SE444311B - PROCEDURE FOR HYDROFORMATION OF AN ALFA OLEPHINE WITH 2-20 COLATOMES FOR THE PREPARATION OF ALDEHYDES - Google Patents

Description

k * 7800872-9 normal to iso- (or branched-chain) aldehyde isomer for the product aldehydes is high. This process utilizes certain rhodium complex catalysts and operates under defined reaction conditions to effect the olefin hydroformylation. As this new process operates at significantly lower pressures than has hitherto been required in the prior art, significant benefits were obtained including lower initial capital investment and lower operating costs; Furthermore, the more suitable straight chain aldehyde isomer could be prepared in high yields.

The hydroformylation process described in U.S. Pat. No. 3,527,809 disclosed above comprises the following essential reaction conditions: (1) A rhodium complex catalyst which is a complex combination of rhodium with carbon monoxide and a triorganophosphorus ligand.

The term "complex" means a coordination compound formed by combining one or more electron-rich molecules or atoms capable of independent existence with one or more electron-poor molecules or atoms each of which is also capable of independent existence. Triorganophosphorus ligands whose phosphorus atom has an "L" I available or undivided electron pair are capable of forming a coordinate bond with rhodium. (2) An alpha-olefin feed of alpha-olefinic compounds characterized by an ethylene carbon-to-carbon end bond, such as a vinyl group CH2 = CH- They may be straight-chain or branched and may contain groups or substituents which do not substantially interfere with the hydroformylation reaction and may also contain more than one ethylene bond.Propylene is an example of a preferred alpha-olefin (3) A triorganophosphorus ligand, such as a triarylphosphine.

Preferably, each organo moiety in the ligand does not exceed 18 carbon atoms.

The triarylphosphines are the preferred ligands an example of which is triphenylphosphine. (4) A concentration of the triorganophosphorus ligand in the reaction mixture sufficient to provide at least 2, and preferably at least 5, nml of free ligand per mole of rhodium metal, above and above the ligand complexed with or bound to the rhodium atom. (5) A temperature of from about 50 to about 145 ° C, preferably from about 12 ° C. (6) A total hydrogen and carbon monoxide pressure less than 32 kp / cm 2, preferably less than 25 kp / cm 2. <3 “78130872-9 _ (1) A maximum total pressure exerted by carbon monoxide not greater than about 75% based on the total pressure of carbon monoxide and ether, preferably less than 50% of this total gas pressure.NI It is known that during hydroformylation conditions, a portion of the product aldehydes can condense to form by-product, high-boiling aldehyde condensation products, such as aldehyde dimers or trimers. "U.S. Patent No. 4,148,830 discloses the use of these high-boiling liquid aldehyde condensation products as a reactant. is solvent removal from the catalyst, which can cause catalyst losses, unnecessary and in fact a liquid cycle containing the solvent high boiling aldehyde condensation products and catalyst is fed to the reaction zone from a product recovery zone.It may be necessary to remove a small deaeration stream to aldehyde condensation products and poisons for the reaction to excessive concentration levels.

More specifically, as disclosed in the aforementioned U.S. Pat. No. 4,148,830, a portion of the aldehyde product is included in various reactions shown below using n-butyraldehyde as an illustrative example: 7800872-9 V on I | -H2O 2cn3cx2cH2cHo - ê> cu3cn2cH2cxcncx2cH3f -> cH3cH2cH2cH = CCHO CHO - CHj - CH alaol (1) _ '”Substituted acrolein (II) 2 ~ aldøl (I) CH3CH2CH '2' 2 3 __________ J> CH CH CH CHCHCH "H CH3CH CH QHCHCHZCHB 3 2 2 I 2- 3 2 2 O 'CHZOH |. CH2occH2cH2cH3 _ ~ A_ (trimer III) (trimer IV) heat _ - ïä, CH3CH2CH2COO _ CH3CH2CH2CH2CH2Z2 CHZOH '_ \ 0 H cnzcccnzcnzcn CHCHCH CH 3 3 (dimer V) (tetramer VI) In addition, allol I may undergo the following reaction: on I cncncn CH 2 2 3 OH 2 aldol I ----> cH3cH2cH COOCH CHCHCH CH CH 2' 2 2 3 CHZCH3 (tetramer VII) 5 7800872-9 The names in parentheses in the equations shown above, aldol I, substituted acrolein II, trimer III, trimer IV, dimer V, tetramer VI and tetramer VII are for simplicity only. prepared by an aldol condensation; trimer III and tetramer VII via Tischenko reactions; trimer IV by a transesterification reaction; dimer V and tetramer VI by a dismutation reaction. products are trimer III, trimer IV and tetramer VII with minor amounts of the other products present.

Such condensation products therefore contain significant amounts of hydroxyl compounds such as, for example, trimers III and IV and tetramer VII testify. I A ': Similar condensation products are prepared by self-condensation of iso-butyraldehyde and a further series of compounds are prepared by condensation of a molecule of normal butyraldehyde with a molecule of iso-butyraldehyde. Since one molecule of normal butyraldehyde can aldolisate by reaction with one molecule of isobutyraldehyde in two different ways to produce two different aldols VIII and IX, a total of four possible aldols can be prepared by condensation reactions of a normal / iso mixture of butyraldehydes. »On eH3 cH3cn2cH2cHo + cH3eHcH3 - ê> cH3cH2cH2cH-ecxa 'cno' cno Aldol (VIII) CH3 on ïñ-CHCHCHZCH3 CH CHO 3 Aldol (IX) is isomer with trimer III and aldols VIII and IX and the corresponding aldol X produced by self-condensation of 2 molecules of isobutyraldehyde may undergo further reactions with either normal or iso-butyraldehyde to form the corresponding isomeric trimers. These trimers can further react in an analogous manner to trimer III to form a complex mixture of condensation products. U.S. Patent No. 4,244,486 discloses a liquid phase hydroformylation reaction utilizing a nm complex catalyst in which aldehyde reaction products and most of their high boiling condensation products are removed in vapor form from the catalyst containing liquid body (or solution) upon reaction. The aldehyde reaction products and condensation products are condensed out of the exhaust gas from the reaction vessel in a product recovery zone and the unreacted starting materials (eg carbon monoxide, hydrogen and / or alpha-olefin) in the vapor phase from the product recovery zone are recycled to the reaction zone. By recirculating gas from the product recovery zone coupled with additive feedstock to the reaction zone in sufficient quantities, when using C2 to C5 olefin as the alpha-olefin feedstock, it is possible to achieve a mass balance in the liquid body of the reactor and thereby remove substantially all self-boiling condensate. -condensation of the aldehyde product at a rate at least equal to their rate of formation.

According to the above-mentioned subsequent patent specification, a process for the preparation of an aldehyde containing 3 to 6 carbon atoms which comprises conducting alpha-olefin containing 2 to 5 carbon atoms together with hydrogen and carbon monoxide at a prescribed temperature and pressure through a reaction zone which contains the rhodium complex catalyst dissolved in a liquid body, continuous removal of a vapor phase from the reaction zone, conduction of the vapor phase to a product separation zone, separation of a liquid aldehyde (containing the product in the product separation zone by condensation from the gaseous unreacted starting materials), and recirculating starting materials The unreacted gaseous feedstocks plus the additive feedstocks are preferably recycled at a rate at least as high as that required to maintain a mass balance in the reaction zone.

It is known in the prior art that rhodium hydroformylation catalysts, such as hydridocarbonyltris (triphenylphosphine) - rhodium, are deactivated by certain external toxins that may be present in any of the gases fed to the reaction mixture.

See, for example, G. Falbe "Carbon Monoxide in Organic Synthesis", Springer-Verlag, New York, 1970. These toxins (X), called virulent toxins, are derived from such materials as sulfur-containing compounds (e.g. H28, COS, etc.), halogen-containing compounds 7800872-9 (e.g. HCl etc.), cyano-containing compounds (e.g. HCN etc.) and the like, and can form Rh-X bonds which do not break under mild hydroformylation conditions. If such toxins are removed from the materials fed to the reaction mixture to less than one part per million (ppm) one would therefore expect no such deactivation of the catalyst to occur, however, it has been found that this is not the case.When, for example, very pure gases ( was used in the hydroformylation of propylene and the gas recirculation procedure discussed above was used under the following conditions: temperature (OC) A - 100 CO partial pressure (kp / cm 2) 2.5 μ H 2 partial pressure (kp / cm Olefin partial pressure (kp / cm 2) 2.8 'ligand / rhodium molar ratio 94 decreased catalyst activity at a rate of 3% per day (based on the initial activity of the fresh catalyst).

It thus turns out that even the substantially complete removal of external toxins does not prevent such catalyst deactivation, which we will call internal catalyst deactivation.

The prior art, as far as we know, does not propose a solution to this problem of internal deactivation of rhodium hydroformylation catalysts and does not even realize the reasons for this.

Japanese Patent Application Sho-49-85523 discloses that in a process for hydroformylation of olefins using a rhodium-tertiary phosphine catalyst in which catalyst-containing solution separated from the reaction product is recycled to the reaction and reused, high-boiling by-products and complexes which do not have or has reduced catalytic activity formed by a change in the structure of the rhodium-tertiary phosphine complex itself and by the action of impurities, such as oxygen, halogens, sulfur, etc., which are to a small extent contained in the starting materials, in the catalyst solution. The Japanese patent application states that in order to carry out the hydroformylation reaction, the catalytic activity of the recycle catalyst solution is continuously and stably maintained at a constant level by adding fresh catalyst to the recycled solution and simultaneously removing a portion of the recycled catalyst solution.

With this procedure, the rhodium removed from the catalyst solution must be recovered based on the cost of the rhodium. However, methods for recovering rhodium from solution are complicated and the resulting hydroformylation reaction is economically disadvantageous. This patent proposes a process for reactivating the inactivated catalyst by treating the catalyst solution with carbon dioxide.

W. Strohmeier and A. Kuhn discuss in the Journal of Organoe Metallic Chemistry, 110, 265-270 (1976) the hydroformylation of 1-hexene under mild conditions (40QCJ1 atm) using HRhCO [É (C6H5) 3] 3 as a catalyst in absence of a solvent, and notes a deactivation of the catalyst. The effects of P (C6H5) 3 addition and CO partial pressure on the conversion are studied and it is stated that optimal conversion (at a normal: iso-aldehyde ratio of 99: 1) is obtained with an H2: CO ratio of 1: 1 and with the addition of P (C6H5) 3. The authors do not state the reason for the observed deactivation, nor do they suggest any solution.

Gl Wilkinson and his colleagues observed a deactivation of! the catalyst HRhCO {É (C6H5) á] 3 when used in the hydrogenation of Å alkenes IÜ. Yagupsky et al., Journal of the Chemical Society (A), 1970, p. 937 - 94l] and in fact observed that in a hydroformylation process no loss of activity of this catalyst has been observed "even after many cycles" (see pages 937? Citing CK Brown and G. Wilkinson, Tetrahedron Letters, 1969, 1725.

U.S. Patent No. 3,555,098 discloses a process for avoiding deactivation of a hydrocarbonylation catalyst by treating all or part of a liquid recycle reaction medium with an aqueous solution.

It is apparent that this treatment removes carboxylic acid by-products (formed by oxidation of the product aldehydes / alcohols) and prevents the deactivation of the reaction medium.

We have found that the just mentioned internal deactivation of rhodium catalysts under hydroformylation conditions is caused by the combination of the effect of temperature, the partial pressures of both carbon monoxide and hydrogen and the molar ratio of phosphine ligand: rhodium. It has been further determined that this deactivation produces non-catalytically active material. It would be desirable to reduce this internal deactivation problem to a minimum or eliminate it in order to achieve a truly optimal commercial process, i.e. a rhodium-catalyzed hydroformylation reaction which yields the desired product at commercially attractive conversion rates under such conditions that the catalyst remains active for an extended period of time.

The present invention encompasses a rhodium-catalyzed hydroformylation process which comprises controlling and correlating reaction conditions to reduce the internal deactivation of the rhodium complex catalyst to a minimum or substantially eliminating said deactivation. Deactivation is minimized or substantially prevented and a stable rhodium complex catalyst is provided by carefully controlling and correlating the combination of at least the carbon monoxide partial pressure, temperature and molar ratio of free triorganophosphorus ligand: catalytically active rhodium. In general, operation at low carbon monoxide partial pressure, low temperature and high molar ratio of free triorganophosphorus: catalytically active rhodium inhibits the deactivation of the rhodium complex catalyst.

By correlating these 3 parameters, which in combination are related to 1 catalyst stability, and from which the catalyst stability can be predicted, the internal deactivation of the rhodium complex catalyst can be reduced to a minimum or substantially prevented.

In its broadest aspect, the present invention encompasses a rhodium-catalyzed hydroformylation process for the preparation of aldehydes of alpha-olefins comprising the process steps of reacting the olefin with hydrogen and carbon monoxide in the presence of a rhodium complex catalyst consisting essentially of rhodium complex formed with carbon-V monoxide and a triarylphosphine, under certain defined reaction conditions as follows. (l) A temperature of from about 90 to 130 ° C; (2) A total gas pressure of hydrogen, carbon monoxide and alpha-olefin of less than about 28 kp / cm2; I (3) A carbon monoxide partial pressure of less than about 3.85 kp / cm 2; (4) A hydrogen partial pressure of less than about 14 kp / cm 2; (5) At least about 100 moles of free triarylphosphine ligand per every mole of catalytically active rhodium metal present in the rhodium complex catalyst; and selective correlation of the partial pressure of carbon monoxide, the temperature and the molar ratio of free triarylphosphine: catalytically active rhodium to limit the rhodium complex catalyst deactivation to a maximum determined percentage loss in activity per day, based on the initial activity of the fresh catalyst. It has been found that the combination of these 3 parameters exerts a synergistic effect on the stability of the catalyst. By "catalytically active rhodium" is meant the rhodium metal in the rhodium complex catalyst which has not been deactivated. The amount of rhodium in the reaction zone which is catalytically active can be determined at any given time during the reaction by comparing the rate of conversion to product: Iaoos72-9 1 ° based on such catalyst with the rate of conversion obtained using fresh catalyst. The manner in which the carbon monoxide partial pressure, temperature and molar ratio of free triarylphosphine: catalytically active rhodium is to be controlled or correlated so as to limit the deactivation of the catalyst is illustrated as follows. As an example, for the triarylphosphine ligand triphenylphosphine, the specific relationship between these 3 parameters and catalyst stability is defined by the formula: \ å 1000 l + ey F vari = stability factor = nepersk'1ogbas (para. 2.7182s1s2s) K + KT + KP + K ( L / Rh) l 2 3 4 O = reaction temperature (C) wa KQ mn = partial pressure of CO (kp / cm2) F '\ É H molar ratio free triarylphosphine: catalytically active rhodium = s.11ze = o.o7919 = o.o27s - 14, zz33 '= -o.o1155 In the above formula, and in practice, for determining KKKK ß nn'k> P of the stability factor of a catalyst under actual hydroformylation conditions in the presence of an olefin, an olefin sensitivity factor must be used to obtain of the actual stability factor. In this context, it has been found that olefins generally increase the stability of the catalyst. This will be discussed in more detail below.

The above relationship is essentially the same for other triarylphosphines except that the constants K1, K2, K3 and K4 may be different. Those skilled in the art can determine the specific constants for other triarylphosphines with a minimal amount of experimentation, such as by repeating the following Examples 1-10 with other triarylphosphines.

As understood by reference to the above formula, for given conditions relating to reaction temperature, carbon monoxide partial pressure and molar ratio of free triarylphosphine: catalytically active rhodium stability factor F can be determined. The stability factor F11 vßoosvzfeu ~ exhibits a predictive relationship with the rate at which the rhodium complex catalyst is deactivated under hydroformylation conditions. This relationship is illustrated by Figure 1 of the accompanying drawings which shows the variation in the stability factor F for different rates of catalyst activity losses for the triarylphosphine triphenylphosphine. This drawing shows that the rate of activity loss decreases in a substantially linear relationship with increasing values of the stability factor F. The determination of the maximum allowable rate of activity loss for the catalyst must finally be largely based on the economics of the process, including consideration. the cost of replacing spent or deactivated catalyst and also the value of the products, etc. For discussion purposes only, assuming that the maximum acceptable rate of loss of activity for the catalyst is 0.75% per day, Figure 1 shows that the the corresponding minimum stability factor F is approximately 770. The above equation can then be used to determine the reaction conditions that will provide this necessary minimum stability factor F and, as a result, this maximum acceptable rate of loss of catalyst activity.

Since the above equation contains 3 variables, it can be better understood with reference to Figures 2, 3 and 4 in the accompanying drawings which show the effect on the stabilization factor F of variation of 2 of these 3 variables keeping the other constant. In particular, Figures 2, 3 and 4 illustrate the effect of these 3 variables on the stability factor F for the olefin propylene, and for convenience, the following discussion will be limited to propylene as the olefin. It is to be understood, however, that a similar relationship exists for other olefins which could be illustrated in a similar manner as in Figures 2, 3 and 4.

In Figure 2, the values shown there were obtained by calculating the stability factor F when hydroformylating propylene at a constant molar ratio of free triarylphosphine: catalytically active rhodium of 170: 1 (the particular triarylphosphine being triphenylphosphine) and at varying temperatures and carbon monoxide partial pressures. . Lines A, B and C are the areas along which the stability factor F is approximately 500, 800 and 900. As shown in Figure 2, the stability factor F is highest at low carbon monoxide partial pressures and low temperatures, at a fixed molar ratio of free triarylphosphine: catalytically active rhodium.

Figure 3 illustrates the relationship between the stability factor F and varying temperatures and molar ratio of free triarylphosphine: _. Catalytically active rhodium (triarylphosphine = triphenylphosphine) with a constant carbon monoxide partial pressure of 1,75 kp / cmz for hydroformylation of propylene L Lines A, B and C are the areas along which the stability factor F is approximately 500, 800 and 900. As shown in Figure 3, the stability factor F is highest at low temperatures and high molar ratios of free triarylphosphine: catalytically active rhodium at a fixed carbon monoxide partial pressure.

Figure 4 illustrates the relationship between the stability factor F 'and varying carbon monoxide partial pressure and molar ratio of free triarylphosphine: catalytically active rhodium (triarylphosphine = triphenylphosphine, with a constant reaction temperature of 110 ° C for hydroformylation of propylene. Lines A, B and C are the ranges along which the stability factor F is approximately 500, 800 and 900, respectively. As shown in Figure 4, the stability factor F is highest at high molar ratios of free triarylphosphine: catalytically active rhodium and low carbon monoxide partial pressures at a fixed temperature. Figures 2, 3 and 4 of the drawings are intended as typical examples only. For example, if a different fixed constant temperature were used in Figure 4, the set values for the stability factor F would be different. The same applies to Figures 2 and 3 if different fixed values for molar ratio of free triarylphosphine: catalytically active rhodium and carbon monoxide partial pressure were used. each of Figures 2, 3 and 4 forms a single plane in the three-dimensional relationship between the stability factor F and the conditions temperature, carbon monoxide partial pressure and molar ratio of free triarylphosphine catalytically active rhodium, the plane being of course the same as the plane of the three-dimensional diagrams that intersect the selected value of the fixed variable in each case. These two-dimensional representations have been reported only to facilitate the description. In summary, the conditions relating to temperature, carbon monoxide partial pressure and molar ratio of free triarylphosphine: catalytically active rhodium are thus adjusted and correlated to obtain minimal catalyst deactivation in the following manner.

The threshold determination refers to a maximum acceptable rate of loss of catalyst activity. With this value and with the addition of, for example, the relationship illustrated in Figure 1, the minimum stability factor F can be determined. The above equation is then solved to determine the values of the three variables set to obtain this minimum stability factor F, and in this context such representations as Figures 2, 3 and 4 are helpful in determining specific conditions. which will provide a stable catalyst.

For the purposes of the present invention, it is assumed that a realistic value for the rate of loss of activity of the rhodium complex catalyst in a commercial process is 0.5% per day, based on the activity of the fresh catalyst. The term “activity” refers, for example, to the amount of product that is produced expressed as gram moles / liter hour. Of course, any other standard procedure can be used to determine the relative activity at any given time. However, according to the present invention, AVI generally applies that the maximum loss of activity of the rhodium complex catalyst V should be 0.75% per day and highly advantageous results are obtained when the maximum rate of loss of catalyst activity is 0.3% per day, whereby both values are based on the activity of the fresh catalyst. It is to be understood, however, that in its broadest sense, the present invention should not be limited to any maximum rate of loss of catalyst activity as this would be due to many different factors, as noted above. Rather, the present invention provides a mechanism A for obtaining any maximum rate of loss of catalyst activity by regulating and correlating the hydroformylation reaction conditions. In other words, once a maximum acceptable rate of loss of catalyst activity has been determined, the present invention provides a person skilled in the art with the tools for regulating and correlating the reaction conditions necessary to obtain catalyst stability. The values set forth above for the maximum rate of loss of catalyst activity should therefore not limit the scope of the present invention as they are provided to prescribe to those skilled in the art how the present invention is to be practiced. As noted above, the presence of the olefin in the hydroformylation reaction increases the stability of the catalyst; i.e. it inhibits the deactivation caused by the combination of carbon monoxide, hydrogen, temperature and ligand / rhodium molar ratio. One can determine the effect of the olefin on the calculation of the stability factor. It has been found, for example, that upon hydroformylation of propylene, reaction conditions which will provide long-term catalyst stability (i.e., a low rate of loss of catalyst activity) give a stability factor F, determined from Figure 1 at the observed rate of loss of catalyst activity. Using about these conditions and the above formula, however, a stability factor F of about 870 is calculated. It is only necessary to then make the appropriate modification in the above equation to include the effect of the propylene on the stability factor. Similar data can be readily obtained for other olefins and the necessary modifications can be made to the above formula to determine the actual reaction conditions to be used to obtain the benefits of the present invention, i.e. long-term catalyst stability.

The process of the present invention is expected to be suitable for hydroformylation of alpha-olefins containing up to 20 carbon atoms. The process of the present invention is particularly suitable for the hydroformylation of alpha-olefins having 2 to 5 carbon atoms, including ethylene, propylene, 1-butene, 1-pentene and the like, and this is therefore a preferred embodiment. The process of the present invention is particularly suitable for hydroformylating propylene to produce butyraldehydes having a high normal to iso ratio; i.e. the butyraldehyde predominating in the product is the normal butyraldehyde and consequently this is currently the most preferred embodiment. The alpha-olefins used in the process of the invention may be straight chain or branched and may contain groups or substituents which do not substantially interfere with the process of the hydroformylation reaction.

The rhodium complex catalyst used in the process of the invention consists essentially of rhodium complexed with carbon monoxide and a triarylphosphine ligand. The term Ü consists essentially of "does not mean to exclude, but instead to include hydrogen complexed with rhodium, in addition to carbon monoxide and a triarylphosphine.

However, this language is intended to exclude other materials in amounts that poison or deactivate the catalyst; Typical examples of triarylphosphine ligands are triphenylphosphine, trinaphthylphosphine, tritolylphosphine, tri (p-biphenyl) phosphine, tri (p-methoxyphenyl) phosphine, p-N, N-dimethylaminophenylbis-phenylphosphine and the like. The most suitable catalyst does not have a rhodium-bonded halogen, such as chlorine and the like, and contains hydrogen, carbon monoxide and triarylphosphine complexed with rhodium metal to produce a catalyst which is normally soluble in liquids which can be used as a solvent in the reaction and which is stable under the reaction conditions determined and controlled according to the invention. Tri-phenylphosphine constitutes the preferred ligand and, as previously pointed out, an excess of triarylphosphine ligand is present in the reaction medium. Higher molar ratio of free triarylphosphine: catalytically active. rhodium metal promotes the stability of the catalyst. "Free" triarylphosphine refers to the triarylphosphine which is not bound to or complexed with the rhodium atom of the active complex catalyst.

The theory of how such ligands complex with rhodium is disclosed in the aforementioned U.S. Pat. No. 3,527,809. According to the present invention, the amount of free triarylphosphine in the reaction medium is sufficient to provide a molar ratio of free triarylphosphine: catalytically active rhodium of at least 100.

Advantageous and preferred results are obtained when this molar ratio is at least 10 °. The upper limit of this molar ratio does not prove to be particularly critical and is largely dictated by commercial and economic considerations. Of course, the amount of free triarylphosphine depends on the necessary stability factor F, which in turn is related to the molar ratio of free triarylphosphine: catalytically active rhodium by the above equation. The rhodium complex catalyst can be prepared by methods known in the art. For example, a preformed stable crystalline solid of rhodium hydridocarbonyl-tris (triphenylphosphine), RhH (CO) [? (C6H5) š] 3, can be introduced into the reaction medium. This material can be prepared, for example, by a method described in Brown et al., Journal of the Chemical Society, 1970, pages 2753-2764. Alternatively, a rhodium catalyst precursor such as: A Rh 2 O 3, Rh 4 (CO) 12, or Rh 6 (CO 16 and the like are introduced into the reaction medium. In a preferred embodiment, rhodium carbonyltriphenylphosphine acetylacetonate or rhodium dicarbonylacetylacetonate is used.

In any case, the active rhodium complex catalyst is prepared in the reaction medium under the hydroformylation conditions.

The amount of catalyst present in the reaction medium should be at least the amount necessary to catalyze the hydroformylation of the alpha-olefin to produce the product aldehydes. In general, the rhodium concentration in the reaction medium can vary from about 25 ppm to about 1200 ppm, preferably about 50 ppm to about 400 ppm, catalytically active rhodium calculated as free metal. The triarylphosphine ligand is present in sufficient quantities to prepare the catalyst complex and to provide the above minimum number of moles of free triarylphosphine per mole of catalytically active rhodium metal. Typically, the triarylphosphine ligand is present in the reaction medium in an amount of from about 0.5 to 30% by weight by weight of the total reaction medium and in an amount sufficient to provide the desired number of free triarylphosphine ligand per mole of catalytically active rhodium. . The amount of olefin fed to the reaction mixture depends on several factors, such as the size of the reactor, the reaction temperature, the total pressure, the amount of catalyst, etc .. In general, the higher the olefin concentration in the reaction medium, the lower the catalyst concentration that can be used. to achieve the right conversion ratio to aldehyde products in a given reactor size to be. Since partial pressure and concentration are related, the use of higher olefin partial pressures leads to an increased proportion of the olefin in the product leaving the reaction mixture. Furthermore, since some saturated hydrocarbon can be produced by hydrogenating the olefin, it may be necessary to purify a portion of the product gas stream to remove this saturated product before any recirculation to the reaction zone and this would be a source of loss for the unreacted olefin contained in the product gas stream. . Consequently, it is necessary to balance the economic value of the olefin loss in such a treatment room against the economic savings associated with lower catalyst concentration.

The reaction temperature may, as indicated above, range from about 900 DEG to about 130 DEG C., the lower temperatures promoting catalyst stability. The particular temperature used in the reaction will, of course, depend on the necessary stability factor F, since temperature is related to the carbon monoxide partial pressure and the molar ratio of free triarylphosphine: catalytically active rhodium according to the above equation. In general, by controlling the temperature as prescribed above to obtain the necessary stability, within the foregoing temperature range, the advantages of the present invention can be obtained. It is preferred for the process according to the invention to operate at a temperature of 1 from 90 to 120 ° C. A significant advantage of the process described in U.S. Pat. No. 3,527,809 is the low total pressure of hydrogen and carbon monoxide required to carry out the hydroformylation reaction. The process of the present invention operates at total pressures of carbon monoxide, hydrogen and olefin of less than 28 kp / cm 2, preferably less than 24.5 kp / cm 2. The minimum total pressure is not particularly critical and is mainly limited only by the amount of reaction gases necessary to obtain the desired reaction rate.

The additive gases fed to the reaction medium will usually comprise the olefin, carbon monoxide and hydrogen. As previously pointed out, external toxins, such as sulfur and sulfur-containing compounds, as well as halogens and halogen-containing compounds, and the like, are to be excluded from the additive gases because it is known that such materials poison the catalyst and can deactivate the catalyst rather rapidly. Accordingly, it is desirable to reduce the amount of such toxins in all gases fed to the reaction. Of course, the amount of such toxins that can be tolerated is determined by the maximum acceptable rate of loss of activity for the catalyst discussed above. If it is possible to allow a small amount of such toxins and still obtain a catalyst with the desired stability, then such small amounts can be tolerated. It is generally desirable to reduce the amount of such toxins in the auxiliary gases to less than 1 part per million. This can be achieved by methods known in the art.

The partial pressure of hydrogen in the reaction mixture forms an important part of the present invention. Although it is not reflected as such in the formula given above, the effect of the hydrogen partial pressure is included in the constant K1 in the formula. Accordingly, according to the process of the present invention, the partial pressure of hydrogen should be less than about 14 kp / cm 2 and preferably it should range from about 4.2 to 11, 2 kp / cm 2. the value to be determined depending on the necessary stability factor and the relationship between the hydrogen partial pressure and the carbon monoxide partial pressure as discussed below.

The partial pressure of carbon monoxide has a significant effect on the stability of the catalyst and should generally be less than about 3.85 kp / cm 2. Of course, the particular partial pressure used will depend on the necessary stability factor. As a general rule, lower carbon monoxide partial pressures provide more stable catalysts. In accordance with the process of the present invention, it is preferred that the partial pressure of carbon monoxide be from about 0.14 to 1.4 kp / cm 2. The minimum partial pressure of carbon monoxide is not critical in that it is limited predominantly only by the desired reaction rate and the possibility of olefin hydrogenation occurring.

It is stated in U.S. Pat. No. 3,527,809 that the aldehyde isomer ratio of normal to iso for the aldehyde products decreases as the partial pressure of carbon monoxide increases relative to the hydrogen partial pressure. In the process of the present invention, in a similar manner, the partial pressure of carbon monoxide relative to the partial pressure of hydrogen has an effect on the isomer ratio of the product aldehydes. In general, to obtain the more desirable normal aldehyde isomer, the ratio of the partial pressures of hydrogen carbon monoxide should be at least about 2: 1, preferably at least about 8 =: 1. As long as the partial pressures of each of carbon monoxide and hydrogen are controlled within the limits As described above, there is no critical maximum ratio for hydrogen: carbon monoxide - partial pressures The reaction time, or residence time of the olefin in the reaction zone, is usually the time sufficient to hydroformylate the alpha-ethylenic bond of the alpha-olefin. As a general rule, the uptake into the reaction zone can vary from about several minutes to about several hours in duration, and as will be appreciated, this variable will be influenced to some extent by the reaction temperature, the choice of alpha-olefin and catalyst, the free ligand concentration. the total pressure, the partial pressure exerted by carbon monoxide and hydrogen, the rate of conversion and other factors. As a general rule, it is desirable to achieve the highest possible conversion rate for the least amount of catalyst used. Of course, the final determination of a conversion rate is influenced by many factors including the economics of the process. A significant advantage of the present invention is that catalyst deactivation is reduced to a minimum or substantially prevented while obtaining excellent conversion rates over extended time periods. It is preferred to carry out the process according to the invention in a liquid phase in the reaction zone containing the rhodium complex catalyst and, as a solvent therefor, the high-boiling liquid aldehyde condensation products.

By the term "high boiling liquid aldehyde condensation products" as used herein is meant the complex mixture of high boiling liquid products obtained as a result of the condensation reactions of some of the aldehyde products of the process of the invention, as illustrated above. Such condensation products can be prepared in advance or produced in situ in the present process. The rhodium complex catalyst is soluble in these relatively high boiling liquid aldehyde condensation products while exhibiting excellent stability over extended periods of continuous hydroformylation. In a preferred form of the process according to the invention, the high-boiling liquid aldehyde condensation products are prepared which are to be used as solvents before introduction into the reaction zone and the initiation of the process. It is also preferred to keep the condensation products illustrated by acrolein II above, and its isomers, at low concentrations in the reaction medium such as below about a weight percent. and lower on the total weight of the reaction medium. These high-boiling liquid aldehyde condensation products are described in more detail, and methods for their preparation are described in more detail in U.S. Patent Application No. 556,270 filed March 7, 1975, and for a more detailed description reference is made to said U.S. patent application. V '_. .

It is also preferred in accordance with the method of the present invention to utilize the gas recirculation procedure described in U.S. Patent Application 674,823 filed April 8, 1976; This gas recirculation process is broadly described above. If the aforementioned high-boiling liquid aldehyde condensation products are used as solvents, the liquid body in the reaction zone will comprise a homogeneous mixture containing the soluble catalyst, the free triarylphosphine ligand, the solvent, the product aldehydes and reactants, alpha-olefin and carbon monoxide.

The relative proportion of each reaction product in solution is controlled by the amount of gas passing through the solution. An increase in this amount reduces the equilibrium aldehyde concentration and increases has-. by-product removal from solution. ' The by-products include the high-boiling liquid aldehyde condensation products. The reduced aldehyde concentration leads to a reduction in the rate of formation of the by-products. The double effect of increased removal rate and reduced rate of formation means that the mass balance of by-products in the reactor is very sensitive to the amount of gas passing through the liquid body.

The gas cycle typically involves the addition of hydrogen, carbon monoxide and alpha-olefin. The most significant factor, however, is the amount of recycle gas returned to the liquid body as this determines the degree of reaction, the amount of product formed and the amount of by-product (as a result) which is removed.

Operation of the hydroformylation reaction with a given flow rate of olefin and synthesis gas (ie carbon monoxide and hydrogen) and with a total low amount of gas recycle less than a critical threshold result in a high equilibrium aldehyde concentration in solution and consequently in high by-products. formation rates.

The rate of removal of by-products in the vapor phase effluent from the reaction zone (liquid body) under such conditions will be low because the low vapor phase effluent flow rate from the reaction zone can only result in a relatively low rate of transfer of by-products. The net effect is a build-up of by-products in the liquid body solution, which causes an increase in the volume of the solution with a concomitant loss of catalyst productivity. A purge is therefore taken from the solution when the hydroformylation process is carried out under such low gas flow rate conditions to remove by-products and consequently maintain a mass balance over the reaction zone. . ' However, if the gas flow rate through the reaction zone fi is increased by increasing the gas recycle rate, the solution aldehyde content decreases, the by-product formation rate decreases and the by-product removal rate of the vapor phase effluent from the reaction zone increases. The net effect of this change is an increase in the proportion of the by-products removed with vapor phase effluent from the reaction zone. Increasing the gas flow rate through the reaction zone even more by a further increase in the gas recirculation rate leads to a situation where by-products are removed in the vapor phase effluent from the reaction zone. the same speed at which they are formed; thereby creating a mass balance over the reaction zone. This is the critical threshold gas recirculation rate which constitutes the preferred minimum gas recirculation rate used in the process of the invention. If the process is operated at a gas recirculation rate higher than this threshold gas recirculation rate, volume of the liquid zone in the reaction zone will decrease and the gas recirculation zone will decrease. the threshold rate, a portion of the crude aldehyde by-product mixture is returned to the reaction zone from the product separation zone to keep the volume of the liquid phase in the reaction zone constant.

The critical threshold gas recycle flow rate can be obtained by a process by passing for a given olefin and synthesis gas (the mixture of carbon monoxide and hydrogen) feed rate. Working at recirculation speeds below the critical threshold speeds will increase the volume of the liquid phase over time.

Working at the threshold speed keeps the volume constant. Working above the threshold speed reduces the volume. The critical threshold gas recirculation rate can be calculated from the vapor pressures at the reaction temperature of the aldehyde or aldehydes and for each of the by-products present. By a method operating at a gas recirculation rate at or greater than the threshold rate, by-products are removed in the gaseous vapors which are removed from the reaction zone containing the liquid body at the same rate as or faster than they are formed and thus do not accumulate in the liquid phase in reaction conditions. pure liquid body »containing the catalyst from the reaction zone for the removal of by-products. A by-product of the hydroformylation process is the alkane formed by hydrogenation of the alpha-olefin. Thus, in the case of hydroformylation of propylene, a by-product is propane. A purge stream can be taken from the gas recycle stream from the product recovery zone to remove propane and prevent its buildup within the reaction system. This purge stream will contain, in addition to unwanted propane, unreacted propylene, all inert gases introduced into the feedstock and a mixture of carbon monoxide and hydrogen. The purification stream can, if desired, be subjected to conventional gas separation processes, for example cryogenic processes, for the extraction of propylene or it can be used as a fuel. The composition of the recycle gas is mainly hydrogen and propylene. However, if the carbon monoxide is not consumed at all in the reaction, the excess carbon monoxide will also form part of the recycle gas. Usually the recycle gas will contain alkane even with pre-recycle purification.

The preferred gas recirculation is further illustrated with reference to Figure 5 of the accompanying drawings which shows a schematic flow diagram suitable for practicing the preferred recirculation process of the invention.

In the drawing, a stainless steel reactor 1 is provided with one or more disc impellers 6 containing perpendicularly mounted blades and rotated by means of a shaft 7, with a suitable motor_ (not shown). Below the impeller 6, a circular tubular spreading device 5 is placed for feeding the alpha-olefin and synthesis gas plus the recycle gas. The spreading device 5 contains a plurality of holes of sufficient size to provide sufficient gas flow into the liquid body at approximately the impeller 6 to provide the desired amount of reactants in the liquid body.

The reactor is also provided with a steam jacket (not shown) by means of which the contents of the vessel can be brought up to reaction temperature at start-up and internal cooling coils (not shown). Vaporous product effluent from the reactor 1 is removed via line 10 to the separation device 11 where they are passed through a vapor pad 11a therein to return some aldehyde and "condensation product" and to prevent potential transfer of the catalyst. The reactor effluent 13 is passed through line 1. cooler 14 and then through line 15 to the capture vessel 161 in which the aldehyde product and each by-product can be condensed out of the exhaust gases (effluent). Condensed aldehyde and by-products are removed from the capture vessel 16 through line 17. Gaseous materials are passed at line 18 to separation device 19 which contains a and the recirculation line ZOQ Recirculation gases are removed through line 21 to line 8 from which a purge stream through line 22 is drawn to regulate content saturated hydrocarbon and maintain the desired system pressure. The remaining and larger part of the gases can be recirculated via line 8 to line 4j into which the additive reactant feeds are fed through lines 2 and 3. The combined total amount of reactants is fed to the reactor 1. The compressor 26 facilitates the transport of the recycle gases.

Q Fresh catalyst solution can be added to the reactor 1 through line 9. The only reactor 1 can of course be replaced by a plurality of reactors.

The crude aldehyde product from line 17 can be treated by conventional distillation to separate the various aldehydes and condensation products. A portion of the raw material can be recycled to the reactor 1 through line 23 and fed as indicated by the dashed line 25 to a point above the impeller 6 to maintain the liquid level in the reactor 1 if required.

As noted above, the most preferred embodiment of the present invention is hydroformylation of the alpha-olefin propylene.

The stability of the nx fl complex catalyst is improved by the processes of the invention and in the case of propylene the reaction is controlled by the process of the invention within the following conditions: temperature: about 90 to about 120 ° C total gas pressure of hydrogen, carbon monoxide and propylene: less than about 24 .5 kp / cm 2 carbon monoxide partial pressure: about 0.14 to about 1.40 kp / cm 2 vase partial pressure: approximately 4.2 to about 11.2 kp / cm 2 triarylphosphine: triphenylphosphine molar ratio free triphenylphosphine: catalytically active rhodium: about 150 In the hydroformylation of propylene according to the invention, it has been found and therefore preferred that the conditions of the reaction can be controlled and correlated within these ranges so that the calculated stability factor F is at least about 850 as this will provide the minimum rate of loss of catalyst activity. The invention is further illustrated by the following examples.

Examples 1 to 33. These examples illustrate the effect of the reactant gases, hydrogen and carbon monoxide, temperature and molar ratio of free triarylphosphine rhodium metal on the deactivation of a rhodium hydroformylation catalyst. The procedure used in Examples 1 to 19 was as follows: To about 20 g of an isobutyraldehyde trimer solvent, Films 351 (trade name for Union Carbide) in a stainless steel high pressure reactor was added a sufficient amount of a rhodium catalyst precursor and free triphenylphosphine for the provision of the molar ratio-free triphene phosphine: rhodium metal shown in Table I.

The reactor was connected to a gas manifold and heated to the temperature shown in Table I. Carbon monoxide and hydrogen were then added to the partial pressures shown in Table II and the temperature was maintained for the time indicated in Table I after which the solution was allowed to cool. The resulting solution was then exposed to an equimolar mixture of propylene, hydrogen and carbon monoxide at IQOOC and the rate (rl) of butyraldehyde formation in gram moles / liter-hour was determined.

The rate (rz) of butyraldehyde formation was also determined for an identical catalyst solution that had not been exposed to the deactivation conditions.

Examples 20-33 were performed in a similar manner except that a larger volume of solution was exposed to the deactivation conditions and samples were taken periodically during this time and tested for activity in true ways. I The results are reported in the following table I: 7000072-9% 2 "TABLE I Deactivation conditions Iakt- - co- 11 ~ partiaL- part§a1", ta9? N_ (2) A Time. Temp. Pressure 2 pressure (1) activity Exemgel __ (¿1 _) _ (° c) (Kp / cm) (kzycm) TPP / an (0) 1 40 130 2,00 11,2 zs i 2 2 4f 130 2,00 11,2 «30 _14 3 24 110 2.00 11.2 »0 11 4 20 100 2.00 11.2 70 53 5- 24.1 100 1.40 1.172 70 - 61 s 10 90 0.70 o 5.00» 25, - 07 7 10 120 0.70 5.00 20, 33's 30f 90 0.70 “11.20 '100 79 9 30 V 120 2.45 4.90 100 19 10 30 90 3.05 5.00 25" 42 11 20 100 ---- --N2 ---- - 70 90 12 4 130 ---- “m2 ---- - 70 _ 90- 13 4 130 o 2.00 _ 70 47 14 4 130 o 2.00 70 s1 15 24 130 0 I '. 11,2 _ 70 24 10 24 100 3,05 0 70 I se 17 20 100 3,05 Üo 70 V 73 _ 10 22 100 2,00 '0 0 (3) 70 greater than 19 20 100 3,50 0 ( 4) 70 störršçä0__n 20 4 115 2.90 2.90, 79 1291 21 24 11s 2.90 '2.90. 79 1s 22 4 _1115 2.90 M 2.98 131. as 23 24 115 2.90 '2.90 131, _ 22 24 4 11s 2.90 2.90 _ 157 71 (1) TPP / Rh = molar ratio free triphenylphosphine: rhodium metal (2) Observed activity = (rl / rz) x 100 (3) and (4) = propylene present in an amount sufficient to give a partial pressure of 3.85 resp. 1.05 kp / cmz ..___._.__._... ~ _-. ~ .. ~ ._._._-_.._ ,, _._. “..._ 78Û0872 ~ 9 25 V TABLE I (continued Deactivation conditions _ »°°" Hz "íâkån <2) partial-partial- 9. .t Time TENP pressure« pressure. aktlvl et Ešâsasš 199.. <° C> k çmz; kQ¿cm2¿ TPP / Rhfl) <5) 25 24 115 2; 9s _ 2,98 - 151 42 25 I; 4 115 3,50 1.25 119. _59 _ 27 fa 115 3.50 1.25 “79 z _ 47¿ za; (4 115 1; 75 "3,50 119 '~ 1o' 29 I 'is 115 1,75 3,50 ïvs" so J 30 f4 115 3,50 V 0 fyg I - vi 35 31 7 6 _ 115 _ 3 , 5o o * vs A so 325! J 2 115 o 3,50 _ / -19 I ao 33 ~ 6 115 o _ 3,50 ffvs, 15 (1) TPP / Rh = molar ratio free triphenylphosphine: rhodium metal (2) Observed activity = (r1 / r2) x 100 f While none of Examples 1 to 33 illustrate a hydroformylation process of the present invention, since one or more of the reactant gases (olefin, hydrogen or carbon monoxide) are not present, the values in Table I show that lower partial pressure of carbon monoxide (cf. examples 26 and 28), lower temperatures (cf. examples 6 and 7) and higher molar ratio of free triarylphosphine: rhodium metal (cf. examples 20 and 22) promote catalyst stability (the more stable catalysts being shown in the table of the higher Examples 18 and 19 illustrate the effect of the presence of olefin on the stability of the catalyst.

Example 34 - 48.

The following Table II shows the rate of loss of activity of a rhodium hydroformylation catalyst under hydroformylation conditions. The stability factor shown in the table was calculated using the formula given above and the conditions given in the respective examples. The loss of activity was determined by measuring the production rate of aldehyde in gram moles / liter-hour at a given time and comparing the measured value against the rate of aldehyde production for the fresh catalyst. The reaction conditions are given in Table II. 26 mm _ Qvw _ _ = ° ~ _ m «. ~. _. .m ~ .m> ~. ° ° - .mwwv. @ ~. _ = vw °° ~ m «. ~ U = _ m ~ .w ~>. ° ° -. ~. ~ <H. fl ßw _ == ~ _ _ _ ° w. ~ _ _ = _ .w ~. æ_ mm. ° mø fi wv °. ~ _. = ~ w__ _ _ß @ «__ /_mß.w_ _ __: =, .m ~ _ ~ _ mmæo _ = - mv ... H _ 23 SN _ Så _ ._ .Qš _25 m3 I m. ° awm aan . ._ m «. ~ _. m>.> mm.a q flfl mv N ... _35 .SN _ .min. _ .. EK 36 m3 _ 2.

WN _ Sh _ Z 38 _. _. _ _ 3. » _ 36 .En _ 2 °. ~ Açß _ QQH ..m «. ~. = __ mm.m «ß.o == ~ _ _ av N. å; 2: _ So _ _. mïm E ... 8 _ 3 TN QS m3 _ 2.6 ._ 8G mmå m3 _ å .Ä 2G. 2: Sä _. _ 83 SO _ E; S °. ~ E fi m -Q. _ = æ. ~. m ~ .m _ ~ m. ~ Qø fl _ un @ .H ° ww_ çm m «. ~ nwmoum m ~ .m _« mH Qo fl _ mn ~ ._ omm ° = -__ _ w «~ ° cmuu _ _> n. «_ H« .w _ ° H ~ _ __ vn * H96 hu ... å. _ _ uo fi w * Sñæšå. _ .wæo \ mw._ _ _ _ 5GB .. .weušë âsuäwvc ._ 8A. H fl memxß u mn fl umw l fl umu flfl xuhuu umu An. xoæuu xuauu un »muwm fi uu. _ _: nu mu fl åuxm Lqnmum .äøwuumm _ u .Hm fl wuøm .àn fl qumm _ _ _ ._ __: fl øwo = ou i fl w fifl 7800872-9. _ _ mou enn wåm: oo w ~ = .än å fi näxnë mmmmw fi šm .Q m8 så m fi ö m? .än w Swnush fl ^ 8 + ~ E mmwwwunä 8.

H fifl unmu fl som meamm n nm \ mma .H. Examples 35 to 46 are within the scope of the present invention and illustrate the relationship between the reaction conditions, the stability factor F and the stability of the catalyst. Example 34 illustrates the fact that the olefin ethylene has a more catalyst stabilizing effect than the open. In Example 34, the carbon monoxide partial pressure is higher than in the present invention, but a stable catalyst is obtained due to the very high phosphine / rhodium ratio used Å and also due to the fact that ethylene increases the stability of the catalysts more than other olefins. Examples 47 and 48 are not considered to be within the invention with regard to the presence in the synthesis gas of the sulfur impurities. 2 Exemgel 49 - 52.

These exhibit deactivation of rhodium hydroformylation catalysts expressed in terms of the change in the rate of hydroformylation with time. The value of Integrated Turnover Number (IION) given in Table III is defined as the number of moles of aldehyde formed per mole of rhodium metal in the catalyst and constitutes an abstract measure of catalyst life.g The reaction conditions and results are reported in the following Table III. Examples 49, 50 and 52 illustrate the process of the present invention by illustrating the effect of various olefins on catalyst stability.

Example 51 utilizes an internal olefin which is not intended to be within the scope of the present invention. 28 * 7800872-9 Gmno fl uxmmu> ø Gmwnwn _ 3% änm fi m fl à mus mamma? äno fl nšmw ».å» w fl åm mä »» wnm fi mmn n »u fi åuua ß 2: _ Hwêu flfl .HQVOGHDQ wwumumwnø fi .h 209m -Nv H Swan» H som meemw n ÉÉÉ. .S ä m3 x HA 2 SïN: wuønå RJ SIH 03. N ... m ~ 3 x NK w _ _ En ", cm fi ønå ärm _ ÃJ 02 G TE. M3 x .in 2 _ fl å _ a fi m Nwå Så _ mm _ om ßn mo fl x må mn mHÄ _ cmmoum _ _ wwå. moÄ om _ 3 twßßš fl å šzo fi. .dåmwm .Nm fi mmq _ 3%? äwwwwmews Hwmswxm iä fi mï - mwm. .Amwmwma | Hmww fi ßmm _ H HH .HAWÉNH

Claims (2)

1. ”7800872-9 PATENTKRÅ! A process for hydroformylating an alpha-olefin having 2-20 carbon atoms to produce aldehydes having one carbon atom more than the alpha-olefin by reacting the alpha-olefin with hydrogen and carbon monoxide in the presence of a rhodium complex catalyst consisting essentially of rhodium complexed with carbon monoxide and a triphenylphosphine, and in the presence of free triphenylphosphine characterized in that it comprises carrying out the process at a temperature of from 900 DEG to 130 DEG C., a partial pressure of carbon monoxide of less than 3, Q5 kp / omz, a partial hydrogen pressure of less than 14 kp / cm 2, a total gas pressure of hydrogen, carbon monoxide and alpha-olefin of less than 28 kp / cm 2, and at least 100 moles of free triphenylphosphine per mole of catalytically active rhodium metal; and reducing to a minimum or substantially preventing deactivating the rhodium complex catalyst to a maximum determined rate of loss of activity by regulating and correlating the carbon monoxide partial pressure, temperature and molar ratio of free triphenylphosphine: catalytically active rhodium metal within said values to provide the minimum stability factor F necessary to provide substantially the minimum rate of loss of activity according to Figure 1 of the accompanying drawings, wherein the stability factor F is defined by the equation: F = _3229? 1 + e vari F = stability factor, V e = nepersk log base (2,7l828l828), y = Kl * + KZT + 1 <3P + .V1 <4 (L / Rh), Kl = -8) ll26, K2 = 0.079 19, T = reaction temperature (OC), K3 = 0.0278 - 14.2233, P = carbon monoxide partial pressure (kp / Cmz), K4 = - 0.01155, and A (L / Rh) = molar ratio free triphenylphosphine: catalytic -active 7800872-9 30 xoalummeuall. 2. A process according to claim 1, characterized in that the alpha-olefin has 2-5 carbon atoms. 3. A process according to claim 1, wherein the alpha-olefin is propylene. 4. A process according to claim 1, characterized in that the alpha-olefin is ethylene. 5. A process according to claim 1, wherein the alpha-olefin is l-butene. Process according to one of the preceding claims, characterized in that the partial pressure of carbon monoxide is from 0.14 to 1.4 kp / cm 2. _ 7. ' Process according to any one of the preceding claims, characterized in that the temperature is from 900 to 120 ° C. Process according to any one of the preceding claims, characterized in that the molar ratio of free triphenylphosphine: catalytically active rhodium metal is at least 150. Process according to any one of the preceding claims, characterized in that the total gas pressure of hydrogen, carbon monoxide and alpha-olefin is less than 24.5 kp / cm 2. Process according to one of the preceding claims, characterized in that the partial pressure of hydrogen is from 4.2 to 11, 2 kp / cm 2. ll. Process according to any one of the preceding claims, characterized in that the ratio of the partial pressure of hydrogen carbon monoxide is at least 2: 1. _, ._ _... .._._ l _._._......._.._ .. 7800872-9 31 12. A method according to any one of the preceding claims, characterized in that the ratio of the partial pressure of hydrogen: carbon monoxide is at least 8: 1. 13. A process according to any one of the preceding claims, characterized in that the catalyst is dissolved in a solvent comprising the high-boiling liquid condensation products of the aldehydes. Process according to any one of the preceding claims, characterized in that the maximum determined rate of loss of activity of the catalyst is 0.75% per day; A method according to any one of the preceding claims, characterized in that the minimum stability factor F is approximately 850. 16; Process according to any one of the preceding claims, characterized in that the partial pressure of carbon monoxide is from 0.14 to 1.4 kp / cm 2, the partial pressure of hydrogen is from 4.2 to 11.2 kp / cm 2, the total gas pressure of hydrogen, carbon monoxide 2 and the ratio of free triphenylphosphine: catalytically active rhodium metal varies from 150 to 300 moles of free triphenylphosphine per mole of catalytically active rhodium metal. and the alpha-olefin is less than 24.5 kp / cm 17. The process according to claim 16, characterized in that the alpha-olefin is propylene and the stability factor F is about 850.