Method for producing phenylalkyl ether from phenol / o-cresol fraction

Abstract

The invention discloses a method for producing phenylalkyl ether from phenol / o-cresol fractions, which comprises the following steps: rectifying phenol-containing raw materials to obtain a mixture containing phenol and o-cresol, the phenol-containing raw materials comprising crude phenol containing phenol and o-cresol, mixed phenol, o-cresol fractions, m-p fractions and phenol-containing coal tar; alkylating a mixture containing phenol and o-cresol, and washing to obtain a material layer; and rectifying the material layer to obtain a product comprising the phenylalkyl ether and the o-methyl phenylalkyl ether. The mixture containing phenol and o-cresol is used as a raw material, phenol and o-cresol are converted into phenylalkyl ether and o-methyl phenylalkyl ether through reaction with an alkylating agent and the like, the boiling point difference of the two materials after etherification is increased, the boiling point is reduced, and the melting point is reduced; therefore, the difficulty of rectifying and separating the mixture of the phenylalkyl ether and the o-methyl phenylalkyl ether is obviously reduced, the rectifying yield and the rectifying cost are greatly reduced, and the method is more economical.

Description

Technical Field

[0001] The invention relates to the technical field of coal coking separation and organic synthesis, in particular to a method for producing phenyl alkyl ether from phenol / o-cresol fractions. Background Art

[0002] Phenolic coal tar, phenolic phenol oil, etc. contain phenol, o-cresol, m-cresol, xylenol, tri-cresol and other substances. Alkaline dissolution, acid precipitation and solvent extraction methods are generally used to produce crude phenol, and then the crude phenol is distilled to obtain mixed phenol fractions, cresol fractions, xylenol fractions, etc., and then the mixed phenol is refined (distilled) to obtain phenol, refined o-cresol and other products. Phenol or o-cresol is then reacted with an etherification agent to obtain phenyl alkyl ethers and methyl phenyl alkyl ethers. The process is relatively long and the production cost is high.

[0003] Among them, the mixture containing phenol and o-cresol obtained in the refining of crude phenol contains more phenol as mixed phenol and more o-cresol as o-cresol fraction. The mixed phenol can be distilled to obtain phenol products, and the o-cresol fraction can be distilled to obtain refined o-cresol. Therefore, the manufacturing cost of phenol and refined o-cresol is higher than that of mixed phenol and o-cresol fraction, and the price is also higher than them. The boiling point difference between o-cresol and phenol is 9°C, while the boiling point difference between o-methyl anisole and anisole is 17°C. Therefore, it is easier to separate phenol and o-cresol in mixed phenol into anisole and o-methyl anisole, and the separation cost will be greatly reduced. Summary of the invention

[0004] The present invention aims to solve one of the technical problems in the related art at least to a certain extent.

[0005] To this end, an embodiment of the present invention provides a method for producing phenyl alkyl ether from a phenol / o-cresol fraction. The present invention uses a cheap phenol / o-cresol mixture to replace pure phenol and pure o-cresol to synthesize chemical raw materials phenyl alkyl ether and o-methyl phenyl alkyl ether, which greatly reduces the production cost of phenyl alkyl ether and o-methyl phenyl alkyl ether, increases market competitiveness, and solves the separation and utilization problems of phenol / o-cresol mixture or phenol / o-cresol phenol oil fraction. The method of the present invention has low requirements for raw materials, good operability, strong practicality, and significant economic benefits.

[0006] The present invention provides a method for producing phenyl alkyl ether from a phenol / o-cresol fraction, comprising the following steps:

[0007] (a) distillation and purification: distilling a phenol-containing raw material to obtain a mixture containing phenol and o-cresol, wherein the phenol-containing raw material includes crude phenol, mixed phenol, o-cresol fraction, m-cresol fraction, and phenol-containing coal tar;

[0008] (b) etherification: alkylating the mixture containing phenol and o-cresol, and washing to obtain a material layer;

[0009] (c) Separation: distilling the material layer to obtain products including phenyl alkyl ether and o-methylphenyl alkyl ether.

[0010] In some embodiments, when the phenol-containing raw material is phenol-containing coal tar, the mixture containing phenol and o-cresol is a phenol / o-cresol phenol oil fraction, and a non-phenol component removal process is also included before step (b).

[0011] In some embodiments, the non-phenol component removal process is to stir the phenol / o-cresol phenol oil and the alkaline aqueous solution at 30-80° C. for 1-2 hours, stand for stratification, remove the upper oil layer without phenolic compounds, and retain the lower water layer. The purpose of this process is to remove the oil that is not a phenolic compound.

[0012] In some embodiments, the aqueous alkaline solution is one or more of a sodium methoxide solution, a sodium ethoxide solution, a sodium hydroxide solution, or a potassium hydroxide solution.

[0013] In some embodiments, the step (b) is to drop an alkylating agent into the water layer, keep the temperature for 2 to 20 hours, and after the raw material conversion rate reaches more than 95%, stand to separate the water layer, and wash to obtain a material layer.

[0014] In some embodiments, when the phenol-containing raw material is crude phenol, mixed phenol, o-cresol fraction, or m-cresol fraction containing phenol and o-cresol, the mixture containing phenol and o-cresol is a phenol / o-cresol fraction with a distillation range of ≤192°C.

[0015] In some embodiments, the step (b) is to drop an alkylating agent into the phenol / o-cresol fraction under catalyst conditions, keep warm for 2 to 20 hours, and after the raw material conversion rate reaches more than 95%, stand to separate the water layer and wash to obtain a material layer.

[0016] In some embodiments, the catalyst is one or more of aluminum oxide, magnesium oxide, nickel oxide, or one or more of sodium methoxide solution, sodium ethoxide solution, sodium hydroxide solution, and potassium hydroxide solution.

[0017] In some embodiments, the alkylating agent is one or more of iodoalkanes, chloroalkanes, brominatedalkanes, di-fatty sulfates, di-fatty carbonates, and fatty alcohols.

[0018] In some embodiments, the process of washing to obtain the material layer is to sequentially wash the material layer with 10% sulfuric acid and deionized water.

[0019] Compared with the prior art, the beneficial effects of the present invention are:

[0020] The invention uses a mixture containing phenol and o-cresol as a raw material, and converts the phenol and o-cresol therein into phenyl alkyl ether and o-methylphenyl alkyl ether by reacting with an alkylating agent or the like. After etherification, the difference in boiling points of the two materials is widened, the boiling point is reduced, and the melting point is reduced. Therefore, the difficulty of distilling and separating the mixture of phenyl alkyl ether and o-methylphenyl alkyl ether is significantly reduced, and the distillation yield and distillation cost are greatly reduced, so that the invention is more economical.

[0021] In the present invention, a mixture containing phenol and o-cresol reacts with an alkylating agent under low temperature conditions under the action of a catalyst, and only etherification products are produced without generating an alkylation reaction on the benzene ring. Therefore, the product is a mixture of phenyl alkyl ether and o-methylphenyl alkyl ether. High-purity phenyl alkyl ether and o-methylphenyl alkyl ether are obtained by distillation separation, thereby avoiding the problems of catalyst poisoning and deactivation occurring in the high-temperature etherification of phenol products in a fixed bed, and the quality requirements for the phenol / o-cresol mixture are not high.

[0022] The raw materials of the invention are widely available, the raw materials are easy to prepare, the selected reaction conditions are mild, the side reactions are very few, the etherification selectivity is good, and the phenyl alkyl ether, o-methylphenyl alkyl ether, phenol and o-cresol can be separated by distillation after the reaction to produce phenyl alkyl ether and o-methylphenyl alkyl ether. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0024] Figure 1 The present invention is a process flow chart for producing phenyl alkyl ether from phenol / o-cresol fraction. DETAILED DESCRIPTION

[0025] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0026] The following describes a method for producing phenyl alkyl ether from a phenol / o-cresol fraction according to an embodiment of the present invention with reference to the accompanying drawings.

[0027] like Figure 1 As shown, the method for producing phenyl alkyl ether from phenol / o-cresol fraction of the present invention comprises the following steps:

[0028] (a) distillation and purification: distilling a phenol-containing raw material to obtain a mixture containing phenol and o-cresol, the phenol-containing raw material including crude phenol, mixed phenol, o-cresol fraction, m-cresol fraction, and phenol-containing coal tar;

[0029] (b) etherification: alkylating a mixture containing phenol and o-cresol, and washing to obtain a material layer;

[0030] (c) Separation: distilling the material layer to obtain products including phenyl alkyl ether and o-methylphenyl alkyl ether.

[0031] When the phenol-containing raw material is phenol-containing coal tar, the mixture containing phenol and o-cresol is a phenol / o-cresol phenol oil fraction, and a non-phenol component removal process is also included before step (b). The phenol-containing coal tar comes from coal pyrolysis and coal gasification processes. The phenol / o-cresol phenol oil fraction is a phenol oil fraction containing phenol and o-cresol.

[0032] Specifically, in step (a), phenol-containing coal tar is added to a distillation tower or a tubular furnace, and distillation is performed to obtain a fraction of less than 170° C., a phenol oil fraction of 170-230° C., a tricresol fraction of 230-240° C., and a fraction of 240-300° C. The residue is medium-temperature coal tar, wherein the phenol oil fraction of 170-230° C. contains a phenol / o-cresol phenol oil fraction of 170-192° C., and the phenol / o-cresol phenol oil fraction of 170-192° C. is a fraction containing phenol and o-cresol, with less m-p-cresol, and the residue is used for hydrogenation to produce oil products.

[0033] The non-phenol component removal process is to put phenol / o-cresol phenol oil distillate and alkaline aqueous solution into the reactor, heat it to 30-80°C, stir it for 1-2 hours, and let it stand to separate the layers. The upper layer is an oil layer that does not contain phenolic compounds. The upper oil layer that does not contain phenolic compounds is removed, and the lower water layer is retained.

[0034] The composition of phenolic substances after deducting the oil containing no phenolic compounds is 1% to 98% of phenol, 1% to 98% of o-cresol, 0 to 5% of m-cresol, and 0 to 20% of 2,6-dimethylphenol. Preferably, the composition of phenolic substances after deducting the oil containing no phenolic compounds is 25% to 95% of phenol, 5% to 75% of o-cresol, 0 to 1% of m-cresol, and 0 to 10% of 2,6-dimethylphenol.

[0035] The alkaline aqueous solution is one or more of sodium methoxide solution, sodium ethoxide solution, sodium hydroxide solution or potassium hydroxide solution. It is understood that the amount of the alkaline aqueous solution is specifically set according to the amount of phenol / o-cresol phenol oil fraction. The alkaline aqueous solution is used to remove phenol oil and is also used as a catalyst in subsequent processes.

[0036] Step (b) is to drop an alkylating agent into the water layer obtained in the above non-phenol component removal process in a reactor, keep it warm for 2 to 20 hours under a slightly boiling condition, and after qualified analysis, let the water layer stand and separate the water layers, and add 10% sulfuric acid and deionized water to the material layer in turn to wash the material layer.

[0037] The alkylating agent is one or more of iodoalkane, chloroalkane, bromoalkane, difatty sulfate, difatty carbonate, and fatty alcohol, and the molar ratio of phenolic substances to alkylating agents in the water layer is 1:0.5-5, preferably 1:1-3. The micro-boiling condition refers to the presence of a small amount of small bubbles in the mixed solution, but not reaching the boiling state. The qualified analysis means that the conversion rate of the main raw materials reaches more than 95%. The amount of sulfuric acid used for washing is 5% to 20% of the amount of the material. Washing with sulfuric acid can remove impurities, and the amount of deionized water is 10% of the amount of the material.

[0038] Step (c) is to obtain products including phenyl alkyl ether and o-methylphenyl alkyl ether by distilling the material layer. The phenyl alkyl ether includes anisole, phenethyl ether, phenylpropyl ether and phenbutyl ether, and the o-methylphenyl alkyl ether includes o-methylanisole, o-methylphenethyl ether, o-methylphenpropyl ether and o-methylphenbutyl ether.

[0039] The phenol-containing coal tar fractionation or rectification at medium and low temperature can collect the phenol-containing phenol oil fraction containing phenol and o-cresol. For the convenience of separation, the phenol / o-cresol phenol oil fraction with a distillation range of <192°C is selected as one of the raw materials of the present invention. The p-cresol content in this fraction is low, and the main components are phenol, o-cresol, and some 2,6-dimethylphenol. Sodium phenol, sodium o-methylphenol, and sodium 2,6-dimethylphenol are obtained by alkali washing and are dissolved in water. The oil layer without phenolic compounds and the sodium phenol salt can be separated by layering, and the separation is relatively easy. The sodium phenol salt is then reacted with an etherification agent to obtain the corresponding etherified product, which is insoluble in water, and the separation of the material and the water layer is achieved again. The material can be washed with chemicals and water to purify the material. The material layer is distilled to obtain high-quality phenyl ether, o-methyl phenyl ether and other products with high value.

[0040] The present invention does not adopt phenol / o-cresol phenol oil to directly etherify under organic alkaline catalysis, but adopts alkali solution extraction to obtain the oil layer without phenolic compounds and sodium phenolate, and the sodium phenolate is etherified and synthesized, so that the boiling point of phenolic etherification products can be avoided to fall in the oil without phenolic compounds, causing the etherification products and the oil layer without phenolic compounds to be difficult to separate. Taking the methyl etherification reaction as an example: the boiling point of o-methyl anisole is 171°C and the boiling point of 2,6-dimethyl anisole is 182°C. If the phenol-containing phenol oil is directly etherified, it will be impossible to separate 2,6-dimethyl anisole from the phenol oil by distillation (the boiling point of the phenol oil is 170-192°C), and the desired oil without phenolic compounds and 2,6-dimethyl anisole cannot be obtained, and it is not easy to obtain high-purity o-methyl anisole.

[0041] When the phenol-containing raw material is crude phenol, mixed phenol, ortho-cresol fraction, or meta-cresol fraction containing phenol and ortho-cresol, the mixture containing phenol and ortho-cresol is the phenol / ortho-cresol fraction. Among them, the crude phenol is the crude phenol obtained by dephenolization of coal gasification wastewater, and the mixed phenol, ortho-cresol fraction, ortho-cresol fraction and meta-cresol fraction are derived from the distillation process of the crude phenol. The phenol / ortho-cresol fraction is a fraction containing phenol and ortho-cresol.

[0042] Specifically, in step (a), the phenol-containing raw material is distilled to obtain a phenol / o-cresol fraction with a distillation range of ≤192°C. The contents of the components in the phenol / o-cresol fraction are 1% to 98% of phenol, 1% to 98% of o-cresol, 0% to 5% of m-cresol, and 0% to 20% of 2,6-dimethylphenol. Preferably, the contents of the components in the phenol / o-cresol fraction are 25% to 95% of phenol, 5% to 75% of o-cresol, 0% to 1% of m-cresol, and 0% to 10% of 2,6-dimethylphenol.

[0043] Step (b) is to put phenol / o-cresol fraction and catalyst into a reactor, add alkylating agent dropwise under catalyst condition, keep warm for 2 to 20 hours under slightly boiling condition, stand to separate water layer after qualified analysis, and wash to obtain material layer.

[0044] The catalyst is one or more of aluminum oxide, magnesium oxide, nickel oxide, or one or more of sodium methoxide solution, sodium ethoxide solution, sodium hydroxide solution, and potassium hydroxide solution. The amount of the catalyst is not greater than the amount of the phenol / o-cresol fraction. In practical applications, the amount of the catalyst is specifically set according to the amount of the phenol / o-cresol fraction. The alkylating agent is one or more of iodoalkane, chloroalkane, bromoalkane, difatty sulfate, difatty carbonate, and fatty alcohol. The molar ratio of phenolic substances to alkylating agents in the water layer is 1:0.5-5, preferably 1:1-3. The micro-boiling condition refers to a state in which the mixed solution contains a small amount of small bubbles but does not reach boiling. The qualified analysis means that the conversion rate of the main raw material reaches more than 95%. The amount of sulfuric acid used for washing is 5% to 20% of the amount of the material. Washing with sulfuric acid can remove impurities. The amount of deionized water is 10% of the amount of the material.

[0045] Step (c) is to obtain products including phenyl alkyl ether and o-methylphenyl alkyl ether by distilling the material layer. The phenyl alkyl ether includes anisole, phenethyl ether, phenylpropyl ether and phenbutyl ether, and the o-methylphenyl alkyl ether includes o-methylanisole, o-methylphenethyl ether, o-methylphenpropyl ether and o-methylphenbutyl ether.

[0046] Example 1

[0047] Crude phenol is distilled to obtain phenol / o-cresol fraction, m-cresol, mixed xylenols, mixed trimethylols, mixed diphenol fractions and the like.

[0048] Add 5410 parts of phenol / o-cresol fraction (phenol 68.9%, o-cresol 30.9%, other 0.2%) obtained by crude phenol rectification in the previous step, 13500 parts of 20% sodium hydroxide aqueous solution, start stirring, start dripping 3000 parts of dimethyl carbonate, control the dripping temperature to 55±5°C, the dripping time is about 4 hours, keep the reaction at a low temperature for 10 hours after the dripping, take samples for analysis, phenol 0.36%, phenol conversion rate reaches 99.5%, cool to 80°C and stand for stratification, separate the lower water layer, and retain the material layer. Add 100 parts of toluene to the water layer for extraction once, send the separated water layer to the wastewater station, mix the toluene layer with the material layer, add 150 parts of water, stir and drip 10 parts of sulfuric acid for 1 hour to remove impurities, separate, wash the material layer with 150 parts of water, separate the water to obtain the material layer. The material layer was sampled and analyzed for sulfur and nitrogen content using gas chromatography, trace sulfur and nitrogen analyzer and other analytical instruments. The sulfur and nitrogen content was 2.4 ppm.

[0049] The above material layer is added into a distillation kettle, and 98.3 parts of toluene are recovered by atmospheric distillation, and then changed to vacuum distillation (-0.085MPa), with a reflux ratio of 10:1, and full reflux for 1.5 hours for every 6 hours of distillation. Under chromatographic analysis, 4163.2 parts of 99.8% anisole (99.80% anisole, 0.19% o-methyl anisole, and 0.01% of others), 69.4 parts of intermediate fractions (58.64% anisole, 41.21% o-methyl anisole, and 0.15% of others), 1701.7 parts of 99.9% o-methyl anisole (0.07% anisole, 99.91% o-methyl anisole, and 0.02% of others) and 162.9 parts of distillation kettle residue (including 132.1 parts of o-methyl anisole) are accurately collected.

[0050] The middle fraction is incorporated into the distillation product of the next batch of etherified products; the still residues from multiple batches are combined and then distilled into o-methylanisole.

[0051] Example 2

[0052] Add 2700 parts of phenol / o-cresol fraction (which substance is obtained by distillation) obtained by crude phenol rectification in Example 1 (phenol 26.9%, o-cresol 72.8%, other 0.3%), 4500 parts of 30% sodium hydroxide aqueous solution, start stirring, start dripping 2150 parts of dimethyl sulfate, control the dripping temperature to 55±5°C, the dripping time is about 4 hours, after dripping, keep the reaction for 6 hours under the condition of slight boiling, take samples for analysis, o-cresol 0.17%, the conversion rate of o-cresol reaches 99.8%, cool to 80°C and stand for stratification, separate the lower water layer, send the water layer to the waste water station, and retain the material layer. Add 100 parts of toluene to the water layer for extraction once, send the separated water layer to the waste water station, mix the toluene layer with the material layer, add 50 parts of water to the material layer, stir and drip 5 parts of sulfuric acid for 1 hour to remove impurities, separate, wash the material layer with 50 parts of water, separate the water, obtain the material layer and carry out the following treatment.

[0053] The above material layer was added to the distillation kettle, and vacuum distillation was performed (-0.085MPa), with a reflux ratio of 10:1, and full reflux for 1.5 hours for every 8 hours of distillation. The first portion (16.5 parts of anisole), 791.9 parts of anisole (99.78% of anisole, 0.18% of o-methyl anisole, and 0.04% of others), 47.9 parts of the middle fraction (36.74% of anisole, 62.84% of o-methyl anisole, and 0.42% of others), 2090.5 parts of o-methyl anisole (0.09% of anisole, 99.88% of o-methyl anisole, and 0.03% of others) were collected, and 84.1 parts of the distillation kettle residue (including 78.6 parts of o-methyl anisole) were collected.

[0054] The middle fraction is incorporated into the distillation product of the next batch of etherified products; the still residues from multiple batches are combined and then distilled into o-methylanisole.

[0055] Example 3

[0056] Add 5410 parts of phenol / o-cresol fraction (which substance is obtained by distillation) obtained by crude phenol rectification in Example 1 (phenol 68.9%, o-cresol 30.9%, other 0.2%), 13500 parts of 20% sodium hydroxide aqueous solution, start stirring, start dripping 3670 parts of diethyl carbonate, control the dripping temperature to 75±5℃, dripping time is about 6 hours, dripping is completed, keep the reaction under slight boiling conditions for 12 hours, sample analysis, phenol 0.41%, phenol conversion rate reaches 99.4%. Cool to 80℃ and let stand for stratification, separate the lower water layer, and retain the material layer. Add 100 parts of toluene to the water layer for extraction once, send the separated water layer to the wastewater station, mix the toluene layer with the material layer, add 100 parts of water to the material layer, stir and drip 10 parts of sulfuric acid for 1 hour to remove impurities, separate, wash the material layer with 100 parts of water, separate the water, obtain the material layer and carry out the following treatment.

[0057] The above material layer was added into a distillation kettle, and distilled under reduced pressure (-0.088MPa), with a reflux ratio of 10:1, and full reflux for 1 hour for every 4 hours of distillation. Under chromatographic analysis, 4613.4 parts of 99.7% phenethyl ether (99.7% phenethyl ether, 0.26% o-methyl phenethyl ether, and 0.04% of others), 172.6 parts of intermediate distillates (58.82% phenethyl ether, 41.08% o-methyl phenethyl ether, and 0.10% of others), 1858.9 parts of 99.9% o-methyl phenethyl ether (0.09% phenethyl ether, 99.86% o-methyl phenethyl ether, and 0.05% of others) and 181.6 parts of distillation kettle residue were accurately collected. (Among them, 137.1 parts of o-methyl phenethyl ether)

[0058] The middle fraction is incorporated into the distillation product of the next batch of etherified products; the still residues from multiple batches are combined and then distilled into o-methylphenyl ethyl ether.

[0059] Example 4

[0060] 800,000 parts of phenol-containing coal tar from coal pyrolysis of an energy enterprise in Xinjiang were added into the kettle of a distillation tower, 1,381 parts of water were first removed under normal pressure, and then distilled under reduced pressure (10 mmHg column) to obtain 10,805 parts of a light oil fraction <170°C, 110,301 parts of a phenol oil fraction at 170-230°C (including 14,606 parts of a phenol / o-cresol phenol oil fraction at 170-192°C), 16,445 parts of a tricresol fraction at 230-240°C, 14,643 parts of a catechol fraction at 240-250°C, 46,162 parts of a 5-indanol fraction at 250-270°C, and 74,405 parts of a resorcinol / hydroquinone fraction at 270-300°C.

[0061] 14606 samples of 170-192°C phenol / o-cresol phenol oil fraction were sampled and analyzed, with a phenol content of 51.3%, including 66.8% phenol, 30.5% o-cresol and 2.5% 2,6-xylenol in the phenol.

[0062] Add 14606 parts of phenol / o-cresol phenol oil fraction (obtained by distillation of phenol-containing coal tar) from the previous step and 12500 parts of 30% sodium hydroxide aqueous solution into the reactor, start stirring, raise the temperature to 60°C and stir for 1 hour, let stand for 1 hour to separate the layers, and obtain 19863 parts of aqueous solution, and separate 7236 parts of oil without phenolic compounds.

[0063] 5967 parts of dimethyl sulfate were added dropwise to the separated aqueous solution, the dropping temperature was controlled to be 55±5°C, the dropping time was about 3 hours, after the dropping was completed, the temperature was kept for reaction for 8 hours under slightly boiling conditions, and the sample analysis showed that the o-cresol content was 0.13%, and the conversion rate of o-cresol reached 99.8%. The temperature was lowered to 80°C and allowed to stand for stratification, the lower water layer was separated, and the material layer was retained. The water layer was extracted once with 100 parts of toluene, and the separated water layer was sent to the wastewater station. The material layer was added with 100 parts of water and stirred, and 15 parts of sulfuric acid was added dropwise for washing for 1 hour to remove impurities, and the layers were separated. The material layer was washed once with 100 parts of water, and the water was separated to obtain the material layer and the following treatment was performed.

[0064] The above material layer was added into a distillation kettle, and distilled under reduced pressure (-0.085MPa), with a reflux ratio of 10:1, and full reflux for 1.5 hours for every 6 hours of distillation, to collect 42.6 parts of the first portion (18.7 parts of anisole), 5669.8 parts of 99.82% anisole (5659.6 parts of anisole, 8.5 parts of o-methyl anisole, and 1.7 parts of others), 36.5 parts of the middle distillate (12.3 parts of anisole, 24.1 parts of o-methyl anisole, and 0.04 parts of others), 2487.6 parts of 99.73% o-methyl anisole (2.5 parts of anisole, 2481.7 parts of o-methyl anisole, 2.2 parts of m-p-methyl anisole, and 1.2 parts of others), and 250.3 parts of distillation kettle residual A (including 41.3 parts of o-methyl anisole and 206.7 parts of 2,6-dimethyl anisole).

[0065] 2503 parts of 10 batches of distillation still residue and 1 part of sulfuric acid were added to the distillation still, and vacuum distillation (-0.085MPa) was carried out with a reflux ratio of 15:1 and a total reflux of 1.5 hours for every 4 hours of distillation. 386.2 parts of 99.58% o-methyl anisole (384.6 parts of o-methyl anisole, 1.4 parts of 2,6-dimethyl anisole, and 0.2 parts of others), 48.7 parts of transition fraction (16.8 parts of o-methyl anisole, 31.8 parts of 2,6-dimethyl anisole, and 0.1 parts of others) and 1897.8 parts of 99.58% 2,6-dimethylbenzene (7.2 parts of o-methyl anisole, 1889.8 parts of 2,6-dimethyl anisole, and 0.8 parts of others) were collected. 125.9 parts (0.2 parts of o-methylanisole, 123.3 parts of 2,6-dimethylanisole, and 2.4 parts of others).

[0066] The middle fraction is incorporated into the distillation product of the next batch of etherified products; the transition fraction is incorporated into the distillation still residue A for distillation of o-methylanisole and 2,6-dimethylanisole; and the still residue B is incorporated into the distillation still residue A.

[0067] Comparative Example 1

[0068] Mix commercially available petrochemical-grade phenol and o-cresol in proportion (phenol 69%, o-cresol 31%) and add them to the reactor, 13,500 parts of 20% sodium hydroxide aqueous solution, start stirring, start dripping 3,000 parts of dimethyl carbonate, control the dripping temperature to 55±5°C, dripping time is about 4 hours, after dripping, keep warm for 10 hours under slightly boiling conditions, take samples for analysis, phenol 0.36%, phenol conversion rate reaches 99.5%, cool to 80°C and let stand for stratification, separate the lower water layer, and retain the material layer. Add 100 parts of toluene to the water layer for extraction once, send the separated water layer to the wastewater station, mix the toluene layer with the material layer, add 150 parts of water and stir, add 10 parts of sulfuric acid to wash for 1 hour to remove impurities, separate, wash the material layer with 150 parts of water, separate the water to obtain the material layer. Take samples of the material layer, use gas chromatography, trace sulfur and nitrogen analyzer and other analytical instruments to analyze the sulfur and nitrogen content, the sulfur and nitrogen content is 1.2ppm.

[0069] The above material layer was added into a distillation kettle, and 98.3 parts of toluene were recovered by atmospheric distillation, and then changed to vacuum distillation (-0.085MPa), with a reflux ratio of 10:1, and full reflux for 1.5 hours for every 6 hours of distillation. Under chromatographic analysis, 4163.2 parts of 99.8% anisole (99.81% anisole, 0.19% o-methyl anisole), 69.4 parts of intermediate fractions (58.74% anisole, 41.26% o-methyl anisole), 1701.7 parts of 99.9% o-methyl anisole (0.07% anisole, 99.93% o-methyl anisole), and 162.9 parts of distillation kettle residue (including 132.1 parts of o-methyl anisole) were accurately collected.

[0070] According to Comparative Example 1 and Comparative Example 1, the present invention further reduces the impurity content in the product phenyl alkyl ether and o-methylphenyl alkyl ether through the alkylation reaction, and the content of impurities such as nitrogen and sulfur in the purified product is low, and is at the same grade as the synthetic etherification product of petrochemical-grade phenol or o-cresol, that is, the present invention can obtain high-quality phenyl alkyl ether and o-methylphenyl alkyl ether products, thereby improving the product quality and application range.

[0071] In addition, mixed phenol is about 5,000 yuan / ton, 99.5% petrochemical phenol is 8,000 yuan / ton, and 99.5% petrochemical o-cresol is 15,000 yuan / ton. Therefore, using phenol / o-cresol phenol oil instead of petrochemical phenol and petrochemical o-cresol to produce anisole and o-methylanisole can reduce the raw material cost by more than 4,000 yuan per ton, which has good economic benefits.

[0072] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms may be for different embodiments or examples. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are contradictory.

[0073] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0074] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A method for producing phenyl alkyl ethers from a phenol / o-cresol fraction, characterized in that: The following steps are involved: (a) distillation and purification: distilling a phenol-containing raw material to obtain a mixture containing phenol and o-cresol, wherein the phenol-containing raw material includes crude phenol, mixed phenol, o-cresol fraction, m-cresol fraction, and phenol-containing coal tar; (b) etherification: alkylating the mixture containing phenol and o-cresol, and washing to obtain a material layer; (c) Separation: distilling the material layer to obtain products including phenyl alkyl ether and o-methylphenyl alkyl ether.

2. The method according to claim 1, characterized in that When the phenol-containing raw material is phenol-containing coal tar, the mixture containing phenol and o-cresol is a phenol / o-cresol phenol oil fraction, and a non-phenol component removal process is also included before step (b).

3. The method according to claim 2, characterized in that The non-phenol component removal process is to stir phenol / o-cresol phenol oil and alkaline aqueous solution at 30-80° C. for 1-2 hours, stand and separate into layers, remove the upper oil layer without phenolic compounds, and retain the lower water layer.

4. The method according to claim 3, characterized in that The alkaline aqueous solution is one or more of a sodium methoxide solution, a sodium ethoxide solution, a sodium hydroxide solution or a potassium hydroxide solution.

5. The method according to claim 3, characterized in that The step (b) is to drop an alkylating agent into the water layer, keep the temperature for 2 to 20 hours, and after the raw material conversion rate reaches more than 95%, stand to separate the water layer, and wash to obtain a material layer.

6. The method according to claim 1, characterized in that When the phenol-containing raw material is crude phenol, mixed phenol, o-cresol fraction and m-cresol fraction containing phenol and o-cresol, the mixture containing phenol and o-cresol is a phenol / o-cresol fraction with a distillation range of ≤192°C.

7. The method according to claim 6, characterized in that The step (b) is to drop an alkylating agent into the phenol / o-cresol fraction under a catalyst condition, keep the temperature for 2 to 20 hours, and after the raw material conversion rate reaches more than 95%, stand to separate the water layer, and wash to obtain a material layer.

8. The method according to claim 7, characterized in that The catalyst is one or more of aluminum oxide, magnesium oxide, and nickel oxide, or one or more of sodium methoxide solution, sodium ethoxide solution, sodium hydroxide solution, and potassium hydroxide solution.

9. The method according to claim 5 or 7, characterized in that The alkylating agent is one or more of iodoalkanes, chloroalkanes, brominatedalkanes, di-fatty sulfates, di-fatty carbonates, and fatty alcohols.

10. The method according to claim 5 or 7, characterized in that: The process of washing the material layer is to sequentially use 10% sulfuric acid and deionized water to wash the material layer.

Images