KR920009117B1 - Porous solid phosphoric acid catalyst system and process using same - Google Patents

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Description

[Name of invention]

Porous solid phosphate catalyst system and its use method

Detailed description of the invention

The present invention relates to a porous solid phosphoric acid catalyst complex, which is characterized in that up to 25.0% of the total pore volume of the catalyst is composed of pores (pore) of more than 10,000mm in diameter.

Solid phosphoric acid is a name given to a calcination mixture of phosphoric acid with a porous binder such as kieselguhr, infusorial earth and diatomaceous earth. For many years practically, solid phosphate catalysts have been effective catalysts for the polymerization of common gas olefins to form common liquid hydrocarbons. Propane and propylene, butane and butylenes, and mixtures of ethane and ethylene are the main feedstocks for the polymerization process. Solid phosphoric acid catalysts are also very useful as catalysts in the process of alkylating aromatic hydrocarbons with aliphatic hydrocarbons, in particular in the process of alkylating benzene with propylene to produce cumene.

Solid phosphoric acid catalysts with certain properties, additives, and formulations are well known in the art as providing catalysts that are stronger, more active, and more effective. However, no solid phosphoric acid catalyst composite is known so far, characterized in that less than 25.0% of the total pore volume of the catalyst composite consists of pores with a diameter of 10000 mm 3 or more and exhibits improved stability in the catalyst condensation reaction.

The basics of solid phosphoric acid catalyst composites are well known in US Pat. No. 2,586,852, which describes, for example, solid phosphoric acid consisting of a mixture of kaolin, crystalline silica and phosphoric acid.

Porous binders have been known to improve the performance properties of solid phosphoric acid catalyst composites. U.S. Patent No. 3,044,964 describes a solid phosphate catalyst composite consisting of phosphoric acid and a naturally porous silica material. In addition, the catalyst may comprise a binder that is not naturally porous.

Due to the limited pore volume available, control over the stability of solid phosphate catalyst systems is relatively unknown in the art. U. S. Patent No. 3,661, 801 describes a solid phosphoric acid catalyst composite prepared to obtain a special pore volume distribution. However, in the catalyst disclosed in the above patent, pores having a diameter of 350 mm 3 or more have a pore volume of 0.2 to 0.4 cc / g and those having a diameter of 9000 mm or more have a pore volume of 0.07 to 0.20 cc / g. Therefore, the volume percentage of the catalyst pores of the conventional catalyst composed of pores having a diameter of 9000 kPa or more is 17.5% or more, or 0.07 cc / g in an absolute amount. It is also described that the catalyst is prepared by a method that yields only spherical catalysts. However, the catalyst of the present invention and the catalyst prepared by the method described in the above-mentioned US Pat. No. 3,661,801 are distinguished in all of these respects.

An important object of the present invention is to provide an improved porous solid phosphoric acid catalyst. The improved catalyst system exhibits improved stability over similar conventional catalysts. The improvement in stability is due to the unique pore volume distribution of the catalyst according to the invention.

Accordingly, a broad embodiment of the invention relates to a porous solid phosphoric acid catalyst system. The solid phosphoric acid catalyst composite consists of a complex of solid phosphoric acid and a binder. The catalyst is characterized in that less than 25.0% of the total pore volume of the catalyst composite consists of pores having a diameter of 10000 mm 3 or more. The solid phosphate catalyst composite is also characterized in that the binder is an inorganic oxide, more preferably a silica material (eg, diatomaceous earth, kisselgur, or artificial silica or mixtures thereof).

In a preferred embodiment, the porous solid phosphoric acid catalyst composition is in the form of an extrudate and consists of phosphoric acid and an inorganic oxide binder. Preferred catalysts comprise not more than 17.5% of the total pore volume of the catalyst composite extrudate consisting of pores of diameters greater than 10,000 mm 3. There is this. The catalyst is characterized in that the pore volume of the whole catalyst composite extrudate is about 0.28 cc / g or less, and the absolute pore volume in pores having a diameter of 10,000 mm 3 or more is 0.07 cc / g or less. Finally, the catalyst composite of the present invention preferably comprises at least 60% by weight of P ₂ O ₅ .

In another embodiment, the present invention relates to a process for converting hydrocarbons in the presence of the solid phosphoric acid catalyst by contacting the solid phosphoric acid catalyst complex and the hydrocarbon feedstock in hydrocarbon conversion conditions.

Solid phosphoric acid catalysts are known to be useful in many important hydrocarbon conversion processes. However, there have always been problems associated with the use of solid phosphoric acid catalysts in such processes, including catalyst dissolution, poor physical strength of the catalyst, poor stability of the catalyst and the like. Therefore, there has always been a need for strong catalysts that exhibit high activity and stability. To achieve the goal of producing strong, high activity and long lifetime catalysts, the pore volume is an important factor in the stability of solid phosphoric acid, and the reduction of the volume of macropores (ie, the volume of pores with diameters greater than 10,000 mm 3) is of great importance. Is now found.

An important aspect of the present invention is that up to 25% of the total pore volume of the catalyst consists of pores of diameters greater than 10,000 mm 3. Most preferably, less than 17.5% of the total pore volume of the catalyst consists of pores with a diameter of 10,000 mm 3 or more. A very high volume of macropores is believed to not only reduce the strength of the extrudate but also increase the carbon accumulation during use resulting from improved pore diffusion due to macroporosity. The larger the carbon accumulation during the reaction, the faster the catalyst deactivation and catalyst expansion can result in a larger pressure drop than the normal reactor pressure drop.

It has also been found that the total pore volume of the catalyst is proportional to the catalyst stability. Therefore, the total pore volume of the catalyst is preferably 0.28 cc / g or less, preferably 0.23 cc / g or less.

An essential active ingredient of the solid phosphoric acid catalyst herein is phosphoric acid (acid of phosphorus), preferably phosphoric acid having the popularity +5 value. The acid may comprise about 60 to about 80 weight percent or more of the final catalyst mixture prepared. Among the various phosphates, orthophosphoric acid (H ₃ PO ₄ ) and pyrophosphoric acid (H ₄ P ₂ O ₇ ) are commonly used in primary mixtures due to their low cost and easy availability, but the catalyst composites produced are In addition to being limited to the use of the class of the present invention, any other acceptable phosphate may be used. However, the different phosphates that can be used mean that each of the catalysts produced by a slightly modified process from a different acid has its own characteristic action, thus producing a catalyst having the same effect in a given organic reaction. It is not. However, catalysts prepared as described herein will have better hydrocarbon conversion properties than catalysts without pore volume distribution.

When orthophosphoric acid is used as the main component, it can be used at various concentrations of about 75% to 100% in aqueous solution. Acids containing free phosphorus pentaoxide can also be used. This means that the ortho acid may contain a constant percentage of pyroic acid corresponding to the main phase upon dehydration of orthophosphoric acid. Within this concentration range, the acid is a liquid with various viscosities and can be easily mixed with the adsorbent. In fact, the pyrophosphoric acid corresponding to the general formula H ₄ P ₂ O ₇ can be mixed with the binder at a temperature slightly above its melting point (61 ° C.) and the heating cycle provided to the pyroic acid adsorbent mixture is determined when orthoic acid is used. It has been found that can be different from.

In addition, triphosphate represented by the general formula H ₅ P ₃ O ₁₀ can also be used as a starting material for preparing the catalyst of the present invention. Such catalyst compositions may be prepared from a phosphoric acid mixture containing the aforementioned silicone materials and orthophosphoric acid, pyrophosphoric acid, triphosphate and other polyphosphoric acids.

The binder that can be used as one component of the solid phosphoric acid catalyst composite can be any material that can adsorb or bind the phosphoric acid component of the catalyst composite. One group of such materials is refractory inorganic oxides such as alumina, silica, or other metal oxides such as oxides of magnesium, calcium, phosphorus, and titanium, or mixtures thereof.

The binder is preferably a silicone material. Silicones or SiO ₂ -containing materials useful as binder components of the solid phosphoric acid catalysts of the present invention include kisselgur, diatomaceous earth, laminated earth, kaolin, table photo or artificial porous silica or mixtures thereof. However, it should be noted that the terms laminated earth, kisselgur and diatomaceous earth and porous silicon materials generally occurring in nature are used interchangeably in the context of the present invention.

One method that can be used to produce solid phosphoric acid catalyst composites with the desired pore volume characteristics of the catalyst of the present invention is to precisely control the particle size of the binder. Most binders generally contain particles of quite varying sizes. Using a binder having a very small particle size, it is expected that the prepared solid phosphate catalyst composite will contain fewer pores with a diameter of more than 10,000 mm 3, more densely than a catalyst prepared using a binder particle having a large particle size.

Small binder particles can be obtained in a variety of ways. The binder can be sorted by sieve to obtain only the smallest particles. Optionally, the binder can be mechanically sized using an Eiger Mill or a ball mill or the like that can break up large particles into smaller particles useful in the solid phosphate catalyst composites of the present invention. If binder classification is used to prepare the catalyst of the invention, the particle size of the binder is preferably in the range of 1 to 150 microns.

In preparing the catalyst composite used in the present invention, the oxygen-containing phosphoric acid and the solid binder material described above are mixed at a temperature of about 10 ° C to about 232 ° C, preferably at a temperature of about 95 ° C to about 180 ° C. To form. Satisfactory results were obtained by heating polyphosphoric acid (82% P ₂ O ₅ content) at a temperature of about 170 ° C. and then mixing this high temperature acid with room temperature diatomaceous earth. Polyphosphoric acid and diatomaceous earth form a composite having a weight ratio of phosphorus pentoxide to diatomaceous earth adsorbent of about 1.5 to about 7.5. The composite has some moisture so that its appearance is almost dry, but plastic under pressure in a hydraulic or auger extruder, which forms the composite into pieces and then cuts them into shaped particles. .

Extrusion of the phosphoric acid / binder mixture is another step in the catalyst preparation process, in which the porosity of the catalyst composite can be optimized so that the amount of pores with diameters greater than 10,000 mm 3 in the catalyst composite can be reduced. Extrusion can be used to control catalytic porosity in a number of ways by controlling extrusion back-pressure. In general, the higher the extrusion pressure, the denser the catalyst, or the smaller the porosity, pore volume, and pore diameter of the catalyst. The extrusion back pressure can be changed by various methods. One method is to change the cross sectional area of the holes in the extruder die plate. Another method is to change the moisture content of the dough being extruded, and the dried dough produces higher back pressure. Other methods are proportional to the strength or energy used to extrude the catalyst composite. The extrudate can be produced in an extrusion apparatus comprising a rotating screw or including a ram. Both types of apparatus compact the dough before being extruded through the die plate. By varying the screw speed or ramming strength with other extrusion parameters such as screw-barrel spacing, screw pitch, etc., higher extrusion energy can be consumed to densify and extrude the catalyst precursor dough.

Regarding the extrusion and other variables affecting the catalyst, it is important to (1) be aware of the desired catalytic porosity distribution, and (2) be able to understand and control the extrusion and other process parameters affecting the final catalyst. Is that. Due to the facts related to such extrusion, it is possible to clearly control the action of the above-mentioned parameters in controlling the expanded catalyst porosity so that the parameters for consistently producing the solid phosphoric acid catalyst of the present invention can be adjusted.

The solid phosphoric acid catalyst of the present invention is preferably prepared in the form of extrudates. It is contemplated that the catalyst of the present invention may be produced in a variety of shapes with the required pore diameter / pore volume distribution. In addition, extrusion is generally an efficient and inexpensive method for producing formed catalyst particles.

The catalyst composite formed by extrusion must be subjected to a crystallization step that is amorphous (or green) and converts to a catalyst composite in crystalline form for use in a hydrocarbon conversion process. In general, the crystallization step is calcination. Calcination of the amorphous extrudate can be accomplished according to any conventionally known calcination method that adjusts the temperature and time and optionally the moisture level of the calcination region. As such, crystallization of the catalyst may occur in a calcination apparatus containing a single calcination region, two calcination regions, or three or more calcination regions. The calcined region is characterized by being able to adjust at least the temperature of the region differently from other calcined regions.

The above mentioned calcination parameters are believed to have a direct effect on the final form and amount of pores and volume of pores of calcined solid phosphoric acid catalysts. As mentioned above, the final solid phosphoric acid catalyst is characterized by consisting of pores having a diameter of at least 25.0% of the total pore volume of the catalyst of at least 10,000 mm 3. In addition, the catalyst preferably has a total pore volume of 0.28 cc / g or less.

Temperature is the most important calcination condition. Temperature is important in dehydrating amorphous material and controlling the form of crystals produced as a result of calcination. High calcination temperatures, in particular calcination temperatures above 500 ° C., are well known to produce solid phosphoric acid catalysts consisting essentially of crystals of silicon pyrophosphate only. When it is desired to obtain a catalyst having silicon orthophosphate and silicon pyrophosphate crystals, it has been determined that calcination temperatures of 100 ° C to 450 ° C are most preferred and 350 ° C to 450 ° C are more preferred.

With regard to calcination temperature control, it is known that the vapor or moisture content of the calcination zone can be carefully controlled to produce the final solid phosphate catalyst composite exhibiting the desired porosity and pore volume. The steam content in the vapor of the calcining region (s) is preferably at least 5.0 mol% based on the total vapor rate for providing the catalyst with the desired porosity.

Controlling the steam content in the calciner's steam does not necessarily mean that the total or part of the steam for the calciner must be added from an external source. Large amounts of steam may be present as steam in the calcination zone because of the evaporation of water from the catalyst upon calcination. Although addition of water vapor is required to the calcination zone (s), the parameters may be adjusted by controlling variables such as total vapor rate, temperature and green catalyst moisture content passing through the calcination zone (s).

Calcining time is also an important variable. In general, the total calcination time is 20 to 120 minutes. When using more than one calcination zone, each total time is adjusted so that the total calcination time is between 20 and 120 minutes.

Another preferred aspect of the present invention is that at least one calcination zone must be operated according to the above conditions when one or more calcination zones are present. In the calciner comprising a plurality of calcining zones, the final calcining zone is more preferably operated under the predetermined conditions described above. It is not meant that other calcination zones other than the final zone cannot be carried out at the desired operating conditions, but it is believed that operating the final calcination zone at the highest temperature is the most efficient way of preparing the catalysts described herein.

In addition, the final calcining zone preferably has a degree of wetness of 5.0 mol% or more. Solid phosphoric acid catalysts calcined by this process generally have the desired porosity as described above. As a result, up to 25.0% of the total pore volume of the catalyst composite of the present invention may be composed of pores with a diameter of 10,000 kPa or more when analyzed by mercury intrusion.

Catalyst surface area and pore volume distribution are generally measured by mercury penetration and extrusion. Mercury intrusion and extrusion methods are used for catalytic porosity and are widely used in catalysis. Details can be found in the following references.

References [A. Review of Mercury Porosimetry in Advanced Experimental Techniques in Powder Metallurgy, pp. 225-252. Plenum Press, 1970; A Generalized Analysis for Mercury Porosimetry in Powder Technology, 3 (1982) pp 201-209 by R. W. Smithmick; And in D.N.Winslow, Advances in Experimental Techniques for Mercury Intrusion Porosimetry in Surface Colloid Science, vol. 13]

The catalyst of the present invention is useful in several types of hydrocarbon conversion processes in which catalyst condensation, aromatic alkylation and solid phosphoric acid catalysts are known to be useful. When used to convert olefinic hydrocarbons into oligomers or polymers, the catalysts formed as described above are generally used as granular beds in a heating reactor made of steel, through which the preheated hydrocarbon portion passes. That is, the solid catalyst of this process can be used to treat a mixture of olefin-containing hydrocarbon vapors to oligomerize or polymerize olefins, but the same catalyst also provides a liquid phase for oligomerizing or polymerizing olefinic hydrocarbons such as butylene. It may be used with reaction conditions suitable to maintain the action to produce a gasoline fraction.

If generally used to polymerize gaseous olefins, the catalyst particles are generally placed in a vertical cylindrical treatment tower or reactor or a fixed bed of the tower and the olefin containing gas is reactor or at a temperature of 140 ° C to 290 ° C and a pressure of 6 to 102 atmospheres. Pass down through the tower. These reaction conditions can be especially applied when treating olefin containing materials containing about 10-50% or more of propylene and butylene. When reacting a mixture comprising propylene and butylene, the catalyst is effective under conditions of a temperature of about 140 ° C. to about 250 ° C. and a pressure of about 34 to about 102 atmospheres.

The catalyst of the present invention is also useful for alkylating aromatic hydrocarbons as alkylating agents. Alkylating agents that can be charged to the alkylation reaction zone include, for example, various materials including monoolefins, polyolefins, polyolefins, acetylenic hydrocarbons and alkyl halides, alcohols, ethers, esters (eg, alkyl sulfates, alkyl phosphates and carboxylic acids). Various esters). Preferred olefin functional compounds are olefinic hydrocarbons including monoolefins containing one double bond per molecule. Monoolefins used as olefin functional compounds in the process of the invention are generally in gaseous or liquid form, such as ethylene, propylene, 1-butene, 2-butene, isobutylene and high molecular weight general liquid olefins (e.g., pentene, Hexene, heptene, octene, and mixtures thereof), and even higher molecular weight liquid olefins (polymers containing from 9 to 18 carbon atoms per molecule; for example, propylene trimers, propylene tetramers, propylene copolymers, etc.) Although not the same result, cycloolefins such as cyclopentene, methylcyclopentene, cyclohexene, methylcyclohexene and the like may be used. Other hydrocarbons may also be included in the alkylating agents, such as paraffins, naphthenes and compounds containing 2 to 18 carbon atoms. If the catalyst of the present invention is used as a catalyst for an aromatic alkylation reaction, it is preferable that the monoolefin contain 2 to 14 carbon atoms. In particular, the monoolefin is preferably propylene.

The aromatic substrate mixed with the alkylating agent and fed to the alkylation reaction zone is selected from the group of aromatic compounds. Benzene and monocyclic alkyl substituted benzenes of the following structure comprising 7 to 12 carbon atoms, respectively, and in the form of a mixture.

(Wherein R is methyl, ethyl or a combination thereof and n is an integer from 1 to 5).

That is, the aromatic substrate portion of the feed may be alkyl aromatic substituents containing benzene, 1-5 methyl and / or ethyl groups, and mixtures thereof. Non-limiting examples of such feed compounds are benzene, toluene, xylene, ethylbenzene, mesitylene (1,3,5-trimethylbenzene) and mixtures thereof. In particular, the aromatic substrate is preferably benzene.

In a continuous process of alkylating aromatic hydrocarbons with olefins, the reactants are continuously fed to a pressure vessel containing the solid phosphoric acid catalyst of the present invention. The feed mixture is fed to an alkylation reaction zone containing an alkylation catalyst at a constant rate or at various rates. Generally, the aromatic substrate and the olefinic alkylating agent are contacted in a molar ratio of about 1: 1 to 20: 1, preferably about 2: 1 to 8: 1. The preferred feed molar ratio contributes to maximizing the catalyst life cycle by minimizing deactivation of the catalyst by deposition of coke and crystals on the catalyst. The catalyst may be split between multiple layers in the reactor or contained in one bed in the reaction vessel. The alkylation reaction system may contain one or more reaction vessels in series. The feed to the reaction zone may flow vertically upwards or downwards through the catalyst bed in a typical plug flow reactor, or horizontally across the catalyst bed in a radial flow reactor.

In some cases, it is desirable to cool the reactants to dissipate the heat of reaction in order to maintain the desired range of reaction temperatures and reduce the formation of unnecessary polyalkyl aromatics. Alkylating agents The cooling stream consisting of olefins, alkylating agents or some reactor effluents or mixtures thereof may be injected into the alkylation reaction system to supply additional amounts of olefin alkylating agents and unreacted aromatic substrates at various locations within the reaction zone and to dissipate heat. This can be achieved in a one-stage reactor by multiple injection of the above-mentioned cooling flow components into the reaction zone via a principally located inlet line leading into the reaction zone. The amount and composition of the cooling material injected into the one-stage reaction system or the multistage reaction system can be changed as necessary. Advantages of multiple cooling injections include the removal of expensive cooling devices in the process, improved selectivity for the formation of certain alkyl aromatic compounds, provision of greater heat reduction, and the molar ratio of olefins and aromatics through the reaction zone. Optimization. As a result, the yield of certain monoalkylated aromatic compounds can be increased.

Suitable temperatures for use in the process of the present invention are those which cause a reaction between the particular olefin and the aromatic substrate used to selectively prepare the desired monoalkyl aromatic compound. In general, suitable temperatures for use are about 100 to 390 ° C., in particular 150 to 275 ° C. Suitable pressures for use in the present invention are at least about 1 atmosphere, but may not exceed about 130 atmospheres. In particular, the preferred pressure range is from about 10 to 40 atmospheres, and a liquid hourly space velocity (LHSV) of the benzene feed rate on the basis of from about 0.5 to 50hr ^-1, especially, from about 1 to 10hr ^-1. The combination of temperature and pressure used herein should select where the alkylation reaction occurs primarily in the liquid phase. In the liquid phase process of preparing alkyl aromatics, the catalyst is washed successively with the reactants to prevent the growth of coke precursors on the catalyst. This can reduce the amount of carbon formed on the catalyst and can extend the catalyst cycle life compared to gas phase alkylation processes where coke formation and catalyst deactivation are major problems.

In addition, a prescribed amount of water is preferably added to the alkylation reaction zone. A large amount of water or steam (eg steam) is added to the charge to prevent the loss of water from the catalyst and thus the reduction in catalyst activity, so that the vapor pressure of the alkylation catalyst is substantially equilibrated. The amount of this water varies in the range of about 0.01 to 6% by volume based on the volume of organic material charged to the alkylation reaction zone. The water is then generally removed along with the light by-products recovered in the first separation zone.

A substantial portion of the aromatic substrate hydrocarbons and almost all olefin alkylating agents react in the alkylation reaction zone in the presence of the solid phosphoric acid catalyst to form monoalkyl aromatic compounds and polyalkyl aromatic compounds. A preferred product of the alkylation process with the solid phosphoric acid catalyst complex of the present invention is cumene.

The following examples illustrate the use of the catalyst composites and catalysts of the present invention and are not to be considered as unduly limiting the broad scope of the invention as indicated in the claims.

Example I

This example illustrates the general production of amorphous phosphate catalyst extrudates, which are converted to crystalline solid phosphate catalysts having different amounts of macropore volume by various calcination methods such as later examples.

Chiselur clay and phosphoric acid with 82% P ₂ O ₅ content were combined in a weight ratio of 1: 2 at a temperature of 170 ° C. This material is extruded through a die into an extruder to produce an extrudate with a diameter of about 5 mm. Only materials with amorphous properties were detected by X-ray analysis of green extrudates. The extrudate thus prepared was used in the calcination experiments described in Examples II-V below. The calcination conditions include a temperature of 100 ° C. to 500 ° C., a wetness of 0 to 25 moles and a total time of 20 to 120 minutes based on the total steam in the calciner. The final catalyst was analyzed for porosity and pore volume distribution. Pore volume distribution was determined by mercury intrusion with Micromeritic Autopore 9220.

Example II

This example shows the effect of various calcination conditions on the porosity and pore volume distribution of the solid phosphoric acid catalyst. The batch of amorphous solid phosphate green extrudate from Example I was subjected to a calcination process in a small furnace in a batch of 100-150 g; It included means for passing the air and steam to which the furnace was added once at a control rate and means for precisely controlling the temperature of the furnace. After about 50 minutes under a steam content of only 3% in a furnace preheated to a furnace temperature of 392 ° C., the catalyst was removed and its porosity analyzed. The calcined catalyst had a total pore volume of 0.236 cc / g and a macropore volume of 0.071 cc / g (boots of pores having a diameter of greater than 10,000 μs) as measured by mercury intrusion. Therefore, the macropore volume accounts for 30% of the total pore volume. Such catalysts do not match the definition of the catalyst of the present invention.

A second batch of amorphous solid phosphate green extrudate from Example I was subjected to a calcination process in the same small oven as in Example II. After holding at a rate of 14% steam for about 50 minutes and holding at a rate of 22% steam addition for about 20 minutes in a furnace preheated to a temperature of 430 ° C., the catalyst was removed and its porosity was measured. By the mercury penetration method, the total pore volume of 0.23 cc / g and the macropore volume of 0.035 cc / g (volumes of pores having a diameter of 10,000 mm or more) were measured. This macropore volume accounts for 15% of the total pore volume. Such catalysts correspond to the porosity / pore volume distribution of the catalysts of the invention. It is evident from this example that the steam ratio to the calcining zone is crucial for preparing a catalyst having the porosity and pore volume distribution of the present invention.

Example III

A number of solid phosphoric acid catalysts prepared as in Example I were analyzed for total pore volume and pore volume distribution by mercury intrusion method. The results of this analysis are shown in Table 1 below.

The analyzed catalyst was then tested for catalyst life by placing it in an olefin polymerization process plant fed with propylene. The test was carried out at 68 atm, hydrocarbon feed space velocity of 1.8 to 2.1, and a temperature of 150 to 230 ° C. The test, operated at a constant conversion rate, showed that a commercial product was produced. The catalyst life values are all reported on the basis of catalyst E having a short catalyst life. The final lifetime of the catalyst was determined when the input drop through the catalyst bed was too large to continue treatment.

TABLE 1

The data indicate that there is a clear correlation between the catalyst life and the volume percentage of pores with diameters greater than 10,000 mm 3 in solid phosphoric acid catalysts. The correlation indicates that the lower the volume% occupied by the pores having a diameter of 10,000 kPa or more in the total pore volume of the catalyst, the longer the catalyst life.

Claims (8)

A porous solid phosphoric acid catalyst comprising phosphoric acid and an inorganic oxide binder, wherein 17.5% or less of the total pore volume of the catalyst is composed of pores having a diameter of 10,000 kPa or more, and the pore volume of the catalyst is about 0.28 cc / g or less. The porous solid phosphoric acid catalyst according to claim 1, wherein the inorganic oxide binder is a siliceous material selected from the group consisting of diatomaceous earth, kisselgur, artificially manufactured porous silica, and mixtures thereof. A process for converting hydrocarbons in the presence of a solid phosphoric acid catalyst by contacting the porous solid phosphate catalyst of claim 1 with the hydrocarbon feedstock under hydrocarbon conversion conditions. 4. The process of claim 3, wherein the method of converting hydrocarbons alkylates aromatic hydrocarbons with an olefin agent. The process of claim 3, wherein the hydrocarbon conversion conditions comprise a temperature of 100 ° C. to 390 ° C., 1 to 130 atmospheres, pressure and a liquid hourly space velocity of 0.5 to 50 hr ⁻¹ . 6. Process according to claim 4 or 5, characterized in that the alkylation of the aromatic hydrocarbon with the olefin activator takes place in the liquid phase. 4. A process according to claim 3, wherein the process for converting hydrocarbons is a process for producing an oligomer product by catalytic condensation of a hydrocarbon-containing feed stream. 8. The process of claim 7, wherein the hydrocarbon conversion conditions comprise a temperature of 140 to 290 ° C and a pressure of 6 to 102 atmospheres.