阅读说明：本技术 粗乙二醇加氢精制方法与加氢精制剂 (Hydrofining method and hydrofining agent for crude ethylene glycol ) 是由 陈梁锋 唐康健 朱俊华 于 2019-09-02 设计创作，主要内容包括：本发明涉及一种粗乙二醇加氢精制剂及乙二醇加氢精制方法,所述精制剂包括载体、活性组分和助剂,其中所述活性组分包括钌,所述助剂包括碱土金属氧化物和过渡金属氧化物中的至少一种。该精制剂用于粗乙二醇精制中能够使精制后的乙二醇紫外透过率高、储存过程中降低不明显,同时该精制剂稳定,使用寿命长。(The invention relates to a crude glycol hydrofining agent and a glycol hydrofining method, wherein the hydrofining agent comprises a carrier, an active component and an auxiliary agent, the active component comprises ruthenium, and the auxiliary agent comprises at least one of an alkaline earth metal oxide and a transition metal oxide. The refining agent is used for refining the crude glycol, so that the ultraviolet transmittance of the refined glycol is high, the reduction in the storage process is not obvious, and meanwhile, the refining agent is stable and has long service life.)

1. The crude glycol hydrofining agent comprises a carrier, an active component and an auxiliary agent, wherein the active component comprises ruthenium, and the auxiliary agent comprises at least one of an alkaline earth metal oxide and a transition metal oxide.

2. The refining agent according to claim 1, wherein the transition metal oxide is selected from at least one of oxides of Ni, Zn, Co, and Mn, preferably from at least one of oxides of Ni and Zn; the alkaline earth metal oxide is selected from at least one of oxides of Mg and Ca.

3. The refining agent according to claim 1 or 2, characterized in that the support is selected from one or more of alumina, silica and molecular sieves, preferably from one or more of theta-alumina, eta-alumina, gamma-alumina, more preferably gamma-alumina, further preferably the gamma-alumina precursor comprises one or more of amorphous aluminium hydroxide, boehmite and boehmite, preferably pseudoboehmite or boehmite.

4. The refining agent according to any one of claims 1 to 3, wherein the refining agent comprises, in parts by weight:

0.1 to 10 parts, preferably 0.5 to 4 parts, more preferably 1 to 3 parts of active ingredient;

0.5-15 parts, preferably 1-9 parts, more preferably 4-6 parts of auxiliary agent;

75-99.4 parts, preferably 87-98.5 parts, more preferably 91-95 parts of carrier.

5. The refining agent according to any one of claims 1 to 4, wherein the specific surface area of the carrier is 240-320m²Per g, preferably 250-300m²(ii)/g; and/or the pore volume of the carrier is 0.30-0.80mL/g, preferably 0.40-0.60 mL/g.

6. A process for the preparation of a refining agent as defined in any of claims 1 to 5, comprising the steps of:

(I) providing a solution I comprising a soluble salt of the active component and a soluble salt of the adjuvant;

(II) mixing the carrier with the solution I, drying and roasting to obtain a refining agent precursor;

(III) reducing the precursor of the refining agent by using a reducing agent to obtain the refining agent.

7. The method according to claim 6, wherein the soluble salt in the step (I) is at least one selected from the group consisting of halide salt, nitrate salt and sulfate salt; and/or the presence of a gas in the gas,

the roasting temperature in the step (II) is 300-600 ℃, and the roasting time is 2-6 h; and/or the presence of a gas in the gas,

in the step (III), the reducing agent is hydrogen, the reduction treatment pressure is 0.1-1MPa, and the hourly space velocity of the reducing agent gas is 200-^-1The reduction temperature is 120-200 ℃, and the reduction time is 2-10 h.

8. A process for hydrorefining crude ethylene glycol, which comprises reacting crude ethylene glycol with hydrogen in the presence of the refining agent as defined in any one of claims 1 to 5 or the refining agent prepared by the process as defined in claim 6 or 7.

9. The process according to claim 8, wherein the reaction temperature is 60-140 ℃, preferably 80-120 ℃, more preferably 100-120 ℃;

and/or the reaction pressure is 0.2-3MPa, preferably 0.5-2.5MPa, more preferably 1.5-2.5 MPa;

and/or the mass space velocity of the crude glycol is 1-20h^-1Preferably 3-8h^-1More preferably 3-5h^-1；

And/or the feeding volume ratio of the reducing agent to the crude glycol is 200-.

10. Use of the refining agent of any one of claims 1 to 5 or the refining agent obtained by the method of claim 6 or 7 or the method of claim 8 or 9 in the refining of crude ethylene glycol.

Technical Field

The invention relates to a method for refining crude glycol, in particular to preparation of a Ru-based refining agent and application of the Ru-based refining agent in refining glycol.

Background

Ethylene glycol (EG for short) is an important petrochemical basic organic raw material, and more than 100 chemicals can be derived from the ethylene glycol. The polyester (including polyester fiber, polyester bottle, polyester film, etc.) is the main consumption field of ethylene glycol in China, the consumption amount of the polyester accounts for about 90% of the total domestic consumption amount, and about 10% of the polyester is used for an antifreezing agent, an adhesive, a paint solvent, cold-resistant lubricating oil, a surfactant, etc. The current route for the industrial production of ethylene glycol can be mainly divided into a petroleum method and a synthesis gas method. The petroleum method is mainly to hydrate ethylene oxide generated after ethylene generated by naphtha cracking is oxidized to obtain ethylene glycol, although the production process is mature and stable, the production process has many defects, for example, ethylene oxidation in the production process can generate byproducts containing carbon-oxygen double bonds such as aldehyde, ketone, acid, ester and the like besides ethylene oxide, ethylene oxide can also be isomerized to aldehyde byproducts, and the species containing the carbon-oxygen double bonds can influence the permeability of ethylene glycol, thereby influencing the quality of the final ethylene glycol product. The synthesis gas method mainly comprises the steps of oxidizing and coupling CO in the synthesis gas to generate oxalate, and then hydrogenating the oxalate to obtain the ethylene glycol. In the hydrogenation process of oxalate, partial byproducts containing carbon-oxygen double bonds and influencing ultraviolet transmittance are generated due to incomplete hydrogenation, and the byproducts are carried to subsequent processes and influence the quality of the final ethylene glycol product. Therefore, the method is very important for removing the impurities containing carbon-oxygen double bonds, thereby improving the ultraviolet transmittance of the ethylene glycol and improving the quality of the ethylene glycol product.

Living et al (CN 102649688) use a supported copper catalyst to hydrogenate crude ethylene glycol, and can improve the ethylene glycol with the ultraviolet transmittance of less than 30% at 220nm to over 75%, thereby meeting the national high-grade standard.

Johnjin beam et al (CN 104945227) use a carbon-supported Raney nickel alloy as a hydrofinishing agent for ethylene glycol at 100 ℃, 0.5MPa, and space velocity of 6h^-1In the case of (2), the ultraviolet transmittance at 220nm can be improved from about 26% to more than 80%.

How to use the novel refining agent, the ultraviolet transmittance of the glycol can be greatly improved, the glycol can be used for a long time, and simultaneously, the UV value is not obviously reduced in the storage process, so that the method is a problem to be solved urgently in the industrial production practice.

Disclosure of Invention

One of the technical problems to be solved by the invention is to provide a hydrofining agent for crude glycol, which is used for the refining of crude glycol and can ensure that the ultraviolet transmittance of the refined glycol is high, the reduction in the storage process is not obvious, and the hydrofining agent is stable and has long service life.

The second technical problem to be solved by the invention is a preparation method of the refining agent corresponding to the first technical problem.

The third technical problem to be solved by the invention is to provide a novel method for refining ethylene glycol.

The invention provides a crude glycol hydrofining agent, which comprises a carrier, an active component and an auxiliary agent, wherein the active component comprises ruthenium, and the auxiliary agent comprises at least one of alkaline earth metal oxide and transition metal oxide.

According to some embodiments of the invention, the transition metal oxide is selected from at least one of the oxides of Ni, Zn, Co and Mn, such as NiO, ZnO, Co₃O₄And MnO₂。

According to some embodiments of the invention, the transition metal oxide is selected from at least one of Ni and Zn oxides, such as NiO or ZnO.

According to some embodiments of the invention, the alkaline earth metal oxide is selected from at least one of oxides of Mg and Ca, such as MgO.

According to some embodiments of the invention, the support is selected from one or more of alumina, silica and molecular sieves.

According to some embodiments of the invention, the support is selected from one or more of theta alumina, eta alumina, gamma alumina.

According to some embodiments of the invention, the support is gamma-alumina.

According to some embodiments of the invention, the gamma-alumina precursor comprises one or more of amorphous aluminum hydroxide, pseudoboehmite, and boehmite, preferably pseudoboehmite or boehmite.

According to some embodiments of the invention, the refining agent comprises 0.1 to 10 parts by weight of active ingredient, 0.5 to 15 parts by weight of auxiliary agent and 75 to 99.4 parts by weight of carrier.

According to some embodiments of the invention, the refining agent comprises 0.5-4 parts by weight of active component, 1-9 parts by weight of auxiliary agent and 87-98.5 parts by weight of carrier.

According to some embodiments of the invention, the refining agent comprises 1-3 parts by weight of active component, 4-6 parts by weight of auxiliary agent and 91-95 parts by weight of carrier.

According to some embodiments of the invention, the specific surface area of the support is 240-320m²A value of/g, for example 240m²/g、250m²/g、255m²/g、259m²/g、260m²/g、270m²/g、280m²/g、290m²/g、296m²/g、300m²/g、310m²G and 320m²(iv)/g and any value therebetween, preferably 250 to 300m²/g.

According to some embodiments of the invention, the carrier has a pore volume of 0.30 to 0.80mL/g, for example, 0.30mL/g, 0.40mL/g, 0.45mL/g, 0.50mL/g, 0.55mL/g, 0.60mL/g, 0.65mL/g, 0.70mL/g, and 0.80mL/g and any value in between, preferably 0.40 to 0.60 mL/g.

The second aspect of the invention provides a preparation method of the refining agent, which comprises the following steps:

(I) providing a solution I comprising a soluble salt of the active component and a soluble salt of the adjuvant;

(II) mixing the carrier with the solution I, drying and roasting to obtain a refining agent precursor;

(III) reducing the precursor of the refining agent by using a reducing agent to obtain the refining agent.

According to some embodiments of the invention, the soluble salt in step (I) is selected from at least one of a halide salt, a nitrate salt and a sulfate salt.

According to some embodiments of the present invention, the temperature of the calcination in step (II) is 300-600 ℃, and the calcination time is 2-6 h.

According to some embodiments of the present invention, the reducing agent in step (III) is hydrogen, the reduction treatment pressure is 0.1-1MPa, and the hourly space velocity of the reducing agent gas is 200-^-1The reduction temperature is 120-200 ℃, and the reduction time is 2-10 h.

According to some preferred embodiments of the present invention, the refining agent is prepared by the following steps:

1) dissolving ruthenium chloride and metal salt of an auxiliary agent in deionized water at room temperature to obtain a steeping liquor; the alumina carrier is added to the impregnation solution and stirred for 20 minutes.

2) Drying the mixture obtained in the step 1) in an oven for 24 hours, and then roasting for 4 hours to obtain Al₂O₃A supported Ru-based refining agent precursor.

3) Loading the refining agent precursor obtained in the step 2) into a fixed bed reactor, and reducing by using hydrogen, wherein the pressure of the hydrogen is 0.1-1MPa, and the gas hourly space velocity is 200-^-1The reduction temperature is 120-₂O₃。

According to some preferred embodiments of the present invention, the metal salt of the auxiliary used in step 1) may be at least one of a halogen salt, a nitrate salt and a sulfate salt; the drying temperature used in the step 2) is 100-150 DEG C

The method adopts an impregnation method to load Ru and an auxiliary agent on an alumina carrier, and then reduces the Ru and the auxiliary agent by hydrogen to obtain the metallic Ru-based hydrofining agent loaded on alumina. The Ru and the auxiliary agent in the refining agent have synergistic effect, so that impurities containing carbon-oxygen double bonds in the crude glycol can be better removed.

In a third aspect, the invention provides a hydrofining method of crude ethylene glycol, which comprises the step of introducing ethylene glycol and hydrogen to react in the presence of the refining agent.

According to some embodiments of the present invention, the reaction temperature is 60-140 ℃, preferably 80-120 ℃, more preferably 100-120 ℃.

According to some embodiments of the invention, the reaction pressure is between 0.2 and 3MPa, preferably between 0.5 and 2.5MPa, more preferably between 1.5 and 2.5 MPa.

According to some embodiments of the invention, the ethylene glycol has a mass space velocity of 1 to 20h^-1Preferably 3-8h^-1More preferably 3-5h^-1。，

According to some embodiments of the present invention, the feed volume ratio (standard state) of the reducing agent to ethylene glycol is 200-.

The alumina-loaded Ru-based hydrofining agent is used for hydrofining of crude ethylene glycol, and the reaction temperature is 100 ℃, and the airspeed of the crude ethylene glycol is 5h^-1Under the conditions that the hydrogen pressure is 1.5MPa and the feeding volume ratio (standard state) of hydrogen to crude glycol is 600, the ultraviolet transmittance of the hydrofined glycol is respectively more than 90%, 95% and 99% at 220nm, 275nm and 350nm, the hydrofining activity can be maintained within 400 days, and the ultraviolet transmittance reduction amplitude of the refined glycol is less than 5% after the refined glycol is stored for 10 days.

The term "standard state" as used in the present invention refers to the standard state of a gas at a temperature of 25 ℃ and a pressure of 101.325 KPa.

The invention provides in a fourth aspect the use of a refining agent as described above or of a method as described above for the refining of crude ethylene glycol.

Detailed Description

The invention is further illustrated by the following examples. It is to be noted that the following examples are only for the purpose of further illustrating the present invention and should not be construed as limiting the scope of the present invention.

[ example 1 ]

27.9g of Carrier Al₂O₃-1(γ-Al₂O₃The precursor is boehmite with a specific surface area of 256m²0.55mL/g of pore volume) in 100mL of deionized water, adding 50mL of aqueous solution containing 1.21g of ruthenium chloride and 5.84g of nickel nitrate hexahydrate, stirring for 20min, baking the obtained mixture at 120 ℃ for 24h, roasting at 500 ℃ for 4h to obtain a catalyst precursor, putting 10g of the precursor in a fixed bed reactor, keeping the hydrogen pressure at 0.5MPa, the flow rate at 100mL/h (standard state), the reduction temperature at 150 ℃, the reduction time at 5h, and obtaining a hydrofining agent RA-1, wherein the weight part of Ru is 2.0, the assistant M is NiO, the weight part is 5.0, and the carrier Al is 5.0₂O₃-1 parts by weight 93.0.

[ example 2 ]

The hydrofining agent was prepared in the same manner as in example 1, except that 5.51g of zinc nitrate hexahydrate as the adjuvant salt was used, and the hydrofining agent obtained was RA-2 in which 2.0 parts by weight of Ru was used, 5.0 parts by weight of ZnO as the adjuvant M, and Al as the carrier₂O₃-1 parts by weight 93.0.

[ example 3 ]

The hydrofining agent was prepared in the same manner as in example 1, except that 9.62g of magnesium nitrate hexahydrate as the adjuvant salt was used, and the hydrofining agent obtained was RA-3, in which 2.0 parts by weight of Ru, 5.0 parts by weight of MgO as the adjuvant M, and Al as the carrier₂O₃-1 parts by weight 93.0.

[ example 4 ]

The hydrofining agent was prepared in the same manner as in example 1, except that 5.46g of cobalt nitrate hexahydrate as the salt of the adjuvant was used, and the hydrofining agent obtained was RA-4, in which 2.0 parts by weight of Ru and Co as the adjuvant M were used₃O₄5.0 parts by weight of carrier Al₂O₃-1 parts by weight 93.0.

[ example 5 ]

The hydrofining agent was prepared in the same manner as in example 1, except that 6.17g of a 50 wt% manganese nitrate solution as the additive salt was used, and the hydrofining agent obtained was RA-5, in which the weight fraction of Ru was 2.0 and the additive M was MnO₂Parts by weightNumber 5.0, support Al₂O₃-1 parts by weight 93.0.

[ example 6 ]

Hydrofinishing agent was prepared in the same manner as in example 1, except that the carrier used was Al₂O₃-2(γ-Al₂O₃The precursor is boehmite with specific surface area of 296m²Perg, the pore volume is 0.45mL/g), the obtained hydrofining agent is RA-6, wherein the weight part of Ru is 2.0, the assistant M is NiO, the weight part is 5.0, and the carrier Al is₂O₃-2 parts by weight 93.0.

[ example 7 ]

The hydrofinishing agent was prepared in the same manner as in example 1 except that 0.30g of ruthenium chloride was used, 8.60g of nickel chloride hexahydrate as the adjuvant salt, and Al as the carrier₂O₃27.2g of-1, and the obtained hydrofining agent RA-7, wherein the weight portion of Ru is 0.5, the weight portion of the auxiliary agent M is NiO and is 9.0, and the carrier Al is₂O₃The weight portion of-1 is 90.5.

[ example 8 ]

The hydrofining agent was prepared in the same manner as in example 1, except that 2.42g of ruthenium chloride was used, 1.75g of nickel nitrate hexahydrate was used as the adjuvant salt, and Al as the carrier was used₂O₃The mass of the-1 is 28.4g, the obtained hydrofining agent is RA-8, wherein the weight part of Ru is 4.0, the weight part of the auxiliary agent M is NiO, the weight part of the auxiliary agent M is 1.5, and the carrier Al is₂O₃-1 parts by weight is 94.5.

Comparative example 1

Hydrofining agent was prepared in the same manner as in example 1, except that no adjuvant salt was added and Al as the carrier was used₂O₃The mass of the-1 is 29.4g, the obtained hydrofining agent is CRA-1, wherein the weight part of Ru is 2.0, and a carrier Al₂O₃The weight portion of-1 is 98.0.

Comparative example 2

The hydrofining agent was prepared in the same manner as in example 1 except that no adjuvant salt was added and Al was used as the carrier₂O₃-2, mass 294g, the obtained hydrofining agent is CRA-2, wherein the weight part of Ru is 2.0, and a carrier Al₂O₃The weight portion of-2 is 98.0.

Comparative example 3

The hydrofining agent was prepared in the same manner as in example 1, except that no adjuvant salt was added and Al as the carrier was used₂O₃27.9g of-1, 4.30g of ruthenium chloride and CRA-3 as the obtained hydrofining agent, wherein the weight part of Ru is 7.0, and Al as a carrier₂O₃-1 parts by weight 93.0.

Comparative example 4

The hydrofining agent was prepared in the same manner as in example 1, except that no active ingredient was added and Al as a carrier was used₂O₃27.9g of-1, 8.15g of auxiliary agent nickel nitrate hexahydrate and CRA-4 serving as an obtained hydrofining agent, wherein the weight part of NiO is 7.0, and Al serving as a carrier₂O₃-1 parts by weight 93.0.

Comparative example 5

The hydrofining agent was prepared in the same manner as in example 1, except that no active ingredient was added and Al as a carrier was used₂O₃27.9g of-1, 7.70g of auxiliary agent zinc nitrate hexahydrate and CRA-4 serving as an obtained hydrofining agent, wherein the weight part of ZnO is 7.0, and Al serving as a carrier₂O₃-1 parts by weight 93.0.

Comparative example 6

The hydrofining agent was prepared in the same manner as in example 1, except that no active ingredient was added and Al as a carrier was used₂O₃27.9g of-1, 13.4g of auxiliary agent magnesium nitrate hexahydrate and CRA-6 serving as an obtained hydrofining agent, wherein the weight part of MgO is 7.0, and Al serving as a carrier₂O₃-1 parts by weight 93.0.

Comparative example 7

The hydrofining agent was prepared in the same manner as in example 1, except that no active ingredient was added and Al as a carrier was used₂O₃The mass of the-1 is 27.9g, the mass of the used auxiliary agent cobalt nitrate hexahydrate is 8.18g, and the obtained hydrofining agent is CRA-7, wherein Co is₃O₄Is 7.0 parts by weight of carrier Al₂O₃-1 parts by weight 93.0.

Comparative example 8

The hydrofining agent was prepared in the same manner as in example 1, except that no active ingredient was added and Al as a carrier was used₂O₃27.9g of-1, 8.64g of a 50% manganese nitrate solution as an auxiliary agent, and CRA-8 as a hydrofining agent, wherein MnO was used₂Is 7.0 parts by weight of carrier Al₂O₃-1 parts by weight 93.0.

[ example 9 ]

Putting 110.0 g of hydrofining agent RA-prepared in example 1 into a fixed bed reactor, controlling the temperature at 100 ℃, adding hydrogen, controlling the hydrogen pressure at 1.5MPa and the flow rate at 460mL/min, uniformly passing crude ethylene glycol (the mass percentage content is 99.8%, the ultraviolet transmittances are 45.1%, 66.3% and 90.5% at 220nm, 275nm and 350nm respectively) through a hydrofining agent bed layer at the speed of 50.0g/h, and the mass space velocity is 5.0h^-1And the volume ratio (standard state) of the hydrogen to the ethylene glycol is 600, and the ultraviolet transmittance of the obtained refined ethylene glycol is respectively 92.1%, 98.0% and 99.9% at 220nm, 275nm and 350 nm. The obtained refined ethylene glycol is added in N₂The product is stored for 10 days under protection, and the ultraviolet transmittance of the product is respectively 91.5%, 97.5% and 99.9% at 220nm, 275nm and 350 nm.

[ examples 10 to 24 ]

The hydrorefining agents RA-2 to RA-8 and CRA1 to CRA-8 obtained in examples 2 to 8 and comparative examples 1 to 9 were subjected to a hydrorefining experiment under the hydrorefining conditions used in example 9, and the results are shown in Table 1.

TABLE 1

[ example 25 ]

The conditions were the same as in example 9 except that the feeding rate of the crude ethylene glycol was 80.0g/h and the amount of hydrogen fed was 740mL/min, to obtain refined ethylene glycol, whose ultraviolet transmittances were measured to be 90.3%, 97.1% and 99.9% at 220nm, 275nm and 350nm, respectively. The obtained refined ethylene glycol is added in N₂The product is stored for 10 days under protection, and the ultraviolet transmittance of the product is respectively 89.1%, 97.0% and 99.9% at 220nm, 275nm and 350 nm.

[ example 26 ]

The conditions were the same as in example 9 except that the feeding rate of the crude ethylene glycol was 30.0g/h and the amount of hydrogen fed was 280mL/min, to obtain refined ethylene glycol, whose ultraviolet transmittances were measured to be 92.5%, 98.1% and 99.9% at 220nm, 275nm and 350nm, respectively. The obtained refined ethylene glycol is added in N₂The product is stored for 10 days under protection, and the ultraviolet transmittance of the product is respectively 92.0%, 98.0% and 99.9% at 220nm, 275nm and 350 nm.

[ example 27 ]

The conditions were the same as in example 9 except that the reaction temperature was 80 ℃ to obtain refined ethylene glycol whose ultraviolet transmittances were measured to be 85.3%, 96.9% and 99.7% at 220nm, 275nm and 350nm, respectively. The obtained refined ethylene glycol is added in N₂The product is stored for 10 days under protection, and the ultraviolet transmittance of the product is respectively 84.2%, 96.2% and 99.6% at 220nm, 275nm and 350 nm.

[ example 28 ]

The conditions were the same as in example 9 except that the reaction temperature was 120 ℃ to obtain refined ethylene glycol, and the ultraviolet transmittances thereof were measured to be 92.6%, 98.5% and 99.9% at 220nm, 275nm and 350nm, respectively. The obtained refined ethylene glycol is added in N₂The product is stored for 10 days under protection, and the ultraviolet transmittance of the product is respectively 91.6%, 98.2% and 99.9% at 220nm, 275nm and 350 nm.

[ example 29 ]

ConditionSimilarly [ example 9 ] except that the flow rate of hydrogen was 920mL/min and the feed volume ratio of hydrogen to crude ethylene glycol (standard) was 1200, refined ethylene glycol was obtained, and the UV transmittances were measured to be 92.8%, 98.6% and 99.9% at 220nm, 275nm and 350nm, respectively. The obtained refined ethylene glycol is added in N₂The product is stored for 10 days under protection, and the ultraviolet transmittance of the product is respectively 92.0%, 98.4% and 99.9% at 220nm, 275nm and 350 nm.

[ example 30 ]

The conditions were the same as in example 9 except that the flow rate of hydrogen was 230mL/min and the feed volume ratio (standard) of hydrogen to crude ethylene glycol was 300 to give refined ethylene glycol, which was measured to have UV transmittances of 91.1%, 97.0% and 99.9% at 220nm, 275nm and 350nm, respectively. The obtained refined ethylene glycol is added in N₂The product is stored for 10 days under protection, and the ultraviolet transmittance of the product is respectively 89.8%, 96.8% and 99.9% at 220nm, 275nm and 350 nm.

[ example 31 ]

The conditions were the same as in example 9 except that the pressure of hydrogen was 0.5MPa, and refined ethylene glycol was obtained, and the ultraviolet transmittances thereof were measured to be 88.1%, 97.1% and 99.8% at 220nm, 275nm and 350nm, respectively. The obtained refined ethylene glycol is added in N₂The product is stored for 10 days under protection, and the ultraviolet transmittance of the product is respectively 87.5%, 96.9% and 99.8% at 220nm, 275nm and 350 nm.

[ example 32 ]

The conditions were the same as in example 9 except that the pressure of hydrogen was 2.5MPa, and refined ethylene glycol was obtained, and the ultraviolet transmittances thereof were measured to be 93.0%, 98.6% and 99.9% at 220nm, 275nm and 350nm, respectively. The obtained refined ethylene glycol is added in N₂The product is stored for 10 days under protection, and the ultraviolet transmittance of the product is respectively 92.6%, 98.3% and 99.9% at 220nm, 275nm and 350 nm.

[ example 33 ]

The life test of the hydrofinishing agent RA-1 was carried out under the conditions as described in example 9, and the results are shown in Table 2.

TABLE 2

It should be noted that the above-mentioned embodiments are only for explaining the present invention, and do not set any limit to the present invention. The present invention has been described with reference to exemplary embodiments, but the words which have been used herein are words of description and illustration, rather than words of limitation. The invention can be modified, as prescribed, within the scope of the claims and without departing from the scope and spirit of the invention. Although the invention has been described herein with reference to particular means, materials and embodiments, the invention is not intended to be limited to the particulars disclosed herein, but rather extends to all other methods and applications having the same functionality.