DE1222070B - Process for the production of phenol from benzene - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. Cl .:

C07c

German class: 12 q- 14/02

Number; _;
File number:
Registration date:
Display day:

1222070
D36099IVb / 12q May 16, 1961 August 4, 1966

There are already several methods of manufacture of phenol; known from benzene, in which benzene is subjected to direct oxidation. So can For example, in the gas state, a reaction between benzene and oxygen at high temperature or at 5 high temperature and · high: pressure carried out will. Furthermore, the conversion of benzene to phenol is in the liquid state in the presence of hydrofluoric acid known as a catalyst. However, these known methods cannot be used on an industrial scale be performed. It is also known to produce phenol by direct oxidation of benzene in the presence of copper salt and water. In this reaction, the copper takes directly as one to be reduced Reactants part. Copper must therefore be present in large quantities, and one is produced large amount of precipitation of elemental copper, the further treatment of which is very laborious.

It is also known that you can use benzene in aqueous. Solution with oxygen and under the action of ao an ionizing radiation can oxidize, whereby the following reactions take place:

Process for the production of phenol from benzene

Applicant:

Nihon Genshiryqku Kenkyujo, Showa Denko Kabushiki Kaisha, Tokyo

Representative:

Dipl.-Phys. G. Liedl, patent attorney, Munich 22, Steinsdorfstr. 22nd

Named as inventor:

Akibumi Danno, '

Hiröshi Hotta, Teppocho Mito City; Akira Terakawa, Kitaku, Tokyo (Japan)

Claimed priority:

Japan May 17, 1960 (24134)

H ₂ O -> H, OH, H ₂ , H ₂ O ₂ PhH + OH -> Ph + H ₂ O Ph + O ₂ + H ₂ O - * PhOH + HO.

2HO ₂ - ^ H ₂ O ₂ + O ₂ Ph + OH - ^ PhOH Ph + Ph -> Ph ₂

In these formulas, Ph means the phenyl radical.

However, in the above reaction scheme, the G value of phenol 'is at most 2.9, * where below G value is understood as the number of molecules that are produced by absorbing a radiation energy of 100 eV is generated:

G =

Number of molecules generated absorbed radiation energy in eV

100.

It is also known ^ hating the yield of phenol can be increased somewhat by the presence of Fe ions. Nevertheless, the yield remains extreme low.

It is also known that the yield of phenol by irradiating an aqueous benzene solution can be increased at high temperatures and under strong oxygen or air pressure. However Even under these conditions, the highest G value of phenol is only around 50.

The process of the invention for the preparation of phenol by oxidizing an aqueous benzene solution with oxygen or air in the presence of sulfates or chlorides of copper or iron as a catalyst optionally under irradiation with ionizing radiation is characterized by that one in a reaction vessel with flow or stirring a neutral or acidic with benzene saturated aqueous solution in the presence of an amount of catalyst of about 0.01 mol per 1 at a

■ ·· Temperature between about 150 and 230 ° C under a pressure of 30 to 80, especially 30 atmospheres. Phenol with a G value greater than 500 can be recovered by the process of the invention.

The irradiation can be done with x-rays, y-rays, Electron rays, /? Rays, proton rays, «rays, or neutron rays will.

The figure shows schematically an apparatus in which the method of the invention is carried out. Numeral 1 denotes a reaction vessel; 2 is a pipe for introducing oxygen or air into the reaction vessel 1; 3 is a pipeline for the introduction of a benzene-saturated, aqueous Solution in the reaction vessel, this solution containing the catalyst; 4 is a line to withdraw the reaction product from the reaction vessel 1; 5 denotes an electric heater, the heating coils of which the reaction vessel 1

· ■■■ '· - ■' ■ "'' ■ · ^: -" ^{: Ώϊ} 609 608/395

surround and which serve to heat the vessel 1; 6 denotes a radiation source, and 7 is a screening wall.

The method of the invention can also be carried out without the use of radiation, the temperature preferably above 170 ° C. and the pressure about 30 to 80, preferably 45 to 70 at ,amounts to.

The following examples serve to illustrate the process of the invention. . to

example 1

1 part by volume of benzene and 15 parts by volume of water are mixed together. The benzene-saturated aqueous solution is then placed under an oxygen pressure heated from 30 at for a time of 30 minutes to a temperature of 200 ° C, with none Implementation and no formation of phenol occurs. If, however, the benzene-saturated, aqueous solution 0.01 mol per liter of copper sulphate are added and the solution is treated under the above conditions; phenol is obtained with a benzene-based yield of 2.5% (percent by weight).

Example2

A benzene-saturated aqueous solution, which consists of 15 ecm of an aqueous copper sulfate solution of 0.01 mol per liter and 1 ecm of benzene is made with Co-60 y rays using various Radiation doses and irradiated at different temperatures for 30 minutes each. The oxygen pressure is 30 at.

The following results are achieved:

Tempe
rature Irradiation
Roentgen Phenol yield difference ⁰ C per hour Moles per liter in G value 150 - *) 0.05 122 150 3,400 0.26 175 - *) 0.33 492 175 3,400 1.18 180 - *) 0.72 1002 180 3,400 2.45 200 - *) 15.84 752 200 3,300 17.10 210 - *) 16.15 1462 210 3,300 18.60 230 - *) 19.61 1254 230 3,300 21.71

*) No irradiation took place in these experiments.

Example 3

The benzene and oxygen-saturated aqueous solution (30 ecm), to which various salts, as they are in the The table below will be added using Co-60 y rays with a power of 3 · 10 * X-rays per hour for one hour at 150 ° C and under an oxygen pressure of 30 at irradiated. Under the same conditions, but without irradiation, one also obtains phenol, which is also listed in the same table.

Concentration. solvent Phenol yield not irradiated catalyst in ivioi per J_.iter mmol per hour 0.01 H ₂ O irradiated (<? - value) 1 . CuSO ₄ 0.01 H ₂ O 500 16 CuCl ₂ 0.01 0.01 nH ₂ SO ₄ 900 6th FeSO ₄ 0.01 0.01 nH ₂ SO ₄ 600 5 Fe ₂ (SO ₄ ) ₃ 0.01 H ₂ O . 400 22nd FeCl ₂ 0.01 H ₂ O 2000 18th FeCl ₃ 0.01 0.01 n-HCl 1500 20th CuCl ₂ 0.01 0.01 n-HCl 4000 35 FeCl ₂ - H ₂ O 5000 - > 10

Claims (1)

Claim: Process for the preparation of phenol by oxidizing an aqueous benzene solution with oxygen or air in the presence of sulfates or chlorides of copper or iron as a catalyst, optionally with irradiation with ionizing radiation, characterized in that a neutral or acid, saturated aqueous solution with benzene in the presence of a catalyst amount of from about 0.01 mole per liter at a temperature between about 150 and 23O ⁰ C and under a pressure of about 30 to 80 at, particularly 30 at oxidized. Considered publications: U.S. Patent No. 2,760,991; Discussions of the Faraday Society, No. 14, 1953, pp. 160 "to 169; Journal of Chemical Physics, Vol. 23/1, 1955, p. 604; Vol. 20 / H, 1952, pp. 1817 to 1818. 1 sheet of drawings 609 608/395 7.66 © Bundesdruckerei Berlin