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US3968172A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for the preparation of 2,4,6-trimethylphenol

Assignee: Teijin Ltd
•
Filing: 1973-10-02
•
Granted: 1976-07-06
•
Expires: 1993-10-02
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Abstract

Abstract A process for the preparation of 2,4,6-trimethylphenol by reacting a phenol of the formula (1) below, ##SPC1## In which R 1 and R 2 each stands for hydrogen atom or methyl group With methanol at vapor phase, in the presence of a magnesium oxide-containing catalyst, to methylate the former, the characteristic features residing in that the reaction is performed at the temperatures ranging from 400° to 500°C., and the gaseous mixture composed essentially of the phenol and methanol is contacted with the catalyst at a flow rate not higher than 0.4/hour (sum weight in grams of the phenol and methanol/catalyst's weight in grams/hour).

Inventors

  • 👤 Yataro Ichikawa
  • 👤 Yoshiyuki Yamanaka
  • 👤 Tatuyuki Naruchi
  • 👤 Osamu Kobayashi
  • 👤 Koichiro Sakota

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-07 18:18
CPC Classifications
C; C07; C07C; C07C37/00; C07C37/01; C07C37/055; B; B01; B01J; B01J21/00; B01J21/10; C07C37/11; C07C37/16

Claims Analysis

Total Claims: 21
Claim 1
Independent Claim 161 words
A process for the preparation of 2,4,6-trimethylphenol by reacting a phenolic compound of the formula: ##SPC9## in which R 1 and R 2 each stands for hydrogen atom or methyl group, with methanol at vapor phase to methylate the former, which comprises performing the reaction at a temperature in range of from 430° -475°C., the gaseous mixture being composed essentially of the phenolic compound and methanol being contacted at a flow rate not higher than 0.4/hour, calculated as the sum weight in grams of the phenol and methanol per catalyst's weight in grams/hour, with a catalyst of which at least 90% by weight consists of magnesium oxide, said catalyst containing (1) no acidic substance of acid strength of pKa 4.8 or below and no basic substance of base strength of pKa 18.4 or above, and having (2) the ratio of basicity (k) of 60 to 100% wherein: ##EQU4## and (3) a specific surface area of at least 15 m 2 /g.
Claim 2
Dependent Claim 161 words
A process for the preparation of 2,4,6-trimethylphenol by reacting a phenolic compound of the formula: ##SPC9## in which R 1 and R 2 each stands for hydrogen atom or methyl group, with methanol at vapor phase to methylate the former, which comprises performing the reaction at a temperature in range of from 430° -475°C., the gaseous mixture being composed essentially of the phenolic compound and methanol being contacted at a flow rate not higher than 0.4/hour, calculated as the sum weight in grams of the phenol and methanol per catalyst's weight in grams/hour, with a catalyst of which at least 90% by weight consists of magnesium oxide, said catalyst containing (1) no acidic substance of acid strength of pKa 4.8 or below and no basic substance of base strength of pKa 18.4 or above, and having (2) the ratio of basicity (k) of 60 to 100% wherein: ##EQU4## and (3) a specific surface area of at least 15 m 2 /g.
Claim 3
Dependent Claim 37 words
The process for the preparation of 2,4,6-trimethylphenol according to claim 1, in which the gaseous mixture composed essentially of the phenol and methanol is contacted with the catalyst at a flow rate ranging from 0.1 to 0.2/hour.
Claim 4
Dependent Claim 37 words
The process for the preparation of 2,4,6-trimethylphenol according to claim 1, in which the gaseous mixture composed essentially of the phenol and methanol is contacted with the catalyst at a flow rate ranging from 0.04 to 0.15/hour.
Claim 5
Dependent Claim 20 words
The process according to claim 1, in which the reaction is performed at the temperatures ranging from 420° to 490°C.
Claim 6
Dependent Claim 22 words
The process according to claim 1, in which the reaction is performed at the temperatures higher than 430°C. but lower than 475°C.
Claim 7
Dependent Claim 23 words
The process according to claim 1, in which the phenol and methanol are diluted with an inert gas and used for the reaction.
Claim 8
Dependent Claim 13 words
The process according to claim 6, in which the inert gas is steam.
Claim 9
Dependent Claim 36 words
The process according to claim 7, in which not more than 10 mols of water per mol of the phenol is used, and the phenol and methanol are diluted with the steam formed from said water.
Claim 10
Dependent Claim 49 words
The process according to claim 1, in which the methanol is used, based on the theoretical mol number of the methyl groups to be introduced into a mol of phenol to form 2,4,6-trimethylphenol, in the amount of 0.5 - 5 times the theoretical mol number per mol of phenol.
Claim 11
Dependent Claim 25 words
The process according to claim 1, in which the reaction is performed at the pressures ranging from 0.5 to 20 atmospheric pressures, as absolute pressure.
Claim 12
Dependent Claim 25 words
The process according to claim 1, in which the reaction is performed at the pressures ranging from 1 to 16 atmospheric pressures, as absolute pressure.
Claim 13
Dependent Claim 26 words
The process according to claim 1, in which the magnesium oxide has a pore radius (r) of 20 - 400 A is used as the catalyst.
Claim 14
Dependent Claim 26 words
The process according to claim 1, in which the magnesium oxide has a pore radius (r) of 30 - 150 A is used as the catalyst.
Claim 15
Dependent Claim 48 words
The process according to claim 1, in which at least one metallic compound selected from the group consisting of hydroxide, carbonate, phosphate, borate, silicate, aluminate of alkali metals and oxide, carbonate, phosphate, borate, of alkaline earth metals, is added to the magnesium oxide to serve as the catalyst.
Claim 16
Dependent Claim 32 words
The process according to claim 14, in which at most 10% by weight to the magnesium oxide of the metallic compound is added to the magnesium oxide to serve as the catalyst.
Claim 17
Dependent Claim 32 words
The process according to claim 14, in which up to 5% by weight to the magnesium oxide of the metallic compound is added to the magnesium oxide to serve as the catalyst.
Claim 18
Dependent Claim 25 words
The process according to claim 1, in which the phenolic compound is phenol containing no methyl substituent group, which is expressed by the formula, ##SPC10##
Claim 19
Dependent Claim 56 words
The process according to claim 1, in which the magnesium oxide-containing catalyst of which activity has been reduced is subjected to an oxidation treatment comprising contacting the catalyst with molecular oxygen or a molecular oxygen-containing gas at the temperatures ranging from 200° to 700°C., and the thus regenerated catalyst is used in the methylation of phenol.
Claim 20
Dependent Claim 78 words
The process according to claim 1, in which the magnesium oxide-containing catalyst of which activity has been reduced is subjected to an oxidation treatment comprising contacting the catalyst with molecular oxygen or a molecular oxygen-containing gas at temperatures ranging from 200° to 700°C., and then to a water treatment comprising contacting the catalyst with water or steam at the temperatures ranging from the normal to 650°C., and the thus regenerated catalyst is used in the methylation of phenol.
Claim 21
Dependent Claim 55 words
The process according to claim 1, in which the magnesium oxide-containing catalyst of which activity has been reduced is contacted with molecular oxygen or a molecular oxygen-containing gas at the temperatures ranging from 200° to 600°C., in the presence of water or steam, and the thus regenerated catalyst is used in the methylation of phenol.

References Cited (Backward Citations)

US3446856A Cited
US3764630A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-07-06 1980-01-05 1980-07-06 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-07-06 1984-01-05 1984-07-06 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-07-06 1988-01-05 1988-07-06 $7700.00 Window Closed / Lapsed

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