39 results about "Mixed cresols" patented technology

The invention discloses a novel method for separating an m-cresol and p-cresol mixture to obtain high-purity m-cresol and p-cresol. The method comprises the following steps: carrying out alkylation reaction on the m-cresol and the p-cresol as raw materials under the existence of an alkylating agent and a catalyst to obtain the mixed solution of 2-tertiary butyl-p-cresol and 6-tertiary butyl-m-cresol; rectifying the mixed solution to obtain the products of high-purity 2-tertiary butyl-p-cresol and 6-tertiary butyl-m-cresol; respectively carrying out dealkylation reaction and rectification on the obtained high-purity 2-tertiary butyl-p-cresol and 6-tertiary butyl-m-cresol under the existence of the catalyst to respectively obtain the products of the high-purity m-cresol and p-cresol; and recovering isobutene generated by dealkylation. The invention has high reaction conversion rate, high atom use ratio, low raw material consumption and production cost and reliable safety performance.

The invention provides a preparation method of a mixed cresol modified meta-xylylene diamine epoxy resin curing agent. The method comprises the following steps of: adding meta-xylylene diamine into an N2-charged reaction kettle; raising the temperature to 80-95 DEG C; adding hydroquinone; fully mixing; adding cardanol; keeping the temperature at 85-95 DEG C till a solution is clear and transparent; adding a catalyst; gradually adding polyformaldehyde in batches simultaneously; lowering the temperature to 70-80 DEG C; vacuumizing and dehydrating; after dehydrating, raising the temperature to 130-150 DEG C; undergoing a polymerization reaction; cooling to 70-85 DEG C; filtering the catalyst; diluting to 15-25 percent by using an organic solvent; and discharging to obtain the mixed cresol modified meta-xylylene diamine epoxy resin curing agent. A product prepared with the method has the advantages of stable performance, high curing speed, low toxicity, high transparency, unremarkable whitening phenomenon, nontoxicity and freeness of irritation, can be applied to underwater construction, and is a superior sea heavy-duty coating.

Relating to the field of m-cresol and p-cresol separation and its technology, the invention discloses a new method of separating an m-cresol and p-cresol mixture to obtain high-purity m-cresol and p-cresol. The method takes a m-cresol and p-cresol mixed solution and isobutene gas as the raw materials, and employs a solid supported acidic ionic liquid as the catalyst to carry out alkylation reaction in a fixed bed, the obtained alkylation product is separated to obtain mono-t-butyl cresol, which is subjected to de-tert-butylation, thus obtaining the high purity m-cresol and p-cresol.

A paint remover for the polyester paint or polyester imine paint coated copper wire is prepared from formic acid, trichloromethane, mixed cresol and additive through proportionally mixing and stirring.

The invention provides a method for production of high-purity m-cresol. The method comprises the following steps: (1) injecting a material I containing m-cresol and p-cresol into an adsorption unit for adsorptive separation to obtain an m-cresol product, wherein an adsorption unit comprises one or more adsorbent bed layer, and the at least one adsorbent bed layer comprises a molecular sieve adsorbent; (2) injecting a material II containing a desorbent into the adsorption unit to desorb the adsorbent bed layer in the adsorption unit so as to obtain a desorption material III, injecting the desorption material III into a separation unit, and performing separation to obtain a desorbent material IV and a mixed cresol material V; (3) returning the desorbent material IV obtained through separation in the step (2) into the adsorption unit for recycling; and (4) injecting the mixed cresol material V obtained through separation in the step (2) into an isomerization reaction unit for a reaction to obtain an isomerization product material VI, and returning the isomerization product material VI into the desorption unit.

The invention relates to a separation and purification method of m-cresol. The separation and purification method comprises the following steps: a) complexing: adding mixed cresol, urea and a mixed solvent formed by toluene and liquid alkane into a reactor, stirring, heating to increase the temperature to 65-90 DEG C, performing heat preservation for 1-2h, reducing the temperature to 40-60 DEG C, then cooling and crystallizing at the temperature of 0-20 DEG C for 1-2h, and filtering to obtain a complex solid and filtrate A; and b) decomplexing: adding the complex solid obtained in the step a) into an ether type solvent, stirring at the temperature of 10-60 DEG C, performing decomplexing reaction for 0.5-3h, and filtering to obtain urea and filtrate B; and performing decompression rectification on the filtrate B to obtain m-cresol. The method for separating m-cresol from mixed cresol is high in product purity, simple in process, low in solvent consumption, high in recovery rate and low in energy consumption and can operate at normal pressure, prevent the production of three wastes in a separation process and realize recycling of resources, so that the method is environment-friendly.

The invention discloses a method for separation and purification of p-cresol. The method comprises the following steps: 1) complexation: adding toluene and a complexing agent of oxalic acid into a reaction kettle, heating, adding mixed cresol, insulating for reaction, and filtering to obtain a cresol- oxalic acid complex crude product; 2) purification: adding the p-cresol-oxalic acid complex crude product into a purification solvent, stirring and filtering to obtain a p-cresol-oxalic acid complex; 3) decomplexation: adding the p-cresol-oxalate complex into water, insulating for reaction, separating an upper organic phase while hot, extracting the lower aqueous phase by toluene, and merging the extraction liquid into the upper organic phase; and 4) distillation: distilling the upper organic phase to remove solvent so as to obtain p-cresol. Compared with the prior art, a purification step is added to ensure that the final isolated p-cresol has purity of no less than 99%; the amount of organic solvents is reduced, the complexation step employs water, and the organic solvent and water involved in the separation process can be used indiscriminately, thereby saving cost.

The invention discloses a high-pressure fixed bed alkylation method for mixed m-cresol and p-cresol. The method comprises the following steps: pressurizing and liquefying alkylating agents, injecting the alkylating agents and mixed cresol into a reactor, maintaining the pressure of a fixed bed reactor to be 1.7-4.2MPa at the temperature of 50-110 DEG C, reacting under the space velocity of 0.1-5h<-1>, thereby obtaining a self-polymerized product of isobutene, mono-tert-butyl products of m-cresol and p-cresol and di-tert-butyl products of m-cresol and p-cresol, wherein the reactor is the fixed bed reactor; the alkylating agents refer to isobutene and aids; the volume of the aids accounts for 70-90% of the total volume of the alkylating agents; and a molar ratio of the isobutene to the mixed m-cresol and p-cresol is (0.5-3):1. According to the method disclosed by the invention, the utilization efficiency of the raw materials is improved, the conversion rate of the m-cresol in the method can reach 94.22%, and the conversion rate of the p-cresol can reach 89.46%.

The invention relates to a preparation method of 2, 6-di-tert-butyl p-cresol, and belongs to the technical field of organic chemical synthesis. According to the method, a modified mesoporous silica loaded Nb/Mo/Cu three-metal active center catalyst is used as a catalyst, m-cresol, p-cresol and isobutene are mixed to be used as raw materials, ultrasonic cavitation is carried out in the catalytic reaction process, and then 2, 6-di-tert-butyl p-cresol is prepared. Mixed cresol is used as a raw material, so that a cost is reduced, during preparation of 2, according to the method, m-cresol is separated while 2, 6-di-tert-butyl-p-cresol is separated, by research, it is discovered that the modified mesoporous silica loaded Nb/Mo/Cu three-metal active center catalyst has a synergistic catalytic effect of the three-metal active center, the conversion rate of the mixed cresol and the selectivity of the di-tert-butyl cresol are greatly improved, especially, the selectivity of the 2, 6-di-tert-butyl-p-cresol is improved, impurities such as 2-tert-butyl-p-cresol and 6-tert-butyl-m-cresol are reduced, meanwhile, under the action of ultrasonic cavitation, a liquid-gas reaction is promoted to forma microreactor in micropores in a solid catalyst, the catalytic activity is greatly improved, the gas-liquid two-phase mass transfer efficiency and heat transfer area are increased, and the conversion rate of raw materials is further increased.

The invention relates to a method for separating cresol to obtain high purity m-cresol by adopting a complex separation method. The method for separating the cresol to obtain the high purity m-cresol by adopting the complex separation method adopts amide as a complex, is specifically combined with the cresol in an organic solvent system after being mixed and heated with mixed cresol, then amide-m-cresol crystals are crystallized to continuously separate out by controlling the temperature of the organic solvent system, high purity m-cresol is obtained through a mode that m-cresol is crystallized, separated and released at a temperature, and the purity of the m-cresol can be above 99.5%. The method for separating the cresol to obtain the high purity m-cresol by adopting the complex separation method has the advantages that the purity of the m-cresol is high, complexes are easy to obtain and can be recycled and the process step is simple and easy to operate and the like. The method for separating the cresol to obtain the high purity m-cresol by adopting the complex separation method has great guidance value in separation, purification and preparation of the m-cresol.

The invention discloses a method for preparing p-hydroxybenzaldehyde and m-hydroxybenzaldehyde from mixed cresol. The method comprises the following steps of: 1, oxidization: adding sodium hydroxide, calcium oxide and a catalyst to mixed cresol and methanol which are used as raw materials for reacting under the conditions of heating and pressurizing, thus obtaining a mixture of p-hydroxybenzaldehyde and m-hydroxybenzaldehyde; and separating the mixture to obtain the crude product of the mixture of p-hydroxybenzaldehyde and m-hydroxybenzaldehyde; 2, refining: refining the crude product of the mixture of p-hydroxybenzaldehyde and m-hydroxybenzaldehyde to obtain the mixture of p-hydroxybenzaldehyde and m-hydroxybenzaldehyde; and 3, separation: sublimating the mixture of p-hydroxybenzaldehyde and m-hydroxybenzaldehyde by virtue of the property of the p-hydroxybenzaldehyde easy to sublimate under heating, and condensing the sublimate, thus obtaining the p-hydroxybenzaldehyde in a condensation tank and keeping the m-hydroxybenzaldehyde in a sublimation tank; and finally, separating out the p-hydroxybenzaldehyde and the m-hydroxybenzaldehyde from each other.

The invention relates to a preparation method of high-purity tricresyl phosphate. The preparation method comprises the following steps: (S1) with mixed cresol and phosphorus oxychloride as the raw materials and Lewis acid as a catalyst, simultaneously adding the raw materials and the catalyst into a reactor, and reacting to obtain a crude product of tricresyl phosphate, wherein the mass percentageof o-cresol in mixed cresol is lower than 0.01%; (S2) carrying out reduced-pressure distillation on the crude product of tricresyl phosphate until the acid value of the crude product of tricresyl phosphate is less than or equal to 3mgKOH/g; and (S3) carrying out molecular distillation on the tricresyl phosphate crude product with the acid value less than or equal to 3mgKOH/g. The preparation method is simple, convenient, low in production cost, high in product purity and suitable for industrial production. High-purity tricresyl phosphate prepared by virtue of the preparation method is suitable for the fields of aviation fuel base oil, plasticizers, flame retardants, lubricating oil extreme-pressure anti-wear agents and the like.

The invention provides a new method for preparing chemical intermediates by using mixed o/m/p-cresol. The method comprises the following steps of: taking mixed solution of o-cresol, m-cresol and p-cresol a raw material, performing alkylation on the mixed solution in the presence of an alkylating agent and a catalyst to obtain mixed solution of 6-tertbutyl-o-cresol, 6-tertbutyl-m-cresol and 2-tertbutyl-o-cresol, and rectifying the mixed solution to obtain high-purity chemical intermediate products of the 6-tertbutyl-o-cresol, the 6-tertbutyl-m-cresol and the 2-tertbutyl-o-cresol. The method has high reaction conversion rate, and can improve the utilization rate of atoms and reduce the raw material consumption and the production cost.

The invention relates to a preparation method of high-purity 2,6-di-tert-butyl p-cresol, and belongs to the technical field of organic chemical synthesis. According to the method, ethanol and water are recrystallized twice, so that the purity of the product is improved, and the purity of the target product BHT can reach 99.99% or above; besides, water and ethanol separated from the primary motherliquor through the rectifying tower can be recycled, the rectified mother liquor is guided into a crystallization system to be recycled, and the yield of 2,6-di-tert-butyl-p-cresol is increased; meanwhile, the BHT concentration of the secondary mother liquor is detected, recrystallization is conducted, and the yield of BHT reaches 99.89% or above. Secondly, under the catalytic action of the modified mesoporous silica supported Nb/Mo/Cu three-metal active center catalyst, the conversion rate of mixed cresol and the selectivity of di-tert-butyl cresol are greatly improved, and the conversion rate of the raw materials is further improved under the synergistic effect of ultrasonic cavitation.

The invention particularly relates to a solid acid catalyst and a method for producing m-cresol. The invention relates to a method for producing m-cresol, the method comprises the following steps: 1, heating a mixture raw material containing p-cresol and o-cresol by a preheater, and introducing the mixture raw material into a fixed bed reactor or a simulated moving bed reactor for reaction; 2, under the reaction conditions that the reaction pressure ranges from 0.1 MPa to 12.0 MPa, the temperature ranges from 180 DEG C to 450 DEG C, and the weight space velocity WHSV ranges from 1.0 h <-1 > to 12.0 h <-1 >, generating a reaction product containing o-cresol, m-cresol and p-cresol through the reaction under the action of the solid acid catalysts according to the claim 1 and the claim 6; and 3, separating the reaction product through a rectifying tower to obtain o-cresol and m-cresol and p-cresol mixture, and circulating the o-cresol which is not reacted and converted to serve as a reaction raw material to enter the reactor. The method has the advantages of high reaction efficiency, few dehydroxylation/methyl side reactions, low loss rate of cresol, low surface coking and inactivation of the catalyst, higher content of m-cresol and remarkable economic benefits.

The invention relates to a solid acid catalyst and a method for producing cresol by using the same, wherein the method comprises the steps: taking phenol as a raw material, carrying out hydroalkylation reaction on the phenol and methanol and/or dimethyl ether, and generating a product containing o-cresol, m-cresol and p-cresol mixture in a fixed bed reactor or a fluidized bed reactor, wherein porous solid acid which is modified by metal and has medium acidity is used as a hydroalkylation reaction catalyst. Compared with an alkylation reaction process of phenol and methanol used in current industrial production, the cresol production process provided by the invention has the characteristics of high reaction conversion rate, high selectivity of m-cresol and p-cresol with high added value, low energy and material consumption, good operation stability and environmental friendliness.

The invention discloses a preparation method of an emulsion-type highly-dispersed antioxidant. The preparation method comprises the following steps: performing a phenol methylation reaction on phenol and methyl alcohol under the action of a catalyst Cs/SiO2 to obtain mixed cresol as a product; adding methylbenzene and oxalic acid as a complexing agent into a reaction kettle, adding the mixed cresol, and filtering to obtain a filtrate and a white granular p-cresol-oxalic acid complex; adding the p-cresol-oxalic acid complex granules into a mixed solution of methylbenzene and methyl alcohol, and filtering to obtain the p-cresol-oxalic acid complex; adding the obtained p-cresol-oxalic acid complex into water, and separating to obtain an upper organic phase and a lower water phase; distilling the upper organic phase to remove a solvent to obtain p-cresol; adding the obtained p-cresol into silicon sol with the solid content of 40-50%, and stirring to obtain the emulsion-type highly-dispersed antioxidant. The emulsion-type highly-dispersed antioxidant is good in dispersion and has excellent oxidation resistance.