A continuous production process for the preparation of sandalwood 803

Abstract

This invention relates to a continuous production process for the preparation of sandalwood 803. The preparation method of the phosphate catalyst includes the following steps: dissolving Zr(NO3)4·5H2O and Ce(NO3)3·6H2O in water to prepare a Zr-Ce nitrate mixture; dissolving phosphoric acid and / or its acidic salt in water to obtain a phosphoric acid and / or its acidic salt solution; adding the phosphoric acid and / or its acidic salt solution to the Zr-Ce nitrate mixture, adjusting the pH, stirring, allowing it to settle, filtering, washing, drying, and calcining to obtain the phosphate catalyst, thus completing the reaction. Compared with the prior art, this invention provides a phosphate catalyst with high safety, high activity, high stability, and strong acidity, achieving a high-yield conversion of phenol camphene, increasing the content of meta-terpene phenols, and thus increasing the content of terpene cyclohexanol in sandalwood 803. It can also be used stably and for a long time in a fixed-bed gas-phase reaction process.

Description

Technical Field

[0001] This invention relates to the field of sandalwood 803 preparation technology, and in particular to a continuous production process for sandalwood 803 preparation. Background Technology

[0002] Sandalwood 803 is a colorless to slightly yellow viscous liquid with a long-lasting sandalwood aroma. It is an important monomeric fragrance ingredient, used extensively in various perfumes, particularly in incense. The terpene cyclohexanol in sandalwood 803 mixtures is a product with a strong sandalwood scent. In recent years, demand has increased dramatically with the development of the cosmetics industry. Traditionally, it is produced by condensing camphene and guaiacol followed by hydrogenation. However, during hydrogenation, the -OCH3 group on the guaiacol molecule is removed by hydrogenolysis, and guaiacol is relatively expensive. Direct condensation of phenol and camphene can significantly reduce costs. Raney nickel is often used as a hydrogenation catalyst in the process; its high reactivity leads to the removal of the hydroxyl group on the phenol molecule by hydrogenolysis.

[0003] The traditional process for producing sandalwood 803 by condensing phenol and camphene employs a batch reactor production method. Phenol and camphene are fed into the reactor as raw materials, with clay added as a catalyst for a liquid-phase reaction. The terpenoid phenols generated by alkylation are then placed in a high-pressure reactor and hydrogenated under high pressure to produce sandalwood 803. This process involves intermittent production according to a fixed formula, resulting in low production efficiency, large space requirements, and high labor costs. Furthermore, the low temperature of the liquid-phase alkylation reaction leads to a low content of meta-terpenoid phenols in the alkylation product. This is because the clay catalyst used in the batch production has poor stability and a short lifespan, making it unsuitable for continuous fixed-bed gas-phase reaction production. Therefore, developing a catalyst with high safety, high activity, high stability, and strong acidity for use in continuous fixed-bed gas-phase reaction production can effectively improve the yield and quality of sandalwood 803, possessing significant industrial application value. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the existing technology, such as low yield and short catalyst life in the fixed-bed gas-phase alkylation synthesis of terpene phenols, and to provide a continuous production process for the preparation of sandalwood 803. This process yields a phosphate catalyst with high safety, high activity, high stability, and strong acidity, achieving a high-yield conversion of phenol camphene, increasing the content of meta-terpene phenols, and thus increasing the content of terpene cyclohexanol in sandalwood 803. Furthermore, this process can be used stably and for a long time in a fixed-bed gas-phase reaction process.

[0005] The objective of this invention can be achieved through the following technical solutions:

[0006] One of the technical solutions of the present invention is to provide a method for preparing a phosphate catalyst for the preparation of sandalwood 803, comprising the following steps:

[0007] Zr(NO3)4·5H2O and Ce(NO3)3·6H2O were dissolved in water to prepare a Zr-Ce nitrate mixture.

[0008] Dissolve phosphoric acid and / or its acid salts in water to obtain a solution of phosphoric acid and / or its acid salts;

[0009] The phosphoric acid and / or its acidic salt solution is added to the Zr-Ce nitrate mixture, the pH is adjusted, the mixture is stirred and allowed to stand to precipitate, then filtered, washed, dried and calcined to obtain the phosphate catalyst, and the reaction is complete.

[0010] Further, the molar ratio of Zr(NO3)4·5H2O and Ce(NO3)3·6H2O is 0.1~8:1, preferably 0.1~4:1, such as 4:1, 2:1, 1:1, 0.5:1, 0.25:1, 0.1:1;

[0011] The concentration of Zr(NO3)4·5H2O in the Zr-Ce nitrate mixture is 0.01~1 mol / L.

[0012] Furthermore, the phosphoric acid and / or its acid salts include one or more of H3PO4, NH4H2PO4, and (NH4)2HPO4;

[0013] The concentration of the phosphoric acid and / or its acidic salt solution is 0.01~1 mol / L.

[0014] Furthermore, the actual amount of phosphoric acid and / or its acid salt added is 0.75 to 1.25 times the theoretical molar amount of phosphoric acid and / or its acid salt required for the complete precipitation of Zr(NO3)4·5H2O and Ce(NO3)3·6H2O.

[0015] Furthermore, during the pH adjustment process, ammonia water is used to adjust the pH to 6-8;

[0016] The calcination temperature is 350~650℃, preferably 500~600℃; the calcination time is 4~8h; the calcination is carried out in an air atmosphere.

[0017] Further, the phosphoric acid and / or its acidic salt solution is added dropwise to the Zr-Ce nitrate mixture at a flow rate of 1% to 5% of solution volume / min.

[0018] Furthermore, the stirring speed is 200~800 rpm, preferably 400~600 rpm, and the stirring time is 0.5~2h.

[0019] Furthermore, the settling time is 1 to 5 hours.

[0020] Furthermore, water is used as the washing solution in the washing process.

[0021] Furthermore, the drying temperature is 100~120℃.

[0022] Furthermore, the temperature during stirring and settling is 5~30℃, preferably 5~15℃.

[0023] The second technical solution of the present invention is to provide a phosphate catalyst for the preparation of sandalwood 803, which is prepared by the preparation method described above.

[0024] The third technical solution of the present invention is to provide an application of a phosphate catalyst for the preparation of sandalwood 803, wherein the phosphate catalyst is used to prepare sandalwood 803.

[0025] The fourth technical solution of the present invention provides a continuous production process for the preparation of sandalwood 803, which uses the aforementioned phosphate catalyst for production. The continuous production process includes the following steps:

[0026] The phosphate catalyst is immobilized and then loaded into a fixed-bed reactor, where it is preheated.

[0027] Phenol and camphene were introduced into the fixed-bed reactor for a gas-phase reaction, and after cooling, crude terpene phenol was obtained.

[0028] The crude terpenoid phenol product was separated by distillation to obtain a concentrated terpenoid phenol solution, which was then placed in a high-pressure reactor. Raney nickel was used as a hydrogenation catalyst, and hydrogen gas was introduced to carry out a hydrogenation reaction to obtain sandalwood 803.

[0029] Furthermore, the phosphate catalyst is preheated using a reaction gas at 300~400℃;

[0030] The phosphate catalyst is loaded at a rate of 50% to 80% of the volume of the isothermal section of the fixed-bed reactor.

[0031] Before the phenol and camphene are introduced into the fixed-bed reactor, the pressure in the fixed-bed reactor is 1~4 MPa;

[0032] The molar ratio of phenol to camphene is 1-4:1, and the mass hourly space velocity is adjusted to 1-5 h⁻¹. -1 Adjust the reaction temperature to 300~400℃.

[0033] Furthermore, the reactant gas is nitrogen.

[0034] Furthermore, the preheating time is 0.5 to 2 hours.

[0035] Furthermore, nitrogen gas is introduced into the fixed-bed reactor to make the pressure in the fixed-bed reactor 1~4MPa.

[0036] Furthermore, the mass of the Raney nickel is 1 wt% to 6 wt% of the terpene phenol concentrate;

[0037] The hydrogenation reaction is carried out at a pressure of 3-6 MPa, a temperature of 120-200℃, and a time of 4-10 h.

[0038] Furthermore, the phosphate catalyst is fixed and shaped using a mold.

[0039] Furthermore, the pressure of the hydrogen gas introduced is 1~3 MPa.

[0040] Furthermore, the initial pressure in the high-pressure reactor is 1~3MPa.

[0041] Furthermore, the stirring rate in the high-pressure reactor is 300~600 rpm.

[0042] Compared with the prior art, the present invention has the following advantages:

[0043] (1) The phosphate catalyst prepared in this invention has strong acidity and high catalytic activity. Zirconium phosphate has better selectivity for CC alkylation in the phenol camphene alkylation reaction. Cerium phosphate has a large specific surface area. By adding cerium phosphate, the conversion rate of the reaction is enhanced, the selectivity of meta-alkylation products is improved, and molecular mobility in the catalyst is reduced, thus reducing coking and improving the catalyst lifetime. The prepared phosphate has advantages such as high activity, good stability, and fast reaction rate in the preparation process of sandalwood 803 (alkylation reaction), and its effect is far superior to using conventional clay as a reaction catalyst.

[0044] (2) The continuous production process for sandalwood 803 provided by this invention fully utilizes the advantages of fixed-bed reactors, such as high reaction temperature, continuous reaction, and high-pressure reaction capability. It transforms the phenol camphene alkylation reaction from a batch-type liquid-phase reaction to a fixed-bed high-temperature gas-phase reaction, providing a novel gas-phase alkylation synthesis route for sandalwood 803. During the alkylation reaction, the preparation of meta-reaction products is difficult, with most being ortho- or para-reaction products. Increasing the reaction temperature can improve the yield of meta-reaction products. Furthermore, the conversion rate and CC alkylation selectivity are higher under gas-phase reaction conditions, and the high-pressure reaction also promotes the reaction. This overcomes the shortcomings of traditional batch reactors (intermittency) and the low content of meta-terpene phenols due to low liquid-phase reaction temperatures. It is safer, more environmentally friendly, easier to scale up, and suitable for industrial production. Attached Figure Description

[0045] Figure 1The reaction mechanism of the preparation process of sandalwood 803;

[0046] Figure 2 This refers to the structural isomerism of the camphene group under the action of an acidic catalyst during the alkylation of camphene in phenol. Detailed Implementation

[0047] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. These embodiments are implemented based on the technical solution of the present invention, providing detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following embodiments. All other embodiments obtained by those skilled in the art based on the given embodiments without creative effort are within the scope of protection of this application.

[0048] Unless otherwise specified, the reagents, methods, instruments, and equipment used in this invention are conventional in the art. The experimental reagents and instruments used in the following embodiments are shown in Tables 1 and 2.

[0049] Table 1 Experimental Reagents

[0050]

[0051] Table 2. Instruments used in the experiment

[0052]

[0053] Example 1

[0054] A method for preparing a phosphate catalyst for the preparation of sandalwood 803 includes the following steps:

[0055] (1) Add Zr(NO3)4·5H2O and Ce(NO3)3·6H2O to a beaker at a molar ratio of 4:1, add deionized water, and prepare a 0.1 mol / L Zr-Ce nitrate mixture;

[0056] (2) Dissolve H3PO4 in deionized water and stir until completely dissolved to prepare a 0.1 mol / L H3PO4 solution;

[0057] (3) The H3PO4 solution was introduced into the Zr-Ce nitrate mixture at a rate of 20 mL / min using a peristaltic pump. Ammonia was added to adjust the pH of the solution to 7, and the mixture was stirred at 500 rpm / min for 1 h. After stirring, the mixture was allowed to stand for 2 h to precipitate. During the stirring and standing process, the temperature was controlled at 10 °C using a constant temperature water bath. The molar ratio of H3PO4 required for the precipitation of Zr(NO3)4·5H2O and Ce(NO3)3·6H2O to the actual added H3PO4 was 1:1.2.

[0058] (4) After filtering the precipitated product, the filter cake is repeatedly washed with deionized water and filtered again. This process is repeated 3 times. The resulting filter cake is dried in an oven at 110°C and then calcined in a muffle furnace at 550°C for 4 hours to obtain Ce-Zr(HPO4)2 phosphate catalyst.

[0059] A continuous production process for preparing sandalwood 803, using the aforementioned Ce-Zr(HPO4)2 phosphate catalyst, includes the following steps:

[0060] (1) The Ce-Zr(HPO4)2 phosphate catalyst described in this embodiment was fixed into shape, and 6g was loaded into a fixed bed reactor. Nitrogen gas was continuously introduced (20mL / min) for 30 minutes to remove excess air in the fixed bed. The temperature was increased to the reaction temperature of 380℃ at a programmed rate of 10℃ / min and held for 1h to preheat and activate the Ce-Zr(HPO4)2 phosphate catalyst.

[0061] (2) Maintain the nitrogen temperature and continuously introduce nitrogen until the pressure inside the fixed bed is maintained at 2 MPa. Melt and mix camphene and phenol at a ratio of 1:4, and then pump the solution through a high-pressure pump with a mass hourly space velocity of 1 h⁻¹. -1 The gas-phase alkylation reaction was carried out in a fixed bed. The catalyst and reaction conditions were evaluated for 48 hours, and samples were taken at 12-hour intervals to detect the content of the reaction products.

[0062] (3) After 48 hours of gas-phase alkylation, the collected reaction liquid was distilled to separate the raw materials and obtain a terpene phenol concentrate. A mixture of 3 wt% Raney nickel and terpene phenol was placed in a high-pressure reactor, and hydrogen gas at 2 MPa was repeatedly introduced twice to remove excess air. Hydrogen gas was continuously introduced to maintain a reaction pressure of 4 MPa in the reactor. The reaction temperature was adjusted to 150℃ and the stirring speed of the reactor was adjusted to 400 rpm / min to hydrogenate the terpene phenol to prepare sandalwood 803. The reaction process is as follows: Figure 1 and Figure 2 . Figure 1 This is a process flow diagram for the preparation of sandalwood 803, including the alkylation reaction of phenol and camphene under acidic catalyst and the hydrogenation of the alkylation product via Raney nickel catalysis to prepare sandalwood 803. Figure 2 During the alkylation process, camphene reacts with phenol under the catalysis of an acidic catalyst, and the camphene group undergoes isomerization to form different isomer groups.

[0063] This invention prepares a phosphate catalyst. Phosphate exhibits strong acidity and high catalytic activity. Zirconium phosphate demonstrates better selectivity for CC alkylation in the phenol-camphene alkylation reaction. Cerium phosphate has a large specific surface area; by adding cerium phosphate, the conversion rate of the reaction is enhanced, the selectivity of meta-alkylation products is improved, and molecular mobility in the catalyst is reduced, thus minimizing coking. During the alkylation reaction, the preparation of meta-products is difficult, with ortho- or para-products being the most common. Increasing the reaction temperature can improve the yield of meta-products. Furthermore, the conversion rate and CC alkylation selectivity are higher under gas-phase reaction conditions, and high-pressure reaction also promotes the reaction. This method overcomes the drawbacks of traditional batch reactors, such as intermittent operation and low meta-terpene phenol content due to low liquid-phase reaction temperatures. It is safer, more environmentally friendly, easier to scale up, and suitable for industrial production.

[0064] Example 2

[0065] A method for preparing a phosphate catalyst for the preparation of sandalwood 803 is largely the same as in Example 1, except that the molar ratio of Zr(NO3)4·5H2O and Ce(NO3)3·6H2O is changed from 4:1 to 2:1 to obtain Ce-Zr(HPO4)2 phosphate catalyst.

[0066] A continuous production process for the preparation of sandalwood 803 is the same as that in Example 1, except that the Ce-Zr(HPO4)2 phosphate catalyst is replaced with the Ce-Zr(HPO4)2 phosphate catalyst prepared in this example.

[0067] Example 3

[0068] A method for preparing a phosphate catalyst for the preparation of sandalwood 803 is largely the same as in Example 1, except that the molar ratio of Zr(NO3)4·5H2O and Ce(NO3)3·6H2O is changed from 4:1 to 1:1 to obtain Ce-Zr(HPO4)2 phosphate catalyst.

[0069] A continuous production process for the preparation of sandalwood 803 is the same as that in Example 1, except that the Ce-Zr(HPO4)2 phosphate catalyst is replaced with the Ce-Zr(HPO4)2 phosphate catalyst prepared in this example.

[0070] Example 4

[0071] A method for preparing a phosphate catalyst for the preparation of sandalwood 803 is largely the same as in Example 1, except that the molar ratio of Zr(NO3)4·5H2O and Ce(NO3)3·6H2O is changed from 4:1 to 0.5:1 to obtain Ce-Zr(HPO4)2 phosphate catalyst.

[0072] A continuous production process for the preparation of sandalwood 803 is the same as that in Example 1, except that the Ce-Zr(HPO4)2 phosphate catalyst is replaced with the Ce-Zr(HPO4)2 phosphate catalyst prepared in this example.

[0073] Example 5

[0074] A method for preparing a phosphate catalyst for the preparation of sandalwood 803 is largely the same as in Example 1, except that the molar ratio of Zr(NO3)4·5H2O and Ce(NO3)3·6H2O is changed from 4:1 to 0.25:1 to obtain Ce-Zr(HPO4)2 phosphate catalyst.

[0075] A continuous production process for the preparation of sandalwood 803 is the same as that in Example 1, except that the Ce-Zr(HPO4)2 phosphate catalyst is replaced with the Ce-Zr(HPO4)2 phosphate catalyst prepared in this example.

[0076] Example 6

[0077] A method for preparing a phosphate catalyst for the preparation of sandalwood 803 is largely the same as in Example 1, except that the molar ratio of Zr(NO3)4·5H2O and Ce(NO3)3·6H2O is changed from 4:1 to 0.1:1 to obtain Ce-Zr(HPO4)2 phosphate catalyst.

[0078] A continuous production process for the preparation of sandalwood 803 is the same as that in Example 1, except that the Ce-Zr(HPO4)2 phosphate catalyst is replaced with the Ce-Zr(HPO4)2 phosphate catalyst prepared in this example.

[0079] Example 7

[0080] A method for preparing a phosphate catalyst for the preparation of sandalwood 803 is largely the same as in Example 1, except that H3PO4 is changed to NH4H2PO4 to obtain Ce-Zr(HPO4)2 phosphate catalyst.

[0081] A continuous production process for the preparation of sandalwood 803 is the same as that in Example 1, except that the Ce-Zr(HPO4)2 phosphate catalyst is replaced with the Ce-Zr(HPO4)2 phosphate catalyst prepared in this example.

[0082] Example 8

[0083] A method for preparing a phosphate catalyst for the preparation of sandalwood 803 is largely the same as in Example 1, except that H3PO4 is adjusted to (NH4)2HPO4 to obtain Ce-Zr(HPO4)2 phosphate catalyst.

[0084] A continuous production process for the preparation of sandalwood 803 is the same as that in Example 1, except that the Ce-Zr(HPO4)2 phosphate catalyst is replaced with the Ce-Zr(HPO4)2 phosphate catalyst prepared in this example.

[0085] Example 9

[0086] A method for preparing a phosphate catalyst for the preparation of sandalwood 803 is largely the same as in Example 1, except that ammonia is added to adjust the pH of the solution from 7 to 6, thus obtaining the Ce-Zr(HPO4)2 phosphate catalyst.

[0087] A continuous production process for the preparation of sandalwood 803 is the same as that in Example 1, except that the Ce-Zr(HPO4)2 phosphate catalyst is replaced with the Ce-Zr(HPO4)2 phosphate catalyst prepared in this example.

[0088] Example 10

[0089] A method for preparing a phosphate catalyst for the preparation of sandalwood 803 is largely the same as in Example 1, except that ammonia is added to adjust the pH of the solution from 7 to 8, thus obtaining a Ce-Zr(HPO4)2 phosphate catalyst.

[0090] A continuous production process for the preparation of sandalwood 803 is the same as that in Example 1, except that the Ce-Zr(HPO4)2 phosphate catalyst is replaced with the Ce-Zr(HPO4)2 phosphate catalyst prepared in this example.

[0091] Example 11

[0092] A method for preparing a phosphate catalyst for the preparation of sandalwood 803 is largely the same as in Example 1, except that the temperature control during stirring and standing is changed from 10°C to 5°C, resulting in a Ce-Zr(HPO4)2 phosphate catalyst.

[0093] A continuous production process for the preparation of sandalwood 803 is the same as that in Example 1, except that the Ce-Zr(HPO4)2 phosphate catalyst is replaced with the Ce-Zr(HPO4)2 phosphate catalyst prepared in this example.

[0094] Example 12

[0095] A method for preparing a phosphate catalyst for the preparation of sandalwood 803 is largely the same as in Example 1, except that the temperature control during stirring and standing is changed from 10°C to 20°C, resulting in a Ce-Zr(HPO4)2 phosphate catalyst.

[0096] A continuous production process for the preparation of sandalwood 803 is the same as that in Example 1, except that the Ce-Zr(HPO4)2 phosphate catalyst is replaced with the Ce-Zr(HPO4)2 phosphate catalyst prepared in this example.

[0097] Example 13

[0098] A method for preparing a phosphate catalyst for the preparation of sandalwood 803 is largely the same as in Example 1, except that the temperature control during stirring and standing is changed from 10°C to 30°C, resulting in a Ce-Zr(HPO4)2 phosphate catalyst.

[0099] A continuous production process for the preparation of sandalwood 803 is the same as that in Example 1, except that the Ce-Zr(HPO4)2 phosphate catalyst is replaced with the Ce-Zr(HPO4)2 phosphate catalyst prepared in this example.

[0100] Example 14

[0101] A method for preparing a phosphate catalyst for the preparation of sandalwood 803 is largely the same as in Example 1, except that the calcination temperature in the muffle furnace is changed from 550℃ to 350℃ to obtain a Ce-Zr(HPO4)2 phosphate catalyst.

[0102] A continuous production process for the preparation of sandalwood 803 is the same as that in Example 1, except that the Ce-Zr(HPO4)2 phosphate catalyst is replaced with the Ce-Zr(HPO4)2 phosphate catalyst prepared in this example.

[0103] Example 15

[0104] A method for preparing a phosphate catalyst for the preparation of sandalwood 803 is largely the same as in Example 1, except that the calcination temperature in the muffle furnace is changed from 550℃ to 650℃ to obtain a Ce-Zr(HPO4)2 phosphate catalyst.

[0105] A continuous production process for the preparation of sandalwood 803 is the same as that in Example 1, except that the Ce-Zr(HPO4)2 phosphate catalyst is replaced with the Ce-Zr(HPO4)2 phosphate catalyst prepared in this example.

[0106] Example 16

[0107] A method for preparing a phosphate catalyst for the preparation of sandalwood 803 is the same as in Example 1, yielding a Ce-Zr(HPO4)2 phosphate catalyst.

[0108] A continuous production process for preparing sandalwood 803 is largely the same as in Example 1, except that the reaction temperature is changed from 380°C to 300°C.

[0109] Example 17

[0110] A method for preparing a phosphate catalyst for the preparation of sandalwood 803 is the same as in Example 1, yielding a Ce-Zr(HPO4)2 phosphate catalyst.

[0111] A continuous production process for preparing sandalwood 803 is largely the same as in Example 1, except that the reaction temperature is changed from 380°C to 350°C.

[0112] Example 18

[0113] A method for preparing a phosphate catalyst for the preparation of sandalwood 803 is the same as in Example 1, yielding a Ce-Zr(HPO4)2 phosphate catalyst.

[0114] A continuous production process for preparing sandalwood 803 is largely the same as in Example 1, except that the reaction temperature is changed from 380°C to 400°C.

[0115] Example 19

[0116] A method for preparing a phosphate catalyst for the preparation of sandalwood 803 is the same as in Example 1, yielding a Ce-Zr(HPO4)2 phosphate catalyst.

[0117] A continuous production process for the preparation of sandalwood 803 is largely the same as in Example 1, except that the pressure inside the fixed-bed reactor is changed from 2 MPa to 1 MPa.

[0118] Example 20

[0119] A method for preparing a phosphate catalyst for the preparation of sandalwood 803 is the same as in Example 1, yielding a Ce-Zr(HPO4)2 phosphate catalyst.

[0120] A continuous production process for the preparation of sandalwood 803 is largely the same as in Example 1, except that the pressure inside the fixed-bed reactor is changed from 2 MPa to 3 MPa.

[0121] Example 21

[0122] A method for preparing a phosphate catalyst for the preparation of sandalwood 803 is the same as in Example 1, yielding a Ce-Zr(HPO4)2 phosphate catalyst.

[0123] A continuous production process for preparing sandalwood 803 is largely the same as in Example 1, except that the ratio of camphene to phenol is changed from 1:4 to 1:1.

[0124] Example 22

[0125] A method for preparing a phosphate catalyst for the preparation of sandalwood 803 is the same as in Example 1, yielding a Ce-Zr(HPO4)2 phosphate catalyst.

[0126] A continuous production process for preparing sandalwood 803 is largely the same as in Example 1, except that the ratio of camphene to phenol is changed from 1:4 to 1:2.

[0127] Example 23

[0128] A method for preparing a phosphate catalyst for the preparation of sandalwood 803 is the same as in Example 1, yielding a Ce-Zr(HPO4)2 phosphate catalyst.

[0129] A continuous production process for preparing sandalwood 803 is largely the same as in Example 1, except that the ratio of camphene to phenol is changed from 1:4 to 1:3.

[0130] Example 24

[0131] A method for preparing a phosphate catalyst for the preparation of sandalwood 803 is the same as in Example 1, yielding a Ce-Zr(HPO4)2 phosphate catalyst.

[0132] A continuous production process for preparing sandalwood 803 is largely the same as in Example 1, except that the mass hourly space velocity (MHSV) is increased to 1 h⁻¹. -1 Change to 2h -1 .

[0133] Example 25

[0134] A method for preparing a phosphate catalyst for the preparation of sandalwood 803 is the same as in Example 1, yielding a Ce-Zr(HPO4)2 phosphate catalyst.

[0135] A continuous production process for preparing sandalwood 803 is largely the same as in Example 1, except that the mass hourly space velocity (MHSV) is increased to 1 h⁻¹. -1 Change to 3h -1 .

[0136] Example 26

[0137] A method for preparing a phosphate catalyst for the preparation of sandalwood 803 is the same as in Example 1, yielding a Ce-Zr(HPO4)2 phosphate catalyst.

[0138] A continuous production process for the preparation of sandalwood 803 is largely the same as in Example 1, except that the gas-phase alkylation reaction is changed from 48h to 300h.

[0139] Comparative Example 1

[0140] A method for preparing a phosphate catalyst for the preparation of sandalwood 803 is largely the same as in Example 1, except that the molar ratio of Zr(NO3)4·5H2O and Ce(NO3)3·6H2O is changed from 4:1 to 10:1 to obtain Ce-Zr(HPO4)2 phosphate catalyst.

[0141] A continuous production process for the preparation of sandalwood 803 is the same as that in Example 1, except that the Ce-Zr(HPO4)2 phosphate catalyst is replaced with the Ce-Zr(HPO4)2 phosphate catalyst prepared in this comparative example.

[0142] Comparative Example 2

[0143] A method for preparing a phosphate catalyst for the preparation of sandalwood 803 is largely the same as in Example 1, except that Zr(NO3)4·5H2O and Ce(NO3)3·6H2O are both replaced with Al(NO3)3·9H2O, that is, the amount of H3PO4 added is 1.2 times the theoretical amount, thus obtaining an AlPO4 phosphate catalyst.

[0144] A continuous production process for the preparation of sandalwood 803 is the same as that in Example 1, except that the Ce-Zr(HPO4)2 phosphate catalyst is replaced with the AlPO4 phosphate catalyst prepared in this comparative example.

[0145] Comparative Example 3

[0146] A method for preparing a phosphate catalyst for the preparation of sandalwood 803 is largely the same as in Example 1, except that Zr(NO3)4·5H2O and Ce(NO3)3·6H2O are both replaced with Zr(NO3)4·6H2O, that is, the amount of H3PO4 added is 1.2 times the theoretical amount, to obtain a Zr(HPO4)2 phosphate catalyst.

[0147] A continuous production process for the preparation of sandalwood 803 is the same as that in Example 1, except that the Ce-Zr(HPO4)2 phosphate catalyst is replaced with the Zr(HPO4)2 phosphate catalyst prepared in this comparative example.

[0148] Comparative Example 4

[0149] A method for preparing a phosphate catalyst for the preparation of sandalwood 803 is largely the same as in Example 1, except that Zr(NO3)4·5H2O and Ce(NO3)3·6H2O are both replaced with Zn(NO3)2·6H2O, that is, the amount of H3PO4 added is 1.2 times the theoretical amount, to obtain Zn3(PO4)2 phosphate catalyst.

[0150] A continuous production process for the preparation of sandalwood 803 is the same as that in Example 1, except that the Ce-Zr(HPO4)2 phosphate catalyst is replaced with the Zn3(PO4)2 phosphate catalyst prepared in this comparative example.

[0151] Comparative Example 5

[0152] A method for preparing a phosphate catalyst for the preparation of sandalwood 803 is largely the same as in Example 1, except that Zr(NO3)4·5H2O and Ce(NO3)3·6H2O are both replaced with La(NO3)3·6H2O, that is, the amount of H3PO4 added is 1.2 times the theoretical amount, thus obtaining a LaPO4 phosphate catalyst.

[0153] A continuous production process for the preparation of sandalwood 803 is the same as that in Example 1, except that the Ce-Zr(HPO4)2 phosphate catalyst is replaced with the LaPO4 phosphate catalyst prepared in this comparative example.

[0154] Comparative Example 6

[0155] A method for preparing a phosphate catalyst for the preparation of sandalwood 803 is largely the same as in Example 1, except that Zr(NO3)4·5H2O and Ce(NO3)3·6H2O are both replaced with Mg(NO3)2·6H2O, that is, the amount of H3PO4 added is 1.2 times the theoretical amount, to obtain Mg3(PO4)2 phosphate catalyst.

[0156] A continuous production process for the preparation of sandalwood 803 is the same as that in Example 1, except that the Ce-Zr(HPO4)2 phosphate catalyst is replaced with the Mg3(PO4)2 phosphate catalyst prepared in this comparative example.

[0157] Comparative Example 7

[0158] A method for preparing a phosphate catalyst for the preparation of sandalwood 803 is largely the same as in Example 1, except that Zr(NO3)4·5H2O and Ce(NO3)3·6H2O are both replaced with Ce(NO3)3·6H2O, that is, the amount of H3PO4 added is 1.2 times the theoretical amount, thus obtaining a CePO4 phosphate catalyst.

[0159] A continuous production process for the preparation of sandalwood 803 is the same as that in Example 1, except that the Ce-Zr(HPO4)2 phosphate catalyst is replaced with the CePO4 phosphate catalyst prepared in this comparative example.

[0160] Comparative Example 8

[0161] A method for preparing a phosphate catalyst for the preparation of sandalwood 803 is largely the same as in Example 1, except that Ce(NO3)3·6H2O is replaced with Al(NO3)3·9H2O, and the amount of H3PO4 added is 1.2 times the theoretical amount, resulting in an Al-Zr(HPO4)2 phosphate catalyst.

[0162] A continuous production process for the preparation of sandalwood 803 is the same as that in Example 1, except that the Ce-Zr(HPO4)2 phosphate catalyst is replaced with the Al-Zr(HPO4)2 phosphate catalyst prepared in this comparative example.

[0163] Comparative Example 9

[0164] A method for preparing a phosphate catalyst for the preparation of sandalwood 803 is largely the same as in Example 1, except that Ce(NO3)3·6H2O is replaced with Zn(NO3)2·6H2O, and the amount of H3PO4 added is 1.2 times the theoretical amount, resulting in a Zn-Zr(HPO4)2 phosphate catalyst.

[0165] A continuous production process for the preparation of sandalwood 803 is the same as that in Example 1, except that the Ce-Zr(HPO4)2 phosphate catalyst is replaced with the Zn-Zr(HPO4)2 phosphate catalyst prepared in this comparative example.

[0166] Comparative Example 10

[0167] A method for preparing a phosphate catalyst for the preparation of sandalwood 803 is largely the same as in Example 1, except that Ce(NO3)3·6H2O is replaced with Mg(NO3)2·6H2O, i.e., the amount of H3PO4 added is 1.2 times the theoretical amount, resulting in a Mg-Zr(HPO4)2 phosphate catalyst.

[0168] A continuous production process for the preparation of sandalwood 803 is the same as that in Example 1, except that the Ce-Zr(HPO4)2 phosphate catalyst is replaced with the Mg-Zr(HPO4)2 phosphate catalyst prepared in this comparative example.

[0169] Comparative Example 11

[0170] A method for preparing a phosphate catalyst for the preparation of sandalwood 803 is largely the same as in Example 1, except that Ce(NO3)3·6H2O is replaced with La(NO3)3·6H2O, i.e., the amount of H3PO4 added is 1.2 times the theoretical amount, resulting in a La-Zr(HPO4)2 phosphate catalyst.

[0171] A continuous production process for the preparation of sandalwood 803 is the same as that in Example 1, except that the Ce-Zr(HPO4)2 phosphate catalyst is replaced with the La-Zr(HPO4)2 phosphate catalyst prepared in this comparative example.

[0172] The average value of the product results obtained from the gas-phase alkylation reactions of Examples 1-26 and Comparative Examples 1-11 is shown in Table 3 below, along with the content, conversion rate, and selectivity of each component:

[0173] Table 3. Content, conversion rate, and selectivity of each component in the gas-phase alkylation reaction of Examples 1-26 and Comparative Examples 1-11

[0174]

[0175] Table 1 shows the camphene conversion, CO alkylation selectivity, CC alkylation selectivity, and meta-terpene phenol selectivity of the fixed-bed gas-phase alkylation of phenol camphene in Examples 1-26 and Comparative Examples 1-11. The camphene conversion, CC alkylation selectivity, and meta-terpene phenol selectivity obtained under the Ce-Zr(HPO4)2 phosphate catalyst and fixed-bed reaction conditions prepared in Examples 1-26 are all superior to those in Comparative Examples 1-11. Among them, the camphene conversion, CC alkylation selectivity, and meta-terpene phenol selectivity obtained under the Ce-Zr(HPO4)2 phosphate catalyst prepared in Example 1 and the fixed-bed reaction conditions are the highest, and the prepared catalyst exhibits good stability. Furthermore, Example 26 shows that the Ce-Zr(HPO4)2 phosphate catalyst retains its activity after 300 h of reaction, and the camphene conversion, CC alkylation selectivity, and meta-terpene phenol selectivity do not decrease.

[0176] Although the present invention has been described in detail above with general descriptions, specific embodiments, and experiments, modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, all such modifications or improvements made without departing from the spirit of the present invention fall within the scope of protection claimed by the present invention.

Claims

1. A continuous production process for preparing sandalwood 803, characterized in that, The production process, which uses a phosphate catalyst and is a continuous production process, includes the following steps: The phosphate catalyst is immobilized and then loaded into a fixed-bed reactor, where it is preheated. Phenol and camphene were introduced into the fixed-bed reactor for a gas-phase reaction, and after cooling, crude terpene phenol was obtained. The crude terpene phenol product was separated by distillation to obtain a concentrated terpene phenol solution, which was then placed in a high-pressure reactor. Raney nickel was used as a hydrogenation catalyst, and hydrogen was introduced to carry out a hydrogenation reaction to obtain sandalwood 803. The preparation method of the phosphate catalyst includes the following steps: Zr(NO3)4·5H2O and Ce(NO3)3·6H2O were dissolved in water to prepare a Zr-Ce nitrate mixture, wherein the molar ratio of Zr(NO3)4·5H2O to Ce(NO3)3·6H2O was 0.1~8:1, and the concentration of Zr(NO3)4·5H2O in the Zr-Ce nitrate mixture was 0.01~1mol / L. Dissolve phosphoric acid and / or its acid salts in water to obtain a solution of phosphoric acid and / or its acid salts; The phosphoric acid and / or its acidic salt solution were added to the Zr-Ce nitrate mixture, the pH was adjusted, the mixture was stirred and allowed to stand to precipitate, then filtered, washed, dried and calcined to obtain the Ce-Zr(HPO4)2 phosphate catalyst, and the reaction was completed.

2. The continuous production process for preparing sandalwood 803 according to claim 1, characterized in that, The phosphoric acid and / or its acid salts include one or more of H3PO4, NH4H2PO4, and (NH4)2HPO4; The concentration of the phosphoric acid and / or its acidic salt solution is 0.01~1 mol / L.

3. The continuous production process for preparing sandalwood 803 according to claim 1, characterized in that, The actual amount of phosphoric acid and / or its acid salt added is 0.75 to 1.25 times the theoretical molar amount of phosphoric acid and / or its acid salt required for the complete precipitation of Zr(NO3)4·5H2O and Ce(NO3)3·6H2O.

4. The continuous production process for preparing sandalwood 803 according to claim 1, characterized in that, During pH adjustment, ammonia water is used to adjust the pH to 6-8; The calcination temperature is 350~650℃.

5. The continuous production process for preparing sandalwood 803 according to claim 1, characterized in that, The phosphate catalyst was preheated using a reaction gas at 300-400℃; The phosphate catalyst is loaded at a rate of 50% to 80% of the volume of the isothermal section of the fixed-bed reactor. Before the phenol and camphene are introduced into the fixed-bed reactor, the pressure in the fixed-bed reactor is 1~4 MPa; The molar ratio of phenol to camphene is 1-4:1, and the mass hourly space velocity is adjusted to 1-5 h⁻¹. -1 Adjust the reaction temperature to 300~400℃.

6. The continuous production process for preparing sandalwood 803 according to claim 1, characterized in that, The Raney nickel is present in an amount of 1 wt% to 6 wt% of the terpene phenol concentrate. The hydrogenation reaction is carried out at a pressure of 3-6 MPa and a temperature of 120-200℃.

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