially.

You can perform this operation by extraction by solvents such as toluene / methyl ethyl ketone mixtures or methyl isobutyl ketone; there is talk about deparaffination with methyl ethyl ketone ("MEK") or with methyl isobutyl ketone ("MIBK"). However, these techniques are expensive, not always easy to practice and lead to the formation of by-products, the raw paraffins

Another means is catalytic treatment in presence or absence of hydrogen and, given its shape selectivity, zeolites are among the catalysts most used.

Catalysts based on zeolites, such as ZSM-5, ZSM-11, ZSM-12, ZSM-22, ZSM-23, ZSM-35 and ZSM-38 for use In these procedures.

Object of the invention

The applicant has dedicated her efforts to investigation to the development of an improved procedure of manufacture of very high quality lubricating oils.

The present invention thus relates to a chain of procedures for the joint manufacture of base oils of very high quality and medium distillates (diesel especially) of very high quality. The oils obtained have a high viscosity index (VI), a low aromatic content, a low volatility, good UV stability and a low point of fluidity, from oil fractions that have a point of boiling above 340 ° C.

In particular, and contrary to chains of usual procedures or from prior art state, this procedure is not limited in the quality of the oils product that allows to obtain; in In particular, a judicious choice of operating conditions allows to obtain medicinal white oils (that is, from excellent qualities). More specifically, the invention relates to with a procedure for the production of high quality oils and of high quality medium distillates from a load hydrocarbon of which at least 20% by volume boils by above 340 ° C, a procedure that successively entails following stages:

(to)

hydrotreatment performed at a temperature of 330-450 ° C under a pressure of 5-25 Mpa, with a spatial velocity of 0.1-6 h -1, in the presence of hydrogen in a volumetric ratio of hydrogen / hydrocarbon of 100-2,000 and in the presence of an amorphous catalyst consisting of at least one metal of group VIII and at least one metal from group VI B;

(b)

hydrofissuring, without separation intermediate of the effluent obtained from hydrotreatment, being Hydrofissuring performed at a temperature of 340-430 ° C under a pressure of 5-25 Mpa, with a spatial velocity of 0.1-5 h -1, in the presence of hydrogen and in the presence of a catalyst that it contains at least one zeolite and which also contains at least one element of group VIII and at least one element of group VI B;

(C)

atmospheric distillation without vacuum distillation of the effluent obtained from the hydrofisuration for separate the gases from the liquid;

(d)

catalytic dewaxing of at least a liquid fraction obtained by atmospheric distillation and that contains boiling point compounds higher than 340 ° C, dewaxing at a temperature of 200-500ºC low a total pressure of 1-25 Mpa, with a speed hourly volume of 0.05-50 h <-1>, with 50-2,000 l of hydrogen / l load, in the presence of a catalyst that also includes at least one element with hydro-dehydrogenating function and at least one screen molecular whose microporous system has at least one type main channels with pore openings that have 9 or 10 T atoms, with T being selected from the group formed by Si / Al, P, B, Ti, Fe and Ga, alternating with an equal number of atoms of oxygen, being the distance between two pore openings accessible of 9 or 10 T atoms of at most 0.75 mm and presenting said sieve in the n-dean test a reason 2-methylnonano / 5-methyltilano superior to 5;

(and)

be subject the dewaxed effluent directly to a treatment of hydro-finishing done at a temperature of 180-400 ° C, which is lower than the temperature of the catalytic dewaxing at least 20 ° C and at most 200 ° C, under a total pressure of 1-25 Mpa, with a hourly volumetric speed of 0.05-100 h -1, in presence of 50-2,000 liters of hydrogen / liter of loading and in the presence of an amorphous catalyst for hydrogenation of the aromatics, which includes at least one metal selected from the group of group VIII metals and group VI metals B;

(F)

be subject the effluent from the hydro-finishing treatment to a distillation stage consisting of an atmospheric distillation and a vacuum distillation to separate at least a fraction of oil of a boiling point higher than 340 ° C and presenting a point of fluidity below -10 ° C, a weight content of compounds aromatic less than 2% and a VI greater than 95 and a viscosity at 100 ° C of at least 3 cSt (that is, 3 mm 2 / s), and to separate possibly at least a fraction of medium distillate that has a pour point of less than or equal to -20 ° C, a content of aromatics of at most 2% by weight and a content of Polyaromatic at most 1% by weight.

Detailed description of the invention

The method according to the invention comprises the following stages:

Stage (to)

Hydrotreatment

The hydrocarbon load from which it they obtain the oils and eventually the high distilled media quality has at least 20% in volume that boils above 340 ° C.

You can treat, therefore, very varied loads by The procedure.

A load can be, for example, LCO (light cycle oil), vacuum distillates from distillation direct from the gross or conversion units such as the FCC, the coke or visorreduction, or coming from units of extraction of aromatics, or from desulfurization or hydroconversion of RAT (atmospheric waste) and / or RSV (waste under vacuum), or the load may also be a deasphalted oil, or also any mixture of the aforementioned charges. The list Previous is not limiting. In general, the charges that suit for the purpose of oils have a boiling point initial higher than 340ºC and better still higher than 370ºC.

The load is initially subjected to a hydrotreatment, during which you contact, in the presence of hydrogen, with at least one catalyst that carries an amorphous support and at least one metal that has a guaranteed dehydrogenating function, for example, for at least one element of group VI B and at least one element of group VIII, at a temperature between 330 and 450 ° C, preferably between 360 and 420 ° C, under a pressure between 5 and 25 Mpa, preferably less than 20 Mpa, the space velocity between 0.1 and 6 h <-1> being comprised, preferably between 0.3 and 3 h <-1>, and the amount of hydrogen introduced is such that the volumetric ratio of hydrogen / hydrocarbon is between 100 and 2,000.

In the course of the first stage, the use of a catalyst that favors hydrogenation with respect to cracking, used in thermodynamic and kinetic conditions appropriate, allows a significant reduction of content in condensed polycyclic aromatic hydrocarbons. In these conditions, most of the nitrogen and sulfur products of the cargo. This operation it allows, therefore, to eliminate two types of compounds of which it is said which are inhibitors of the zeolitic catalyst that is used in that follows the procedure.

This first stage allows, performing a presetting of the load to be treated, adjust the properties of the oil base at the exit of this first stage depending on the quality of the oil base that you want to obtain As a result of the procedure. Advantageously, it can be done this regulation acting on the nature and quality of catalyst used in the first stage and / or over temperature of this first stage, so that the index of viscosity for oil base, boiling point fraction higher than 340ºC, at the exit of this stage. Viscosity index obtained, before dewaxing, is preferably between 80 and 150, and better between 90 and 140, even between 90 and 130.

The support is usually based on (preferably consists essentially of) alumina or of amorphous silica-alumina; may also contain rust of boron, magnesia, zirconia, titanium oxide or a combination of these oxides. The hydro-dehydrogenating function is preferably carried out by at least one metal or compound of metal of groups VIII and VI, preferably selected (s) from: molybdenum, tungsten, nickel and cobalt.

This catalyst may advantageously contain match; indeed, it is known in the art that the compound provides Two advantages to hydrotreatment catalysts: a facility of preparation at the time especially of the impregnation of nickel and molybdenum solutions and better activity of hydrogenation

Preferred catalysts are those NiMo and / or NiW catalysts on alumina, also catalysts NiMo and / or NiW on alumina contaminated with at least one element included in the group of atoms formed by phosphorus, the boron, silicon and fluorine, or also NiMo and / or catalysts NiW on silica-alumina, or on silica-alumina-titanium oxide contaminated or not by at least one element included in the group of atoms formed by phosphorus, boron, fluoride and silicon.

The total concentration of metal oxides of Groups VI and VIII are between 5 and 40% by weight and preferably between 7 and 30% and the weight ratio expressed in metal oxide between metal (or metals) of group VI and metal (or metals) of group VIII is preferably between 20 and 1.25 and even more preferably between 10 and 2. The concentration of phosphorus oxide P2O5 will be less than 15% by weight and preferably 10% by weight.

The product obtained at the exit of this first stage is sent to a second catalyst in a second stage without intermediate separation of ammonia (NH3) and sulfur hydrogen (H2S) or distillation.

Stage (b)

Hydrocracking

The effluent from the first stage (a) in its entirety on the catalyst of the second  step (b) in the presence of hydrogen, where it is hydrofissured in presence of a bifunctional catalyst that carries an acid function zeolitic and a metallic function hydro-dehydrogenating

During this stage, the compounds polyaromatic and polynaphthenoaromatic partially and / or totally hydrogenated during the first stage are hydrofissured on the Acid sites to lead to paraffin formation. These paraffins, in the presence of a bifunctional catalyst, may suffer an isomerization and then eventually a hydrofisuration to lead, respectively, to the formation of isoparaffins and of lighter cracking products.

The conversion of polyaromatic compounds in several cores it needs prior to cracking a hydrogenation

The second stage catalyst includes a zeolite, a support and a function hydro-dehydrogenating

The hydro-dehydrogenating function it is advantageously obtained by a combination of metals of the groups VI B (for example molybdenum and / or tungsten) and / or metals Group VIII preferably non-noble (for example cobalt and / or nickel) of the periodic classification of the elements. Preferably, this catalyst may also contain at least a promoter element deposited on the catalyst surface, element included in the group formed by phosphorus, boron and silicon and advantageously phosphorus.

The total metal concentration of the groups VI B and VIII, expressed in metal oxides with respect to support, is generally between 5 and 40% by weight, preferably between 7 and 30% by weight. The weight ratio (expressed in metal oxides) of Group VIII metals with with respect to metals of group VI B is preferably comprised between 0.05 and 0.8, preferably between 0.13 and 0.5.

This type of catalyst can advantageously contain phosphorus, whose content, expressed in phosphorus oxide P 2 O 5 with respect to the support, will be generally lower 15% by weight, preferably less than 10% by weight.

Boron and silicon contents are lower 15% by weight and preferably less than 10% by weight (expressed in oxide).

The amorphous or poorly crystallized support is selected from the group consisting of alumina, silica, silica alumina, alumina-boron oxide, magnesia, silica-magnesia, zirconia, titanium oxide or clay, alone or in mixtures.

The zeolite is advantageously selected from the group formed by zeolite Y (structural type FAU, faujasite) and the zeolite Beta (structural type BEA) according to the nomenclature developed in "Atlas of zeolites structure types", W.M. Meier, D.H. Olson and Ch. Baerlocher, 4th Revised Edition 1996, Elsevier

The weight content in zeolite is between 2 and 80% and preferably between 3 and 50% with respect to the final catalyst, and advantageously between 3 and 25%

The zeolite may eventually be contaminated by metallic elements, such as family metals of rare earths, especially lanthanum and cerium, or noble or non-noble metals of group VIII, such as platinum, palladium, ruthenium, rhodium, iridium, iron and other metals like manganese, zinc and magnesium.

An H-Y acid zeolite particularly advantageous is characterized by different specifications: a molar ratio SiO_ {2} / Al_ {2} O_ {3} between about 6 and 70 and preferably between about 12 and 50; a sodium content of less than 0.15% in weight determined on the calcined zeolite at 1,100 ° C; a parameter crystalline a of the elementary mesh between 24.58 x 10-10 and 24.24 x 10-10 m and preferably between 24.38 x 10-10 m and 24.26 x 10-10 m; a CNa capacity of sodium ion recovery, expressed in grams of Na per 100 grams of modified, neutralized and then calcined zeolite, greater than about 0.85; a specific surface determined by the B.E.T. greater than approximately 400 m 2 / g and preferably greater than 550 m 2 / g; a capacity of water vapor adsorption at 25 ° C for a partial pressure of 2.6 torr (that is, 34.6 MPa) greater than about 6%; a porous distribution, determined by nitrogen fisisorption that it comprises between 5 and 45% and preferably between 5 and 40% of the total porous volume of the zeolite contained in pores of diameter between 20 x 10-10 m and 80 x 10-10 m and between 5 and 45% and preferably between 5 and 40% of total porous volume of the zeolite contained in pores in diameter greater than 80 x 10-10 m and generally less than 1,000 x 10-10 m, the remainder being the porous volume contained in the pores of diameter less than 20 x 10-10 m.

A preferred catalyst essentially contains at least one group VI metal and / or at least one group VIII metal No noble, zeolite Y and alumina.

An even more preferred catalyst contains essentially nickel, molybdenum, a zeolite and as it has been defined above and alumina.

The operating conditions under which Performs this second stage (b) are important.

The pressure will be maintained between 5 and 25 MPa, advantageously between 5 and 20 MPa and preferably between 7 and 15 MPa and the special speed will be between 0.1 h -1 and 5 h <-1> and preferably between 0.5 and 4.0 h <-1>.

The temperature is adjusted in the second stage (b) to obtain viscosity and V.I. desired Is understood between 340 and 430 ° C and in general it is advantageously between 370 and 420 ° C.

These two stages (a) and (b) can be performed on the two types of catalysts in different reactors (two or several), or, and preferably, on at least two catalytic beds installed in the same reactor.

From the effluent outlet of the hydrofisher, It separates the hydrogen and the effluent is then subjected directly to an atmospheric distillation (step c) to separate gases (such such as ammonia and sulfur hydrogen (H2S) formed, so like the other light gases that would be present, eventually hydrogen...). At least one liquid fraction is obtained that contains products whose boiling point is higher than 340ºC.

It can be advantageously distilled under pressure atmospheric to obtain several fractions (gasoline, kerosene and diesel, for example) with a boiling point of at most 340 ° C and a fraction (called residue) with an initial boiling point higher than 340ºC (and better than 370ºC).

This fraction has a VI before dewaxing between 95 and 165 and preferably at minus 110

According to the invention, this fraction (residue) will be then treated in the catalytic dewaxing stage, it is say, without undergoing vacuum distillation.

In a variant of the procedure, the residue undergoes, before being catalytically dewaxed, an extraction of the aromatic compounds (which constitute a stage (c ')). This extraction is carried out by any known means and solvents most used are furfurol and N-methylpyrrolidone.

Naphthenoaromatic compounds are like this extracted and the refined obtained has a viscosity index higher than the residue entering the extraction stage. Through this operation, the VI of the product obtained is still increased in the hydro-finishing stage.

In another embodiment more focused on an objective of medium distillate production, decreases the point of cutting and, instead of cutting at 340 ° C as before, they may, by For example, include diesel and possibly kerosene in the fraction containing the compounds that boil above 340 ° C. For example, a fraction with boiling point is obtained initial of at least 150 ° C.

On the contrary, the residue may suffer a extraction of aromatic compounds before being dewaxed catalytically This extraction is carried out by any means known, furfurol being the most frequently used. Be employ the usual operating conditions.

       \ newpage
    

The refined obtained has an index of viscosity higher than the index of the incoming residue. It increases like this even the VI of the product obtained from the hydro-finishing.

The fraction thus obtained containing said Compounds will be treated directly in catalytic dewaxing, being or not being treated the other fractions (150ºC) by separated in catalytic dewaxing in this mode of realization.

In general, it is called in this text middle distillates at the fraction (s) with point of initial boiling of at least 150 ° C and final that goes until before residue, that is, generally up to 340 ° C or preferably up to 370 ° C.

An advantage of this conversion procedure (hydrotreatment and hydrofisuration) described (thus using a zeolitic type catalyst) is that it allows in general to manufacture bases of lubricating oils that have a viscosity greater than that obtained by an amorphous catalyst at the same conversion. At course of the hydrofisuration process, the viscosity at 100 ° C of the boiling point fraction greater than 340 ° C no converted, and preferably higher than 370 ° C, is a function decreasing conversion level obtained.

When this conversion level is high (more beyond 70%), the viscosity of the residue obtained with a catalyst  amorphous is such that it cannot be used to produce grades more viscous lubricating oils (500 N and Bright Stock). This limitation disappears when the zeolitic catalyst is used previously described.

Thus, the ratio between the viscosity at 100 ° C of the 370 ° C hydrofissuring residue, obtained by a process which uses only non-zeolitic catalysts (V 100A), and the viscosity at 100 ° C of the hydrocracking residue 370 ° C +, obtained by our procedure (V_ {100Z}) and to it conversion, this reason (V_ {100A} / V_ {100Z}) is strictly less than 1, preferably between 0.95 and 0.4.

Stage (d)

Catalytic hydrodeparaffination (HDPC)

The fraction that contains the compounds that boil above 340 ° C, as defined above, from the second stage and atmospheric distillation (c) it is then subjected, at least in part and preferably in its whole, to a stage of catalytic dewaxing in the presence of hydrogen and a hydrodeparaffination catalyst that carries a acidic function and a metallic function hydro-dehydrogenating and at least An array.

Note that the compounds that boil by above 340ºC they are always subjected to dewaxing catalytic

Acid function is ensured by at least one molecular sieve whose microporous system has at least one type main of channels whose openings are formed by rings that they contain 10 or 9 T atoms. T atoms are tetrahedral atoms constitutive of the molecular sieve and can be at least one of the  elements contained in the following set of atoms (Si, Al, P, B, Ti, Fe, Ga). In the constituent rings of the openings of channels, the T atoms, defined above, alternate with an equal number of oxygen atoms. It is therefore equivalent to say that the openings they consist of rings that contain 10 or 9 oxygen atoms or which are formed by rings containing 10 or 9 T atoms.

The molecular sieve that enters the composition of the hydrodeparaffination catalyst can also carry other types of channels, but whose openings are formed by rings containing less than 10 T atoms or oxygen atoms.

The molecular sieve that enters the composition The catalyst also has a bridge width, distance between two pore openings, as defined above, that it is at most 0.75 nm (1 nm = 10-9 m), preferably between 0.50 nm and 0.75 nm, even more preferably between 0.52 nm and 0.73 nm.

The applicant has discovered, in effect, that one of the determining factors for obtaining good catalytic yields in the third stage (stage of hydrodeparaffination) is the use of molecular sieves that they have a bridge width of at most 0.75 mm, preferably between 0.50 nm and 0.75 nm, preferably between 0.52 nm and 0.73 nm.

The measurement of the bridge width is performed using a spelling and molecular modeling tool, such as Hyperchem or Biosym, which allows you to build the surface of the molecular sieves in question and, taking into account the radii ionic elements present in the sieve frame, measure the bridge width

The catalyst that is suitable for this procedure is characterized by a catalytic test called standard n-dean transformation test pure, which is performed under a partial pressure of 450 kPa of hydrogen and a partial pressure of n-C 10 of 1.2 kPa, that is, a total pressure of 451.2 kPa in a fixed bed and with a constant n-C 10 flow rate of 9.5 ml / h, a total flow of 3.6 l / h and a catalyst mass of 0.2 g. The reaction is carried out in descending flow. Conversion rate It is regulated by the temperature at which the reaction. The catalyst subjected to said test is constituted by pure zeolite in pill and by 0.5% by weight of platinum.

The n-dean in the presence of the molecular sieve and one function hydro-dehydrogenating will suffer reactions of hydroisomerization that will produce isomerized products of 10 carbon atoms and hydrofisuration reactions that lead to formation of products containing less than 10 carbon atoms. Under these conditions, a molecular sieve used in the stage of hydrodeparaffination according to the invention must present the physicochemical characteristics described above and give rise, for a performance in isomerized products of n-C 10 of the order of 5% by weight (the rate of conversion is regulated by temperature), at a reason 2-methylnonano / 5-methyltilano superior to 5 and preferably greater than 7.

The use of molecular sieves as well selected, under the conditions described above, among the numerous already existing molecular sieves, especially allows The production of low pour and high flow products viscosity index with good yields under the procedure according to the invention.

Molecular sieves that can enter the Catalytic hydrodeparaffination catalyst composition are, by way of examples, the following zeolites: Ferrierite, NU-10, EU-13, EU-1 and Zeolites of the same structural type.

Preferably, molecular sieves that enter the composition of the hydrodewaxing catalyst they are included in the set formed by the ferrierite and the EU-1 zeolite.

The weight content in molecular sieve in the hydrodeparaffination catalyst is between 1 and 90%, preferably between 5 and 90% and even more preferred between 10 and 85%.

The matrices used to perform the laying in the form of the catalyst they are by way of examples and not limiting alumina gels, aluminas, magnesia, amorphous silica-aluminas and mixtures thereof. Can be use techniques such as extrusion, production of pills or dragee production to perform the operation of fit.

The catalyst also has a function hydro-dehydrogenating assured, for example, by the at least one element of group VIII and preferably at least one element included within the set formed by platinum and Palladium The non-noble metal weight content of group VIII with respect to the final catalyst is between 1 and 40%, preferably between 10 and 30%. In this case, the metal does not noble is frequently associated with at least one metal of the VIB group (Mo and W preferably). If it's at least one noble metal of group VIII, the weight content with respect to the catalyst final is less than 5%, preferably less than 3% and so even more preferred less than 1.5%.

In the case of the use of noble metals Group VIII, platinum and / or palladium are located preferably on the matrix, defined as before.

The hydrodeparaffination catalyst according to the invention may also contain from 0 to 20%, preferably from 0 to 10%, by weight (expressed in oxides) of phosphorus. The combination of metal (s) of group VI B and / or of Group VIII metal (s) with phosphorus is particularly advantageous

The hydrocracking residue (i.e. fraction with initial boiling point higher than 340 ° C) obtained in step (c) of the process according to the invention and to be try at this stage (d) of hydrodeparaffination possesses the following features: presents an initial boiling point greater than 340 ° C and preferably greater than 370 ° C, a point of fluidity of at least 15 ° C, a nitrogen content of less than 10 ppm by weight, a sulfur content below 50 ppm or better at 10 ppm by weight, a viscosity index of 35 to 165 (before the dewaxing), preferably at least equal to 110 and so even more preferred less than 150, a compound content aromatics less than 10% by weight and a viscosity at 100 ° C higher or equal to 3 cSt (mm2 / s).

These characteristics are also those of residue to be obtained by atmospheric distillation of a sample of a liquid fraction containing the compounds with point of boiling above 340 ° C, said fraction having a point of initial boiling less than or equal to 340 ° C and being subjected to catalytic dewaxing.

The operating conditions in which it operates the hydrodeparaffination step of the process of the invention They are as follows:

-

the reaction temperature is between 200 and 500 ° C and preferably between 250 and 470 ° C, advantageously between 270 and 430 ° C;

-

the pressure is between 0.1 and 25 MPa (10 6 Pa) and preferably between 1.0 and 20 MPa;

-

the hourly volumetric speed (vvh expressed in load volume injected per unit volume of catalyst and per hour) is between about 0.05 and about 50 and preferably between about 0.1 and about 20 h <-1>, and even more preferably between 0.2 and 10 h -1;

They are selected to obtain the point of Fluency sought.

The contact between the load entering dewaxing and the catalyst is performed in the presence of hydrogen. The rate of hydrogen used and expressed in liters of hydrogen per liter of charge is between 50 and approximately 2,000 liters of hydrogen per liter of charge and preferably between 100 and 1,500 liters of hydrogen per liter of load.

The person skilled in the art knows that the improvement of the pour point of the bases for oils, already obtain by solvent dewaxing procedure (DPS) or by a catalytic hydrodeparaffination procedure (HDPC), causes a decrease in the viscosity index (VI).

One of the characteristics of the procedure according to the invention is that:

-

the VI variation in the catalytic hydrodeparaffination stage (HDPC) is preferably greater than or equal to 0 for the same point of fluidity,

or

-

when a decrease in LV is observed in the stage of catalytic hydrodeparaffination (HDPC), this drop is weaker than which can be observed in the case of dewaxing with solvent (DPS) to obtain the same pour point. So, the ratio between the variation of VI of the oil base at the stage of catalytic dewaxing and the variation of VI of the base of oil in the dewaxing stage with solvent, \ DeltaVI_ {HDPC} / \ DeltaVI_ {DPS} is strictly less than 1 for the same pour point.

Stage (and)

Hydro Finish (Hydro Finish)

The effluent at the exit of the stage of Catalytic hydrodeparaffination is sent, in its entirety and without intermediate distillation, to a hydro-finishing catalyst in presence of hydrogen to perform a driven hydrogenation of aromatic compounds that impair the stability of oils and distillates. However, the acidity of the catalyst must be low enough not to lead to training of a boiling point cracking product less than 340 ° C so as not to degrade the final yields especially in oils

The catalyst used in this stage leads to at least one metal of group VIII and / or at least one element of the group VIB of the periodic classification. The strong metallic functions: platinum and / or palladium, or combinations of nickel-tungsten or nickel-molybdenum they will be advantageously used to carry out hydrogenation Aromatic driven.

These metals are deposited and dispersed on an amorphous or crystalline oxide type support, such as, for example, aluminas, silicas and silica-aluminas.

The hydro-finishing catalyst ("HDF") it may also contain at least one element of group VII A of the Periodic clasification of the elements. Preferably, these Catalysts contain fluorine and / or chlorine.

The weight contents in metals are between 10 and 30% in the case of non-metals noble and are less than 2%, preferably between the 0.1 and 1.5% and even more preferably between 0.1 and 1.0% in the case of noble metals.

The total amount of halogen is comprised between 0.02 and 30% by weight, advantageously between 0.01 and 15% or even between 0.01 and 10%, preferably between 0.01 and 5%.

They can be cited among the catalysts usable at this stage of HDF and that lead to excellent yields, and especially for obtaining oils medicinal, catalysts that contain at least one metal noble of group VIII (platinum, for example) and at least one halogen (chlorine and / or fluorine), the combination of chlorine and fluorine.

The operating conditions under which carries out the hydro-finishing stage of the procedure of the invention are as follows:

-

the reaction temperature is between 180 and 400 ° C and preferably between 210 and 350 ° C, advantageously between 230 and 320 ° C;

-

the pressure is between 0.1 and 25 MPa (10 6 Pa) and preferably between 1.0 and 20 MPa;

-

the hourly volumetric speed (vvh expressed in load volume injected per unit volume of catalyst and per hour) is between about 0.05 and about 100 and preferably between about 0.1 and about 30 h -1.

The contact between the charge and the catalyst is performed in the presence of hydrogen. The rate of hydrogen used and expressed in liters of hydrogen per liter of charge is comprised between 50 and approximately 2,000 liters of hydrogen per liter of load and preferably between 100 and 1,500 liters of hydrogen per liter of cargo

One of the characteristics of the procedure according to the invention is that the temperature of the HDF stage is below the temperature of the hydrodewaxing stage catalytic (HDPC). The difference T_ {HDPC} -T_ {HDF} is generally comprised between 20 and 200 and preferably between 30 and 100 ° C.

The effluent output from the HDF stage is sent to the distillation train, which integrates a distillation atmospheric and vacuum distillation and which aims separate lower boiling point conversion products at 340 ° C and preferably below 370 ° C (and including especially those formed in the hydrodeparaffination stage catalytic (HDPC)) of the fraction that constitutes the oil base and whose initial boiling point is higher than 340ºC and preferably higher than 370 ° C.

In addition, this vacuum distillation section allows to separate the different grades of oils.

The base oils obtained according to this procedure have a pour point below -10 ° C, a weight content in aromatic compounds less than 2%, a VI greater than 95, preferably greater than 110 and even more preferably greater than 120, a viscosity of at least 3.0 cSt at 100 ° C, an ASTM color less than 1 and such UV stability that the ASTM color increase is between 0 and 4 and preferably between 0.5 and 2.5.

The UV stability test, adapted from ASTM D925-55 procedures and D1148-55, provides a quick method to compare the stability of lubrication oils exposed to A source of ultraviolet rays. The test chamber is constituted by a metal enclosure equipped with a tray swivel that receives oil samples. A light bulb that produces the same ultraviolet rays as those of sunlight and which is located on top of the test chamber is directed towards Down on the samples. Samples include an oil standard with U.V. known. ASTM D1500 color from The samples is determined at t = 0 and then after 45 h of exposure at 55 ° C. The results are transcribed for the sample Standard and test samples as follows:

to)

color ASTM D1500 initial,

b)

color ASTM D1500 final,

C)

color increase,

d)

disturbance,

and)

precipitate.

Another advantage of the procedure according to the invention is that it is possible to expect aromatic contents very low, less than 2% by weight, preferably 1% by weight and better than 0.05% by weight, and even go to production of medicinal grade white oils that have contents in aromatics less than 0.01% by weight. These oils have UV absorbance values at 275, 295 and 300 nanometers, respectively, less than 0.8, 0.4 and 0.3 (ASTM D2008 method) and a Saybolt color between 0 and 30.

In a particularly interesting way, then, the process according to the invention also allows to obtain oils Medicinal whites Medicinal white oils are oils minerals obtained by a refined petroleum driven, its Quality is subject to different regulations that are intended guarantee its safety for pharmaceutical applications, they are devoid of toxicity and are characterized by their density and their viscosity. White medicinal oils essentially include saturated hydrocarbons, are chemically inert and their content in aromatic hydrocarbons is low. Particular attention is given to aromatic compounds and especially 6 hydrocarbons polycyclic aromatics (P.A.H. for the Anglo-Saxon abbreviation of polycyclic aromatic hydrocarbons), which are toxic and are present at concentrations of one part per billion by weight of aromatic compounds in white oil. The control of Total aromatic content can be done by the method ASTM D 2008; this UV adsorption test at 275, 292 and 300 nanometers allows to control a lower absorbance, respectively, at 0.8, 0.4 and 0.3 (that is, white oils have contents in aromatics less than 0.01% by weight). These measures are made with concentrations of 1 g of oil per liter in a 1 cm tank. The white oils marketed differ by its viscosity, but also because of its gross origin, which can be paraffinic or naphthenic; these two parameters are going to induce differences at the same time in the physicochemical properties of considered white oils and also in their composition chemistry.

Currently, oil fractions, already come from the direct distillation of a crude oil followed by an extraction of the aromatic compounds by a solvent, since come from a catalytic hydrorefining process or from hydrofisuration, they still contain non-negligible amounts of aromatic compounds In the current legislative framework of the majority from industrialized countries, white oils called medicinal products must have an aromatic content of less than one threshold imposed by the legislation of each of the countries. The absence of these aromatic compounds in the oil fractions it is translated by a Saybolt color specification that must be substantially at least 30 (+30), a maximum specification of UV adsorption that should be less than 1.60 at 275 nm on a pure product in cuba of 1 centimeter and a maximum specification of absorption of DMSO extraction products that must be less than 0.1 for the American market (Food and Drug Administration, norm nº 1211145). This last test consists of specifically extract polycyclic aromatic hydrocarbons with help of a polar solvent, often the DMSO, and in controlling its content in the extract by measuring the UV absorption in the 260-350 nm spectrum.

The average distillates obtained have points of improved fluidity (less than or equal to -20ºC), contained in low aromatics (at most 2% by weight), contained in polyaromatic (di and more) less than 1% by weight and for diesel with a cetane number greater than 50 and even greater than 52

Another advantage of the procedure according to the invention is that the total pressure can be the same in all reactors, hence the possibility of working in series and using a single unit and, therefore, to generate cost savings.

The procedure is illustrated in Figures 1 and 2, FIG. 1 depicting the treatment of the entire liquid fraction in hydrodeparaffination and figure 2 that of a hydrocracking residue.

In figure 1, the load enters the duct (1) in a hydrotreatment zone (2) (which may be composed by one or several reactors and comprises one or several beds catalysts of one or more catalysts), where hydrogen enters (for example through the duct (3)) and where stage (a) of hydrotreatment

The hydrotreated load is transferred by the conduit (4) to the hydrofissuring zone (5) (which may be composed of one or several reactors and comprises one or several beds catalysts of one or more catalysts), where it is carried out, in presence of hydrogen, stage (b) of hydrofisuration.

The effluent from zone (5) is sent through a conduit (6) to a flask (7) for the separation of the hydrogen, which is extracted through a conduit (8), and the effluent is then distilled at atmospheric pressure in column (9), of the that the gaseous fraction is extracted in the head (10). Be thus perform step (c) of the procedure.

You get at the bottom of the column a liquid fraction containing boiling compounds higher than 340 ° C. This fraction is evacuated through the duct (11) towards the zone (12) of catalytic dewaxing.

The catalytic dewaxing zone (12) (which it carries one or several reactors and one or several catalytic beds of one or more catalysts) also receives hydrogen by a conduit (13) to perform step (d) of the procedure.

The effluent that leaves this area for a conduit (14) is sent directly to the hydro-finishing zone (15)  (which carries one or several reactors and one or several catalytic beds of one or several catalysts), from where it comes out again by a duct (16). Hydrogen can be added if necessary to the area (15), where stage (e) of the procedure is carried out.

The effluent obtained is separated in a train of distillation (step f of the procedure) that also carries the flask (17) to separate hydrogen by a conduit (18), a column of atmospheric distillation (19) and a vacuum column (20) that deals the atmospheric distillation residue transferred through the duct (21), initial boiling point residue greater than 340 ° C.

They are obtained as products of distillations a fraction of oil (conduit 22) and fractions that boil more low, such as diesel (conduit 23), kerosene (conduit 24) and gasoline (duct 25); light gases are eliminated by the duct (26) of the atmospheric column and the gases are removed by the vacuum distillation column (27).

To not reload the figure, it has not represented the recycling of hydrogen, either at the level of the flask (7) towards hydrotreatment and / or hydrofisuration and / or level from the flask (17) towards dewaxing and / or hydro-finishing.

The marks of the Figure 1. The difference is at the distillation level of the effluent from the hydrofisuration stage (b) that exits through the duct (6). It separates, after separation of the hydrogen in the flask (7), by an atmospheric distillation in a column (9) of the gases that they are removed through the duct (10). Distillation is conducted to obtain a residue with an initial boiling point higher than 340 ° C that goes out through the pipeline (11) and to obtain the fractions of diesel (duct 28), kerosene (duct 29) and gasoline (channel 30).

Only waste in zone (12) of dewaxing

The recycles described below are fully transposable.

The assembly of conversion with 2 reactors without recycling of the effluent that leaves the hydrocracker (5).

It is also possible to recycle a part of this effluent towards the hydrotreatment stage carried out in the zone (2) and / or towards the hydrofisuration stage carried out in the zone (5).

The executor will adapt the recycling rate to his "products" objective to favor the obtaining of oils or rather that of middle distillates.

It is also frequent that the areas of hydrotreatment and hydrofisuration are in it reactor. From there, the transfer of the hydrotreated effluent is does directly in the absence of conduit (4). A recycling of effluent is always possible, either towards the area of hydrotreatment (upstream of a catalyst bed), already be towards the hydrofisuration zone.

In another embodiment of this stage of conversion (two-stage hydrofissuring), the residue that comes out of the duct (11) and presenting an initial boiling point higher than 340 ° C (as shown in figure 2) is sent, at least in part, to a supplementary zone (32) of hydrofisuration different from zone (5) (which carries one or several reactors and one or several catalytic beds of one or more catalysts). This other hydrocracking zone may contain the same catalyst as the zone (5) or other catalyst.

The resulting effluent is recycled to the atmospheric distillation stage.

The other part of the boiling point residue initial higher than 340 ° C is transferred to the stage of catalytic dewaxing.

In figure 3, these have been schematized possible modalities of the conversion assembly taking up the marks common with figure 2 and will not be described again.

The residue that leaves column (9) by conduit (11) is sent to the other hydrofissuring zone (32),  where an effluent comes out again in a pipe (33), which It is recycled in column (9). Through a duct (34) branched over the duct (11) leaves the residue, which is sent to the zone (12) of dewaxed.

It has also been shown in Figure 3 the realization in the same reactor (31) of the zones (2) of hydrotreatment and (5) hydrofisuration, but they are totally possible separate areas in combination with the supplementary zone (32) hydrofisuration.

The conversion assembly of Figure 3 can thus replace the conversion assembly of figure 2, the hydrodeparaffination stages remain unchanged and hydro-finished and distillation train. All possibilities Complementary (recycling H2 ...) are transposable.

In another variant of figures 2 or 3, the waste coming out of the pipeline (11) is sent to the unit of extraction of aromatic compounds (35), equipped with a conduit (36) for solvent inlet, of a conduit (37) for the exit of the solvent and a conduit (38) through which it exits the refining, which is sent to the catalytic dewaxing zone (12).

This variant (corresponding to stage (c ') of the procedure) is shown in figure 4. The treatments upstream and downstream are those of the procedure, such as, for example, those illustrated in figures 2 or 3.

Thus, the invention also relates to an installation for the production of high quality oils and possibly of high quality medium distillates, which carries:

\ lozenge

at least one area of hydrotreatment (2) containing at least one catalyst of hydrotreatment and that is equipped with at least one duct (1) for the introduction of the load and of at least one conduit (3) for the introduction of hydrogen;

\ lozenge

at least one area of hydrocracking (5) containing at least one catalyst of hydrocracking to treat the hydrotreated effluent from zone (2), leaving the hydrofissured effluent from zone (5) by the duct (6);

\ lozenge

at least one column of atmospheric distillation (9) to treat the hydrofissured effluent and which is equipped with at least one conduit (10) for the output of the gas fraction, of at least one conduit (11) for the exit of a liquid fraction (residue) containing the knitted compounds boiling above 340ºC and at least one duct (28, 29 or 30) for the output of at least one distillate;

\ lozenge

at least one unit of extraction of aromatic compounds (35) to treat the residue, equipped with at least one conduit (35) for carrying the solvent, from at less a conduit (36) for its exit and at least one conduit (38) for the output of the refining;

\ lozenge

at least one area of catalytic dewaxing (12) containing at least one catalyst dewaxing, where refining enters, and hydrogen is admitted by at least one conduit (13), the area (12) of at minus a conduit (14) for effluent outlet dewaxed;

       \ newpage
    

\ lozenge

at least one area of hydro-finished (15) to treat the effluent dewaxed by a hydro-finishing catalyst, leaving the effluent for at least one duct (16);

\ lozenge

at least one area of distillation comprising at least one distillation column atmospheric (19) and at least one vacuum distillation column (20), the column (19) being equipped with at least one conduit (26) for light gas outlet, at least one duct (23, 24 or 25) for the exit of at least one distillate and at least one duct (21) to recover a residue, carrying column (20) at least one conduit (22) for the output of the oil fraction and at least one conduit (27) for the output of the other compounds.

In another embodiment, the invention is relates to an installation in which zones (2) and (3) are located in the same reactor equipped with at least one conduit (1) for the entrance of the load, of at least one conduit (3) for the hydrogen inlet and at least one conduit (6) for the outlet of the hydrofissured effluent, taking said installation in addition to minus a supplementary hydrofisuration zone (32) equipped with at less a conduit (11) for the admission of the residue from the atmospheric distillation column (9) and at least one duct (33) for the discharge of the effluent thus hydrofisured, leading to said conduit (33) in conduit (6) to recycle said effluent, and the installation also has at least one conduit (34) located on the conduit (11) to transfer the waste to the unit of extraction (35).

Example 1

The hydrocracking residue is obtained by Hydrofisuration of a vacuum distillate whose composition is given in the Table 1.

In a reactor that contains a bed of amorphous catalyst (15% MoO3, 5% NiO, 80% alumina), is  enter the charge described in table 1 and hydrogen under a pressure of 14 MPa and in a volumetric ratio H 2 / HC = 1,000 Ni / Ni. The spatial velocity is then 0.75 h -1 over the amorphous catalyst The reaction temperature is 380 ° C.

It is loaded into a second reactor located after of this first reactor a catalyst 12% MoO3, 4% NiO and 20% zeolite Y on alumina. The product is introduced from the first reactor in the second reactor. The pressure is of 14 MPa and the product circulates at a spatial speed of 1.5 h -1. The effluent is recovered and then distilled under vacuum. The Characteristics of the 375 ° C + residue are given in Table 1.

Example 2

The residue is then introduced 375 ° C + obtained in example 1 in a reactor containing a bed of hydrodeparaffination catalyst (0.5% Pt and 80% ferrierite, the remainder being Al 2 O 3) and hydrogen under a pressure of 14 MPa and in a volumetric ratio H2 / HC = 1,000 Ni / Ni. The spatial velocity is then 1 h -1 on this catalyst. The reaction temperature is 315 ° C.

It is loaded into a second reactor located after of this first reactor a catalyst containing 1% by weight of Pt and 1% by weight of Cl on alumina. The product from first reactor is introduced into the second reactor, which is maintained at a temperature of 220 ° C. The pressure is 14 MPa and the product circulates at a spatial velocity of 0.5 h -1. Be The effluent is recovered and then distilled under vacuum. The Characteristics of the 375 ° C + residue are given in Table 1.

The test of carbonizable materials on the dewaxed and hydro-finished residue produced in example 2 obeys the norm in force.

In addition, UV absorption at 275 nm on product pure, in a 1 cm cuvette, it is 1.2, therefore less than rule.

Therefore, the dewaxed residue e hydro-finishing produced in example 2 constitutes an oil medicinal.

TABLE 1

Example 1 Example 2 Load Residue of Residue from hydrocracking hydrocracking dewaxed and hydro-finished 1st Catalyst (temperature / 380 ° C 315 ° C from reaction) 2nd Catalyst (temperature / 380 ° C 220 ° C from reaction) Conversion (% weight) / 80 Material balance / (% weight of load) (% by weight of the residue (% in weight) hydrocracking) H 2 S + NH 3 /  \ hskip0.3cm 3.26  \ hskip0.3cm 0.00 C1-C4 /  \ hskip0.3cm 1.70  \ hskip0.1cm 12.15 C5-150 /  \ hskip0.1cm 28.00  \ hskip0.3cm 7.80 150-380 /  \ hskip0.1cm 49.07  \ hskip0.3cm 5.90 375+ 100  \ hskip0.1cm 20.47  \ hskip0.1cm 75.20 Total 100 102.50 101.05 Residue 375ºC + load d15 / 4 0.9377 0.8415 / V @ 100ºC (mm2 / s) 11.15 5,525 / Sulfur (ppm weight) 29,600 6 / Nitrogen (ppm weight) 1,170 3 / ASTM D1500 color / 2.5 / Pour point (ºC) +39 +35 / Residue 375 ° C + Dewaxed Dewaxed Dewaxed and dewaxed with solvent with solvent hydro-finished catalytically d15 / 4 0.9479 0.8408 0.8413 V @ 40ºC (mm2 / s) 181 29.98 35.45 V @ 100ºC (mm2 / s) 12.87 5.67 6.28 SAW 44 132 127 Pour point (ºC) -twenty-one -18 -18 Saybolt color / / +30

TABLE 1 (continued)

Example 1 Example 2 Load Residue of Residue from hydrocracking hydrocracking dewaxed and hydro-finished UV absorption (D2008) / 260-280 nm / / 0.0008 280-290 nm / / 0.0007 290-300 nm / / 0.0003 300-360 nm / / 0.0002 360-400 nm / / <0.0001 300-300 nm / / 0.0002 330-350 nm / / <0.0001

Claims (19)

1. Procedure for the production of oils and of high quality medium distillates from a load hydrocarbon, at least 20% volume of which boils above 340 ° C, a procedure consisting successively of the following stages:

(to)

hydrotreatment performed at a temperature of 330-450 ° C under a pressure of 5-25 Mpa, with a spatial velocity of 0.1-6 h -1, in the presence of hydrogen in a volumetric ratio of hydrogen / hydrocarbon of 100-2,000 and in the presence of an amorphous catalyst consisting of at least one metal of group VIII and at least one metal from group VI B;

(b)

hydrofissuring, without separation intermediate of the effluent obtained from hydrotreatment, being Hydrofissuring performed at a temperature of 340-430 ° C under a pressure of 5-25 Mpa, with a spatial velocity of 0.1-5 h -1, in the presence of hydrogen and in the presence of a catalyst that it contains at least one zeolite and which also contains at least one element of group VIII and at least one element of group VI B;

(C)

atmospheric distillation without vacuum distillation of the effluent obtained from the hydrofisuration for separate the gases from the liquid;

(d)

catalytic dewaxing of at least a liquid fraction obtained by atmospheric distillation and that contains boiling point compounds higher than 340 ° C, dewaxing at a temperature of 200-500ºC low a total pressure of 1-25 Mpa, with a speed hourly volume of 0.05-50 h <-1>, with 50-2,000 l of hydrogen / l load, in the presence of a catalyst that also includes at least one element with hydro-dehydrogenating function and at least one screen molecular whose microporous system has at least one type main of channels with pore openings that have 9 or 10 atoms T, where T is selected from the group consisting of Si / Al, P, B, Ti, Fe and Ga, alternating with an equal number of oxygen atoms, being the distance between two accessible pore openings of 9 or 10 T atoms of at most 0.75 nm and presenting said sieve in the test of the n-dean a reason 2-methylnonano / 5-methyltilano superior to 5;

(and)

be subject the dewaxed effluent directly to a treatment of hydro-finishing done at a temperature of 180-400 ° C, which is lower than the temperature of the catalytic dewaxing at least 20 ° C and at most 200 ° C, under a total pressure of 1-25 Mpa, with a hourly volumetric speed of 0.05-100 h -1, in presence of 50-2,000 liters of hydrogen / liter of loading and in the presence of an amorphous catalyst for hydrogenation of the aromatics, which includes at least one metal selected from the group of group VIII metals and group VI metals B;

(F)

be subject the effluent from the hydro-finishing treatment to a distillation stage consisting of an atmospheric distillation and a vacuum distillation to separate at least a fraction of oil of a boiling point higher than 340 ° C and presenting a point of fluidity below -10 ° C, a weight content of compounds aromatic less than 2% and a VI greater than 95 and a viscosity at 100 ° C of at least 3 cSt (that is, 3 mm 2 / s), and to separate possibly at least a fraction of medium distillate that has a pour point of less than or equal to -20 ° C, a content of aromatics of at most 2% by weight and a content of Polyaromatic at most 1% by weight.

2. Method according to claim 1, where the molecular sieve of the dewaxing stage (d) is selected from the group formed by zeolites ferrierite, NU-10, EU-1 and EU-13. 3. Procedure according to one of the preceding claims, wherein the catalyst of dewaxing stage (d), the element with function hydro-de-hydrogenating, is selected from the group consisting of the elements of group VIII and the elements of group VI B, said catalyst also containing match. 4. Procedure according to one of the preceding claims, wherein the function element Hydrogenating in step (d) is palladium and / or platinum. 5. Procedure according to one of the preceding claims, wherein the catalyst of step (d) includes at least one subject selected from the group formed by alumina gels, aluminas, magnesia and amorphous silica-aluminas. 6. Procedure according to one of the preceding claims, wherein the function element hydrogenating stage (d) is a noble metal of group VIII located on the matrix. 7. Procedure according to one of the preceding claims, wherein the variation of the VI in the stage dewaxing (d) is greater than or equal to 0 for the same point of fluency, or, when a decrease in LV is observed, the reason between the variation of VI in step (d) and the variation of VI in a solvent dewaxing stage, called \ DeltaVI_ {HDPC} / \ DeltaVI_ {DPS}, is strictly less than 1 for the same pour point. 8. Procedure according to one of the preceding claims, wherein the hydrocracking residue obtained in stage (c) and to be treated in stage (d) it has a nitrogen content of less than 10 ppm by weight, a sulfur content less than 10 ppm by weight, an index of viscosity of at least 110, a content of aromatic compounds less than 10% by weight, a viscosity at 100 ° C greater than or equal to 3 mm2 / s and an initial boiling point greater than 370 ° C. 9. Procedure according to one of the preceding claims, wherein the hydro-finishing catalyst of stage (e) carries an amorphous support, at least one noble element Group VIII, chlorine and fluorine. 10. Procedure according to one of the preceding claims, wherein the steps (a) of hydrotreatment and (b) hydrofisuration are performed therein reactor. 11. Procedure according to one of the claims 1 to 9, wherein the steps (a) of hydrotreatment and (b) Hydrofissuring are performed in different reactors. 12. Procedure according to one of the preceding claims, wherein in the distillation stage (c) atmospheric an initial boiling point residue is obtained higher than 340 ° C and then undergoes catalytic dewaxing of stage (d). 13. Method according to claim 12, where the hydrocracking residue is recycled at least in part to the hydrotreatment stage and / or the hydrofisuration stage. 14. Method according to claim 12, where at least one part of the hydrofisuration residue undergoes a Complementary hydrofisuration stage different from stage (b), the effluent obtained being recycled to step (c) of atmospheric distillation and the other part of the waste being treated in stage (d) dewaxing. 15. Procedure according to one of the claims 12 to 14, wherein the residue from the Atmospheric distillation of stage (c) is subjected to extraction of the aromatic compounds (step c ') and the refining obtained is catalytically dewaxed in step (d). 16. Procedure according to one of the preceding claims for the production of white oils which have aromatic contents of less than 0.01% by weight. 17. Procedure according to one of the preceding claims, wherein in step (f) a medicinal oil that has a Saybolt color of substantially al minus 30, a maximum adsorption value U.V. less than 1.60 at 275 nm on a pure product in a 1 centimeter cuvette and a maximum value absorption of DMSO extraction products less than 0.1. 18. Installation for the production of oils from high quality and eventually high quality middle distillates that carries:

-

to the at least one hydrotreatment zone (2) that contains at least one hydrotreatment catalyst and that is equipped with at least one conduit (1) for the introduction of the load and of at least one conduit (3) for the introduction of hydrogen;

-

to the at least one hydrofissuring zone (5) containing at least one hydrocracking catalyst containing at least one zeolite, at at least one element of group VIII and at least one element of the group VIB, to treat the hydrotreated effluent from zone (2), the hydrofissured effluent leaving the area (5) through the duct (6);

-

to the minus one atmospheric distillation column (9) to treat the hydrofissured effluent and that is equipped with at least one duct (10) for the exit of the gas fraction, from at least one duct (11) for the output of a liquid fraction (residue) containing the boiling point compounds higher than 340 ° C and at least a conduit (28, 29 or 30) for the output of at least one distilled;

-

to the minus one extraction unit for aromatic compounds (35) to carry the solvent with at least one conduit (36) for its exit and at least one conduit (38) for the exit of the refining;

-

to the minus a catalytic dewaxing zone (12) that contains the less a catalytic dewaxing catalyst that includes the less an element with function hydro-dehydrogenating and at least a molecular sieve whose microporous system has at least one main type of channels with pore openings that have 9 or 10 T atoms, T being selected from the group consisting of Si / Al, P, B, Ti, Fe and Ga, alternating with an equal number of oxygen atoms, the distance between two pore openings accessible at 9 or 10 T atoms of at most 0.75 nm and presenting said sieve in the test of the n-dean a reason 2-methylnonano / 5-methylnonano greater than 5, where the refining enters, and hydrogen is admitted by the less a conduit (13), the zone (12) being equipped with at least one conduit (14) for the outlet of the dewaxed effluent;

-

to the minus a hydro-finishing zone (15) to treat the effluent dewaxed by a hydro-finishing catalyst, leaving the effluent through at least one duct (16);

-

to the at least one distillation zone comprising at least one column of atmospheric distillation (19) and at least one distillation column at vacuum (20), the column (19) being equipped with at least one duct (26) for the exit of light gases, at least one conduit (23, 24 or 25) for the output of at least one distillate and at least one conduit (21) to recover a residue, carrying column (20) to minus a conduit (22) for the output of the oil fraction and at less a conduit (27) for the output of the others compounds.

19. Installation according to claim 18, where zones (2) and (3) are located in the same reactor equipped with at least one conduit (1) for the load inlet, of at least one conduit (3) for the entry of hydrogen and at least a conduit (6) for the outlet of the hydrofissured effluent, carrying said installation in addition to at least one supplementary zone of hydrocracking (32) equipped with at least one conduit (11) for the admission of the residue from the distillation column atmospheric (9) and at least one conduit (33) for the exit of the effluent thus hydrofisured, said duct (33) flowing into the conduit (6) to recycle said effluent, and also the installation carries at least one conduit (34) located above the conduit (11) for transfer the residue to the extraction unit (35).