CN112569936B - Novel metal-doped catalyst for selectively synthesizing bisphenol F, and preparation method and application thereof - Google Patents

Abstract

The invention provides a novel metal-doped catalyst for selectively synthesizing bisphenol F, a preparation method and application thereof, which can solve the problem of TiO₂The technical problem that the catalytic activity of the photocatalyst used for the synthesis reaction of bisphenol F needs to be further improved is solved. A preparation method of a novel metal-doped catalyst for selectively synthesizing bisphenol F is characterized by comprising the following steps: comprises the following steps of S1, adding tetrabutyl titanate into isopropanol to prepare solution A, and adding Sn (OH)₄Dissolving the solution and NaOH in isopropanol to prepare solution B; s2, dropwise adding the solution B into the solution A; s3, carrying out hydrothermal reaction on the solution prepared in the S2; s4, carrying out suction filtration on the solid-liquid mixture after the S3 hydrothermal reaction, and carrying out solid phase filtrationPickling a sample, and backwashing by distilled water; and S5, drying the solid phase sample cleaned in the S4, and then burning to obtain the metal doped catalyst. The metal-doped catalyst provided by the invention has higher catalytic performance, is environment-friendly and saves energy.

Description

Novel metal-doped catalyst for selectively synthesizing bisphenol F, and preparation method and application thereof

Technical Field

The invention relates to the technical field of catalysts for synthesizing bisphenol F, in particular to a novel metal-doped catalyst for selectively synthesizing bisphenol F, and a preparation method and application thereof.

Background

Bisphenol F is an important chemical intermediate and is obtained by the hydroxyalkylation condensation reaction of phenol and formaldehyde. The product mainly comprises 2,2 '-bisphenol F, 2, 4' -bisphenol F and 4,4 '-bisphenol F, and the total three isomers are composed, wherein the performance of the 4, 4' -bisphenol F isomer is the best. Because of the unique chemical structure, when the product is used for synthesizing epoxy resin, polyester resin and polycarbonate resin and used as a phenolic resin modifier and a flame retardant, the heat resistance, the moisture resistance, the insulativity, the processability and the injection molding pouring performance of the product are far superior to those of similar products prepared by taking bisphenol A as a raw material. The catalyst is one of important process conditions in a bisphenol F synthesis process, people want to use the process conditions of bisphenol A synthesis for reference at first and select strong inorganic acid as the catalyst, but the reaction process has the defects of strong corrosivity, volatile hydrogen chloride gas, increased side reaction products such as chloroethylene ether, chloromethyl phenol, sulfonated products and the like, and the problems of difficult separation of an aqueous solution and an organic phase and the like, so people finally need to search for the catalyst with the characteristics of low corrosivity, high catalytic activity, easy recovery and the like.

The novel photocatalyst can provide a green high-efficiency good formula for the synthesis of bisphenol F. The photocatalytic reaction is one which is carried out under conditions requiring light irradiationAnd (4) carrying out chemical reaction. In the reaction, light energy is used as a main energy source, so that reactant molecules generate extranuclear electron transition after absorbing electromagnetic radiation with specific wavelength, the molecules are converted into an excited state from a normal state, and then participate in chemical reaction for generating a target product. A common photocatalyst is TiO₂、C₃N₄ZnO, CdS, etc., of which TiO is especially₂The paint has the advantages of stable physicochemical property, white color, no toxicity, no odor, low preparation cost, light corrosion resistance and the like, and is highly advocated. To improve TiO₂Photocatalytic activity, we usually need to design photocatalysts, mainly including: morphology design, doping, semiconductor compounding, and the like. The doping ions are filled into the titanium dioxide crystal lattice gaps by a physical method or a chemical method, so that the charges carried by the crystals are redistributed or the crystal structure of the crystals is changed, and the movement of carriers is purposefully improved or the energy band structure of the titanium dioxide is changed. The introduction of metal ions into semiconductor catalysts can be achieved mainly by physical and chemical means. The addition of proper metal ions can improve the crystal form defect of the catalyst and increase the separation efficiency of photo-generated electrons and holes, thereby achieving the purpose of improving the catalytic activity. The invention designs and synthesizes the titanium dioxide catalyst doped with metal ions, and introduces Sn in the preparation process of the titanium dioxide nanobelt⁴⁺、Cu²⁺、Fe³⁺The modified catalyst is used for the synthesis reaction of bisphenol F, so that the yield of the reaction can be improved, and the cost is saved; the catalyst is rarely reported at present.

Disclosure of Invention

The invention provides a novel metal-doped catalyst for selectively synthesizing bisphenol F, a preparation method and application thereof, which can solve the problem of TiO₂The technical problem that the catalytic activity of the photocatalyst used for the synthesis reaction of bisphenol F needs to be further improved is solved.

The technical scheme is that the preparation method of the novel metal-doped catalyst for selectively synthesizing the bisphenol F is characterized by comprising the following steps of: comprises the following steps of (a) carrying out,

s1, adding 1-60 mL of tetrabutyl titanate into 10-250 mL of isopropanol to prepare solution A,

mixing 10-50 mg Sn (OH)₄Or Cu (OH)₂Or Fe (OH)₃Dissolving the mixed solution and 40-450 mg of NaOH into 10-250 mL of isopropanol to prepare a solution B;

s2, dropwise adding the solution B into the solution A, and stirring continuously;

s3, carrying out hydrothermal reaction on the solution prepared in the S2, and obtaining 170^oKeeping the temperature for 24-48h under C;

s4, carrying out suction filtration on the solid-liquid mixture after the hydrothermal reaction of S3, and washing the solid-phase sample with acid and then with distilled water again until the pH is = 7;

s5, washing the solid phase sample of S4 at 80^oDrying for 24-48h under C, and then burning at 10%^oC·min^-1Is increased to 650^oAnd C, preserving the heat for 4-12 hours to obtain the metal doped catalyst.

The invention also provides a novel metal-doped catalyst for selectively synthesizing bisphenol F, which is characterized in that: the metal-doped catalyst is prepared by the method.

The invention also provides an application of the metal-doped catalyst in the synthesis of bisphenol F, wherein the bisphenol F is 4, 4' -bisphenol F, and the metal-doped catalyst is characterized in that: the synthesis of bisphenol F comprises the following steps,

s1', adding 1g of phenol and 100mg-1g of metal doped catalyst into a reaction container, adding dimethylbenzene to dissolve the phenol, slowly dropwise adding 0.2 g-5 g of 37% formaldehyde aqueous solution, stirring and reacting for 2-72 hours at room temperature, and providing a stable light source for irradiation;

s2 ', filtering the mixed solution obtained in the step S1', standing the filtrate for layering, taking the oil phase obtained after layering as a reaction product layer, removing the solvent and phenol from the reaction product by rotary evaporation under reduced pressure to obtain a crude product, finally recrystallizing the crude product with xylene, and filtering out pure bisphenol F.

The reaction equation for the synthesis of bisphenol F is as follows:

。

compared with the traditional catalytic process, the process for synthesizing the bisphenol F by using the metal-doped catalyst provided by the invention has higher catalytic performance, and the catalyst can be recovered, is environment-friendly and saves energy.

In addition, the invention also provides application of the metal-doped catalyst in the synthesis of 3- (4-chlorphenyl) -1-phenyl propane-1-ketone by the reaction of 4-chlorobenzyl alcohol and 1-phenyl ethanol. By applying the metal-doped catalyst, the reaction achieves the yield of more than 90% and the chemical selectivity of more than 90%.

Drawings

FIG. 1 shows Sn as a metal⁴⁺ Doped TiO 2₂XRD pattern of the catalyst.

FIG. 2 shows Cu metal²⁺Doped TiO 2₂XRD pattern of the catalyst.

FIG. 3 is a view of metallic Cu²⁺Doped TiO 2₂Scanning electron micrographs of the catalyst.

FIG. 4 shows metallic Fe³⁺Doped TiO 2₂XRD pattern of the catalyst.

Detailed Description

In the following, the applicant has carried out some specific experiments on the present invention, which show the preparation of metal-doped titanium dioxide catalysts and the specific steps for the synthesis of bisphenol F using such photocatalysts. These are merely intended to be exhaustive of the invention and do not limit the scope of the invention in any way.

Example one

Metallic Sn⁴⁺ Doped TiO 2₂The preparation method of the catalyst comprises the following process steps: 2 mL of tetrabutyltitanate was added to 25mL of isopropyl alcohol to prepare solution A, and 40 mg of NaOH and 50mg of Sn (OH)₄Dissolving the mixture into 25mL of isopropanol to prepare a solution B, and then dropwise adding the solution B into the solution A without stirring. The solution obtained in the above process was transferred to a 100 mL hydrothermal kettle, 170^oAnd (5) preserving the heat for 24 hours under the condition of C. After the hydrothermal reaction, the mixture is taken out and cooled to room temperature, and 0.1 mol.L of the mixture is used^-1The hydrochloric acid solution was washed with distilled water (20 x3 mL) three times to pH = 7. The sample obtained by suction filtration is at 80^oDrying for 48 hours under C, putting the mixture into a muffle furnace for burning, and burning the mixture by 10 degrees^oC·min^-1Is increased to 650^oC, preserving heat for 12 hours to obtain metal Sn⁴⁺Doped TiO 2₂Catalyst and process for preparing same。

X-ray diffraction characterization (XRD) of the product of the above process: as shown in FIG. 1, the peak position of the curve is found to be 25.26^oAnd 27.48^oTwo types of products of titanium dioxide appear, which respectively correspond to anatase type titanium dioxide and rutile type titanium dioxide, and the signals of rutile type products are stronger. Thus, the method can prepare the metal Sn with mixed crystal form⁴⁺ Doped TiO 2₂A catalyst.

The specific steps for synthesizing 4, 4' -bisphenol F are as follows: 1g of phenol is mixed with metallic Sn⁴⁺The doped titanium dioxide catalyst of 100mg is added into a three-neck flask, 20mL of dimethylbenzene is added to dissolve phenol, the mixture is stirred and reacted at room temperature, and then 0.2g of 37% formaldehyde aqueous solution is slowly dropped. The reaction was placed in a steady light source (100W fluorescent lamp, lamp tube placed in a cold trap with condensed water circulation) and stirred for 12 hours. Filtering the obtained mixed solution, recovering the photocatalyst, standing the filtrate, taking the oil phase obtained after layering as a reaction product layer, carrying out reduced pressure rotary evaporation to remove the solvent and phenol to obtain a crude product, finally recrystallizing with xylene once, and filtering out 4, 4' -bisphenol F, wherein the yield is as follows: 65 percent.

Example two

Metallic Cu²⁺Doped TiO 2₂The preparation method of the catalyst comprises the following process steps: 10 mL of tetrabutyltitanate was added to 200 mL of isopropyl alcohol to prepare a solution A, and 100mg of NaOH and 50mg of Cu (OH) were added, respectively₂Dissolving the mixture into 150 mL of isopropanol to prepare a solution B, and then dropwise adding the solution B into the solution A without stirring. The solution obtained in the above process was transferred to a 500 mL hydrothermal kettle, 170^oAnd (5) preserving the heat for 48 hours under the condition of C. After the hydrothermal reaction, the mixture is taken out and cooled to room temperature, and 0.1 mol.L of the mixture is used^-1The hydrochloric acid solution was washed with distilled water (20 x3 mL) three times to pH = 7. The sample obtained by suction filtration is at 80^oDrying for 24 hours under C, putting the mixture into a muffle furnace for burning, and burning by 10^oC·min^-1Is increased to 650^oC, preserving heat for 12 hours to obtain metal Cu²⁺Doped TiO 2₂A catalyst.

X-ray diffraction characterization (XRD) of the product of the above process: as shown in FIG. 2, from25.36^oThe diffraction peak appeared and it is known that Cu is doped²⁺ The production method of (1) promotes the production of anatase type titanium dioxide, and no crystal phase diffraction peak of CuO is found in the figure, indicating that copper ions enter into the crystal lattice of anatase. Thus, the method can prepare the metal Cu²⁺Doped TiO 2₂A catalyst.

Field emission scanning electron microscopy characterization (SEM) of the product of the above process: as shown in FIG. 3, when the copper-doped sample with a better crystal form is characterized by a scanning electron microscope, the whole structure of the copper-doped sample is an agglomerated nano-belt-shaped structure and is approximately rod-shaped at high power.

The specific steps for synthesizing 4, 4' -bisphenol F are as follows: 1g of phenol was mixed with 200mg of metallic Cu²⁺Doped TiO 2₂The catalyst was added to a three-necked flask, 40mL of xylene was added to dissolve phenol, the mixture was stirred at room temperature and reacted, and then 0.3 g of 37% aqueous formaldehyde solution was slowly dropped. The reaction was placed under irradiation of a steady light source (100W fluorescent lamp, lamp tube placed in a cold trap with condensed water circulation) and stirred for 16 hours. Filtering the obtained mixed solution, recovering the photocatalyst, standing the filtrate, taking the oil phase obtained after layering as a reaction product layer, carrying out reduced pressure rotary evaporation to remove the solvent and phenol to obtain a crude product, finally recrystallizing with xylene once, and filtering out pure bisphenol F. Yield: 89 percent.

EXAMPLE III

Metallic Fe³⁺Doped TiO 2₂The preparation method of the catalyst comprises the following process steps: 20mL of tetrabutyltitanate was added to 120 mL of isopropyl alcohol to prepare a solution A, and 80 mg of NaOH was mixed with 30 mg of Fe (OH)₃Dissolved in 110 mL of isopropanol as a solution B, and then the solution B was added dropwise to the solution A with stirring. The solution prepared in the above process was transferred to a 1000mL hydrothermal kettle, 170^oAnd (5) preserving the heat for 48 hours under the condition of C. After the hydrothermal reaction, the mixture is taken out and cooled to room temperature, and 0.1 mol.L of the mixture is used^-1The hydrochloric acid solution was washed with distilled water (20 x3 mL) three times to pH = 7. The sample obtained by suction filtration is at 80^oDrying for 48 hours under C, putting the mixture into a muffle furnace for burning, and burning the mixture by 10 degrees^oC·min^-1Is increased to 650^oC, preserving the heat for 8 hours to obtain metal-doped dioxideTitanium.

X-ray diffraction characterization (XRD) of Fe-Ti: as shown in FIG. 4, it can be observed from the diffraction pattern that Fe is doped³⁺ The titanium dioxide mainly exists in an anatase crystal form, and only a small amount of by-product sodium titanate is contained, so that the iron ions have a certain effect on the generation of the titanium dioxide with a single configuration.

The specific steps for synthesizing 4, 4' -bisphenol F are as follows: 1g of phenol was mixed with 320mg of metallic Fe³⁺Doped TiO 2₂The catalyst was added to a three-necked flask, 50mL of xylene was added to dissolve phenol, the mixture was stirred at room temperature and reacted, and then 0.60 g of 37% aqueous formaldehyde solution was slowly dropped. The reaction was placed under irradiation of a steady light source (100W fluorescent lamp, lamp tube placed in a cold trap with condensed water circulation) and stirred for 19 hours. Filtering the obtained mixed solution, recovering the photocatalyst, standing the filtrate, taking the oil phase obtained after layering as a reaction product layer, carrying out reduced pressure rotary evaporation to remove the solvent and phenol to obtain a crude product, finally recrystallizing with xylene once, and filtering out pure bisphenol F. Yield: 78 percent.

Example four

The selective synthesis of 4-chlorobenzyl alcohol and 1-phenyl ethanol for reaction to synthesize substituted ketone compounds comprises the following process steps: 100mg of 4-chlorobenzyl alcohol and 120mg of 1-phenyl ethanol were placed in a 25mL reaction tube, and 200mg of Sn metal prepared in example one was added⁴⁺ Doped TiO 2₂Adding a catalyst and 50mg KOH, then adding 3mL of toluene, placing the mixture in an oil bath kettle at 120 ℃ for reaction for 6 h, after the reaction is finished, cooling the mixture to room temperature, adding ethyl acetate and water for extraction for 3 times, separating liquid, collecting an organic phase, evaporating the organic phase to dryness by using a rotary evaporator, and separating by using silica gel column chromatography to obtain a pure product of 3- (4-chlorophenyl) -1-phenylpropan-1-one with the yield of 95%. The product selectivity was 92%.

Characterization data for 3- (4-chlorophenyl) -1-phenylpropan-1-one:¹H NMR (400 MHz, CDCl₃) δ 7.98 – 7.93 (m, 2H), 7.58 – 7.52(m, 1H), 7.51 – 7.43 (m, 2H), 7.28 – 7.213 (m, 2H), 7.21 – 7.16 (m, 2H), 3.27 (t, J = 7.2 Hz, 2H), 3.03 (t, J = 7.6 Hz, 2H).¹³C NMR (101 MHz, CDCl₃) δ 198.7, 139.7, 136.6, 133.1, 131.6, 130.3, 129.8, 128.5, 127.9, 40.1, 29.3.

EXAMPLE five

The selective synthesis of 4-chlorobenzyl alcohol and 1-phenyl ethanol for reaction to synthesize substituted ketone compounds comprises the following process steps: 100mg of 4-chlorobenzyl alcohol and 120mg of 1-phenyl ethanol were placed in a 25mL reaction tube, and 200mg of metallic Cu obtained in example 2 was added²⁺Doped TiO 2₂Adding a catalyst and 40 mg KOH, then adding 3mL of toluene, placing the mixture in an oil bath kettle at 110 ℃ for reaction for 12h, after the reaction is finished, cooling the mixture to room temperature, adding ethyl acetate and water for extraction for 3 times, separating liquid, collecting an organic phase, evaporating the organic phase by using a rotary evaporator, and separating by using silica gel column chromatography to obtain a pure product of 3- (4-chlorophenyl) -1-phenylpropan-1-one with the yield of 91%. The product selectivity was 90%.

Claims (1)

1. The application of a metal-doped catalyst in the synthesis of bisphenol F is characterized in that:

the preparation method of the metal-doped catalyst comprises the following steps,

s1, adding 1-60 mL of tetrabutyl titanate into 10-250 mL of isopropanol to prepare solution A,

mixing 10-50 mg Sn (OH)₄Or Cu (OH)₂Or Fe (OH)₃Dissolving the mixed solution and 40-450 mg of NaOH into 10-250 mL of isopropanol to prepare a solution B;

s2, dropwise adding the solution B into the solution A, and stirring continuously;

s3, carrying out hydrothermal reaction on the solution prepared in the S2, and obtaining 170^oKeeping the temperature for 24-48h under C;

s4, carrying out suction filtration on the solid-liquid mixture after the hydrothermal reaction of S3, and washing the solid-phase sample with acid and then with distilled water again until the pH is = 7;

s5, washing the solid phase sample of S4 at 80^oDrying for 24-48h under C, and then burning at 10%^oC·min^-1Is increased to 650^oC, preserving heat for 4-12 h to obtain a metal-doped catalyst;

the bisphenol F is 4, 4' -bisphenol F, and the synthesis of the bisphenol F comprises the following steps,

s1', adding 1g of phenol and 100mg-1g of metal doped catalyst into a reaction container, adding dimethylbenzene to dissolve the phenol, slowly dropwise adding 0.2 g-5 g of 37% formaldehyde aqueous solution, stirring and reacting for 2-72 hours at room temperature, and providing a stable light source for irradiation;

s2 ', filtering the mixed solution obtained in the step S1', standing the filtrate for layering, taking the oil phase obtained after layering as a reaction product layer, removing the solvent and phenol from the reaction product by rotary evaporation under reduced pressure to obtain a crude product, finally recrystallizing the crude product with xylene, and filtering out pure bisphenol F.

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