DE3029700A1 - CATALYTIC PROCESS FOR THE PRODUCTION OF SATURATED ALIPHATIC MONOCARBONIC ACIDS WITH 6 TO 9 C ATOMS - Google Patents

Description

The invention relates to an improved process for the preparation of organic saturated aliphatic Monocarboxylic acids, which contain six to nine carbon atoms, by oxidation of the corresponding aldehydes to the Acids using a combination of copper and manganese catalysts contained in the acids formed are soluble. The acids produced by the process according to the invention are generally used for production of esters for use in colors, artificial flavors, fragrances and the like used. Recently, the production of esters of heptanoic acid and nonanoic acid, which are used as starting mixtures' used for synthetic lubricating oils has attracted particular interest.

The acids prepared according to the invention, which contain an even number of carbon atoms, often come in of nature in substantial amounts, while the acids, which contain an odd number of carbon atoms, in general does not occur in large quantities in nature. The creation of production facilities for the extraction of monocarboxylic acids with six to new carbon atoms from naturally occurring materials is in general not practical and extremely expensive. It is convenient to use petrochemical equipment with which good yields in the production of acids from readily available starting hydrocarbons be achieved.

For the production of saturated aliphatic monocarboxylic acids according to the invention are suitable as an

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ORIGINAL INSPECTED-

common materials olefins with five to eight carbon atoms, which by hydroformylation into aldehydes with six to nine carbon atoms are converted. The latter are in turn oxidized catalytically to their respective acids. The hydroformylation and oxidation processes for making acids are well known. What at The aim of this process are improved catalysts that have a high carbon efficiency (carbon efficiency) to the desired product with high conversion ', whereby good overall yields are achieved.

Various catalysts are known for the oxidation of aldehydes to acids. These include, for example Nitric acid oxidation catalysts and soluble metal catalysts, e.g. manganese (II) acetate, cobalt acetate and cupric acetate. For example, the usage is of manganese (II) acetate known for the large-scale production of acetic acid from acetaldehyde. The JA-PS 52-33614 describes the use of a combination of manganese (II) acetate and copper (II) acetate catalysts for the oxidation of acetaldehyde to acetic acid. As a reason for using a combination of manganese and copper catalysts is stated in this patent that the amount of exceptionally low levels of impurities formed, in particular formic acid, should be reduced. Manganese (II) acetate alone as a catalyst for the production of acetic acid from acetaldehyde was found to be just as effective in terms of the carbon number selectivity for the desired product and with regard to the yields like the combination of manganese (II) acetate and copper (II) acetate. It also avoids certain Disadvantages of such combinations, e.g. increased corrosion and rapid failure of the pump seals by copper deposits.

In comparative tests, manganese (II) acetate is used alone

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ORIGINAL INSPECTED

no significantly worse efficiency to formic acid in the oxidation of acetaldehyde to acetic acid than achieved with the combination of manganese (II) acetate and copper (II) acetate. Furthermore, when using of manganese (II) acetate as a catalyst gives results quite similar to the combination of manganese (II) acetate and copper (II) acetate as a catalyst in the oxidation of propionaldehyde to propionic acid and valeraldehyde obtained to valeric acid.

However, the production of acetic acid from acetaldehyde is different from the production of acids, which contain at least six carbon atoms, from their corresponding aldehydes insofar as that in the case of oxidation atom oxidized by acetaldehyde is the oxygen-containing carbon atom to which a methyl radical is bonded. The presence of the methyl radical results in more stable intermediate products of the reaction compared to aldehydes, the four or more methylene radicals between the oxygen-containing carbon atom and the methyl radical 'ent-. keep. The products that are formed during the oxidation of acetaldehyde include acetic acid, Methyl acetate, formaldehyde, methyl formate, formic acid, carbon dioxide, carbon oxide, methane and water. on the other hand the products that can be formed in the oxidation of, for example, heptanal comprise most of them Products that are formed during the oxidation of acetaldehyde plus heptanoic acid, namely, among others, hexane, hexene, Hexanal, hexanol, hexanoic acid, valeric acid, butyric acid, propionic acid and various esters, dehydrated

3o aldol dimers and lactones.

Copper (II) acetate alone is an oxidation catalyst for the production of acetic acid from acetaldehyde, however, the carbon efficiencies are compared to acetic acid with this catalyst much less than with

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ORlGiNAL INSPECTED

Manganese (II) acetate.

In contrast to the finding in the oxidation of acetaldehyde and propionaldehyde, it was found that the Use of manganese acetate alone in the oxidation of higher aldehydes. e.g. heptanal, low sales of Aldehyde (7o-75%) required to have satisfactory carbon efficiencies to achieve acids. This requires the recovery of unreacted aldehyde by distillation for recycling if this process is to be economically expedient. Further significant aldehyde losses arise through condensation to form high-boiling compounds in the aldehyde circulation column.

The invention relates to an improved catalytic process for the production of organic aliphatic Monocarboxylic acids with six to nine carbon atoms by oxidation of the corresponding aldehyde of the acid. In this process, a combination of manganese and copper compounds is used as a catalyst are soluble in the acids formed. The manganese and copper compounds can be used in such amounts be that the molar ratio of manganese to copper is in the range of about 5: 1 to 0.5: 1. To the organic aliphatic monocarboxylic acids having six to nine carbon atoms, which are obtained by the process according to the invention include hexanoic acid from hexanal, heptanoic acid from heptanal, and octanoic acid from octanal Nonanoic acid from nonanal.

The process according to the invention leads to industrially interesting high carbon efficiencies of aldehydes to acids with high aldehyde conversions (8o - 9o%). With high carbon efficiencies and high aldehyde conversions can be a single-stage liquid phase reactor

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can be used satisfactorily. The method according to the invention also enables the use of a two-stage liquid-phase reactor system with straight Passage in which the mixture containing the unreacted aldehyde from the catalytic reaction of the first stage contains, can be fed to a catalytic reaction of the second stage with total conversions of aldehyde up to 97% or more at total carbon efficiencies to acids up to 90% or more. With the two-stage Liquid phase reactor system with straight passage an operation with recirculation of unreacted aldehydes is generally not necessary.

In the one-stage liquid-phase reactor system and in each stage of a two-stage liquid-phase reactor system the reactions can take place under a pressure in the range of

about 1.4 to 10.3 bar, preferably about 5.9 to 6.2 bar ■ carried out with air in the temperature range from about 50.degree. to 80.degree will.

Air is commonly used as the source of molecular oxygen, but pure oxygen gas can also be used will. The molecular oxygen can be supplied in at least the stoichiometrically sufficient amount to convert the material to be oxidized into carboxylic acid and to compensate for by-products such as carbon dioxide or to take into account. The ratio of the total oxygen supplied to the total organic used Material is a number that can vary widely depending on the particular composition of the input material , the desired products and other process design factors depends. In general, the oxygen-containing gas is passed through the liquid reaction mixture Pearl in sufficient quantity to prevent oxygen starvation prevent the risk of damage caused by a low oxygen concentration or a high ratio of carbon oxide to carbon

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dioxide or both is displayed in the residual gas.

The oxidation reaction can be carried out in the liquid phase, i.e. the aldehyde to be oxidized is in liquid form. In general, the carboxylic acid formed as the reaction product serves as a solvent in which the reaction takes place. A problem with separation of water in the oxidation reactors occurs when Nonanal is oxidized, but is not present in the oxidation of heptanal. The water is extracted and if the catalytic converter fails, the efficiency is reduced by about 2%. Water separation does not take place instead, when acetic acid is supplied with the nonanal in such an amount that about 2 wt .-% acetic acid in the Reactor fluid are maintained.

The reaction time or the residence time in the reactor can be about 0.1 to 5 hours and is preferably about 0.3 to 1 hour. The dwell time is calculated as follows:

. ,. _ Solution volume in the reactor, ml residence time - _aldehyde _ _{Use rate f m} i / h.

A combination of any copper and manganese compounds present in the acids that make them up is suitable as a catalyst form, are soluble. Preferred copper and manganese compounds are soluble manganese (II) and copper (II) salts, with manganese (II) acetate and copper (II) acetate especially to be favoured. During the oxidation, these compounds can be present in catalytic amounts of about 1o to 2,000 ppm manganese and copper, preferably 2oo to 600 ppm based on the weight of the liquid reaction medium. The molar ratio of manganese to Copper can range from about 5: 1 to 0.5: 1 and is preferably in the range from about 3: 1 to 1: 1.

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ORIGINAL INSPECTED

The carboxylic acid can be obtained from the oxygen-containing reaction product mixture can be isolated by various known methods. Generally this is done through Distillation.

The main difficulty of the method according to the invention is the presence of copper compounds in the product. Acid cleaning can precipitate copper and. mechanical problems such as erosion of Boiling and pump wheels as well as rapid failure of pump seals lead to. The copper and manganese metals can be precipitated from the organic acid formed as a product by adding oxalic acid as its oxalate will. The oxalates obtained in this way can then be removed from the organic acid before their purification and isolation be filtered off. Furthermore, copper and manganese can be formed from the organic saturated aliphatic Acids with six to nine carbon atoms can be separated off by adding aqueous oxalic acid in turn as their oxalates are precipitated. The manganese and copper oxalates are deposited in the aqueous phase, which can easily be separated from the organic acid formed as product. The organic acid can be from the aqueous phase can be decanted and further purified by distillation. This procedure is described in DE-PS

(Patent application P of the same

Days according to the applicant's US patent application o65 24o) described.

The invention is further illustrated by the following examples.

3o examples 1 to 4

Liquid phase oxidations of acetaldehyde to acetic acid using cupric acetate as the only one Oxidation catalyst were made in a tubular reactor

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ORIGINAL INSPECTED

Glass with an inner diameter of 3.81 cm and a length of 122 cm
external circulation through a heat exchanger
3.45 bar and 8o C. An oxygen-nitrogen mixture (molar ratio 9o: 1o) was used instead of air
used to facilitate residual gas measurements and the

Reduce loss of acetaldehyde through relaxation. These experiments were carried out under such conditions that the conversions (acetaldehyde concentration at
steady state) by the rate of oxygen supply
to the reactor were regulated. After the end of each reaction ^: the products were distilled in batches, with. the desired products have been obtained. The applied; The reaction conditions and the conversions and efficiencies achieved are listed in Table I below. '

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Table I.

oxidation of acetaldehyde to 1 acetic acid with 3 copper (ID- acetate as catalyst example 2 4th

150 , 72 150 _r 52 150 , 53 158 , 42 2 ,8th 3; 3 ,8th 2 ,8th 849 , 0 826, .6 768 , 6 832 , 2 14th 14, 14th 14th 530 _r 5O 500 48 500 _r 52 490 r47 O, r5 O, 1 O ₁ , 9 0, r2 88; , 2 86 5 87 , 2 85 , 4 98 9 96, 3 96, .1 98 ,1 95 1 98 8th 99 2 97 1 85 0 85 3 87 9 . 85 5 6, 8th 4, 9 3, 0 4, 4th 0, 1 0, 8th 1, 2 1, 4th 6, 6, 6, 7,

Catalyst concentration, ppm (Cu ⁺⁺ )

Test duration, hours, rate of use, g / hour.

Oxygen input, moles / hour

Volume of the solution in the reactor, ml

Dwell time, hours Oxygen conversion,%

Acetaldehyde balance,% ("accountability") acetaldehyde conversion,% efficiency (%) to acetic acid
Methyl acetate

Formic acid

Carbon dioxide

In addition to the products mentioned, small amounts of formaldehyde, methyl formate, carbon oxide, methane and 25 ethylidene diacetate formed.

Some of the results in Table I above were calculated using the following equations:

_v ., .. _ volume of the solution in the reactor, ml dwell rate of acetaldehyde, ml / hour.

Moles of O ₂ used - moles of O ₂

Oxygen turnover = in the _{residual gas 1nn}

Mol O ₂ used ^{x ιυυ}

Moles of acetaldehyde and equivalents

in the product _10Q

30 Acetaldehyde balance = moles of acetaldehyde used

τ. i. υ i »j TT j- α converted acetaldehyde, mol acetaldehyde conversion,% =

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Efficiency to _ moles of product formed _1n _

Product,% ~ moles of acetaldehyde used - ^X

Moles of unreacted acetaldehyde

Examples 5 to 8

These experiments were carried out under the same conditions as in the case of Examples 1 to 4, but with a combination of manganese (II) acetate and copper (II) acetate was used. The results obtained are given in Table II.

Table 'II

Oxidation of acetaldehyde to acetic acid using manganese (II) acetate / copper (II) acetate mixtures

as catalysts

Example 5 6 7 8

Catalyst concentration, 15

Cu, ppm 120 62 120 73 110 123 , 20 Mn, ppm 150 2 150 7th 130 116 , 0 Duration of the experiment, hours 2, 3 2, 0 3.53 2 , 7 Deployment Rate, g / hr 842, 844, 844.2 900 Use of oxygen,
Moles / hour 14, 47 13, 49 11.5 11 , 49 Volume of the solution in
Reactor, ml 500 520 2 550 550 ,1 Dwell time, hours O, 5 0, 4th 0.52 0 , 2 Oxygen conversion,% 8th 90 4th 89.1 91 , 3 Acetaldehyde Balance,%
("accountability") 98 4th 97 6th 98.4 .96 , 0 Aldehyde Conversion,%
^ Efficiency (%) to 98 5 98 5 97.0 92 ,8th acetic acid 88 3 90 2 94.2 96 , 2 Methyl acetate 1, 5 1, 6th 1.6 0 ,1 Formic acid O, 0, 0.2 0 Carbon dioxide 8th, 6, 3.8 1

^{x In} addition to the products mentioned, small amounts of formaldehyde, methyl formate, carbon oxide, methane and ethylidene diacetate were formed.

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Examples 9-14

The tests were carried out under the same conditions as in the case of Examples 1 to 8 with the difference that that manganese (II) acetate (114 parts Mn per million parts average) is used alone as the catalyst became. The results are given in Table III.

Table III

Oxidation of acetaldehyde to acetic acid using manganese (II) acetate as a catalyst (114 ppm Mn ⁺⁺ on average)

Example 9 10 11 12 13 14

Circulation rate, 1 / hour Test duration, hours Deployment Rate, g / hr

Use of oxygen, Moles / hour

Volume of the solution in the reactor, ml residence time, hours oxygen conversion,%

Acetaldehyde balance,% (accountability)

Acetaldehyde Conversion,% ^ efficiency (%) to

Acetic acid methyl acetate formic acid carbon dioxide

250 250> 300> 300> 300> τ300

3.45 3.53 3.0 3.50 3.50 4.0

755 853 841 774 765 786

10.1 9.2 9.9 14.9 12.3 10.6 '

460 475 490 440 460 480

0.48 0.44 0.46 0.45 0.48 0.49

86.2 91.6 84.6 76.6 85.0 91.4

98.1 98.0 101.4 99.0 98.8 98.5

97.1 93, ο 91.4 99.3 98.3 97.8

92.8 95.4 94.7 85.6 87.9 91.9

1.0 0.8 0.9 1.0 1.1 1.2

0.3 0.2 0.3 0.7 0.5 0.4

4.7 2.7 3.3 11.0 8.6 5.1

In addition to the products mentioned, small amounts of formaldehyde, methyl formate, carbon oxide and methane were formed.

Examples 15-20

The tests were carried out under the same conditions as in the case of Examples 1 to 8 with the same calculations carried out, but manganese (II) acetate (600 ppm Mn

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- 1 ί -

on average) was used alone as a catalyst. The results obtained are given in Table IV. "

Table IV

Oxidation of acetaldehyde to acetic acid using manganese (II) acetate as a catalyst (600 ppm Mn ⁺⁺ on average)

Example 15 16 17 18 19

Circulation rate, 1 / hour 300 300 82 , 4 50 300 300 300 300 Test duration, hours 3.2-5 3, 737 460 ,1 3.98 4.02 3.58 3.93 Deployment Rate, g / hr 853 11 0, ,8th 745 727 814 751 Use of oxygen,
Moles / hour 10.4 76 , 6 10.1 9.1 8.9 11.4 Volume of solution
in the reactor, ml 480 97 , 5 465 500 430 420 Dwell time, hours 0.44 98 , 0 0.52 0.55 0.42 0.44 Oxygen conversion,% 84.1 91 , 4 84.2 84.4 90.8 78.9 Aldehyde balance,%
(accountability) 96.9 1 , 3 99.9 101, 2 100.2 96.7 Aldehyde Conversion,%
Efficiency (%) 95.0 0 97.1 96.1 94.2 98.5 acetic acid 95.8 6th 95.1 95.1 97.0 92.0 Methyl acetate 1.0 1.0 1.0 0.6 0.9 Formic acid 0.2 0.2 0.2 0.2 0.3 Carbon dioxide 2.5 3.1 3.1 2.0 5.9

^{X In} addition to the products mentioned, small amounts of formaldehyde, methyl formate, carbon oxide, methane and water were formed.

Examples 1 to 20 illustrate the comparison of the oxidation reactions carried out in the liquid phase from acetaldehyde to acetic acid using the following catalysts:

1) Copper (II) acetate alone (Examples 1 to 4)

2) Copper (II) acetate and manganese acetate (Examples 5 to 8)

3) Manganese (II) acetate alone (Examples 9-20).

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ORIGINAL INSPECTED

A comparison of the use of copper (II) acetate alone with the combination of copper (II) acetate and manganese (II) acetate under the same conditions shows that the efficiency of the oxidation of acetaldehyde to acetic acid when using the combination of the salts is somewhat better than the efficiency when using copper (II) acetate alone. On the other hand, a comparison of the combination of copper (II) acetate and manganese (II) acetate shows with manganese (II) acetate alone under similar conditions that the efficiencies of the oxidation of acetaldehyde increase Acetic acid are very similar. This result was confirmed in a three-day test in which a combination of copper (II) acetate and manganese (II) acetate as a catalyst and manganese (II) acetate alone at concentrations of 300 ppm each of copper and manganese in the Reactors compared to 300 ppm manganese alone were used. It was found that in the system, in which the combination of the manganese and copper salts was used, compared to the plant in which the Manganese salt was used alone, the rate of corrosion was higher and the pump seals were different Pumps failed faster as a result of copper deposits.

Examples 21 to 28

Propionic acid was made by oxidation of propionaldehyde

produced in a one-step liquid phase reaction system. A standing, 183 cm long reactor served as the reactor 5.1 cm inner diameter pipe attached to the floor with a flanged plate with connections for the food lines (air and aldehyde). There were several product take-off points on the side of the tubular reactor provided so that the level of the stirred liquid above the air distributor is regulated by the selection of the tapping point could be. The reaction liquid was continuously fed with a centrifugal pump from the bottom of the

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actuator is pumped through a heat exchanger and discharged immediately above the surface of the liquid in the reactor. The amount pumped around was about 125 1 / hour. The reaction temperature was controlled by regulating the flow of cooling water regulated to the heat exchanger on the circulated stream.

The product (both liquid and gas) was withdrawn through a 6.4 mm line on the side of the reactor into a water-cooled (10 ° C.) gas-liquid separator. The gases exited through a chilled water condenser into a pressure regulating motorized valve and were then passed through a dry gas meter. The liquid products were collected, weighed and analyzed by gas chromatography. The residual gas was continuously _{analyzed for O 2} with a polarographic detector and periodically (at intervals of about 15 minutes) analyzed for CO, CO ", N_ and O" by gas chromatography. The concentrations of propionaldehyde and propionic acid in the residual gas were calculated from the composition of the liquid phase assuming ideal behavior.

The liquid feed consisted of a solution of 9o wt .-% propionaldehyde and 1o wt .-% propionic acid, in which the desired amount of manganese (II) acetate or manganese acetate in combination with copper (II) acetate was dissolved. The real one The weight of the liquid feed supplied to the reaction system was determined. The air became that Reactor fed through a Hasting flow meter. Both the Hasting flow meter and the dry gas meter on the residual gas flow were daily with a large

3o soap bubble meter recalibrated.

The conversions and efficiencies in attempts to oxidize propionaldehyde to propionic acid in this single-stage reactor are shown in Tables V and VI. The pressure was 6.55 bar, and than

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ORIGINAL INSPECTED

- 10 -

Oxidizing agent air was used. The height above the air distributor was about 60 cm. The sales were regulated by the amount in which the oxygen was fed to the reactor.

Table V

Oxidation of propionaldehyde as 2 to propionic acid 1 22nd (300 with 1 24 Manganese (II) acetate alone 29 catalyst 27 60 ppm) 19th 60 example 98 21st 96 , 99 23 87 , 98 Temperature, C 87 60 90 , 70 1 60 93 , 02 Oj in residual gas, mol% 6th , 06 4th , 38 19th , 96 2 , 57 Air supply rate,
Moles / hour 4th , 44 3 , 821 87 , 02 1 , 777 Conversion of propionaldehyde
Efficiencies too 100 , 21 98 , 599 93 , 60 97 , 460 Propionic acid 91 , 451 92 , 326 , 535 92 , 889 acetic acid 12th , 667 11 , 59 1, 7th , 15 CO ₂ , 790 , 04 97 , 920 , 19th Carbon footprint,%
(accountability) , 87 r29 92, , 64 , 75 S auer s to ff sales ζ,% , 66 7, r27 Amount of air supplied,
Liter / min. , 00 75

Reactor volume, liters 1.386 1.216 1.083 1.083

In addition to the products mentioned, there were small quantities Ethanol, ethyl propionate, ethyl acetate, acetaldehyde, diethyl ether, 3-pentanone, methyl propionate and 3-pentanol educated.

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ORIGINAL INSPECTED

Table VX

Oxidation of propionaldehyde to propionic acid using a combination of manganese (II) acetate and Copper (II) acetate (300 ppm each of Mn and Cu)

Example 25 26 27 28

Temperature, C 6o 6o 6o 6o

Oj in residual gas, mol% 2 _r oo 1.97 2 _r o4 3, oo

Air supply rate,

Moles / hour -21 _r 74 21.74 25,, 81 32.71

Conversion of propionaldehyde 87.19 87 ,. 18 96 ,. 3 8 97 _r 77

Efficiencies too

Propionic acid 94.546 94.726 90, ^ 378 87.2ο4

Acetic acid 2.787 2.56o 4.621 6.186

CO ₂ 1.515 1.545 3.635 5.399

Carbon balance, % 98.7o 97.92 1o6, oo 1o2.15 (accountability)

Oxygen conversion, % 92.14 92.26 91.81 87.72 Amount of air supplied, 8.86 8.36 1o, 52 13.33 liters / min "
Reactor volume, liters 1-, 17o 1, 17o 1 ^ 256 1.3 86

In addition to the products mentioned, small amounts of ethanol, ethyl propionate, ethyl acetate, acetaldehyde, Diethyl ether, 3-pentanone and methyl propionate are formed.

A comparison of the catalyst combination made of copper (II) acetate and manganese (II) acetate with manganese (II) acetate alone under the same oxidation conditions shows that the efficiency of the oxidation of propionaldehyde increases Are very similar to propionic acid.

Examples 29 to 36

The preparation of valeric acid by oxidation of n-valeraldehyde was carried out in the example 21 to 28

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ORlGfNAL INSFCCTED

described the same single-stage liquid phase reaction system was carried out under the same conditions.

The conversions and efficiencies achieved are given in Tables VII and VII. The pressure was 6.55 bar (Gauge pressure). Air was used as the oxidizing agent and the liquid level above the air distributor was approximately 5o cm.

Table VII

Oxidation of n-valeraldehyde to valeric acid with a catalyst combination of manganese (II) acetate and copper (II) acetate (3oo ppm each of Mn and C u)

example 6o 29 ' 6o 3o 31 6o 6o 32 Temperature, ⁰ C. 3 3 3.51 2 O ₂ in the residual gas, mol% 85 , 72 85 , 72 85.88 88 , 85 O "sales,% 24 , 16 21st , 15 28.49 19th , 75 Air supply rate,
mol / hour 99 , 56 99 , 37 1oo, 68 96 , 95 Carbon footprint,%
(Accountability) , 43 , o1 , 83 Sales of Valeralde- 91 86 95.15 82 hyd,% , 13 , 16 , 54

O , 927 1 O , 931 1 1 , 594 O, 68 O , o27 O , o32 1 O , o65 1o , o1 8th , 71 1 , 61 8th, 13th 17th , 47 7th , 58 7th , 43 17, 6th

χ EFFICIENCY%

Valeric acid 94.872 94.726 92.415 95.424 2-methylbutyric acid o, 431 o, 437 o, 411 o, 432 Butyric acid 2.494 2.489 3.589 2.19o

CO ₂
CO

Supplied air volume, l / min.

Amount of liquid supplied, ml / min.

Reactor volume, 1 1, o83 1, o83 1, o83 1, o83

χ In addition to the products mentioned, small amounts of propionic acid, acetic acid, levulinic acid, c * -Valerolac-

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INSPECTED

- 10 -

clay, methyl ethyl ketone, butanol, butyl valerate, 5-pentanone and butyraldehyde. The degrees of effectiveness are based on the entire C ^ -aldehyde.

Table VIII

Oxidation of n-valeraldehyde to valeric acid with Manganese (II) acetate as a catalyst (3oo ppm Mn)

Example 3_3 3_4 35 36

Temperature, ° C

O ₂ in residual gas, mole% O ₂ conversion,%

Amount of air supplied, mole / hour

Carbon balance,% (Accountability)

Valeraldehyde conversion,% χ degrees of efficiency,%

Valeric acid

2-methyl butyric acid Butyric acid

co ₂

CO

Supplied air volume, l / min.

Liquid feed rate, ml / min.

Depth of air distribution _{5q 5q 5o 5o}

lers, cm

Reactor volume, 1 1, o83 1, o61 1, o61 1, o61

6o , 79 6o 82 6o 8o 6o 2 , 77 2, 76 2, 87 3, o5 88 , 18 88 12th 88 88 87.78 17th , 36 15, 69 19 35 16.78 97 , 49 98 14th 97 24 97.2o 94 , 933 87 266 82, 556 9o, 4o 9o , 222 93, 232 94, 28o 92.834 O , o29 O, 754 O, 975 o, 216 4th , 838 2, o93 1, 961 2.914 1 , 217 ', 258 O, 253 1, 258 O , OO O, 16 O, 1o o, 249 7th , 75 6, 57 8th, 8o 6.84 11 11 16, 11, 57

χ In addition to the products mentioned, there were small quantities
Propionic acid, acetic acid, levulinic acid, c * -valerolactone, methyl ethyl ketone, butanol, butyl valerate, 5-pentanone and butyraldehyde are formed. The efficiency

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- 2ο -

is based on all of the C ^ -aldehyde.

A comparison of the combination of copper (II) acetate and Manganese (II) acetate with manganese (II) acetate alone below Similar oxidation conditions results in the efficiencies of any oxidation process of acetaldehyde

Acetic acid, propionaldehyde to propionic acid and n-valeraldehyde are very similar to valeric acid. The main difference between the two catalysts is in that when using the copper-manganese combination

the presence of copper deposits cause corrosion problems and rapid seal failure different pumps used. These problems arise with the use of the manganese catalysts alone not before. In the presence of copper, cumbersome separation processes are necessary to remove the copper Completion of the reaction to remove from the reaction system.

Examples 37 to 41

These examples illustrate the production of heptanoic acid from heptanal in a one-step process, in which the oxidation reactor consisted of a 91.4 cm long glass tube with an internal diameter of 5.1 cm, with a flanged plate attached to the floor, with connections for insert and product lines and a attached cooler was provided. The reaction temperature was set by controlling the flow of tap water to the heat exchanger regulated by a circulating water flow. The reaction liquid was continuously fed with a Eastern centrifugal pump pumped from the bottom of the reactor through the heat exchanger and immediately above the surface the liquid discharged in the reactor. The pumping rate was about 125 l / h. corresponding to about 1.6 reactor "Passes" per minute.

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The product (both liquid and gas) was added via a 57 cm high "standpipe" with a 6.35 mm internal diameter withdrawn, which adjusted the "stirred" reactor volume to about 1.3 liters. The liquid and gaseous products flowed through a pressure regulating motorized valve and into a water-cooled gas-liquid separator. The gases exited through a water-cooled condenser and flowed through a wet gas meter. The obtained liquid products were distilled in batches to isolate the reaction products.

The reaction conditions and results of these experiments performed in the manner described above using a manganese salt alone (3oo ppm manganese on average) as a catalyst at 6.2 bar (pressure gauge) and 50% oxygen in nitrogen carried out as the oxidant are reported in Table IX. The used Heptanal, which had been obtained from 1-hexene and carbon oxide by the so-called "Oxo" reaction six weight percent 2-methylhexanal. The added to the reactor Catalyst solution contained five wt .-% manganese (II) acetate (or 1.12% by weight manganese), the remainder acetic acid (81.6%) and water.

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Table IX

Oxidation of heptanal to heptanoic acid using manganese (II) acetate as a catalyst (average 300 ppm Mn)

example 37 38 39 40 41 Temperatures, ⁰ C center 80 80 80 80 80 floor 82 81 83 83 83 Bet rates: C ₇ aldehyde, ml / min.
Catal. Solution, " 2OfOO
0.50 16.30
0.42 21, 80
0.54 24.90
0.62 29.90
0.75 Oxidizing agent,
Moles / 1 / hour 10.44 0.58 11.46 12.34 13.62 Mn usage in ppm
in the liquid product 325 330 330 330 345 H ~ O input in% by weight
in the liquid product 0.39 0.39 _Or 39 0.39 0.41 Acetic acid added
in% by weight in liquid product .2.37 2.40 2.40 2.40 2.51 Oxygen use,
Moles / 1 / hour 5.22 4.79 5.73 6.17 6.81 Oxygen conversion,% 89.7 90.7 92.8 90.2 86.8 Oxygen consumption,
Moles / 1 / hour 4.68 4.34 5.32 5.61 5.91

Estimated residence time of the liquid, min.

Cy aldehyde conversion,% Efficiency,%

Heptanoic acid 2-methylhexanoic acid C ₇ ~ acids in total

CO ₂

Hexane

Hexanal

Hexanol

Hexanoic acid

Ester

49 1.8 60 , 2 45 ² 39 , 4 33 i 6th 9C , 36 92 , 96 88 04 87 , 37 80, 81 76 , 34 75 , 47 74, 93 74 , 03 76 13th 3 , 70 3 , 43 3, 97 4th , 40 4, 94 79 , 60 79 , 55 77 68 78 , 69 80, 70 O , 75 0 , 69 0, 53 0 , 48 0, 37 2 , 93 2 , 43 2, 30th 2 , 43 2, 95 4th , 43 4th , 42 6, 40 6th , 47 5, 03 2 , 72 2 , 72 2, 62 2 , 75 1, 70 1 , 42 1 , 84 1, 19th 1 , 24 1, 96 3 , 38 3 , 55 3, 20th 3 , 24 2, 02 2 2 2, 2 2,

130009/0836

ORIGINAL INSPECTED

- 2

χ In addition to the products mentioned above, small amounts of high-boiling compounds, lactone, keto acid, succinic acid and propionic acid were formed. The degrees of effectiveness are based on the entire C _{7 aldehyde.}

Examples 42 to 47

Table X shows the conversions and efficiencies obtained in another series of experiments using hexanal in a single stage reactor in the manner described in Examples 37-41 of manganese (II) acetate alone (3oo ppm manganese on average) as a catalyst at 6.2 bar with 5o% Oxygen was oxidized to heptanoic acids in nitrogen as the oxidizing agent. The catalyst solution fed to the reactor contained 5.39% by weight of manganese (II) acetate (1.21% by weight of manganese) dissolved in heptanal.

130009/0836

ORIGINAL INSPECTED

Table X

oxidation from Heptanal too Heptanoic acid using 42 43 44 45 Manganese (II )-acetate as a catalyst 67
62 60
61 63
65 71
70 Example no. 46 47 Temperature, ⁰ C: center
floor CM VD
VD VD 69
73

Branched aldehyde im

Insert,% 3.75 3.75 5.71 6.76 5.70 7.76

Bet rates:

<*> C ₇ aldehyde, ml / min. ο catalyst solution, ml / min.

Oxidizing agent, mol / l / h

-Use in p liquid product

Mn usage in ppm im

21.50 18.30 16.70 15.05 15.80 14.20 0.47 0.40 0.36 0.33 0.36 0.32 4.63 4.63 4.63 4.63 4.47 4.48 280 270 265 270 , 290 280 2.27 2.27 2.27 2.27 2.17 2.17 98.8 97.4 96.6 95.7 97.3 96.9

ω oxygen input, mol / l / h cn

Oxygen conversion,%

■ oxygen consumption,
Moles / 1 / hour 2.24 2.21 2.19 2.37 2.11 2.11

Estimated residence time

of the liquid, min. 46 54 59 65 62 69

C ₇ aldehyde conversion,% 63.8 70.6 75.9 83.3 82.5 87.8

Table X (cont.) Example 42 43 44 45 46 47

efficiency,%

Heptanoic acid 87.61 88.00 86.84 80.89 82.33 77.37

2-methylhexanoic acid 2.80 2.80 3.66 5.11 3.44 5.92

Total C ₇ acids 90.40 90.80 90.50 85.99 85.77 83.29

CO 0.24 0.24 0.34 0.50 0.36 0.63

^ J CO ₂ 0.55 0.63 0.78 1.01 0.97 1.15

° hexane 3.28 3.36 2.72 4.03 3.91 5.38

ο hexanal 1.24 1.29 1.37 1.59 1.05 1.95

Hexanol 0.44 0.52 0.51 0.78 1.03 1.85

Hexanoic acid 0.96 1.13 1.2o 2.93 x 1.5o 2.41

Ester 1.18 1.16 o, 91 1.10 2.85 1.65

High-boiling compounds 1.18 0.34 0.96 0.80 0.04 0.00

In addition to the above products, small amounts became higher boiling points Compounds, lactone, keto acid, succinic acid and propionic acid are formed. The degrees of effectiveness are based on the entire C ^ -aldehyde.

Examples 48 and 49

The oxidation reaction was carried out in a single-stage reactor as described for Examples 37 to 41 from heptanal to heptanoic acid using an average of about 6oo ppm manganese alone (as manganese (II) acetate) carried out as a catalyst. One was stirred in the 5.1 cm diameter glass tube serving as the reactor Maintained liquid height of 61 cm with a stirred liquid volume of 1.24 liters. Of the

10 pressure was kept at 6.2 bar. A mixture that

Containing 50 wt% oxygen in nitrogen was used as the oxidizing agent and passed through a frit 316 stainless steel distributed. The catalyst was added to the reactor in the form of a solution of 10% by weight of manganese (II) acetate (2.24% by weight of Mn) in heptanoic acid fed. The conversions and efficiencies in this series of tests are given in Table XI.

Table XI

Oxidation of heptanal to heptanoic acid using manganese (II) acetate alone (average 6oo ppm Mn ⁺⁺ )

Example 48 49

Temperatures, C .:

12.7 cm from the floor 65 65

4o, 6 cm from the floor 62 62

Catalyst solution fed, ml / min. o, 31 o, 25

Calculated catalyst concentration ppm 6oo 56o Oxidizing agent fed in, mol / 1 / hour. 4.2o 3.84

Oxygen in residual gas, mol% 4.4 4.5

Oxygen conversion,% 94.1 94, ο

Oxygen consumption, mol / 1 / hour 1.88 1.72

Conversion of 0, - aldehyde 89, o 91.1

χ efficiency,%

Heptanoic acid 82.78 81.47

130009/0836
ORIGINAL INSPECTED

5, o9 5, o3 87.87 86, 5o o, 33 o, 3o 1, 00 1.15 2.48 2.33 1, 24 o, 61 0, 6o o, 72 2.21 2.99 2.69 2.66

- 27 -

Example 48 49

2-methylhexanoic acid total C, -acids CO

CO ₂

Hexane plus hexene hexanal

Hexanol

Hexanoic acid

Ester

n In addition to the above products, small amounts of high-boiling compounds, lactone, keto acids, succinic acid, glutaric acid and dehydrated

Aldol dimers formed. The degree of efficiency lies in the ge-j all C_-aldehyde is based.

Examples 5o to 56

Using the same single stage reactor and using the same conditions as in the Examples 37 to 41 a series of experiments for the oxidation of heptanal to heptanoic acid was carried out, wherein a combination of copper and manganese salts in a molar ratio of 1: 1 was used as the catalyst. The catalyst solution used in the reaction contained 3.74% by weight of copper (II) acetate (1.19% by weight of Cu) and 5.31% by weight manganese (II) acetate (1.19% by weight manganese) in heptanoic acid. The one from a glass tube 5.1 cm in diameter existing reactor was kept at 6.2 bar. A mixture of 50% oxygen served as the oxidizing agent in nitrogen. The conversions and efficiencies obtained in these experiments are shown below in Table XII called.

130009/0836

Table XII Oxidation of heptanal to heptanoic acid in a one-stage reactor using a Catalyst combination of copper (II) and manganese (II) acetate

Example 50 5J 52 53 54 55 56_

Height of the stirred liquid,

cm 63.5 63.5 61 61 61 61 61

Volume of stirred

Liquid, liter 1.30 1, 30 1.24 1.24 1, 24 1, 24 1.24 , 3 I. _ ^ Temperature, C, 12.7 cm from the floor 63 66 62 62 67 75 76 , 17th ro
co co
ο 16 inches from the floor 67 70 66 66 70 71 80 I. O % 2-methylhexanal in the aldehyde 7.8 7.8 5.7 6.3 6.3 6.3 6, (O Supplied catalyst solution,
ml / min. 0.35 0.33 0.30 0.22 0.17 Q, 17th 0, 3836 Calculated catalyst concentrations
tration, ppm Mn and Cu each 290 260 250 *
270 255 250 280

Feed oxidizing agent, mol / l / h, calc. from N ₂ in the residual gas

Oxygen in residual gas, mol%

Oxygen conversion,%, based on N ₂ in the residual gas

Oxygen consumption, mol / l / h, based on N ₂ in the residual gas. Estimated residence time of the liquid, hours

C ₇ aldehyde conversion,%

4th , 43 4th , 72 4th , 13 3 , 61 3.62 4th , 22 4th , 49 CO 3 , 0 3 , 3 3 ,8th 4th , 4 3.0 3 , 0 2 , 4 σ
fsj 96 , 6 96 , 2 95 , 2 94 , 3 96.1 95 , 9 96 ,8th CO
O 2 , 12 2 , 25 1 , 87 1 , 62 1, 66 1 , 93 2 , 07 1
75 , 3 ■
, 4 1
78 , 4
, 7 1
81 , 4
, 0 2
90 , 0
,1 2.5
93.0 2
96 , 5
, 7 2
94 , 5
,1

Table XII (cont.)

example 50 51 52 53 54 55 56 I. efficiency,% to Heptanoic acid 85.32 85.69 87.16 85.76 81, 56 80.05 78.00 I. 2-methylheptanoic acid 7.04 6.88 5.52 5.37 5.30 4.97 4.90 Total Cy acids 92.36 92.57 92.68 91, 13 86.86 85.02 82, 90 CO 0.30 0.37 0.26 0.25 0.26 0,? 6 0.39 co ₂ 0.46 0.56 0.49 0.75 1.41 1, 92 2.23 Hexane plus witches 1.41 1.48 0.70 0.75 0.56 0.57 0.61 Hexanal 0.81 0.93 0.87 0.97 1.35 1.31 1.42 Hexanol 0, .16 0.17 0.00 0.14 0.39 0.00 0.00 Hexanoic acid 1, 00 1.23 1, 38 2.19 3.28 2.98 3.81

In addition to the above-mentioned products, small amounts of high-boiling
Compounds, esters, lactone, keto acid, succinic acid, glutaric acid,
dehydrated aldol dimers. The efficiency is the whole
C ₇ aldehyde.

Examples 37 to 56 allow a direct comparison of the oxidation of heptanal to heptanoic acid using a manganese salt as catalyst alone and a catalyst combination of manganese and copper salts. The use of manganese salts alone as oxidation catalysts for the production of acetic acid from acetaldehyde, propionic acid from propionaldehyde and valeric acid from n-valeraldehyde results in high carbon efficiencies to acid with high aldehyde conversions. It has been found, however, that with increasing carbon content of the aldehyde, the carbon efficiency to acid decreases rapidly at high aldehyde conversions. For example, the carbon efficiency of heptanal to C_ acids was 90 to 91% up to an aldehyde conversion of about 75% and quickly fell to 86% at an aldehyde conversion of 82%. The low conversion of heptanal at high carbon efficiencies to acids per pass (70 to 75%) with recovery of unreacted aldehyde (by distillation) requires a cycle process in order to achieve the best overall yields. The use of the combination of manganese and copper salts for the oxidation of heptanal to heptanoic acid results in carbon efficiencies to C ₇ acids in the range from 90 to 93% with aldehyde conversions of 80 to 90%. The results with the combination of manganese and copper salts in the oxidation of heptanal are significantly better than the results obtained with the use of a manganese salt alone. The use of the combination of manganese and copper salts enables a two stage reactor to be used to further convert the small amount of unreacted aldehyde to the desired heptanoic acid without the use of aldehyde recovery and the use of a loop system. This is illustrated by the following examples.

130009/0836

- · ■ ι -

Examples 57 to 59

These examples illustrate that heptanal can be oxidized to acids to heptanoic acid at high carbon efficiencies using a catalyst comprised of a combination of manganese and copper salts in a two stage reactor with total aldehyde conversions of about 94 to 98%. The two-stage reactor consists of two reactors connected in series in the form of 244 cm long glass tubes 5.1 cm in diameter, with heptanal in the first stage in the range from about 80 to 86% at a reactor height of 116.8 cm (2.37 1) and in the second stage the reaction product from the first stage is fed to a reactor height of 76.2 cm (1.54 l) for further conversion of the unreacted aldehyde until a total aldehyde conversion of about 95 to 98 % is reached. The following reaction conditions were used in the two stages: The pressure was 6.2 bar. The oxidizing agent used was a mixture of 50% oxygen in nitrogen, which was distributed in the first stage by a 432 μm capillary distributor and in the second stage by a 179 μm capillary distributor. The catalyst solution contained 4.45% by weight of manganese (II) acetate (1.0% by weight of manganese) and 3.14% by weight of copper (II) acetate (1.0% by weight of copper) in 5 heptanoic acid (density 0.918 g / ml.) and was only fed to the reactor of the first stage. The circulation rate was 1.98 l / min.

Using this procedure, high total carbon efficiencies to heptanoic acid were achieved without the use of recycle operation, as shown by the results in Table XIII, which lists the total conversions and efficiencies achieved in these experiments. The first stage conversion results were estimated on the basis of the C ₇ aldehyde content.

130009/0836 ORIGINAL INSPECTED

Table XIII

Two-stage oxidation of heptanal to heptanoic acid using a catalyst combination of manganese (II) acetate and copper (II) acetate

Example '57 58 59

Temperatures, ⁰ C
12.7 cm from the floor
(1st level) (2nd level) (53) (53) (53) (53) (53) (52)

16 inches from the floor

(1st level) (2nd level) (52) (53) (50) (53) (51) (52)

C ₇ aldehyde added,

ml / min. 26.63 25.53 25.30

Catalyst solution fed, ml / min. o, 7o o, 68 o, 69

Catalyst concentration,

ppm per 26o 26o 265

Supplied oxygen,

mol / hour, based on

Nitrogen in residual gas 5.78 6, o4 6.43 oxygen in residual gas,

mol /% ² , 4 ³ '° ³ ' ¹

Oxygen conversion,%, loading

moved to nitrogen im

Residual gas 9o, 488.1 87.8

C ^ aldehyde conversion,%

First stage 81 86 86

total 95.2 96.1 96.8

χ efficiency,%

Heptanoic acid 83.72 82.6o 82.07

2-methylheptanoic acid 4.34 4.41 5, o5

C _? Total acids 88.06 87, o1 87.12

_co o, o7 o, 1o o, o7

_c0 o, 52 o, 7o o, 76

Hexane, hexene o, 78 o, 67 o, 71

Hexanal 1.11 ¹ '° ^{9 1} ' ¹¹

Hexanol- o, 2o o, 2o o, 22

Hexanoic acid 2.16 2.54 2.81

130009/0836

ORIQ / NAL INSPECTED

Total yield of C ₇ acids ■

from heptanal,% '83.8 83.6 84.3

χ In addition to the products mentioned above, small amounts of esters and light ends were formed. The degrees of effectiveness are based on _{the entire C 7 aldehyde.}

Examples 60 to 62

The experiments were carried out under slightly different reaction conditions than in the case of Examples 57 to 59 using carried out the same apparatus, but using stainless steel frits as a gas distributor were used in each stage. In the first stage reactor, the height of the stirred liquid was 58.4 cm and its volume was 1.18 1. In the second stage, the height of the stirred liquid was 52.1 cm and its volume 1, o6 1. Both stages were kept under a pressure of 6.2 bar (gauge pressure). 50% oxygen in nitrogen was used. The catalyst solution (density 0.822 g / ml) contained 3.74% by weight of copper (II) acetate (1.19% by weight of copper) and 5.31% by weight of manganese (II) acetate (1.19% by weight of Mn) dissolved in heptanoic acid. The catalyst solution was only added to the first stage and calculated as amounts in the second stage.

The conversions and efficiencies of the two-stage oxidation of heptanal under the above conditions are given in Table XIV.

130009/0836 ORIGINAL

Tabel

XIV

Two-step oxidation of heptanal to heptanoic acid using a
Catalyst combination of manganese and copper

example 1.
step Calculated catalyst con
centration, ppm Mn and Cu each 3 1 80 6o Total
velvet 1.
step 40 61 Total
velvet 75 1.
step 50 62 Total
velvet 81 66 Supplied oxidation
medium, mol / 1 / hour, be
calculates from N "in the residual gas 7th 1 29 ■ 2.
step _ 66 33 2.
step 66 34 2.
step Temperature, C
12.7 cm from the floor 65 Oxygen in residual gas, mol-? Oxygen conversion,%, based
to N "in the residual gas 9o 89 65 - 65 65 - 8th 65 66 - , 7 16 inches from the floor 11 Oxygen consumption,
mol / 1 / hour, based on N ₂
in the residual gas , 44 65 _ 13, , 87 65 - , 2 13, _P 82 65 _ , 25 C ₇ aldehyde added,
ml / min. O, estimated dwell time of the
Liquid, hours , 6 - - O, , 4 _ - O, , Q - - Admitted catalyst
solution, ml / min. Cy aldehyde conversion,% , 5 - _ - ,8th _ '- ,1 - ,O - - , 48 29o 4.61 3 , 76 285 4, 3 , 78 295 4, , 7 - 7th , 4 - 6th , 4 _ - ,1 13.1 82.3 91 , 7 3.9 94, 92 , 3 5, ο 93 - 1, 81 1 - 2 1 - 2 _{11 |} - 1 - 1 - 1.8 98.7 84, 1.6 97 84 1.3 97 9, ο 13, ο 12.7

Tabel

XIV (cont.)

Two-stage oxidation of Hepfeanal to heptanoic acid using a catalyst combination of Manganese and Kuofer

example 1. , 59 60 Total , 29 1 . 61 Overall 1 . 58 86.22 62 Overall 4-
(^ , 52 2. velvet , 15 Stu 2. step 57 5.72 2. sam , 11 step , 44 fe level 15th 91, 94 step , 68 κ efficiency,% step , 33 83 , 32 85 82, 29 o, 39 85 , 39 Heptanoic acid , 55 - 5 , 97 5, 94 5, 77 o, 38 - 5 , o7 2-methylhexanoic acid 84 , 13 - 88 , 83 91 87 88 95 1, 84 - 91 , 37 C -, - acids in total 5 , o3 72.2 0 , 00 0, 81 63.6 ο, 91 1, 00 84.9 0 , ' CO 9o , 24 - 0 , 22 0, 32 '- ο, 22nd 0.00 - 0 , o2 co ₂ 0 , 86 - 0 , 91 1, 36 ο, 5c 1, 29 - 1 , 00 Hexane plus witches 0 - 1 0, 76 ο, - 1 , o9 Hexanal 1 - 0 0, 91 ο, - 0 , 4o Hexanol 1 - 1 1, 24 2, - 1 Hexanoic acid 0 - 24 - 1

In addition to the products mentioned above, small amounts of high-boiling compounds, light ends, esters, pentanoic acid, butyric acid, propionic acid, acetic acid, lactone, keto acid, succinic acid, glutaric acid and dehydrated aldol dimers * The degrees of effectiveness are based on the entire C ^ -aldehyde.

Examples 63 to 68

These examples illustrate that nonanal can be produced using a combination of manganese and copper salts very effective as a catalyst in a two-stage reactor with total aldehyde conversions of about 91 to 97% can be oxidized to acids with high carbon efficiencies. The same two stage reactor as in the case Examples 57 to 59 for the oxidation of heptanal to heptanoic acid were used. It consisted of zv: ei one behind the other - glass tubes with a diameter of 5.1 cm, wherein the reaction medium in the first stage reactor at a height of 116.8 cm (2.37 liters) and the reaction medium was maintained at a height of 76.2 cm (1.54 liters) in the second stage reactor. The pumping rate was 1.98 l / min. The catalyst solution used contained 2.81% by weight of manganese (II) acetate (0.36% by weight of Mn) and 1.98% by weight of copper (II) acetate (0.3% by weight of Cu) in one Mixture of 43% by weight acetic acid and 52.2% by weight nonanoic acid. The acetic acid served to dissolve the Accelerate manganese and copper salts. Both stages were kept under a pressure of 6.2 bar (gauge pressure). 50% oxygen in nitrogen was used as the oxidizing gas.

The results of these tests are given in Table XV. The sales of the first stage were based on the Cg aldehyde content is determined.

130009/0836 ORIGINAL / KfSPECTED

Table XV

Two-stage oxidation of Nonanal 63 to nonanoic acid using a 66 67 68 Catalyst combination of manganese (62) (63) and copper (53) (54) (52) (53) (52) (53) example (60) (63) 64 65 (51) (54) (51) (53) (51) (53) Temperature, ° C
12.7 cm from the floor
(1st level) (2nd level) 23.0 (63) (60) (53) (53) 25.6 24.6 25.6 16 inches from the ^ floor
(1st level) (2nd level) 1, 27 (61) (60) (51) (53) 1, 32 1, 30 I.
1.36 " 130 C ₇ aldehyde added,
ml / min. 200 25.3 28.6 185 190 I.
190 009 Admitted catalyst
solution, ml / min. 2.4 1, 36 1.51 2.3 2.3 2.3 cn Catalyst concentration
ppm Mn ⁺⁺ and Cu ⁺⁺ each 5.57 195 190 6.11 5.82 5.98 CJ
CD Acetic acid concentration,
Wt% 4.4 2.3 2.2 4.4 4, ο 4.3 Supplied oxygen,
mol / hour, based on
Nitrogen in the residual gas 5.37 5.77 Oxygen in the residual gas,
mol /% 4.4 3.3

Oxygen conversion,%, be CO

moved to nitrogen in the O

Residual gas 82.2 82.6 86.8 82.3 84, ο 82.9 N>

Cq aldehyde conversion,% ^ j

First stage certainly n.b.x n.b.x 75 8th 85 3 87 ,1 84 , 6 All in all 97.2 96, ο 9o, 95 96 96 χ n.a. = not

Table XV (cont. )

Two-stage oxidation of nonanal to nonanoic acid using a catalyst combination of manganese and copper

Example 62! 6J 65 66 67 68

χ Efficiency,% nonanoic acid 2-methyloctanoic acid Cg acids total - ¹ CO

O CO ₀

_o octane plus octene

^ Octanal

O octanol

c *> Octanoic acid 2.53 2.49 2.21 2.37 2.52 2, o1

χ In addition to the products mentioned above, small amounts of light ends,
Esters and dehydrated aldol dimers are formed. The degree of effectiveness is the
total Cg aldehyde.

rs> co ^ a ο ο

82, 83 83, 15th 82, 8o 84 , o3 83 , o7 85 42 3, 48 3, 52 3, 55 3 , 19th 4th , 06 3, 1o 86 31 86 67 86 35 86 , 21 87 , 13 88 52 O, o8 O, o7 O, OO O , OO O , 00 0, 00 O, 76 O, 67 O, 57 O , 75 O , 7o 0, 63 1, 31 1, 49 1, 9o 1 , 46 1 , 5o 0, 65 1, 6o 1, 69 1, 64 1 , 66 1 , 77 1, 36 O, 53 O, 62 O, 7o O , 59 O , 5o 0, 2o

Claims (4)

PATENT LAWYERS Dr.-Ing. von Kreisler t 1973 Dr.-Ing. K. Schönwald, Cologne Dr.-Ing. K. W. Eishold, Bad Soden Dr. J. F. Fues, Cologne Dipl.-Chem. Alek von Kreisler, Cologne Dipl.-Chem. Carola Keller, Cologne Dipl.-Ing. G. Selting, Cologne Dr. H.-K. Werner, Cologne Ke / Ax DEICHMANNHAUS AM HAUPTBAHNHOF D-5000 COLOGNE 1, August 4, 1 98o CELANESE CORPORATION, 1211 Avenue of the Americas, New York, N.Y. 10017 (U.S.A.) claims 1. / Catalytic process for the production of organic - ^ see aliphatic monocarboxylic acids with 6 to 9 C atoms by oxidation of the corresponding aldehydes of the acids, characterized in that the catalyst a combination of acid-soluble manganese and copper compounds used in which the The molar ratio of manganese to copper is in the range of about 5: 1 to 0.5: 1. 2. The method according to claim 1, characterized in that heptanoic acid is produced from heptanai. 3. The method according to claim 1, characterized in that nonanoic acid is produced from nonanal. 4. The method according to claim 1 to 3, characterized in that there is used as copper and manganese catalysts Copper (II) acetate and manganese (II) acetate in a molar ratio from manganese to copper in the range of about 3: 1 used up to 1: 1. 130009/0836 Telephone: (0221) 131041 · Telex: 8882307 dopa d ■ Telegram: Dompatent Cologne