KR20010023998A - Manufacture of Methyl Isobutyl and Diisobutyl Ketone - Google Patents

Abstract

The present invention reacts a reactant consisting of DMK and / or IPA in the presence of an aldol condensation catalyst with an effective amount of an additional reactant selected from the group consisting of mesityl oxide (MSO), methyl isobutyl carbinol (MIBC) and mixtures thereof. Catalytically treating the MIBK and DIBK from the DMK and / or IPA (optionally in the presence of water) while further improving the ratio of DIBK: MIBK in the product stream. It relates to a method of manufacturing. The reaction temperature can be varied to affect the product ratio obtained. Preferred catalysts are copper-based catalysts. Excess hydrogen in total is required and this can be achieved by injecting or recycling hydrogen and / or while balancing the exothermic and endothermic reactions. The product ratio of DIBK: MIBK is altered by the present invention to produce less than normal amounts of DIBK with increasing DMK and / or IPA conversion, resulting in improved control of the product ratio of these substances. have.

Description

Manufacture method of methyl isobutyl ketone and diisobutyl ketone

MIBK and DIBK are known acetone derivatives and co-produced by catalytic reaction of DMK and / or IPA. Typically, aldol condensation catalysts are used, and in preferred embodiments a copper (Cu) -based catalyst is used.

MIBK and DIBK are generated in the output at the original ratios they have in each of these processes. However, this ratio was not constant, i.e., the ratio of DIBK: MIBK increases as MIBK generation increases. This phenomenon is well illustrated by Fig. 1, which is measured experimentally, which is a line graph showing the ratio of DIBK / MIBK according to the action of the generated MIBK. Unfortunately, market demands do not necessarily conform to the original chemical properties. Therefore, as can be easily predicted in the figure, when increasing the productivity of the MIBK to meet market demands, a large amount of DIBK may be generated thereby resulting in the need for some storage or disposal of the DIBK, and There is a need for overcoming adverse conditions in energy and inefficiency of the raw materials involved. Thus, it is desirable to have a method in which the ratio of DIBK / MIBK is easily controlled, which makes it possible to control the amount of material actually desired and to manipulate it to obtain more desirable amounts of other materials. Separate common relationships between levels. The present invention provides such a method.

The present invention relates to a process for preparing methyl isobutyl ketone (MIBK) and diisobutyl ketone (DIBK) by catalytic reaction of acetone (DMK) and / or isopropyl alcohol (IPA). In particular, the present invention relates to a method for adjusting the ratio of MIBK: DIBK produced.

Figure 1 shows the approximate ratio of DIBK: MIBK according to the generation rate of a given MIBK.

Summary of the Invention

The present invention provides a reactant consisting of DMK and / or IPA (optionally in the presence of water) in the presence of an aldol condensation catalyst, mesityl oxide (MSO) and methyl isobutyl carbinol (MIBC), and mixtures thereof By reacting an additional effective amount of additional reactants, which catalytically prepares MIBK and DIBK from DMK and / or IPA (optionally in the presence of water) and at the same time the ratio of DIBK: MIBK This provides a further improved control method. By "effective amount" is meant an amount that results in varying the ratio of DIBK / MIBK as shown in FIG. Preferably such ratio change will result in at least about 5%, more preferably about 10%. The reaction temperature may be increased or decreased, as a result, if desired, the conversion of DMK and / or IPA and the corresponding ratio of DIBK / MIBK will be increased or decreased respectively.

The present invention further provides that the process is selected from the group consisting of reactants consisting of DMK and / or IPA, mesityl oxide (MSO), methyl isobutyl carbinol (MIBC), and mixtures thereof in the presence of an aldol condensation catalyst. DMK and / or optionally in the presence of water, characterized by reacting an effective amount of additional reactant and further reducing or increasing the reaction temperature by reducing or raising the reaction temperature. Methods for catalytically preparing MIBK and DIBK from IPA while improving the ratio of DIBK / MIBK.

Detailed description of the invention

Regardless of the specific chemistry theory, the co-generation of MIBK and DIBK from IPA and / or DMK includes the following scheme:

Isomers of MSO and DIBK are present, and the isomers will probably be present in the chemical mixture, but are not in significant amounts for the present invention and are considered normal MSO and DIBK, respectively.

The MSOs, MIBCs or mixtures thereof according to the invention are derived from the external raw material in the process or, optionally, from the appropriate recycled air stream in the process, and with the usual DMK and / or IPA, and optional water reactor Co-feed with MSOs and / or MIBCs co-fed in the present invention may be provided in-process from external sources, and the MSOs and / or MIBCs produced in the overall reaction chemistry noted above may be required reactants for the practice of the present invention. It can be used to determine the preferred amount of.

The addition of complementary MSO and / or MIBC will be described in more detail below, which, when properly controlled with the proper temperature control expected, makes the ratio of DIBK / MIBK predictable and suitable. In other words, the current ratio of DIBK / MIBK can be influenced by the smaller amount of DIBK produced per MIBK per unit than shown in FIG. 1. This allows the operator to select the desired production level at which one or the other product does not have the other product levels originally indicated.

Those containing MSO, MIBC or mixtures thereof and other reactants in the system are co-fed to a reactor containing DMK and IPA and optional water at a concentration of at least about 20% per weight of the total inlet stream. Can be. As will be appreciated by those skilled in the art, a reasonable degree of experimentation may be required so that satisfactory operating results can be obtained within any given manufacturing system. The optimum conditions for the appropriate concentration will be known to those skilled in the art and will of course vary with local operation conditions such as the ability of the reaction system to remove heat and externally supply hydrogen. Preferably at least one MSO or MIBC will be present in the inlet stream at a concentration of at least about 2% by weight, more preferably about 5% by weight.

As pointed out, the level of DIBK was also significantly increased in advance as the MIBK level was preferably increased. Since MSOs and MIBCs are readily converted to MIBKs in catalytic reactions, it is expected that additional supply of MSOs and / or MIBCs will produce a significant amount of DIBK. Another surprising result of the method of the invention is that no increase in DIBK occurs, ie the ratio of DIBK / MIBK shown in FIG. 1 is preferably changed. The reaction temperature can be manipulated to further change the ratio and is an important option in the application of the present invention.

It will also be readily pointed out that MSO is a by-product of the process of the present invention, and it is also a surprising aspect of the present invention that external MSOs can be supplied to the invention without leaving any excess thereof in the product. MSOs are generally at concentrations of up to 0.5% by weight in the product mixture, and in particular are found as impurities in the MIBK because their boiling point is close to the boiling point of the MIBK. Thus, the surprising advantage of the present invention is that it prevents the production of MSOs at a considerably high rate, and preferably allows MSOs to be produced at a lower rate than the prior art processes. In fact, it has been found that about 20% of additional MSO relative to the total feed mixture weight can be co-fed without increasing the MSO of the product stream. Roughly approximating, about one pound of MSO and / or MIBC in a typical converter where IPA is the raw material can be supplied for each pound of DMK made in the converter, It will be appreciated that at least about 90% of MSO and / or MIBC will be spent producing MIBK and DIBK. The changing temperature will also change the ratio of DIBK / MIBK, more details are described below.

Obviously from the reaction chemistry pointed out above, hydrogen is the reactant and product in the system. It is desirable that large amounts of hydrogen be maintained throughout the process. Such conditions are typically cited in the term hydrogen balance. As will be appreciated by those skilled in the art, preferred hydrogen levels may be achieved by the above process means which either supply pure hydrogen or recycle spent or generated hydrogen.

In addition, the system has certain capabilities for removing heat. This condition is commonly referred to as heat balance. If a large amount of MSO is fed into the system, the exothermic reaction between MSO and hydrogen will release a large amount of heat, deactivation of the catalyst may occur, and hydrogen will be consumed in significant amounts. As such, manufacturing units are generally limited to the amount of MSO that can be supplied without causing confusion in the hydrogen balance and / or heat balance to the extent that the results will not be acceptable.

If the overall system is maintained at an acceptable heat balance, the control of the reaction can be further improved. As such, it is desirable to take into account the stoichiometry of the reactions mentioned above in addition to the heat involved in the reaction. For systems that contain only IPA as the initial raw material, the most ideal type of insulation system can be supplied for the total amount of DMK produced by one pound of MSO. This is because the heat used for the production of DMK has an endothermic amount as much as the hydrogenation from MSO to MIBK generates heat. This also maintains excess hydrogen because pounds per hour of DMK production produces about 0.02 pounds / hour of hydrogen, while MSO pounds / hours consumes about 0.01 pounds / hour. . Most systems are not ideal and may therefore be able to successfully supply more MSOs than can be suggested by the aforementioned methods.

According to the present invention, the concern about supplying a large amount of MSO can be lessened by the input of MSO, which is limited to the concentration level mentioned here, and can also be solved by using a mixture of MSO and MIBC. Since the reaction of MSO and hydrogen releases about 460 Btu / lb MIBK, and the conversion from MIBC to MIBK requires about 250 Btu / lb, dilution of MSO with MIBC increases the endotherm of the reaction resulting in the MSO reaction. It is observed that the fever can be alleviated. Selection of the optimum ratio will be made by routine calculations and experience by one of ordinary skill in the art.

Bi-functional copper-based aldol condensation catalysts capable of carrying out hydrogenation / dehydrogenation chemistries are preferably used by the present invention, while the advantageous effects of the present invention as mentioned above Is not believed to be dependent on all particular catalyst compositions. Thus, it is contemplated that the present invention is applicable to all catalysts used in the production of MIBK and / or DIBK from IPA and / or DMK. Such catalysts include Pd, ZnO, Cu chromite, and Al / Mg / Zn / Ni mixture base catalysts. The catalysts are often combined with one or more metals such as Cu, Cr, Ni, Pd or Zn for hydrogenation / dehydrogenation chemistries, one or more base metals for condensation chemistries (eg, Na, Ca, Mg, Li and the like). However, the preferred catalyst used in the examples below consists of about 10% Cu, about 1% Ca, and about 0.5% Cr relative to the weight of the metal (eg preferably alumina) remaining on the support. For the purposes of the present invention, the composition of the catalyst is not strictly limited in a narrow range. For example, the concentration of the hydrogenation catalyst (eg, Cu, Cr, Ni, etc.) may be about 5-15% by weight, while the concentration of the base metal (eg, Ca, Na, Mg, etc.) About 0.5 to 3 weight percent. With regard to the above-mentioned preferred catalyst composition, Cr is optional and the range may be about 0 to 1%.

In addition to those described below with respect to temperature changes to improve the ratio control of DIBK / MIBK, the choice of reaction temperature within the temperature operating envelope of the selected catalyst is not limited to a very narrow range, Generally it is about 150 to 300 ° C, preferably about 180 to 270 ° C, more preferably about 200 to 260 ° C. Temperatures above about 270 ° C. depend on the thermal stability of the particular catalyst in use, and such temperatures are preferably avoided to minimize catalyst deactivation. Obviously low temperatures are preferred for the reaction. Also as the temperature is increased, the equilibrium begins to drive the hydrogenation reaction towards the MSO, increasing the concentration of MSO.

The choice of reaction pressure is not too strictly limited. An operation of about 10-30 psig is proposed.

Similarly, the flow rate through the reactor is also not limited to a narrow range and may generally be an LHSV of about 0.1 to at least 10.0, preferably about 0.1 to at least about 3.0 LHSV. The term "LHSV" means liquid hourly space velocity and is generally used to measure the volume feed rate in the liquid phase per volume of catalyst (as used in the examples below, LHSV Although the measurement is made at atmospheric pressure and in liquid phase, the reaction must be made in gas phase and under pressure). Preferably the flow rate will be about 0.5-1.5 LHSV, more preferably about 0.75-1.25 LHSV.

As mentioned, raising or lowering the temperature can be applied to the reaction with the co-feed of MSO and / or MIBC as a means to further control the ratio of DIBK / MIBK. The present invention also shows that by manipulating the temperature in conjunction with the MSO / MIBC co-feed, it is possible to improve the properties that allow a wider range of DIBK / MIBK ratios. According to the theoretical example, if the system contains typical operating conditions and feed compositions, the system can produce 13% MIBK and 4% DIBK. 10% by weight of the feed is exchanged with MSO. The system can generate 20% MIBK and 6.5% DIBK. In fact, if the MIBK reaches 20%, the system will generate 8.5% DIBK; Therefore, a relative decrease of about 25% was obtained for DIBK. If the temperature in the theoretical example (i.e. with 10% MSO in the feed rate and the temperature of typical operating conditions) is lowered by 15 ° C, the system will produce 17% MIBK and 4% DIBK. Therefore, a relative decrease of about 33% was obtained for DIBK. Surprisingly, as a result of co-feeding MSO and varying temperature, MIBK was increased by 30% without increasing DIBK as compared to the embodiment with general reactor conditions and feed composition. Furthermore, the co-feed and temperature of MSO / MIBC can reduce the production of DIBK and at the same time increase the MIBK.

Without being bound by any particular chemical theory, a reasonable explanation of the results follows. Hydrogenation / dehydrogenation reactions occur easily over the entire temperature range of operation. The condensation reaction is very temperature dependent. Therefore, MIBK is easily generated if MSO / MIBC is supplied. However, if the temperature is lowered sufficiently, the condensation reaction of DMK and MIBK to form DIBK is significantly reduced.

The following examples are intended to illustrate the invention and are not intended to limit the invention in any way.

Example 1

About 170 cc / hr (LHSV = 0.85) of a mixture of 45 wt% DMK, 45 wt% IPA and 10 wt% H ₂ O was fed to 200 cc of Cu-based catalyst at 220 ° C. and 20 psig. The reactor product contained about 13.5 wt% MIBK and 4.4 wt% DIBK (DIBK / MIBK = 0.33). All other reactor conditions were left under essentially the same conditions and the feed mixture was changed to DMK 39%, IPA 39%, H ₂ O 9% and MSO 13%. The reaction product contained about 22.5% MIBK and 8.1% by weight DIBK (DIBK / MIBK = 0.36). From the results shown in FIG. 1, the DIBK obtained by running the system with higher IPA / DMK conversion was 10.1%. Therefore, a relative decrease of 20% in the production of DIBK was obtained by co-supplied MSO. The amount of MSO released from the reactor did not increase essentially.

Example 2

About 150 cc / hr of a mixture of 45% DMK, 45% IPA and 10% H ₂ O was fed to 200 cc of Cu-based catalyst at 220 ° C. and 20 psig. The reactor product contained about 14.1 wt% MIBK and 4.4 wt% DIBK (DIBK / MIBK = 0.29). All other reactor conditions were essentially the same and the feed mixture was changed to DMK 40%, IPA 40%, H ₂ O 10% and MIBC 10%. The reaction product contained about 18.7% MIBK and 5.4% by weight DIBK (DIBK / MIBK = 0.28). From the results shown in FIG. 1, the DIBK obtained by running the system with a higher IPA / DMK conversion was 7.3%. Therefore, a relative decrease of 25% in the generation of DIBK was obtained by the MIBC co-supplied.

Example 3

The same procedure as in Example 2 was carried out except that the temperature was lowered to 210 ° C. The reaction product contained 14.3% MIBK and 2.2% DIBK. Therefore, by the co-feed and temperature drop of MIBC, the production of MIBK was maintained, and DIBK production was reduced by about 50% compared to Example 2.

Example 4

The procedure of Example 1 was followed except that the mixture contained 36% by weight DMK, 36% by weight IPA, 10% by weight H ₂ O and 18% by weight MSO. The similar inactivation proceeded by operating the catalyst for several weeks as being similar in effect to lowering the temperature. The reaction product contained 25% MIBK and 5% DIBK (DIBK / MIBK = 0.2). From the results shown in FIG. 1, the DIBK obtained by running the system at higher IPA / DMK conversion was 12.6%. Therefore, a relative reduction of about 60% in DIBK production was obtained by co-feeding MSO and effectively lowering the reaction temperature. In fact, as compared to Example 1, the production of MIBK was increased by about 85% without substantially increasing the DIBK.

Example 5

About 190 cc / hr (LHSV = 0.95) of a mixture of 45% DMK, 45% IPA and 10% H ₂ O was fed to 200 cc of Cu-based catalyst at 250 ° C. and 20 psig. The reactor product contained about 10.5 wt% MIBK and 2.2 wt% DIBK (DIBK / MIBK = 0.21). All other reactor conditions were essentially the same and the feed mixture was changed to DMK 40%, IPA 41%, H ₂ O 9% and MSO 10%. The reaction product contained about 15.8% MIBK and 3.2% by weight DIBK (DIBK / MIBK = 0.20). From the results shown in FIG. 1, the DIBK obtained by running the system with a higher IPA / DMK conversion was 5.4%. Therefore, a relative reduction of about 40% in the production of DIBK was obtained by co-supplied MSO.

Example 6

A mixture of about 90 cc / hr (LHSV = 0.45) with 15 wt% DMK, 14 wt% IPA, 3 wt% H ₂ O and 66 wt% MIBC was fed to a 200 cc Cu-based catalyst at 275 ° C. and 20 psig. . The reactor product contained about 49 wt% MIBK and 16.5 wt% DIBK (DIBK / MIBK = 0.34). Therefore, without reaching the uncontrollable ratio of DIBK / MIBK, the production of MIBK and DIBK with the mixture was significantly increased.

Claims (17)

A reactant consisting of DMK and / or IPA, and optional water in the presence of an aldol condensation catalyst, and an effective amount of additional reactant selected from the group consisting of mesityl oxide (MSO), methyl isobutyl carbinol (MIBC) and mixtures thereof And catalytically preparing said MIBK and DIBK from said DMK and / or IPA, and optionally water, further controlling said ratio of DIBK: MIBK. The method of claim 1, wherein the additional reactant results in a change in the DIBK: MIBK ratio of at least about 5% from that shown in the figure. The method of claim 2, wherein the additional reactant results in a change in the ratio of DIBK: MIBK at least about 10% from that shown in the figure. The process of claim 1, wherein the additional reactant is present in the injection airflow of the reactor at a concentration of at least about 2% by weight. The method of claim 1, wherein the additional reactant is present in the injection airflow of the reactor at a concentration of at least about 5 wt%. The method of claim 1 wherein the additional reactant comprises a mixture of MSO and MIBC. The method of claim 1, wherein at least a portion of the MSO and MIBC are present in the reaction mixture as a result of the reaction of the DMK and / or IPA. Reacting a reactant consisting of DMK and / or IPA in the presence of an aldol condensation catalyst with an effective amount of additional reactant selected from the group consisting of mesityl oxide (MSO), methyl isobutyl carbinol (MIBC) and mixtures thereof And further reducing or increasing the aldol condensation reaction by lowering or raising the reaction temperature, while further improving the ratio of DIBK: MIBK, optionally in the presence of water. Catalytically preparing said MIBK and DIBK from DMK and / or IPA. The method of claim 8, wherein the ratio of DIBK: MIBK is less than can be obtained in the absence of the additional reactant. The method of claim 8, wherein said additional reactant comprises a mixture of MSO and MIBC. The method of claim 8, wherein at least a portion of the MSO or MIBC is present in the reaction mixture as a result of the reaction of DMK and / or IPA. The method of claim 1 further comprising changing the ratio of DIBK / MIBK by changing the reaction temperature. The method of claim 8 further comprising changing the ratio of DIBK / MIBK by changing the reaction temperature. The method of claim 1, wherein the LHSV is about 0.5-1.5. The method of claim 8, wherein the LHSV is about 0.5-1.5. The method of claim 1 wherein hydrogen is supplied in excess. 9. A method according to claim 8, wherein hydrogen is supplied in excess.