DE2627230A1 - BRASS CATALYST AND ITS USE FOR DEHYDRATING PRIMARY AND SECONDARY ALCOHOLS - Google Patents

Description

uZ: L 747 (Vo / Ra / H)
Case: 363Ο

ASHLMD OIL, INC.

Ashland _? Kentucky. V.St.A.

"Brass catalyst and its use for the dehydrogenation of primary and secondary alcohols"

Priority: June 18, 1975, V.St.A., Sr. 587 893

The Use of Brass "in the Dehydrogenation of Isopropanol and sec-butanol to acetone and methyl ethyl ketone is "known; see Faith, Industrial Chemicals, John Wiley, 3rd edition, 1965 pages 23 and 51 '+.

In these reactions, the brass catalyst can be different Contain copper and zinc and other elements and it is usually used in solid form. Of the Brass Kata'17 / sator can either be in compact form or on an inorganic carrier is present; η.

Brass catalysts enable the production of carboxyl compounds from alcohols in high selectivity towards other

609852 / 10S7

their possible products, such as olefins. You are beyond very stable and can be used for a wide variety of alcohols. It is described in US Pat. No. 2,829,165 that solid brass containing catalysts also in liquid phase used for the conversion of alcohols into carbony compounds can be.

It has long been known that the specific surface area of a solid catalyst has a decisive influence on its Has activity. Various methods have been used to increase the surface area of catalysts. In the GB PS 624 035 we.d the treatment with acids described in the U.S. Patent 3,554,930 describes the reduction and / or decomposition of metal salts on a carrier and in US Pat. No. 2,475,965, the prepressing of copper oxide in the shaped catalyst part with subsequent Reduction of the oxide to elemental copper.

The invention is based on the problem of catalysts made from brass powder or from powdered mixtures of copper and zinc, which enable the conversion of alcohols to aldehydes and ketones with high selectivity. These The object is achieved by the invention.

The invention thus relates to that characterized in the claims Object.

Brass powder, e.g. an alloy of copper and zinc, or a powdery one

609852/1057

Mixture of copper and zinc used in the specified proportions will. The powder mixture can optionally contain up to 25% tin. A proportion of copper to zinc of 80:20 is particularly preferred. The particle size in the invention powders used ranges from 0.0025 to 0.25 cm. The particles are generally spherical in shape.

The powder is pressed and sintered using the methods customary in powder metallurgy. The powders are in a

2 form at pressures of 140 to 14,000 kg / cm, preferably of

5600 to 8400 kg / cm pressed into the desired shape. If necessary, an organic binder can be mixed with the metal powder in order to increase the adhesion of the particles during pressing. Organic binders that can be used are, for example, graphite or high molecular weight organic acids. The sintering of the mold parts is preferably carried out under inert gas at temperatures of 820-1440 ⁰ C.

In the process according to the invention, the catalysts can be produced in any shape, for example as balls, cones, cylinders, saddles or rings. According to the invention shaped catalysts have a large surface area and a porous structure in contrast to the usual compact ones Catalysts with a small surface area and a non-porous structure. Annular shaped catalyst parts are particularly preferred.

The catalysts according to the invention can without prior activation with high effectiveness for the dehydration of alcohol

6098 5 2/1057 ^J

pick up the corresponding carbonyl compounds used will. Primary alcohols are dehydrated to aldehydes and secondary alcohols to ketones. It can be aliphatic ^, cycloaliphatic (naphthenic) and aromatic alcohols are used will. For example, from "" / methyl ethyl ketone becomes from Cyclohexanol and cyclohexanone from 1-phenylethanol and acetophenone obtain.

The results achieved with the catalysts of the invention are summarized in Table I. In all of the experiments in Table I, the catalyst contains 80% copper and 20% zinc. to a corresponding brass powder was used in its manufacture

a pressure of 700 kg / cm pressed in a ring shape and then sintered ^{at 1150 0 C for about 4 hours.} It is not necessary to activate the catalyst.

The dehydration is done in a vertical position in a heater attached reaction vessel made of corrosion-resistant steel with an inner diameter of 2.5 cm and a length of 127 c carried out. The reaction tube consists of a preheating zone, followed by a 53 cm long catalyst zone and one Kachheizzone. The reaction space can through various inlet openings with nitrogen for purging, with hydrogen to reduce the oxide skin on the catalyst or for regeneration of spent catalyst and be charged with alcohol. The alcohol is taken from a calibrated vessel for loading and into the reaction vessel with a Lapp dosing pump fed in. The connections emerging from the reaction vessel

^L 609852/1057

fertilizers are condensed in a water-cooled cooler. the Liquid products are collected, the escaping gases are measured with a gas burette. The values obtained are in summarized in Tables I and II.

609852/1057

Example 1

Major cut

temperate. ⁰ O

Stun

the

Yield ^, _% by volume

table I.

MÄK,

SBA, % ■

HpO,

unknown

Products

IHSV

CD STl

a b c d e f

g __2

a b c d e £

Example 3 abcde

li a

b c d e

449 458 459 459 458 457 458

300 341 375 405 413 451

437 447 442, .470.

285-328 375 -. 402 ... ... 478 519

14 25 38 49 51 55

3 4 5 6 6.7

■ 4 5 6

2 3 4 5 6 7 p

87.4 85.5 86.4 85.8 86 ', 82.8 83 ₇ 7

100.0 97.0 S9.0 81.0 83.3 80 _r 2

82.0 87 ', 86.0 88.8 88 _; 3

100.0 97.5 92.9 90; 87.7 81.9 76.3

94 ,'5 93.3 92'8 93.1 92.3 92.7 92.8

9.2 34.8 70 0 87.8 91.0 91J2

.92.0 93.8 89.1 86.2

84.5

1.71

18.2 60 6 87 2 94 4 95.1 92'6

h ⁷ 2.3

1 _? 5 21 2 1

89.7 63.4 26 '. 5 6.8 3.2

19th

1.8. 1.8 6 5 10 0 9 _T 7

98.3 81 4 39.4 10.3

0.7
1.3
07

11

09

2.5

13th
1.0
0.6

1.8
2.1
2 _; 4th

3 ₇ 4 3 _; 7 42

39 4.5

4.2 4 _; ^r 5

18 3.5 54 5.8 6 _; 9

3 _; 7 2 9 3; 4 3.2

5 ₇ 0

0.4

2.5

2 4 2 9-5.0

2 2 2 2 2 2 2

2 2 2 2 2 2

3 4 5 6

3.

Example 5

a
b
c
d
e

Average euro er at.
⁰ G

289

358
401
444
480

Table I (continued)

, Hour.

the '

Yield, YoI %

CHEESE,

SBA,

3.5 4.5 5 5 6.5

100 _T 0 92.3 88.2 85 ^ 0 84'.8

⁴ I ¹ 48 3

84.4 95.1 94 _r 8

95.7 51 JO 12.7

unknown

Products

0.3
0.7
1.9

3 ^? _r 4

LHSY

4 4 4 4 4

, Ex. 6th

CjO CO

a
b
c

297
346
397
428

490 "'

2 3

5.7 6.7

100.0 93.7 89.4 87 7 80 _; 8th

13.1 47.3 85.3 94 4

94 4

.86.5 51.8

¹ ^?

0.4
1.0
0
18th
3.9

5 5 5 5 5

a 405 2

b "'" 381 j 4

c 397 "... 6 ■

d "" 397 "■ 6.3

Loading shut down,

c 395 10.3

f 396 "· 12.3

82.1 81.4 85 9 84.6

16.1 x 17.3 11.7 13.8

93.1
Rinsed with Έ £ for 15 hours at 397 ° C

81.8 82.4

16.1 15.8

¹ I ⁹
lj2

1.2

5 5 5 5

5 5

Ex

a 409 .4 100.0 b 408 6th 100 _r 0 C. . 410 ..... 13th 99.9 . d · '408 21 99.8 - "409" " 29 , 99.8 f ____40S ZO 1.00J.O.

: 6.86

8.92 35.3 44.4 40.1 ■ yx ■

92.8 90.9 64.5 55.4 59.6

6 6 6 6

6 .6 ..

NJ GO O

Table I (continued)

Example 9

a
b
c
d
e
£

sp.

10

a
b
c

Average hour, temperat. the

3-84 389 390 396 393 397 397

408 430 482 490

Yield,
VoI %

H ₂ O,

87.8
95 _r 8
98 _t 4
95 _T 8
96 _T 0
96.0
99 _? 1

80.0
92.2
91.1
91 Jl

45.6 47.8 49.1 48.4 39.1 43.2

45; 7th

47.5 78.1 90.1 98 Jo

53.6 52.0 50.7 51.5 60i5 56.5 540

unknown

Products

0.8 0.2 0 _r 2 0.2 0.4 0.3 0 ₇ 3

0 _; 3

2, ^r 7 0.3

IHSV

6 6 6 6 5 5 5

5 5 5 5

K) CO O

Table II

Average temp., ° C

hours

yield
VoI%

SBA, stranger
HpO, products

BeisD. 11

374
454

Example 12

With
34.0
338
33 ^l 8
339
224
230
23.4
214

, 341
-. '341
341
__340

at

ό
6th
9

510 ° 0 regenerated
2
4th

40.5

340

6th
7th
9

11
13th
14th

4th
6th
7th

24
26th
28

50.0
55.2
55.0
89.5
97.3
96.4
96.4

56.8

55.9
54i5
75 ^ 2

7o; o

68.1

44 _T 7
5.0

31.5.
31.8.
33 _r 0
32 _? 9

81.59
76.49
72.71
j 36
61.42
61.12

36.0 91.9

38.9

40.3

44.0

45 _f 6

100

100

100

100

13.94 18 J 43 20.55 29jl8 52.07 32 _? 72

Example 13 ':

285

286

284

Γ285 "

75.0 · 2.2 97.8

70.6 x 2.3 97.7

• 11 66.8: 1.7 .98 3

* '75j0 ./ 1.6 98.4 ■

Catalyst regenerated; in the following 4.9 a'tü pressure

1295
1293

) 345

80.0

younger \

, 46

67.8

61.7

the. Atmospheric pressure
S4 _? 7th

16.2
34.4
51.5

si ,:

S8 ₇ 1 35.2

14th

46.8

. 72.7 13.0

24.2
18.3
3
14.9

3.10
3.45
5.24
4; 36
3.96
4 ₇ 10

l _r 5

4; s

23 ₇ 5

9.8

2.1
1.0

6 _; 4th
31

5.4
6th
6.3
6.7

1.36
1.63
50
2.10

2 ', 55
2 ₇ 06

1-2

2.7

3.5

o, 7

0.5

WHSY

1 1

1 1 1 1 1 1 1 1

2 2 2 2 2 2

2 2 2 2

2 2 2

2 2

Table II (porting)

Average
temoerat

hours

Yield, YoI %

SBA,

H ₂ O,

unknown
'Products

Ex.

330

315 ■

315
324
334 \

334 \
V

333 ι
333. '

335 "

340

j
344 Ί

Ί- 346;

4th
■ ■ WHSV on

7th
9

11
WHSV on 2

13th
■ "15

17th
-WHSV on

19th
- WSHV on

21
WHSV '

60.0

61.1 A- increased

66.3

64.2

63.9

60.0 lowered

48.0

42 _; 2

46.0 5 'increased

62.4, 6 increased

73.2 8 increased

69.8 two-phase produfct ·.

77.69 11.86 7 _T 08 3.37

77.68 8.84 8.82 3.86

50.52 33.18 13 ^ 21 3.09

47 _; 92 33.16 13 _? 29 5.14

Two-phase product

25.98
20.37
18.27

52.27
62 ₇ 38
., 97

.14 _r 99 6.62

10.14

7.10

10.02 6.74

VHSV.

2 2

4 4, 4 4

2 2 2

.4 '6 8

Example \ 15

353 _ ".
329 Y__
327

328, -327 _. "- 327

328
328

4th
6th
8th

10
11

• 67.8 77.1 76 5 74.1 73.0 74.0

V / .HSV on. A- 'increases 13 80 _r 0

15th 77.2 80.79
45.99
• ■ 46.27 ·
45.56
47.95
44 _; S1

34.26
32.43

42.29

41.54
42.20
39.54
42.54 '

54.86

55; 97 ...

12.69. ■ 6 _T S2
4.45

7.07

• l \ 06

7.78 _BC

7'l3 - \ ^y

7.98:

5.90
6.79

5.13
■ 4 47

4th year 97

4.98
81

2 2 2 2 2 2

4 4

262723Q

In Tables I and II, LHSV means liquid hourly space velocity, defined as the volume of liquid Feed per volume of catalyst per hour. WHSV (weight hourly space velocity) means the weight of the liquid feed per weight of catalyst per hour. MÄK means methyl ethyl ketone, SBA means sec-butanol and Percentage by volume means the yield in the form of liquids, i.e. as methyl ethyl ketone, sec-butanol, water or unknown Liquid recovered portion of the feed.

Example 1 shows the effectiveness and the stability of the catalyst, with uninterrupted operation for 55 hours. From-. The amount of methyl ethyl ketone only decreases by 2 percent by weight after 55 hours. The overall yields in Experiment 1 are relatively low because the liquid products were collected at room temperature. By collecting at 0 ^° C., the volume yield is increased to over 90% .

Examples 2 and 6 show the effect of temperature and tree speed on the conversion of sec-butanol to methyl athylketoni ^ J ^ h ^ O ^ bell-e - ^^ the conversion -__

development at a space velocity of 2 at 406 ⁰ C and at a space velocity of 6 at 4-86 ⁰ C.

Examples — 7 to 1O ^ show the results of long-term events - "^" - looking at space velocities of fT ^ raidö .. The catalyst shows during these extended experiments at higher space velocity no noticeable reduction in its effectiveness.

609852/1057

For comparison, the results of catalysts according to the invention Comparative experiments with known ones were carried out with other catalysts Dehydrogenation catalysts carried out. These experiments (Examples 11-14) were carried out in the same manner as the Example 1 to 10 carried out. Their results are summarized in Table II.

In Example 11, copper chromite tablets (0.5 cm) (Harshaw CU-0203) used as a catalyst. The values show the influence of the temperature change at a WHSV of 1. The conversion of sec-butanol in methyl ethyl ketone is low.

In Example 12, the same catalyst was used as in Example 11, but the dehydrogenation is 28 hours at a constant rate Temperature and a WHSV of 2. The values in Table II show the decrease in potency; of the catalyst over time, because the methyl ethyl ketone content is 81% ' back to 61%.

In Example 13, a copper metal catalyst (4-, 76 χ 1.68 mm) (Harshaw CU-2501) is used. The values in Table II show a very low conversion of sec-butanol into ethyl ethyl ketone at a WHSV of 2.

In Example 14 tablets with a diameter of 0.3 cm of copper oxide on diatomaceous earth (Girdler T-366) used as a catalyst. The temperature and the V / HSV were varied. With this one Example finds partial dehydration of alcohol

609852/1057

instead of. Since water is also formed, a two-phase product is obtained.

In example 15 tablets (0.4-7 x 0.3 cm) made of copper, Chromium and manganese (38/31/3) (Girdler T-97O) used as a catalyst. At a VJHSV of 2 or 4, the catalyst caused a slight conversion of sec-butanol into methyl ethyl ketone.

The catalysts produced by the process according to the invention result in a significant improvement over the known catalysts. The catalysts according to the invention show a high selectivity for the dehydrogenation versus the cleavage or dehydration of the alcohol and a good stability.

The catalysts of the invention normally do not require activation before use. The pretreatment of the catalyst with air and / or hydrogen at 54-0 ⁰ G - does not change the results of Example 1 significantly.

In Examples 1 to 15, sec-butanol was used. The use of the catalysts is not limited to lower alcohols and not limited to reactions in the gas phase. It is known that catalysts suitable for reactions in the gas phase of metals in elemental form are also suitable for reactions in the liquid phase. The invention Catalysts can be used for the dehydrogenation of alcohols at the required temperatures thermally

L J

609852/1 057

I Ji ti

are stable. Examples of alcohols that can be used are long-chain aliphatic cycloaliphatic benzyl and aralkyl alcohols,

^L 609852/1057

Claims (2)

Claims • Ί * Brass catalyst, characterized in that it consists of a brass powder or a powdery mixture of copper and zinc with a particle diameter of 0.0025 to 0.25 cm and a ratio of 95: 5 "to 50:50 by pressing with molding at pressures of 140 to 14,000 kg / cm and subsequent sintering of the molded parts at temperatures of 820 to 1440 ^° C. without reducing the porosity. 2. Catalyst according to claim 1, characterized in that it Copper and zinc in a proportion of 95: 5 to 80:20 2 contains and at pressures of 56ΟΟ to 8400 kg / cm and sintering temperatures of 1000 to 1325 ⁰ C has been produced. 35. A method for producing the catalyst according to claim 1, characterized in that a brass powder or a powdery mixture of copper and zinc with a particle diameter from 0.0025 to 0.25 cm and a ratio of copper to zinc of 95: 5 to 50:50 at pressures of 140 to 14,000 kg / cm pressed with molding and then the molded parts at temperatures of 820 to 1440 ° C without Reduction in porosity sinters. 609852/1057 ^Γ - 16 - and 2 4. Use of the catalyst according to claim 1 / for dehydrogenation of primary and secondary alcohols at temperatures of 2 94 to 540 ⁰ C and pressures of 0.07 to 7 kg / cm. 5. Embodiment according to claim 4, characterized in that the dehydrogenation is carried out at temperatures of 260-500 ⁰ C. 6. Embodiment according to claim 4 and 5, characterized in that that a secondary alcohol with an average molecular weight below 100 at an Eaumgeschwindig- 3 3 speed of 0.1 to 20 m of alcohol per m of the catalyst and 2 hours and dehydrated at pressures of 0.14 to 6 kg / cm. 7. Embodiment according to claim 4 to 6, characterized in that sec-butanol at a space velocity of 3 3 Dehydrogenated 1 to 6 m per m of the catalyst per hour. 8 .. embodiment according to claim 4, characterized in that the alcohol and the catalyst are in an inert solvent which is not very volatile at the temperature of the dehydrogenation brought into contact with one another and that the dehydrogenation is carried out at temperatures above the boiling point of the resulting Carbony! Compound, but below the boiling point of the alcohol used. J 6 0 9 8 5 ? / 1 Π 5 7 ¹ - 17 - 9. Embodiment according to claim 8, characterized in that that the dehydrogenation at temperatures from 94 to 318 ° C 2 and at pressures of 0.14 to 1 kg / cm. J 609852/1 057