FR2680704A1 - Process for presulphurisation and for control of the activity of a catalyst for hydrocarbon processing - Google Patents

Abstract

Process for the two-stage treatment of a new or regenerated catalyst containing (a) a support based on at least one oxide of a metal or of a metalloid and (b) at least one active metal, in which process, in a first stage carried out "ex situ" approximately between 0 and 50@C and in the absence of hydrogen, the catalyst is treated with the aid of at least one sulphurising agent so as partially or completely to incorporate this agent in the porosity of the catalyst, the sulphurising agent being an organic polysulphide, in which process, next, in a second stage, the catalyst obtained in the first stage is treated by a method in which (a) the catalyst is treated, in the absence of hydrogen and in the presence of at least steam or of at least one moist inert gas "in situ" or "ex situ". The process is characterised in that during the first stage 0.1 to 10 % by weight of at least one halogen- or phosphorus-containing compound is added, the weight being expressed as halogen or as phosphorus, relative to the weight of polysulphide(s), the said agent being introduced in an anhydrous organic medium.

Description

The regeneration of catalysts used in refining, hydrorefining or petrochemicals is increasingly done in a catalyst regeneration specialist, sometimes far from the industrial unit. However, it seems reasonable to think of returning to the refiner a ready-to-use product, as permitted by the applicant's process (EP-B-181254) in which a sulfur compound is incorporated in the catalytic mass, which This compound causes the sulphurization or the presulphurization of the catalyst when, subsequently, in the reaction zone (charge treatment zone) or in the immediate vicinity of the reaction zone, the catalyst will be brought into contact with hydrogen, for example.

More precisely, in the European patent EP-B-181 254, the process for sulphurizing the catalyst is characterized by a preliminary stage known as incorporation into the catalytic mass of a sulfur compound of a particular nature.

The preliminary step of introduction of a sulphide compound, arbitrarily called "off-site" or "ex situ" pretreatment, whether carried out near the site of the industrial unit or at a greater or lesser distance geographically of the industrial unit (where the catalyst has been regenerated or where it has been manufactured for example) is no longer anyway in the immediate vicinity of the reactor (it is written arbitrarily "in situ") that is -describe at the head of the reactors or in zones more or less in direct communication with these reactors, requiring to operate under operating conditions (temperature, pressure or others), imposed at least partly by the operating conditions of the reactors themselves or annexes of these reactors (pre-hydrogenation zone of the catalyst for example).

The method of EP-B-181 254 allows, when the catalyst is subjected from its start preferably on the site ("in situ") to the conventional reaction of activation in the presence of hydrogen, (generally above 100 -C), then proceed, thanks to the presence of hydrogen on the site, to the sulphurization at the required stoichiometric or non-stoichiometric rate of the active metal (s) used in the composition of the catalyst.

The method comprises incorporating in a first step, in the absence of hydrogen, in the porosity of the new or regenerated catalyst at least one sulfurizing agent, the sulphiding agent being a polysulfide of the general formula R - S <n> -R.

Said sulphurizing agent is used in solution in a solvent.

In the second step, carried out "in situ", and preferably above 150.degree. C., a catalyst activation step is carried out in the presence of hydrogen, the required amount of sulfur being fixed thanks to the presence of hydrogen, on the metal or metals used in the composition of said catalyst.

In the polysulfide of formula
R - Sc n - R 'n is an integer from 3 to 20, preferably from 4 to 8 and more preferably from 5 to 7; R and R ', identical or different, represent organic radicals each containing 1 to 150 carbon atoms per molecule, preferably 10 to 60 carbon atoms or 5 to 40 carbon atoms and more particularly 7 to 16, these radicuax being selected from the group consisting of alkyl radicals, that is to say, saturated or unsaturated, linear or branched or naphthenic, aryl radicals, alkylaryl radicals and arylaryl radicals, these various radicals may comprise at least one hetero atom. R 'optionally may also be a hydrogen atom.

The first step mentioned above is carried out in the absence of hydrogen and makes it possible to obtain with a very high degree of precision the degree of total or partial sulphurization requested by the user.

The sulfurizing agent is used, diluted in a suitable solvent.

At the end of this first stage, we proceed to a second stage which is divided into two parts
The first part of this second stage is carried out in situ or ex situ. The first part of the second step is carried out in the absence of hydrogen. It is carried out in the presence of air or an inert gas.

According to a preferred method, it is carried out in the presence of at least water vapor or at least moist air or a wet inert gas for at least about 5 minutes, "in-situ" or "in-situ". ex-situ "at a temperature between 65 and 270 ° C under a pressure of between about 0.5 and 70 bar (0.05 and 7 MPa), the catalyst being then dried.

Subsequently, at the site or near the site (on which the catalyst will be used for the treatment of various fillers), during the conventional activation reaction, carried out in the presence of hydrogen (second stage of the patent application process) European EP-B181 254), the sulphurizing agent introduced into the catalyst in predetermined quantities, will be capable of giving rise to hydrogen sulphide which, in the presence of hydrogen, will lead to the desired sulphide or sulphides of the metal or metals present in the catalyst.

In the second step, the catalyst is heated to at least 275 ° C for at least 1 minute.

The second part of the second stage is generally carried out insitu and can thus be confused with the start or actual start of the refining and petrochemical reaction for which is designed the catalyst prepared according to the present invention, in the case precisely where such a reaction is made above 275 ° C.

When the temperature chosen for the refining or petrochemical reaction is less than 275 ° C. (for example, it may be the case for the hydrodesulfurations of gasolines or kerosenes), it is then sufficient to lower the temperature used for the reaction. activating the catalyst in the second part of the second step after this step at the temperature suitable for the refining or petrochemical reaction.

It has been found that in the first part of the second stage, in spite of the absence of hydrogen, the catalyst is sulphidized, that is to say that the oxides of the active metals of the catalyst are converted into sulphides. This phenomenon is easily observed by catalyst analysis, which also becomes black. On the other hand, chemisorption tests show that as long as the catalyst does not reach the temperature of 275 ° C. and does not remain for at least a few minutes at least 275 ° C., this catalyst remains devoid of catalytic activity.

The invention relates to the introduction of at least one additive based on a halogen or phosphorus during such a presulfiding method described above. The invention relates to an improvement described in
EP-A-349 358 of the applicant and is characterized in that the additive is added in a perfectly anhydrous medium.

The present invention relates to a method of introducing at least one additive based on a halogen or phosphorus during a two-stage treatment process of a new or regenerated catalyst containing (a) a carrier based on at least one oxide of a metal or a metalloid and (b) at least one active metal, a treatment process in which, in a first step carried out "ex-situ" between 0 and 50 ° C approximately and in the absence of hydrogen, the catalyst is treated with at least one sulphurizing agent so as to partially or totally incorporate this agent in the porosity of the catalyst, the sulphurizing agent being a polysulfide of general formula
R - S <n> - R '
The method of introducing additive being characterized in that during the first step, in a water-free atmosphere is added by weight (weight expressed as halogen or phosphorus), relative to the weight of polysulfide or polysulfides 0.1 to 10%, preferably 1 to 6% and more particularly 2 to 5% of at least one additive selected from the group consisting of phosphorus, phosphorus compounds, halogens and halogenated compounds, so as to add in the catalytic mass 0.05 to 20%, preferably 0.1 to 15% of halogen or phosphorus.

The invention is particularly suitable for hydrocarbon cracking and hydrocracking catalysts and more generally for hydrocarbon conversion reactions and for refining operations.

The method according to the invention implies that the first part of the first step is carried out in the presence of at least water vapor or at least a wet inert gas, especially moist air.

The additive (s) may be added, for example, with the solution of the polysulfide (s) used, either in the pure state or dissolved in a suitable anhydrous solvent. This solvent may be of the same type as the solvent chosen for dissolving the polysulfide, namely, for example a light gasoline boiling for example between about 60 to 95 ° C., a hexane type gasoline boiling between about 63 and 68 ° C. , - an essence of type F boiling between about 100 and 160 C and tale
generally 10 to 20% of aromatic hydrocarbons, for example
15% (by volume), - a type of essence "white spirit" boiling between about 150 and 250'C
and generally containing 14 to 22% aromatic hydrocarbons, by
Example 17%, by volume, - any hydrocarbon fraction or not, equivalent to the preceding species.

The halogenated and / or phosphorus-containing organic compound (s) according to the invention may be used in another suitable solvent such as, for example, anhydrous alcohols (methanol, ethanol, propanol, etc.) or other mineral liquids or organic solvents known to dissolve the selected additives and insofar as the chosen solvent is compatible with the other products or solvents used in the process and contains no trace of water.

 As halogenated or phosphorus additives, use will be made, for example, of those cited in EP-A-349,358 incorporated herein by reference.

EXAMPLES
In the following examples, we will study, for a hydrorefining of a hydrocarbon fraction, the incidence of the catalyst presulfidation method adopted, with the addition of halogenated and / or phosphorus compounds.

The cut proposed for hydrorefining is a model load containing, by weight, 20% of toluene 2% of thiophene 78% of cyclohexane
The operating conditions are as follows: Temperature: 350 ° C.
Total pressure: 60 bar (6 MPa)
VVH (space velocity): 2 liters charge / liter catalyst / hour
H2 / HC: Hydrogen / hydrocarbons: 350 l / h
Duration of treatment: 48 hours
Catalyst volume involved: 40 cc in all the examples.

The analysis of the effluents is carried out by gas chromatography. The hydrogenation ("A") activity of toluene and the isomerization ("I") activity of cyclohexane to methylcyclopentane will be measured in each test:
A = Log 1 1 - X (logarithm of Neperian) where X is the conversion rate of toluene, that is to say,

représentant la somne des titres molaires des produits de conversion du toluène (méthylcyclohexane, éthylcyclopentane et les diméthylcyclo- pentanes) et

représentant la

representing the molar titanium content of the toluene conversion products (methylcyclohexane, ethylcyclopentane and dimethylcyclopentanes) and

representing the

<tb><SEP> 7
<tb> s "Island
<tb> + residual toluene titer.

X is between 0 and 1, X being 1 for 100 X conversion of toluene.

I = 100 x molar title of methylcyclopentane
(Molar title in methylcyclopentane
+ molar ratio of residual cyclohexane) (the activity in isomerization I makes it possible to measure the acidity of the catalyst).

The catalyst used is a commercial catalyst of the company
Procatalyse HR 346 containing by weight 3% nickel oxide NiO and 14% Mo03 molybdenum oxide, these active metal compounds being deposited on an alumina. A commercial catalyst of the
Company PR0CATALYSE: HYC 642 containing oxides of nickel and molybdenum on a zeolitic support.

Other hydrocracking catalysts on zeolitic support such as HIY or S 5030 from SHELL CHEMICAL or HC 14, HC 16 or HG 22 from UNOCAL (catalysts based on nickel and molybdenum oxides or nickel and tungsten oxides) have been used in particular.

Example I: (comparative)
In this example, the catalyst is sulphurized according to the method of the European patent EP-B-181254 in two stages.
First stage
For the presulphurization of the catalyst, TPS 37 manufactured by
ELF AQUITAINE and containing about 37% by weight of sulfur, (the formula was given in the general part of this patent application); in order for all of the polysulfide to be adsorbed, a volume of reagent (polysulfide + polysulfide solvent) equal to the impregnation volume of the treated catalyst feed must be used. It is the knowledge of this total pore volume, or impregnation volume, which determines the amount of solvent to be used. In the context of the present test, this volume, per 100 g of catalyst, is 45 ml on average (of which 60% solvent and 40 X polysulfide). The solvent used is a White Spirit (boiling point between 150 and 250 ° C).

The sulfur stoichiometry necessary for the subsequent sulphurisation of all the oxides (NiO, MoO3) is used, ie 7.1 X S. The dry impregnation of the catalyst is followed, followed by evaporation under 10 mm of mercury ( 13,600 Pa) or under a stream of inert gas.

Second step
The catalyst is introduced into the reactor. The reactor is pressurized with a bar in the presence of air. (The same results would be obtained under a higher pressure, for example 60 bars). The catalyst is heated for 1 hour.

A Tc test is carried out at 150 ° C.

The catalyst becomes black, with deposition of water.

The SO 2 in the off-gases is measured using a COSMA brand infrared analyzer.

The sulfur content by weight in the catalyst after the test is the following% S = 5.95
The catalyst is then introduced into the hydrorefining reactor
The reactor is placed under a hydrogen atmosphere, cold. The pressure is raised to 60 bars and the temperature to 150 C.

The hydrorefining tests are carried out as follows: the charge to be converted is injected and then the temperature is raised to 300 ° C. for 1 hour and then to 350 ° C. for the test.

During the first part of the second stage, it is also not carried out in the presence of air but with a mixture of 5% by volume of air on the one hand and 95% by volume of water vapor initially superheated to 115 'C on the other hand (T'c test).

The results obtained are given in the table below

<tb>(<SEP>:<SEP> Tc <SEP>: <SEP>T'c
<tb>(<SEP>:<SEP>:<SEP>)<SEP>
<tb>(<SEP> A <SEP>: <SEP> 0.83 <SEP>: <SEP> 1.10
<tb> (-------- <SEP> ------ <SEP> -------)
<tb>(<SEP> I <SEP>: <SEP> 0.74 <SEP>: <SEP> 1.03 <SEP>)
<tb>(<SEP>:<SEP>:<SEP>)
<Tb>
Example 2 (according to the invention):
The procedure is as in Example 1. However, the first step is carried out here in the presence of halogenated and / or phosphorus additives.

3% by weight of halogen or phosphorus is used relative to the organic polysulfide.

Each of these additives is added in an anhydrous white spirit which serves as a solvent for the organic polysulfide.

The results of the tests T1c (corresponding to Tc in the comparative example) and T1'c (corresponding to T'c in the comparative example) are as follows:

<tb> Tic <SEP>T'ic
<tb> (- ::: :)
<tb> CH2 <SEP> F <SEP> COOH <SEP> 0.82 <SEP>: <SEP> 0.72 <SEP>: <SEP> 1.18 <SEP>: <SEP> 1.11
<tb>(<SEP> CH <SEP> Cl2 <SEP> COOH <SEP>: <SEP> 0.80 <SEP>: <SEP> 0.70 <SEP>: <SEP> 1.19 <SEP> 1 , 12 <SEP>)
<tb>(<SEP> CH2 <SEP> Cl <SEP> COOH <SEP> 0.81 <SEP> 0.72 <SEP> 1.18 <SEP> 1.11
<tb>(<SEP> CBr3 <SEP> COOH <SEP> 0.80 <SEP> 0.70 <SEP> 1.20 <SEP> 1.13
<tb>(<SEP> CH2 <SEP> Br <SEP> OOOH <SEP> 0.81 <SEP>: <SEP> 0.70 <SEP>: <SEP> 1.18 <SEP>: <SEP> 1 10
<tb>(<SEP> CH2 <SEP> I <SEP> COOH <SEP>: <SEP> 0.81 <SEP> 0.70 <SEP>: <SEP> 1.18 <SEP>: <SEP> 1 , 10 <SEP>)
<tb>(<SEP> C3 <SEP> F7 <SEP> COOH <SEP>: <SEP><SEP> 0.80 <SEP>: <SEP> 0.69 <SEP>: <SEP> 1.21 <SEP>:<SEP> 1.13
<tb>(<SEP> H3 <SEP> 104 <SEP>: <SEP><SEP> 0.78 <SEP>: <SEP> 0.62 <SEP>: <SEP> 1.18 <SEP>: <SEP> 1.08
<tb> H3 <SEP> 103 <SEP> 0.77 <SEP> 0.62 <SEP>: <SEP> 1.17 <SEP>: <SEP> 1.08
<tb>(<SEP> (NH4) <SEP> H2 <SEP> P04 <SEP>: <SEP> 0.75 <SEP>: <SEP> 0.64 <SEP>: <SEP> 1.15 <SEP > 1.07
<tb>(<SEP> (NH4) 2 <SEP> H <SEP> PO3 <SEP> 0.76 <SEP>: <SEP> 0.63 <SEP>: <SEP> 1.15 <SEP>: <SEP> 1.07
<tb>(<SEP> (NH4) <SEP> H2 <SEP> PO3 <SEP> 0.76 <SEP> 0.62 <SEP> 1.16 <SEP> 1.08 <SEP>)
<tb>(<SEP> (NH4) 2 <SEP> H <SEP> PO3 <SEP> 0.75 <SEP>: <SEP> 0.63 <SEP> 1.16 <SEP>: <SEP> 1, 07 <SEP>)
<tb>(<SEP> tri-p-tolylphosphine <SEP> 0.75 <SEP>: <SEP> 0.62 <SEP>: <SEP> 1.17 <SEP>: <SEP> 1.09
<tb>(<SEP> 50 <SEP>% <SEP><SEP> C3 <SEP> F <SEP> OOOH <SEP>:
<tb>(<SEP> 50 <SEP>% <SEP> p <SEP> tri-p- <SEP>: <SEP>:
<tb>(<SEP> tolylphosphine <SEP>: <SEP> 0.77 <SEP>: <SEP> 0.60 <SEP>: <SEP> 1.25 <SEP>: <SEP> 1.18
<Tb>
These results show, on the one hand, that the technique according to the invention is effective when the first part of the second stage is carried out in the presence of water, but on the other hand, that this same technique is bad when it is not operated in presence of water and even gives results slightly lower than those obtained in EP-B-181254.

Claims (6)

1. Method for introducing at least one additive based on a halogen or  of phosphorus during a two-step treatment process of a  new or regenerated catalyst containing (a) a carrier based on  minus an oxide of a metal or metalloid and (b) at least one metal  active, treatment method in which, in a first step  performed "ex-situ" between 0 and 50'C and in the absence  of hydrogen, the catalyst is treated with at least one  sulphurisation so as to partially or totally incorporate this  agent in the porosity of the catalyst, the sulfurizing agent being a  polysulfide of the general formula  R - S <n> - R '  where n is an integer from 3 to 20 and where R 'represents an atom of hy  or another radical identical or different from the radical R, these 2  radicals thus each representing an organic radical containing 1 to  150 carbon atoms per molecule, these radicals being chosen from  group consisting of alkyl radicals, i.e., saturated or  unsaturated linear or branched or naphthenic type, the radicals  aryls, alkylaryl radicals and arylalkyl radicals, the so-called  sulphurizing agent being used in solution in a solvent,  process in which then, in a second step, the  catalyst obtained in the first stage by a method in which  treats the catalyst, in the absence of hydrogen and in the presence of  less than water vapor or at least moist air or a gas  wet inert for at least about 5 minutes, "in-situ" or "ex  "at a temperature of between 65 and 275 ° C under a pressure  between about 0.5 and 70 bar (0.05 and 7 MPa), the catalyst  being at this point possibly dried, the process of introduction  additive being characterized in that during the first step,  in a non-humid atmosphere, we add by weight (weight expressed in  halogen or phosphorus), based on the weight of polysulphide or  polysulfides, 0.1 to 10% of at least one additive selected from the group  consisting of phosphorus, phosphorus compounds, halogens and  halogenated compounds to incorporate 0.05 to 20% halogen or  phosphorus (by weight) on the catalytic mass. 2. Method according to claim 1 wherein 1 to 6 X is used in  weight of said additive relative to the polysulfide used.  weight of said additive relative to the polysulfide used.  3. Process according to claim 1, in which 2-5% is used in 4. Process according to claim 1, in which at least one  additive containing a halogen and at least one additive containing  phosphorus, the total amount of additive used, by weight, and  expressed in halogen and phosphorus in relation to the weight of  polysulfide, being between 0.1 and 10 X. 5. Method according to one of claims 1 to 4 applied either to the  treatment of a new catalyst, prior to its use, either  applied to the treatment of a catalyst, prior to its use,  said catalyst having just been subjected to off-site regeneration. 6. Method according to one of claims 1 to 5 applied to  catalysts including hydrocracking, cracking and conversions  hydrocarbons.