DE1643437B1 - Process for the production of hydroquinone - Google Patents

Description

1 2

The invention relates to a method of manufacture. in which acetylene, carbon monoxide, trimeric ruthenium

of hydroquinone by reacting acetylene with niumtetracarbonyl and water in the reaction

Carbon monoxide are temperature-soluble in a liquid from a mixture. Such solvents are

aromatic hydrocarbons, such as toluene, formed from water and an organic solvent; Ketones,

standing reaction medium at elevated temperature 5 such as acetone, methyl isobutyl ketone; Ether, like dioxane,

and increased pressure in the presence of a catalytic tetrahydrofuran, diisopropyl ether; Hydroxy ether,

effective amount of a ruthenium compound. such as 2-methoxyethanol, 2-ethoxyethanol, and esters,

It is known (cf. the German interpretation document such as ethyl acetate.

1135 486), hydroquinone from acetylene and carbon After the reaction has ended, the organic monoxide in the presence of a hydroxyl-containing solvent and any low-boiling point formed Compound in the presence of a halide, carbo-. Reaction products separated by distillation, nyls or chelate of ruthenium or rhodium The hydroquinone is preferably produced from the high. The yields of hydroquinone, based on the boiling residue, which is practically in water on acetylene, are insoluble when using ruthenium and which is the result of the catalyst Compounds below 20%, although the highest pressures contain 15 introduced ruthenium, by hot water. B. 700 to 1500 at, and high catalyst concentration separated off.

trations are applied. When using the In the recovery of ruthenium from the

very expensive rhodium chloride can result from the residue of the hot water extraction of the hydro-

hives can be increased, but it was not until the quinons that it was surprisingly found that the

Use of catalyst mixtures of Rhodi- 20 ruthenium catalyst still present in the residue

Umchlorid and triphenylphosphine 54% · When is catalytically active. Therefore, the backlog can be saved as

The turn of rhodium halides is their corrosive one, which can be used directly for further sales.

Adverse effect. Another disadvantage of this method is the same

driving lies in the long response time of 14 to the order of magnitude when using freshly

17 hours. 25-place trimeric ruthenium tetracarbonyl.

It is also known to produce hydroquinone from acetylene, the ruthe carbon monoxide and hydrogen present in the extraction residue at temperatures nium by treating the residue with salt from 100 to 300 ° C and pressures of 50 to 350 atm in acid or sodium hydroxide and sodium nitrate or the presence of an organic Solvent that does not contain sodium bromate and sulfuric acid or through a possible hydrogen atom, with trimeric burning of the residue in air as RuCl ₃ , RuO ₄ ", ruthenium tetracarbonyl as a catalyst, RuO ₄ or RuO _{2 can be} recovered. The so cf. the British patent 1,031,877. The ruthenium compounds that are maintained can then be converted back into trimeric ruthenium tetracarbonyl ^{30% by the process according to the German Auslegeschrift with a reaction time of 1 1 1} ₂ to 7 hours up to 1 216 276.

The invention is based on the object of hydro- The trimeric ruthenium tetracarbonyl can also

quinone in high yields after a technical one during the reaction from compounds which at

multiple processes in much shorter than under the reaction conditions in this carbonyl.

known processes to produce necessary times. be able to go, z. B. ruthenium acetylacetonate, basic

According to the invention this is achieved in that 40 cal ruthenium acetate or sodium hexachlororuthe-

the reaction can be formed using a Molver- nat.

ratio of water to acetylene from 0.5 to 5: 1, the catalyst concentration is not critical;

preferably 0.8 to 2.5: 1, in the presence of tri- expediently amounts of 0.2 to 1.0 g

merem ruthenium tetracarbonyl applied at temperatures of per liter of the reaction mixture.

200 to 280 ° C, preferably 220 to 26O ⁰ C, and 45 of the CO partial pressure does not affect the reaction.

Pressures from 50 to 450 at at the beginning of the reaction The proportion of the solvent is important for the

carries out and after the reaction has ended the hydrogenation of the reaction is not critical, but it has turned out to be

chinon wins in the usual way. proven to be beneficial at a molar ratio of

In the inventors' studies on the one-solvent to introduced acetylene of 2 to

To work with the presence of water at the hydroquinone 50 15: 1.

synthesis from acetylene and carbon monoxide as well as There are various ways to

Water as a hydrogen-forming substance in a quinone from the distillation residue of the reaction

to extract solvent and in the presence of trimeric ruthe mixture. Has been particularly beneficial

nium tetracarbonyl was surprisingly found, the extraction with hot water was found,
the fact that at temperatures of 200 to 280 ° C, before 55

preferably 220 to 260 ° C, and with a molar ratio example 1
Water to acetylene from 0.5 to 5: 1, preferably from

€, 8 to 2.5: 1, in the presence of trimeric ruthe- In a shaking autoclave made of acid-resistant

niumtetracarbonyl as a catalyst the yields of material with a capacity of 485 cm ³ was a

Hydroquinone increased to 60% and more and 60 glass tubes, the capillary tip outside of the

Reaction times can be achieved which far remains solvent, containing 0.15 g of trimer

are below those of the known methods. Ruthenium tetracarbonyl and a ball of acid-free

The implementation according to the invention also works with permanent steel. The autoclave was opened Temperatures below 200 and above 280 ° C, but cools. After removing the air, 151 g of tetra ran the reaction at temperatures below 200 ° C 65 hydrofuran, 8 g of water and 0.249 mol of acetylene is pretty slowly and yields at temperatures brought over. Subsequently, carbon monoxide was up 280 ° C a decrease in yield. pushed in to a pressure of 122 at and the

Such substances are used as solvents, the autoclave is heated to 250 ° C with shaking. Of the

Pressure reached a value of 310 at. The autoclave was now turned over, thereby removing the catalyst The glass tube containing it broke.

The reaction started immediately, which was evident from the drop in pressure. Than after 35 minutes a constant pressure had been set, the autoclave was quickly cooled and let down. The escaping Gases were analyzed; no more acetylene could be found.

The liquid reaction mixture was removed from the autoclave and distilled at normal pressure. Of the The distillation residue of 15.7 g was extracted with hot water in an extractor for 15 hours. Thereafter, the water was removed under reduced pressure (20 torr) and the obtained crude Hydroquinone sublimed at a pressure of 1.5 to 2 torr. There were 8.2 g of hydroquinone, accordingly a yield of 59.8% (melting point 1 '/ 0 to 172 ° C).

Examples 2 to 7

The data for the further Examples 2 to 7 are listed in Table 1 below.

The execution of the experiments corresponds to that of example 1.

Tabel

[Ru (CO) ₁ I ₃ solvent O ₂ H ₂ O ₂ H ₂ H ₂ O Moles of H ₂ O pressure temperature Reak Yield to
Hydroquinone, turned vice MoIC ₂ H ₂ geixtcbbC-u Dei
Reaction ions related to G Type g puts puts G temperature ° C Time implemented
O ₂ H ₂ 0.15 Tetrahydro Mole Mole 8.0 1.79 at 250 to 255 Min. % 2 furan 151.0 0.249 0.249 310 35 59.8 0.08 Tetrahydro 8.1 2.09 260 to 270 3 furan 266.0 0.216 0.216 400 30th 52.0 0.2 Methyl isobu- 9.0 1.96 250 to 260 4th tylketone 240.0 0.257 0.255 390 20th 56.5 0.15 Diisopropyl 8.0 2.06 250 to 260 5 ether 218.0 0.216 0.216 410 35 48.2 0.15 2-ethoxyether 8.0 2.10 260 6th nol 279.0 0.212 0.212 365 19th 55.0 0.15 Methyl isobu- 8.0 2.04 280 to 290 7th tylketone 240.0 0.218 0.218 392 10 37.1

Example 8

In a stainless steel shaking autoclave with a capacity of 485 cm ³ , 0.3 g of [Ru (CO) I ₃ as in Example 1 was placed in a glass vessel.

The autoclave was cooled and after removing the air, 222 g of tetrahydrofuran, 10.4 g of water and 0.301 mol of acetylene were introduced. Carbon monoxide was then pressed in up to a pressure of 150 atm. The autoclave was then heated to 220 ° C; the pressure reached a value of 270 at. The autoclave was turned upside down, whereby the glass tube containing the catalyst broke. The reaction started immediately, and after 55 minutes, when the drop in pressure had stopped, the autoclave was quickly cooled with cold water. The escaping gases no longer contained any acetylene.
After the pressure-relieved autoclave was opened, acetylene, carbon monoxide and water were again introduced without working up the reaction mixture. This operation was repeated six times in all. The reaction conditions for the individual operations are given in Table 2 below.

Tabel

approach C ₂ H ₂
used C ₂ H ₂
recovered water CO
pressure
at 25 ° C Total pressure
at reaction
temperature Reaction
Time temperature Mole Mole G at at Minutes ° C 2 0.292 0 6th 130 268 55 220 3 0.298 0 6.2 180 309 63 220 4th 0.320 0 7.2 170 329 62 220 5 0.285 0 7.0 153 280 51 220 6th 0.313 0 7.0 180 362 60 220 7th 0.313 0 5.0 165 438 63 215

The reaction mixture was then removed from the depressurized autoclave and under normal pressure the tetrahydrofuran is distilled off. The residue of 115.7 g was then washed with water Extracted in an extractor for 24 hours.

The water was distilled off at 20 torr and that

raw hydroquinone sublimed at 1.5 to 2 torr. There were 69.1 g of hydroquinone (melting point 170 to 172 ° C) obtained, which corresponds to a yield of 59.4%> based on acetylene.

Example 9

Part of the water-insoluble residue from Example 8, which was obtained during the water extraction (15.3 g) and containing the catalysts was dissolved in 215 g of tetrahydrofuran and returned to the autoclave. After evacuation to remove air, the cooled autoclave was charged with 12 g of water and 0.352 moles of acetylene were introduced. Carbon monoxide was then injected to a pressure of 154 atm. The mixture was heated to 230 ° C. with shaking; the pressure reached 298 at. After 61 minutes it was the reaction ended; the autoclave was quickly cooled and depressurized. In the escaping gases no more acetylene was detected.

In the autoclave containing the reaction mixture, a further 8 g of water and 0.41 mol of acetylene and then CO introduced up to a pressure of 177 at. The reaction temperature was 240 ° C., the reaction pressure was 426 atm and the reaction time was 33 minutes.

As previously described in Example 8, the hydroquinone was obtained. This resulted in 27.3 g, this corresponds to a yield of 65.2%.

Claims (2)

Patent claims: 1. Process for the production of hydroquinone by reacting acetylene with carbon monoxide in a liquid consisting of a mixture of water and an organic solvent Reaction medium at elevated temperature and pressure in the presence of a catalytically effective amount of a ruthenium compound, characterized in that the reaction is carried out using a molar ratio from water to acetylene from 0.5 to 5: 1, preferably 0.8 to 2.5: 1, in the presence of trimeric ruthenium tetracarbonyl at temperatures from 200 to 280 ° C, preferably 220 to 260 ° C, and pressures of 50 to 450 atm at the beginning of the reaction and after the reaction has ended Hydroquinone wins in the usual way. 2. The method according to claim 1, characterized in that the reaction is carried out in the presence of Carries out 0.2 to 1.0 g of the catalyst per liter of the reaction mixture.