Preparation method of light-color C9 petroleum resin

Abstract

The invention relates to the technical field of C9 petroleum resins, and particularly discloses a preparation method of a light-color C9 petroleum resin, which comprises the following steps: pretreating an ethylene cracking byproduct C9 fraction, introducing the pretreated raw material into an adsorption bed filled with an adsorbent, carrying out impurity removal treatment, removing impurities, and drying to obtain the light-color C9 petroleum resin. Mixing the pretreated raw material, a diluent and a catalyst to react to obtain a polymerization product, uniformly mixing the polymerization product with cyclohexane, activating a hydrogenation catalyst, stirring and mixing, carrying out hydrogenation reaction, and rectifying after the reaction is finished to obtain the light-color C9 petroleum resin. According to the light-color C9 petroleum resin, the C9 fraction is subjected to pretreatment, adsorption impurity removal, concerted catalytic polymerization and hydrogenation modification, green and high-performance production of the light-color C9 petroleum resin is achieved, and the light-color C9 petroleum resin has excellent weather resistance and thermal stability, is low in chromaticity and is suitable for the high-end fields of food packaging adhesives, medical catheter coatings and the like.

Description

Technical Field

[0001] The invention relates to the technical field of carbon nine petroleum resins, in particular to a preparation method of light-colored carbon nine petroleum resins. Background Art

[0002] C9 petroleum resin is an important synthetic resin. It uses the C9 fraction, a byproduct of ethylene cracking, as its primary raw material. It is a solid or viscous liquid low-molecular-weight polymer produced through polymerization. It features low acidity, good miscibility, a low melting point, and strong adhesion. C9 petroleum resin is widely used in adhesives, coatings, rubber additives, and other fields. However, conventional C9 petroleum resins have complex components, and the preparation process presents challenges such as difficult to control the resin's color, dark color, and poor thermal stability, limiting their application in high-end applications.

[0003] The color of C9 petroleum resin primarily originates from sulfur-nitrogen heterocyclic compounds, conjugated diene polymerization products, and residual metal ions in the raw materials. In recent years, with the increasing demand for light-colored resins in various applications, the industry has developed a variety of improved processes. Chinese patent application CN102757530A discloses a method for preparing a light-colored cold-polymerized C9 petroleum resin. The method involves extracting Fraction A with a boiling point of 150-190°C from the C9 fraction, a byproduct of ethylene cracking. Fraction B is then depolymerized at atmospheric pressure to remove most dimers. Fraction B is then prepolymerized at ambient temperature using a Friedel-Crafts catalyst to obtain Fraction C. Fraction C is then polymerized with a solvent and a boron trifluoride ether catalyst, followed by catalyst removal and solvent removal by vacuum distillation to obtain the C9 petroleum resin. This C9 petroleum resin preparation method features a simple process, mild reaction conditions, and compatibility with C9 fractions of varying compositions, making it suitable for industrial production. The resulting C9 petroleum resin exhibits light hue and good compatibility, but the washing process produces a large amount of fluorine-containing wastewater and results in a low yield. Chinese patent application CN101659733A discloses a method for synthesizing a light-colored C9 petroleum resin. The method uses refined C9 with a boiling range of 80-190°C from the C9 fraction, a byproduct of ethylene cracking, as the raw material. After solvent extraction, sedimentation separation, and water washing to neutrality, the resin is thermally polymerized at a temperature range of 210-280°C and a pressure of 0.5-2.0 MPa. Unreacted monomers and oligomers are then removed. This synthesis method requires no catalyst, no post-catalyst removal treatment, and no waste residue or fluorine-containing waste alkali water. However, the reaction time is long, energy consumption is high, and it is prone to local overheating, which can darken the resin color and affect softening point stability.

[0004] Therefore, it is of great significance to provide a carbon nine petroleum resin with light color and excellent performance. Summary of the Invention

[0005] (1) The technical problems to be solved will be In view of the shortcomings of the existing technology, the present invention provides a method for preparing a light-colored carbon nine petroleum resin, which solves the problem of dark color of carbon nine petroleum resin and can be widely used in the field of high-end technology.

[0006] (2) Technical solution In order to achieve the above object, the present invention discloses a method for preparing a light-colored carbon nine petroleum resin, comprising the following steps: The C9 fraction, a by-product of ethylene cracking, is pretreated. The pretreated raw material is passed through an adsorption bed containing an adsorbent for impurity removal. After impurities are removed, the pretreated raw material, diluent, and catalyst are mixed and reacted to obtain a polymer product. The polymer product is uniformly mixed with cyclohexane. After the hydrogenation catalyst is activated, the mixture is stirred and mixed, and a hydrogenation reaction is carried out. After the reaction is completed, the mixture is distilled to obtain a light-colored C9 petroleum resin. The adsorbent is a maleic anhydride modified TiO2 / biochar composite adsorbent; The hydrogenation catalyst is a Ni / Al2O3 / TiO2 catalyst.

[0007] Preferably, the preparation method of the light-colored carbon nine petroleum resin comprises the following specific steps: Step 1: distilling the ethylene cracking by-product C9 fraction under reduced pressure in a vacuum distillation tower at a vacuum degree of -0.092 MPa to -0.098 MPa, intercepting the fraction with a boiling point of 125°C to 155°C to obtain a pretreated raw material; Step 2: The pre-treated raw material is subjected to impurity removal treatment, and the pre-treated raw material is passed into an adsorption bed filled with an adsorbent to remove impurities; Step 3: adding the pretreated raw material from which impurities have been removed and the diluent to the reactor, stirring and mixing uniformly, slowly adding the catalyst in a nitrogen atmosphere to react, adding a 5 wt % aqueous sodium carbonate solution to terminate the reaction, and after the reaction is completed, centrifuging and separating, taking the supernatant and performing vacuum distillation at a vacuum distillation temperature of 200-240° C. and a vacuum degree of -0.095 MPa to obtain a polymer product; Step 4: Activate the hydrogenation catalyst, mix the polymerization product with cyclohexane evenly, add them to the reactor, introduce hydrogen into the reactor, adjust the pressure of the reactor to 4-5 MPa, add the activated hydrogenation catalyst, stir and mix, and carry out hydrogenation reaction. After the reaction is completed, separate the product, take liquid phase distillation, and obtain light-colored carbon nine petroleum resin.

[0008] Furthermore, the amount of the adsorbent used in step 2 is 1%-5% of the mass of the pretreated raw material.

[0009] Preferably, the preparation method of the maleic anhydride-modified TiO2 / biochar composite adsorbent in step 2 comprises the following steps: A1. Add deionized water and titanium tetrachloride to reactor A, disperse evenly by ultrasonication, then add biochar, heat and stir to react, adjust the pH to neutral, wash with deionized water, and dry to obtain TiO2 / biochar; A2. Add methanol and TiO2 / biochar to reactor B, disperse them uniformly by ultrasonication, then add γ-aminopropyltriethoxysilane, stir and mix, and react. After the reaction is complete, filter, wash with anhydrous ethanol and deionized water, and dry to obtain amination-treated TiO2 / biochar. A3. Add dimethyl sulfoxide and amino TiO2 / biochar to reactor C, and after ultrasonic dispersion, add maleic anhydride, dicyclohexylcarbodiimide and 4-dimethylaminopyridine, stir and mix, and react. After the reaction is completed, filter, wash with ethyl acetate and deionized water, and dry to obtain a maleic anhydride-modified TiO2 / biochar composite adsorbent.

[0010] Preferably, the mass ratio of deionized water, titanium tetrachloride and biochar in A1 is 3800-4500:75-120:100.

[0011] Preferably, the reaction temperature in A1 is 65-95° C., and the reaction time is 4-8 h.

[0012] Preferably, the mass ratio of methanol, TiO2 / biochar, and γ-aminopropyltriethoxysilane in A2 is 2000-2400:100:18-25.

[0013] Preferably, the reaction temperature in A2 is 55-65° C., and the reaction time is 5-7 h.

[0014] Preferably, the mass ratio of dimethyl sulfoxide, amination TiO2 / biochar, maleic anhydride, dicyclohexylcarbodiimide and 4-dimethylaminopyridine in A3 is 1200-1500:100:50-80:30-42:8-15.

[0015] Preferably, the reaction temperature in A3 is 25-35° C., and the reaction time is 3-5 h.

[0016] Preferably, the mass ratio of the pretreated raw material for removing impurities, the diluent, and the catalyst in step 3 is 100:10-18:0.6-1.5.

[0017] Preferably, the reaction temperature in step 3 is 0-35° C., and the reaction time is 3-5 h.

[0018] Preferably, the diluent in step three is toluene.

[0019] Preferably, the catalyst in step 3 is a composite catalyst, which is composed of ZSM-5 molecular sieve and organic sulfonic acid in a mass ratio of 1:0.1-0.5.

[0020] Furthermore, in the step three, the silicon-aluminum molar ratio of the ZSM-5 molecular sieve is 40-50:1.

[0021] Furthermore, the organic sulfonic acid in step 3 is one of p-toluenesulfonic acid or methanesulfonic acid.

[0022] Preferably, in step 4, the mass ratio of the polymer product, cyclohexane, and the activated hydrogenation catalyst is 100:900-1000:7-10.

[0023] Preferably, during the hydrogenation reaction in step 4, hydrogen is added every 20 minutes to maintain the pressure in the reactor at 4-5 MPa, the reaction temperature at 225-235° C., the reaction time at 2 hours, and the rotation speed at 500 r / min.

[0024] Preferably, the activation treatment conditions in step 4 are as follows: the hydrogenation catalyst is activated at 200° C. and 0.5 MPa hydrogen pressure for 2 h.

[0025] Preferably, the preparation method of the hydrogenation catalyst Ni / Al2O3 / TiO2 catalyst in step 4 comprises the following steps: Nickel nitrate, aluminum nitrate, and deionized water were mixed evenly and stirred until completely dissolved, titanium dioxide was added, ultrasonically dispersed for 30 minutes, 25wt% ammonia water was added to adjust the pH to 8-8.5, stirred and mixed, and reacted. After the reaction was completed, deionized water and anhydrous ethanol were used for washing, centrifugation, drying, and calcination in a muffle furnace to obtain a Ni / Al2O3 / TiO2 catalyst.

[0026] Preferably, the mass ratio of deionized water, nickel nitrate, aluminum nitrate and titanium dioxide in the preparation process of the hydrogenation catalyst Ni / Al2O3 / TiO2 is 900-1200:48-52:34-38:100.

[0027] Preferably, the reaction temperature during the preparation of the hydrogenation catalyst Ni / Al2O3 / TiO2 is 75-85°C and the reaction time is 2-3h.

[0028] Furthermore, during the preparation process of the hydrogenation catalyst Ni / Al2O3 / TiO2, the heating rate of the calcination is 1-3°C / min, the calcination temperature is 600-620°C, and the calcination time is 4h.

[0029] (3) Beneficial technical effects Compared with the prior art, the present invention has the following beneficial effects: (1) The C9 fraction in the present invention is the main raw material for producing C9 petroleum resin. The impurity content of C9 fractions from different sources varies greatly. After pre-treating the C9 fraction, a by-product of ethylene cracking, the heavy and light component impurities can be removed, further inhibiting the gasification of heavy component asphaltene, reducing the possibility of its mixing into the target fraction. In addition, for easily oxidized conjugated polyene impurities, distilling at a lower temperature can greatly reduce the risk of high-temperature oxidation affecting the purity of the C9 fraction, thereby providing a purer raw material for the subsequent preparation of C9 petroleum resin with lighter color and better performance. By reducing the boiling point of the C9 fraction, the separation of the distillation sections is achieved, the heavy component polycyclic aromatic hydrocarbons are removed, the main color bodies are removed from the source, the initial color of the resin is reduced, and the double bond polymerization or carbonization caused by high temperature is avoided. High-purity raw materials can reduce the interference of impurities on the polymerization reaction, thereby improving the stability and durability of the resin.

[0030] (2) Titanium tetrachloride is used as a titanium source in the adsorbent of the present invention. TiO2 / biochar is prepared by a hydrolysis-crystallization method under the induction of biochar, which effectively avoids the agglomeration of titanium dioxide. The porous structure of biochar can intercept macromolecular impurities and effectively adsorb thiophene sulfides in the pretreated raw materials. TiO2 nanoparticles can fill the pores, forming multi-level channels, and improving the adsorption capacity. After modification with maleic anhydride, the introduced carboxyl group can chelate with metal ions, inhibiting their catalytic oxidation and color development, and undergoing a ring-opening reaction with nitrogen-containing heterocycles to generate water-soluble derivatives. Furthermore, the introduced double bond undergoes π-π stacking with the unsaturated polymer. The maleic anhydride-modified TiO2 / biochar composite adsorbent effectively removes metal ions and sulfides.

[0031] (3) The high silicon-aluminum ratio micropores of the ZSM-5 in the present invention can screen out macromolecular pigments, and the organic sulfonic acid enhances the acidic environment, compensating for the insufficient activity of the high silicon-aluminum ratio molecular sieve. Polymerization under low temperature conditions inhibits free radical side reactions, limits the generation of macromolecular byproducts, inhibits the generation of chromophores, and improves the thermal stability of the resin. The addition of toluene as a diluent can effectively reduce the viscosity of the system, promote mass transfer, and avoid resin discoloration caused by local overheating. At the same time, the traditional alkaline washing step is eliminated, reducing fluorine-containing wastewater.

[0032] (4) In the present invention, Ni / Al2O3 / TiO2 catalyst is used as a hydrogenation catalyst. Al2O3 provides a high specific surface area and disperses Ni particles, while TiO2 enhances sintering resistance and maintains high-temperature activity. Ni is used as the main active center to catalyze the dissociation of hydrogen into hydrogen atoms and react with the double bonds of the resin to form an addition reaction. During the hydrogenation reaction, the unsaturated bonds can be saturated, decolorization and cracking can be balanced, and the weather resistance and thermal stability of the matrix can be significantly improved. By pre-treating the C9 fraction, adsorption and decontamination, synergistic catalytic polymerization, and hydrogenation modification, the green and high-performance production of light-colored carbon nine petroleum resin is achieved. It has excellent weather resistance and thermal stability, low chroma, and is suitable for high-end fields such as food packaging adhesives and medical catheter coatings. DETAILED DESCRIPTION

[0033] To facilitate understanding of the present invention, the present invention will be described in more detail below. Preferred embodiments of the present invention are provided below. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and comprehensive understanding of the disclosure of the present invention. Example

[0034] A method for preparing a maleic anhydride-modified TiO2 / biochar composite adsorbent comprises the following steps: A1. Add deionized water and titanium tetrachloride to reactor A. After ultrasonic dispersion, add biochar. The mass ratio of deionized water, titanium tetrachloride, and biochar is 3800:75:100. Heat and stir at 65°C for 8 hours. Adjust the pH to neutral. After the reaction, wash with deionized water and dry to obtain TiO2 / biochar. A2. Methanol and TiO2 / biochar were added to reactor B. After ultrasonic dispersion, γ-aminopropyltriethoxysilane was added. The mass ratio of methanol, TiO2 / biochar, and γ-aminopropyltriethoxysilane was 2000:100:18. The mixture was stirred and reacted at 55°C for 7h. After the reaction, the mixture was filtered, washed with anhydrous ethanol and deionized water, and dried to obtain amination-treated TiO2 / biochar. A3. Add dimethyl sulfoxide and amination TiO2 / biochar to reactor C, and after ultrasonic dispersion, add maleic anhydride, dicyclohexylcarbodiimide and 4-dimethylaminopyridine, wherein the mass ratio of dimethyl sulfoxide, amination TiO2 / biochar, maleic anhydride, dicyclohexylcarbodiimide and 4-dimethylaminopyridine is 1200:100:50:30:8. Stir and mix, react at 25°C for 5h. After the reaction, filter, wash with ethyl acetate and deionized water, and dry to obtain a maleic anhydride-modified TiO2 / biochar composite adsorbent. Example

[0035] A method for preparing a maleic anhydride-modified TiO2 / biochar composite adsorbent comprises the following steps: A1. Add deionized water and titanium tetrachloride to reactor A. After ultrasonic dispersion, add biochar. The mass ratio of deionized water, titanium tetrachloride, and biochar is 4200:105:100. Heat and stir at 85°C for 6 hours. Adjust the pH to neutral. After the reaction, wash with deionized water and dry to obtain TiO2 / biochar. A2. Methanol and TiO2 / biochar were added to reactor B. After ultrasonic dispersion, γ-aminopropyltriethoxysilane was added. The mass ratio of methanol, TiO2 / biochar, and γ-aminopropyltriethoxysilane was 2200:100:22. The mixture was stirred and reacted at 60°C for 6 hours. After the reaction, the mixture was filtered, washed with anhydrous ethanol and deionized water, and dried to obtain amination-treated TiO2 / biochar. A3. Add dimethyl sulfoxide and amination TiO2 / biochar to reactor C, ultrasonically disperse them uniformly, then add maleic anhydride, dicyclohexylcarbodiimide and 4-dimethylaminopyridine, wherein the mass ratio of dimethyl sulfoxide, amination TiO2 / biochar, maleic anhydride, dicyclohexylcarbodiimide and 4-dimethylaminopyridine is 1400:100:70:38:12. Stir and mix, react at 30°C for 4h. After the reaction, filter, wash with ethyl acetate and deionized water, and dry to obtain a maleic anhydride-modified TiO2 / biochar composite adsorbent. Example

[0036] A method for preparing a maleic anhydride-modified TiO2 / biochar composite adsorbent comprises the following steps: A1. Add deionized water and titanium tetrachloride to reactor A. After ultrasonic dispersion, add biochar. The mass ratio of deionized water, titanium tetrachloride, and biochar is 4500:120:100. Heat and stir, react at 95°C for 4 hours, adjust the pH to neutral, and after the reaction, wash with deionized water and dry to obtain TiO2 / biochar. A2. Methanol and TiO2 / biochar were added to reactor B. After ultrasonic dispersion, γ-aminopropyltriethoxysilane was added. The mass ratio of methanol, TiO2 / biochar, and γ-aminopropyltriethoxysilane was 2400:100:25. The mixture was stirred and mixed. The mixture was reacted at 65°C for 5 h. After the reaction, the mixture was filtered, washed with anhydrous ethanol and deionized water, and dried to obtain amination-treated TiO2 / biochar. A3. Add dimethyl sulfoxide and amination TiO2 / biochar to reactor C, ultrasonically disperse them uniformly, then add maleic anhydride, dicyclohexylcarbodiimide and 4-dimethylaminopyridine, wherein the mass ratio of dimethyl sulfoxide, amination TiO2 / biochar, maleic anhydride, dicyclohexylcarbodiimide and 4-dimethylaminopyridine is 1500:100:80:42:15. Stir and mix, react at 35°C for 3h. After the reaction, filter, wash with ethyl acetate and deionized water, and dry to obtain a maleic anhydride-modified TiO2 / biochar composite adsorbent. Example

[0037] A method for preparing a Ni / Al2O3 / TiO2 catalyst comprises the following steps: Nickel nitrate, aluminum nitrate and deionized water were mixed evenly and stirred until completely dissolved, titanium dioxide was added, wherein the mass ratio of deionized water, nickel nitrate, aluminum nitrate and titanium dioxide was 900:48:34:100, ultrasonic dispersion was performed for 30 minutes, 25wt% ammonia water was added to adjust the pH to 8, stirred and mixed, and reacted at 75°C for 3 hours. After the reaction, the mixture was washed with deionized water and anhydrous ethanol, centrifuged, dried, and calcined in a muffle furnace at a heating rate of 1°C / min, a calcination temperature of 600°C, and a calcination time of 4 hours to obtain a Ni / Al2O3 / TiO2 catalyst. Example

[0038] A method for preparing a Ni / Al2O3 / TiO2 catalyst comprises the following steps: Nickel nitrate, aluminum nitrate and deionized water were mixed evenly and stirred until completely dissolved, titanium dioxide was added, wherein the mass ratio of deionized water, nickel nitrate, aluminum nitrate and titanium dioxide was 1100:50:36:100, ultrasonic dispersion was performed for 30 minutes, 25wt% ammonia water was added to adjust the pH to 8.2, stirred and mixed, and reacted at 80°C for 2.5 hours. After the reaction was completed, the mixture was washed with deionized water and anhydrous ethanol, centrifuged, dried, and calcined in a muffle furnace at a heating rate of 2°C / min, a calcination temperature of 610°C, and a calcination time of 4 hours to obtain a Ni / Al2O3 / TiO2 catalyst. Example

[0039] A method for preparing a Ni / Al2O3 / TiO2 catalyst comprises the following steps: Nickel nitrate, aluminum nitrate and deionized water were mixed evenly and stirred until completely dissolved, titanium dioxide was added, wherein the mass ratio of deionized water, nickel nitrate, aluminum nitrate and titanium dioxide was 1200:52:38:100, ultrasonic dispersion was performed for 30 minutes, 25wt% ammonia water was added to adjust the pH to 8.5, stirred and mixed, and reacted at 85°C for 2 hours. After the reaction, deionized water and anhydrous ethanol were used for washing, centrifugation, drying, and calcination in a muffle furnace at a heating rate of 3°C / min, a calcination temperature of 620°C, and a calcination time of 4 hours to obtain a Ni / Al2O3 / TiO2 catalyst. Example

[0040] A method for preparing a light-colored carbon nine petroleum resin comprises the following steps: Step 1: distill the C9 fraction, a by-product of ethylene cracking, under reduced pressure in a vacuum distillation tower at a vacuum degree of -0.092 MPa, and intercept the fraction with a boiling point of 155° C. to obtain a pretreated raw material; Step 2: The pre-treated raw material is subjected to impurity removal treatment. The pre-treated raw material is passed into an adsorption bed filled with an adsorbent. The amount of the adsorbent is 1% of the mass of the pre-treated raw material to remove impurities. Step 3, the pretreated raw material for removing impurities and the diluent toluene are added to the reactor, stirred and mixed evenly, and the catalyst is slowly added in a nitrogen atmosphere. The mass ratio of the pretreated raw material for removing impurities, the diluent toluene, and the catalyst is 100:10:0.6. The catalyst is a composite catalyst, and the composite catalyst is composed of a ZSM-5 molecular sieve and p-toluenesulfonic acid with a mass ratio of 1:0.1, wherein the silicon-aluminum molar ratio of the ZSM-5 molecular sieve is 40:1. The reaction is carried out at 0°C for 5h, and a 5wt% aqueous sodium carbonate solution is added to terminate the reaction. After the reaction is completed, the mixture is centrifuged and the supernatant is subjected to reduced pressure distillation. The reduced pressure distillation temperature is 200°C and the vacuum degree is -0.095MPa. After reduced pressure distillation, a polymer product is obtained; Step 4: Activate the hydrogenation catalyst, activate the hydrogenation catalyst at 200°C and 0.5MPa hydrogen pressure for 2h, mix the polymerization product and cyclohexane evenly, add them to the reactor, introduce hydrogen into the reactor, adjust the pressure of the reactor to 4MPa, add the activated hydrogenation catalyst, wherein the mass ratio of the polymerization product, cyclohexane and the activated hydrogenation catalyst is 100:900:7, stir and mix, and carry out hydrogenation reaction. During the hydrogenation reaction, add hydrogen every 20min, maintain the pressure in the reactor at 4MPa, the reaction temperature at 225°C, the reaction time at 2h, and the rotation speed at 500r / min. After the reaction is completed, separate the product, take the liquid phase for distillation, and obtain a light-colored carbon nine petroleum resin.

[0041] The adsorbent used was the maleic anhydride-modified TiO2 / biochar composite adsorbent prepared in Example 2, and the hydrogenation catalyst used was the Ni / Al2O3 / TiO2 catalyst prepared in Example 5. Example

[0042] A method for preparing a light-colored carbon nine petroleum resin comprises the following steps: Step 1: distill the C9 fraction, a by-product of ethylene cracking, under reduced pressure in a vacuum distillation tower at a vacuum degree of -0.095 MPa, and intercept the fraction with a boiling point of 150° C. to obtain a pretreated raw material; Step 2: The pretreated raw material is subjected to impurity removal treatment. The pretreated raw material is passed into an adsorption bed filled with an adsorbent. The amount of the adsorbent is 4% of the mass of the pretreated raw material to remove impurities. Step 3, the pretreated raw material for removing impurities and the diluent toluene are added to the reactor, stirred and mixed evenly, and the catalyst is slowly added in a nitrogen atmosphere. The mass ratio of the pretreated raw material for removing impurities, the diluent toluene, and the catalyst is 100:15:1.2. The catalyst is a composite catalyst, and the composite catalyst is composed of a ZSM-5 molecular sieve and p-toluenesulfonic acid with a mass ratio of 1:0.4, wherein the silicon-aluminum molar ratio of the ZSM-5 molecular sieve is 45:1. The reaction is carried out at 30°C for 4h, and a 5wt% aqueous sodium carbonate solution is added to terminate the reaction. After the reaction is completed, the reaction is centrifuged and the supernatant is subjected to reduced pressure distillation. The reduced pressure distillation temperature is 220°C and the vacuum degree is -0.095MPa. After reduced pressure distillation, a polymer product is obtained; Step 4: Activate the hydrogenation catalyst, activate the hydrogenation catalyst at 200°C and 0.5MPa hydrogen pressure for 2h, mix the polymerization product and cyclohexane evenly, add them to the reactor, introduce hydrogen into the reactor, adjust the pressure of the reactor to 4.5MPa, add the activated hydrogenation catalyst, wherein the mass ratio of the polymerization product, cyclohexane and the activated hydrogenation catalyst is 100:950:8, stir and mix, and carry out hydrogenation reaction. During the hydrogenation reaction, add hydrogen every 20min, maintain the pressure in the reactor at 4.5MPa, the reaction temperature is 230°C, the reaction time is 2h, and the rotation speed is 500r / min. After the reaction is completed, separate the product, take the liquid phase for distillation, and obtain a light-colored carbon nine petroleum resin.

[0043] The adsorbent used was the maleic anhydride-modified TiO2 / biochar composite adsorbent prepared in Example 2, and the hydrogenation catalyst used was the Ni / Al2O3 / TiO2 catalyst prepared in Example 5. Example

[0044] A method for preparing a light-colored carbon nine petroleum resin comprises the following steps: Step 1: distill the C9 fraction, a by-product of ethylene cracking, under reduced pressure in a vacuum distillation tower at a vacuum degree of -0.098 MPa, and intercept the fraction with a boiling point of 125° C. to obtain a pretreated raw material; Step 2: The pre-treated raw material is subjected to impurity removal treatment. The pre-treated raw material is passed into an adsorption bed filled with an adsorbent. The amount of the adsorbent is 5% of the mass of the pre-treated raw material to remove impurities. Step 3, the pretreated raw material for removing impurities and the diluent toluene are added to the reactor, stirred and mixed evenly, and the catalyst is slowly added in a nitrogen atmosphere. The mass ratio of the pretreated raw material for removing impurities, the diluent toluene, and the catalyst is 100:18:1.5. The catalyst is a composite catalyst, and the composite catalyst is composed of a ZSM-5 molecular sieve and p-toluenesulfonic acid with a mass ratio of 1:0.5, wherein the silicon-aluminum molar ratio of the ZSM-5 molecular sieve is 50:1, and the reaction is carried out at 35 ° C for 3h, and a 5wt% sodium carbonate aqueous solution is added to terminate the reaction. After the reaction is completed, centrifugation is performed, and the supernatant is subjected to reduced pressure distillation. The reduced pressure distillation temperature is 240 ° C, and the vacuum degree is -0.095MPa. After reduced pressure distillation, a polymer product is obtained; Step 4: Activate the hydrogenation catalyst, activate the hydrogenation catalyst at 200°C and 0.5MPa hydrogen pressure for 2h, mix the polymerization product and cyclohexane evenly, add them to the reactor, introduce hydrogen into the reactor, adjust the pressure of the reactor to 5MPa, add the activated hydrogenation catalyst, wherein the mass ratio of the polymerization product, cyclohexane and the activated hydrogenation catalyst is 100:1000:10, stir and mix, and carry out hydrogenation reaction. During the hydrogenation reaction, add hydrogen every 20min, maintain the pressure in the reactor at 5MPa, the reaction temperature at 235°C, the reaction time at 2h, and the rotation speed at 500r / min. After the reaction is completed, separate the product, take the liquid phase for distillation, and obtain a light-colored carbon nine petroleum resin.

[0045] The adsorbent used was the maleic anhydride-modified TiO2 / biochar composite adsorbent prepared in Example 2, and the hydrogenation catalyst used was the Ni / Al2O3 / TiO2 catalyst prepared in Example 5.

[0046] Comparative Example 1 A method for preparing a carbon nine petroleum resin comprises the following steps: Step 1: distill the C9 fraction, a by-product of ethylene cracking, under reduced pressure in a vacuum distillation tower at a vacuum degree of -0.095 MPa, and intercept the fraction with a boiling point of 150° C. to obtain a pretreated raw material; Step 2: The pretreated raw material is subjected to impurity removal treatment. The pretreated raw material is passed through an adsorption bed filled with an adsorbent. The adsorbent is composed of titanium dioxide and biochar in a mass ratio of 9:20. The amount of the adsorbent is 4% of the mass of the pretreated raw material to remove impurities. Step 3, the pretreated raw material for removing impurities and the diluent toluene are added to the reactor, stirred and mixed evenly, and the catalyst is slowly added in a nitrogen atmosphere. The mass ratio of the pretreated raw material for removing impurities, the diluent toluene, and the catalyst is 100:15:1.2. The catalyst is a composite catalyst, and the composite catalyst is composed of a ZSM-5 molecular sieve and p-toluenesulfonic acid with a mass ratio of 1:0.4, wherein the silicon-aluminum molar ratio of the ZSM-5 molecular sieve is 45:1. The reaction is carried out at 30°C for 4h, and a 5wt% aqueous sodium carbonate solution is added to terminate the reaction. After the reaction is completed, the reaction is centrifuged and the supernatant is subjected to reduced pressure distillation. The reduced pressure distillation temperature is 220°C and the vacuum degree is -0.095MPa. After reduced pressure distillation, a polymer product is obtained; Step 4: Activate the hydrogenation catalyst, activate the hydrogenation catalyst at 200°C and 0.5MPa hydrogen pressure for 2h, mix the polymerization product and cyclohexane evenly, add them to the reactor, introduce hydrogen into the reactor, adjust the pressure of the reactor to 4.5MPa, add the activated hydrogenation catalyst, wherein the mass ratio of the polymerization product, cyclohexane and the activated hydrogenation catalyst is 100:950:8, stir and mix, and carry out hydrogenation reaction. During the hydrogenation reaction, add hydrogen every 20min, maintain the pressure in the reactor at 4.5MPa, the reaction temperature at 230°C, the reaction time at 2h, and the rotation speed at 500r / min. After the reaction is completed, separate the product, take the liquid phase for distillation, and obtain C9 petroleum resin.

[0047] The hydrogenation catalyst used was the Ni / Al2O3 / TiO2 catalyst prepared in Example 5.

[0048] Comparative Example 2 A method for preparing a carbon nine petroleum resin comprises the following steps: Step 1: distill the C9 fraction, a by-product of ethylene cracking, under reduced pressure in a vacuum distillation tower at a vacuum degree of -0.095 MPa, and intercept the fraction with a boiling point of 150° C. to obtain a pretreated raw material; Step 2: The pretreated raw material is subjected to impurity removal treatment. The pretreated raw material is passed into an adsorption bed filled with an adsorbent. The amount of the adsorbent is 4% of the mass of the pretreated raw material to remove impurities. Step 3, the pretreated raw material for removing impurities and the diluent toluene are added to the reactor, stirred and mixed evenly, and the catalyst is slowly added in a nitrogen atmosphere. The mass ratio of the pretreated raw material for removing impurities, the diluent toluene, and the catalyst is 100:15:1.2. The catalyst is a composite catalyst, and the composite catalyst is composed of a ZSM-5 molecular sieve and p-toluenesulfonic acid with a mass ratio of 1:0.4, wherein the silicon-aluminum molar ratio of the ZSM-5 molecular sieve is 45:1. The reaction is carried out at 30°C for 4h, and a 5wt% aqueous sodium carbonate solution is added to terminate the reaction. After the reaction is completed, the reaction is centrifuged and the supernatant is subjected to reduced pressure distillation. The reduced pressure distillation temperature is 220°C and the vacuum degree is -0.095MPa. After reduced pressure distillation, a polymer product is obtained; Step 4: Activate the hydrogenation catalyst. Activate the hydrogenation catalyst Al2O3 at 200°C and 0.5MPa hydrogen pressure for 2h. Mix the polymer product and cyclohexane evenly and add them to the reactor. Add hydrogen into the reactor and adjust the pressure of the reactor to 4.5MPa. Add the activated hydrogenation catalyst Al2O3. The mass ratio of the polymer product, cyclohexane and the activated hydrogenation catalyst Al2O3 is 100:950:8. Stir and mix to carry out hydrogenation reaction. During the hydrogenation reaction, add hydrogen every 20min to maintain the pressure in the reactor at 4.5MPa, the reaction temperature is 230°C, the reaction time is 2h, and the rotation speed is 500r / min. After the reaction is completed, separate the product and perform liquid phase distillation to obtain C9 petroleum resin.

[0049] The adsorbent used was the maleic anhydride-modified TiO2 / biochar composite adsorbent prepared in Example 2.

[0050] Comparative Example 3 A method for preparing a carbon nine petroleum resin comprises the following steps: Step 1: distill the C9 fraction, a by-product of ethylene cracking, under reduced pressure in a vacuum distillation tower at a vacuum degree of -0.095 MPa, and intercept the fraction with a boiling point of 150° C. to obtain a pretreated raw material; Step 2: Add the pretreated raw material and the diluent toluene to the reactor, stir and mix evenly, and slowly add the catalyst in a nitrogen atmosphere. The mass ratio of the pretreated raw material, the diluent toluene, and the catalyst is 100:15:1.2. The catalyst is a composite catalyst, and the composite catalyst is composed of ZSM-5 molecular sieve and p-toluenesulfonic acid with a mass ratio of 1:0.4, wherein the silicon-aluminum molar ratio of the ZSM-5 molecular sieve is 45:1. The reaction is carried out at 30°C for 4h, and a 5wt% sodium carbonate aqueous solution is added to terminate the reaction. After the reaction is completed, centrifugation is performed, and the supernatant is subjected to reduced pressure distillation. The reduced pressure distillation temperature is 220°C and the vacuum degree is -0.095MPa. After reduced pressure distillation, a polymer product is obtained; Step 3: Activate the hydrogenation catalyst, activate the hydrogenation catalyst at 200°C and 0.5MPa hydrogen pressure for 2h, mix the polymerization product and cyclohexane evenly, add them to the reactor, introduce hydrogen into the reactor, adjust the pressure of the reactor to 4.5MPa, add the activated hydrogenation catalyst, wherein the mass ratio of the polymerization product, cyclohexane and the activated hydrogenation catalyst is 100:950:8, stir and mix, and carry out hydrogenation reaction. During the hydrogenation reaction, add hydrogen every 20min, maintain the pressure in the reactor at 4.5MPa, the reaction temperature at 230°C, the reaction time at 2h, and the rotation speed at 500r / min. After the reaction is completed, separate the product, take the liquid phase for distillation, and obtain carbon nine petroleum resin.

[0051] The hydrogenation catalyst used was the Ni / Al2O3 / TiO2 catalyst prepared in Example 5.

[0052] Comparative Example 4 A method for preparing a carbon nine petroleum resin comprises the following steps: Step 1: distill the C9 fraction, a by-product of ethylene cracking, under reduced pressure in a vacuum distillation tower at a vacuum degree of -0.095 MPa, and intercept the fraction with a boiling point of 150° C. to obtain a pretreated raw material; Step 2: The pretreated raw material is subjected to impurity removal treatment. The pretreated raw material is passed into an adsorption bed filled with an adsorbent. The amount of the adsorbent is 4% of the mass of the pretreated raw material to remove impurities. Step 3: Add the pretreated raw material from which impurities have been removed and the diluent toluene into the reactor, stir and mix evenly, and slowly add the catalyst in a nitrogen atmosphere. The mass ratio of the pretreated raw material from which impurities have been removed, the diluent toluene, and the catalyst is 100:15:1.2. The catalyst is a composite catalyst, and the composite catalyst is composed of ZSM-5 molecular sieve and p-toluenesulfonic acid in a mass ratio of 1:0.4, wherein the silicon-aluminum molar ratio of the ZSM-5 molecular sieve is 45:1. The reaction is carried out at 30°C for 4h, and a 5wt% aqueous sodium carbonate solution is added to terminate the reaction. After the reaction is completed, the mixture is centrifuged and the supernatant is taken for vacuum distillation. The vacuum distillation temperature is 220°C and the vacuum degree is -0.095MPa. After vacuum distillation, carbon nine petroleum resin is obtained.

[0053] The adsorbent used was the maleic anhydride-modified TiO2 / biochar composite adsorbent prepared in Example 2.

[0054] The biochar used in the examples and comparative examples of the present invention was purchased from Jiangsu Enkai Activated Carbon Co., Ltd., model wood powder activated carbon 07; nano titanium dioxide was purchased from Xuancheng Jingrui New Materials Co., Ltd., model JR05, with an average particle size of 5 nm; other reagents were commercially available.

[0055] The relevant performance tests of the C9 petroleum resins prepared in Examples 7-9 and Comparative Examples 1-4 were conducted as follows: (1) Chromaticity test: The chromaticity test was carried out in accordance with the standard of GB / T 22295-2008. 10g of C9 petroleum resin was dissolved in 10g of toluene. After the mixture was evenly dissolved, the chromaticity was tested using a Ghana colorimeter at a constant temperature of 25±0.5℃, under a D65 light source and vertical observation. The color was compared with the Ghana color standard color disk. Each group was tested five times and the average value was taken. (2) Softening point test: According to the standard of GB / T 4507-2014, the instantaneous temperature of the support plate when the resin contacts the bottom is the softening point. Each group is tested five times and the average value is taken; (3) Bromine value test: Calculate the bromine value according to GB / T 11135-2013. Test each group five times and take the average value. (4) Thermal stability test: Take 10 mg of C9 petroleum resin sample and perform thermogravimetric analysis in a nitrogen atmosphere at a heating rate of 10 °C / min in the temperature range of 25 °C to 600 °C. Record the initial decomposition temperature (T) at which the mass loss is 5%. 5% , Each group was tested five times and the average value was taken; The test results are shown in Table 1: Test items Example 7 Example 8 Example 9 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Chroma (Ghana color number) 2.5 2.0 2.2 5.0 4.5 6.5 8.0 Softening point (℃) 96.4 102.3 101.9 95.8 98.5 92.4 101.2 Bromine value (gBr / 100g) 3.1 2.5 2.7 3.9 18.6 21.1 40.4 <![CDATA[T 5% (℃)]]> 305 318 320 299 278 274 263 Table 1 The test results in Table 1 show that the C9 petroleum resins prepared in Examples 7-9 of the present invention have low chroma. During the polymerization process, the use of ZSM-5 molecular sieve and organic sulfonic acid as a composite catalyst effectively regulates the molecular weight distribution of the polymer product, resulting in an improved softening point. Furthermore, the degree of olefinic unsaturation is low, reducing unstable structures and exhibiting excellent heat resistance and chemical stability. In Comparative Example 1, titanium dioxide and biochar were used as adsorbents instead of the maleic anhydride-modified TiO2 / biochar composite adsorbent, resulting in improved chroma with minimal impact on bromine value. Metal impurities were catalytically cracked, lowering the softening point. In Comparative Example 2, Al2O3 was used as a hydrogenation catalyst instead of the Ni / Al2O3 / TiO2 catalyst, lacking hydrogenation active sites. This reduced thermal stability, improved chroma, and increased bromine value. In Comparative Example 3, no decontamination treatment was performed, resulting in reduced overall performance. In Comparative Example 4, while hydrogenation was omitted, a high molecular weight product was still produced, achieving a softening point similar to that of the Examples, but with significantly reduced thermal stability, a high number of residual double-bond chromophores, high chroma, and a darker resin color.

[0056] Although the embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations may be made to these embodiments without departing from the principles and spirit of the present invention, and that all equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the present invention.

Claims

1. A method for preparing a light-colored carbon nine petroleum resin, characterized by: The method comprises the following steps: pre-treating a C9 fraction, a by-product of ethylene cracking, passing the pre-treated raw material into an adsorption bed containing an adsorbent for impurity removal, mixing the pre-treated raw material after impurities are removed, a diluent, and a catalyst to react to obtain a polymer product, uniformly mixing the polymer product with cyclohexane, activating a hydrogenation catalyst, stirring and mixing, performing a hydrogenation reaction, and rectifying after the reaction to obtain a light-colored C9 petroleum resin; The adsorbent is a maleic anhydride modified TiO2 / biochar composite adsorbent; The hydrogenation catalyst is a Ni / Al2O3 / TiO2 catalyst.

2. The method for preparing a light-colored C9 petroleum resin according to claim 1, characterized in that: The specific steps include: Step 1: distilling the ethylene cracking by-product C9 fraction under reduced pressure in a vacuum distillation tower at a vacuum degree of -0.092 MPa to -0.098 MPa, intercepting the fraction with a boiling point of 125°C to 155°C to obtain a pretreated raw material; Step 2: The pre-treated raw material is subjected to impurity removal treatment, and the pre-treated raw material is passed into an adsorption bed filled with an adsorbent to remove impurities; Step 3: adding the pretreated raw material from which impurities have been removed and the diluent to the reactor, stirring and mixing uniformly, slowly adding the catalyst in a nitrogen atmosphere to react, adding a 5 wt % aqueous sodium carbonate solution to terminate the reaction, and after the reaction is completed, centrifuging and separating, taking the supernatant and performing vacuum distillation at a vacuum distillation temperature of 200-240° C. and a vacuum degree of -0.095 MPa to obtain a polymer product; Step 4: Activate the hydrogenation catalyst, mix the polymerization product with cyclohexane evenly, add them to the reactor, introduce hydrogen into the reactor, adjust the pressure of the reactor to 4-5 MPa, add the activated hydrogenation catalyst, stir and mix, and carry out hydrogenation reaction. After the reaction is completed, separate the product, take liquid phase distillation, and obtain light-colored carbon nine petroleum resin.

3. The method for preparing a light-colored C9 petroleum resin according to claim 2, characterized in that: The preparation method of the maleic anhydride modified TiO2 / biochar composite adsorbent in step 2 comprises the following steps: A1. Add deionized water and titanium tetrachloride to reactor A, disperse evenly by ultrasonication, then add biochar, heat and stir to react, adjust the pH to neutral, wash with deionized water, and dry to obtain TiO2 / biochar; A2. Add methanol and TiO2 / biochar to reactor B, disperse them uniformly by ultrasonication, then add γ-aminopropyltriethoxysilane, stir and mix, and react. After the reaction is complete, filter, wash with anhydrous ethanol and deionized water, and dry to obtain amination-treated TiO2 / biochar. A3. Add dimethyl sulfoxide and amino TiO2 / biochar to reactor C, and after ultrasonic dispersion, add maleic anhydride, dicyclohexylcarbodiimide and 4-dimethylaminopyridine, stir and mix, and react. After the reaction is completed, filter, wash with ethyl acetate and deionized water, and dry to obtain a maleic anhydride-modified TiO2 / biochar composite adsorbent.

4. The method for preparing a light-colored C9 petroleum resin according to claim 3, characterized in that: The mass ratio of deionized water, titanium tetrachloride and biochar in A1 is 3800-4500:75-120:100, the reaction temperature is 65-95° C., and the reaction time is 4-8 hours.

5. The method for preparing a light-colored C9 petroleum resin according to claim 3, characterized in that: The mass ratio of methanol, TiO2 / biochar, and γ-aminopropyltriethoxysilane in A2 is 2000-2400:100:18-25, the reaction temperature is 55-65°C, and the reaction time is 5-7h.

6. The method for preparing a light-colored C9 petroleum resin according to claim 3, characterized in that: The mass ratio of dimethyl sulfoxide, amino TiO2 / biochar, maleic anhydride, dicyclohexylcarbodiimide and 4-dimethylaminopyridine in A3 is 1200-1500:100:50-80:30-42:8-15, the reaction temperature is 25-35°C, and the reaction time is 3-5h.

7. The method for preparing a light-colored C9 petroleum resin according to claim 2, characterized in that: In the step 3, the mass ratio of the pretreated raw material for removing impurities, the diluent, and the catalyst is 100:10-18:0.6-1.5, the reaction temperature is 0-35° C., the reaction time is 3-5 hours, and the diluent is toluene.

8. The method for preparing a light-colored C9 petroleum resin according to claim 2, characterized in that: The catalyst in step three is a composite catalyst, which is composed of ZSM-5 molecular sieve and organic sulfonic acid in a mass ratio of 1:0.1-0.

5.

9. The method for preparing a light-colored C9 petroleum resin according to claim 2, characterized in that: In the step 4, the mass ratio of the polymerization product, cyclohexane, and the activated hydrogenation catalyst is 100:900-1000:7-10. During the hydrogenation reaction, hydrogen is added every 20 minutes to maintain the pressure in the reactor at 4-5 MPa, the reaction temperature at 225-235° C., the reaction time at 2 hours, and the rotation speed at 500 r / min.

10. The method for preparing a light-colored C9 petroleum resin according to claim 2, characterized in that: The preparation method of the hydrogenation catalyst Ni / Al2O3 / TiO2 in step 4 comprises the following steps: Nickel nitrate, aluminum nitrate, and deionized water were mixed evenly and stirred until completely dissolved, titanium dioxide was added, ultrasonically dispersed for 30 minutes, 25wt% ammonia water was added to adjust the pH to 8-8.5, stirred and mixed, and reacted. After the reaction was completed, deionized water and anhydrous ethanol were used for washing, centrifugation, drying, and calcination in a muffle furnace to obtain a Ni / Al2O3 / TiO2 catalyst.