Bimetal Ni-Pt / RFE hydroisomerization catalyst as well as preparation method and application thereof

Abstract

The invention belongs to the field of petrochemical engineering, and discloses a bimetallic Ni-Pt / RFE hydroisomerization catalyst and a preparation method and application thereof. The preparation method comprises the following steps: dissolving a nickel precursor in water, stirring until clarification, and dropwise adding ammonia water to obtain a mixed solution 1; rFE is added into the mixed solution 1, the pH value is adjusted to be 9-11.5, suction filtration, washing and drying are conducted after stirring, and Ni / RFE is obtained; dissolving a platinum precursor in water, stirring until the solution is clear, and dropwise adding ammonia water to obtain a mixed solution 2; and adding the Ni / RFE into the mixed solution 2, adjusting the pH value to 9-11.5, stirring, and carrying out suction filtration, washing, drying and roasting to obtain the Ni-Pt / RFE. The method is simple and convenient to operate and mild in condition, the catalyst activity and the isomerization efficiency are remarkably improved through the synergistic effect of Ni and Pt, the catalyst preparation cost is greatly reduced while the use amount of precious metal is reduced, efficient conversion of long straight-chain alkane can be achieved, and the isomerization conversion rate of n-dodecane within 60 minutes can reach nearly 90%.

Description

Technical Field

[0001] This invention belongs to the field of petrochemicals, specifically relating to a bimetallic Ni-Pt / RFE hydroisomerization catalyst, its preparation method, and its application. Background Technology

[0002] Long-chain alkane isomerization is a crucial catalytic conversion process in clean energy production, widely used in biodiesel, aviation kerosene, and lubricating oil base oils. Through isomerization, C4–C7 short-chain n-alkanes can be converted into isoalkanes with high octane numbers for use as fuel gasoline, improving its anti-knock performance; C8–C... 15 Isomerization of long-chain n-alkane can lower the pour point while increasing the cetane number of diesel and jet fuels; C 16 The above-mentioned oils and waxes can also be isomerized to lower their pour points, thereby obtaining lubricating oils with good low-temperature fluidity. Traditional isomerization catalysts consist of two basic components: an acidic group responsible for skeletal rearrangement and a metal group serving as the (de)hydrogenation center. The acidic component is typically a solid acid, such as zirconium sulfate or zeolite, while the metal component includes noble metals (such as Pt, Pd), non-noble metals (such as Ni, Fe), or noble metal analogs such as Ni₂P. Therefore, how to prepare catalysts with high hydrogenation activity at low cost to completely convert long-chain alkanes in petroleum products into isomers to meet the China VI standard has always been a research hotspot in the petrochemical field. Many isomerization catalysts inevitably use Pt as the metal component, while using non-noble metals such as Ni as noble metal substitutes is often considered the best way to reduce catalyst preparation costs. Summary of the Invention

[0003] The first technical problem to be solved by the present invention is to provide a bimetallic Ni-Pt / RFE hydroisomerization catalyst to overcome the problems of weak interaction between noble metal and support, easy sintering and deactivation, and complex preparation process that easily damages molecular sieve channels in the prior art.

[0004] The second technical problem to be solved by the present invention is to provide a method for preparing the above-mentioned bimetallic Ni-Pt / RFE hydroisomerization catalyst.

[0005] The second technical problem to be solved by the present invention is to provide the application of the above-mentioned bimetallic Ni-Pt / RFE hydroisomerization catalyst in hydroisomerization catalytic reactions.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0007] A method for preparing a bimetallic Ni-Pt / RFE hydroisomerization catalyst includes the following steps: (1) Dissolve the nickel precursor in water, stir well, add ammonia solution, adjust the pH to alkaline, and obtain mixed solution 1; (2) Add the RFE molecular sieve to the mixed solution 1, adjust the pH value to alkaline, stir, filter, wash and dry to obtain Ni / RFE; (3) Dissolve the platinum precursor in water, stir well, add ammonia solution, adjust the pH to alkaline, and obtain mixed solution 2; (4) Add the Ni / RFE to the mixed solution 2, adjust the pH value to alkaline, stir, filter, wash, dry and calcin to obtain the product.

[0008] In some embodiments, in step (1), the nickel precursor is any one of nickel chloride, nickel nitrate, and hexaammine nickel chloride; and / or, the concentration of the mixed solution 1 is 1~3 mg / mL.

[0009] In some embodiments, in steps (1) and (3), the mass percentage of the ammonia solution is 25-28 wt.%; and / or, the alkalinity has a pH value of 8-11.

[0010] In some embodiments, in step (2), the RFE molecular sieve is ZSM-48 with a silicon-to-aluminum ratio of 50-200:1 (preferably 100:1); and / or, the mass ratio of nickel in the nickel precursor to the RFE molecular sieve is 0.5-1.5%.

[0011] In some embodiments, in steps (2) and (4), the pH adjustment is performed using an ammonia solution; and / or the alkalinity has a pH of 9 to 11.5; and / or the ammonia solution has a mass percentage of 25 to 28 wt.%.

[0012] In some embodiments, in step (2), the stirring time is 2-24 h; and / or the drying time is 80-120°C for 4-12 h.

[0013] In some embodiments, in step (3), the platinum precursor is any one of tetraammineplatinum acetate, chloroplatinic acid, and platinum nitrate; and / or, the mass ratio of platinum in the platinum precursor to the RFE molecular sieve is 0.003~0.6% (preferably 0.005%); and / or, the concentration of the mixed solution 2 is 0.002~0.4 mg / mL.

[0014] In some embodiments, in step (4), the stirring time is 2 to 24 h; and / or the drying time is 80 to 120°C for 2 to 4 h; and / or the calcination time is 300 to 500°C for 4 to 8 h.

[0015] The bimetallic Ni-Pt / RFE hydroisomer catalyst prepared by the above method is also within the scope of protection of this invention.

[0016] The application of the bimetallic Ni-Pt / RFE hydroisomerization catalyst in hydroisomerization catalysis is preferably in alkane hydroisomerization catalysis.

[0017] Beneficial effects:

[0018] (1) The Ni-Pt / RFE catalyst has a simple synthesis procedure and mild operating conditions. It can not only achieve the purpose of energy saving and emission reduction, but also realize the efficient isomerization of long straight-chain alkanes in oil products. Furthermore, it uses non-precious metals to replace precious metals, greatly reducing the amount of precious metals used and significantly reducing the cost of catalyst preparation. It also has the advantages of anti-sintering, not easy to deactivate, and simple operation procedure.

[0019] (2) The synergistic effect between Ni and Pt metal particles significantly improves the performance of Ni-Pt / FER catalyst. After introducing a small amount of Pt, the catalyst activity is significantly enhanced, and its performance is better than that of single Pt / FER catalyst; the isomerization conversion rate of n-dodecane is close to 90% within 60 minutes, showing high hydroisomerization reaction activity.

[0020] (3) The Ni-Pt / FER catalyst prepared by this method can reduce the Pt loading from 0.5 wt.% to 0.005 wt.% compared with the conventional synthesis method. At the same time, the original acidic center of the molecular sieve is completely preserved. The resulting product has a higher content of weak acid and a lower content of medium and strong acid. It can also effectively increase the content of L acid center and reduce the content of Brønsted acid. In the isomerization of long-chain alkane, this acid distribution is more conducive to the isomerization reaction and reduces cracking products. Attached Figure Description

[0021] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments, and the advantages of the present invention in the above and / or other aspects will become clearer.

[0022] Figure 1 The attached figure shows the XRD pattern of Ni-Pt 0.005% / RFE prepared in Example 1;

[0023] Figure 2 The attached figure shows the Ni-Pt 0.005% / RFE NH3-TPD prepared in Example 1;

[0024] Figure 3 The attached image shows the 200°C Py-FTIR of Ni-Pt 0.005% / RFE prepared in Example 1.

[0025] Figure 4The attached TEM image shows the Ni-Pt 0.005% / RFE prepared in Example 1.

[0026] Figure 5 The isomerization yield diagram shows the Ni-Pt 0.005% / RFE prepared in Example 1 and the Pt / RFE prepared in Comparative Example 1. Detailed Implementation

[0027] The present invention will be further described below with reference to the following embodiments. It should be understood that the following embodiments are for illustrative purposes only and are not intended to limit the present invention.

[0028] For any specific techniques or conditions not specified in the examples, the techniques or conditions described in the literature in this field, or the product instructions, shall be followed. All reagents or instruments used, unless otherwise specified, are conventional products that can be purchased from legitimate channels.

[0029] Source of raw materials or equipment: including raw material name, specifications, and manufacturer.

[0030]

[0031] Evaluation and analysis methods:

[0032] XRD measurements were performed on a Bruker diffractometer. A Cu target Kα light source (λ = 0.15432 nm), a graphite monochromator, a tube voltage of 40 kV, and a tube current of 40 mA were used. The XRD values ​​were measured between 5 and 55 nm. o The scanning speed within the interval is 10. o / min. Qualitative analysis was performed using JCPDS (Junior High-Pressure Cryometry Data Sheets).

[0033] NH3-TPD experiment: Acidity test was performed using the calcined catalyst. The catalyst was pressed into tablets under a pressure of 1.5-2.0 MPa in a dry state, sieved into 20-40 mesh particles, purged under a helium atmosphere, and adsorbed with 10% ammonia and helium at 120°C. The temperature was then raised to 550°C to investigate the content of different acid strengths.

[0034] Py-IR Experiment: Pyridine infrared (Py-IR) spectra were recorded using a Thermo Fisher Scientific NICOLET iS20 Fourier transform infrared spectrometer. The characteristic peak at 1545 cm⁻¹ corresponds to Brønsted acid, and the characteristic peak at 1455 cm⁻¹ corresponds to Lewis acid. Typically, total acid content is measured at 200°C, and the content of moderately strong acids is measured at 350°C.

[0035] Example 1

[0036] (1) At 25°C, 0.49 g of hexaammine nickel chloride was first dissolved in 180 mL of deionized water, and then 25~28 wt.% ammonia solution was added dropwise. After adjusting the pH value to 9, the mixture was stirred for 2 h to obtain mixed solution 1.

[0037] (2) Take 10 g of RFE molecular sieve (ZSM-48, Si / Al = 100) and disperse it in mixed solution 1. Then add 25~28 wt.% ammonia solution dropwise, adjust the pH value to 10, stir for 24 h, filter, wash, and dry at 90°C for 4 h to obtain Ni / RFE;

[0038] (3) At 25°C, 0.001 g of tetraammineplatinum acetate was first dissolved in 220 mL of deionized water, and then 25~28 wt.% ammonia solution was added dropwise. After adjusting the pH value to 9, the mixture was stirred for 1 h to obtain mixed solution 2.

[0039] (4) Disperse the Ni / RFE prepared in step (2) into mixed solution 2, then add 25~28 wt.% ammonia solution dropwise, adjust the pH value to 9, stir for 12 h, filter, wash, dry at 90°C for 3 h, and finally calcine at 400°C for 5 h to obtain Ni-Pt 0.005% / RFE.

[0040] 2.5 g of Ni-Pt 0.005% / RFE was loaded into a fixed-bed reactor, and hydrogen gas was introduced (50 mL / min). After reduction at 350 °C for 2 h, n-dodecane was pumped in at 0.111 mL / min, and the reaction was carried out at 320 °C for 2 h. After the reaction, the catalyst was dried, calcined, and recycled. The product was collected from the outlet, and the concentration of n-dodecane in the model oil was determined by liquid chromatography. The final conversion rate of n-dodecane was 92%, and the selectivity was 80%, achieving efficient hydroisomerization.

[0041] The Ni-Pt 0.005% / RFE catalyst prepared in Example 1 was subjected to XRD testing, and the results are as follows: Figure 1 As shown, the sample exhibits typical diffraction peaks at 2θ = 7.4°, 8.6°, 15°, 21°, 22.7°, and 31.2°, which are characteristic peaks of the RFE topology. No second-phase diffraction signal was detected in the spectrum, indicating the absence of significant amorphous impurities or other crystalline impurities in the catalyst. This result further suggests that the metallic material is uniformly distributed on the surface or within the pores of the RFE support.

[0042] The Ni-Pt 0.005% / RFE catalyst prepared in Example 1 was subjected to NH3-TPD and Py-FTIR tests, as follows: Figure 2As shown, the NH3-TPD curves of the catalyst all exhibit two characteristic desorption peaks, corresponding to the desorption behavior of NH3 adsorbed at acidic sites of different strengths: low temperature desorption peak: temperature range of 130°C~300°C, corresponding to the desorption of NH3 adsorbed at weakly acidic sites; high temperature desorption peak: temperature range of 340°C~500°C, corresponding to the desorption of NH3 adsorbed at moderately strong acidic sites.

[0043] like Figure 3 As shown, Py-FTIR is a classic technique for characterizing the acid type of catalysts. Its core advantage lies in its ability to effectively distinguish between Brønsted acids (B acids) and Lewis acids (L acids): by identifying the characteristic infrared absorption peaks generated after pyridine molecules bind to different acid sites (such as 1545 cm⁻¹ corresponding to B acids and 1455 cm⁻¹ corresponding to L acids), it is possible not only to clearly identify the presence of B and L acids in the catalyst, but also to obtain the relative proportion of the two acid sites through semi-quantitative calculations based on the peak areas of the characteristic peaks, providing a direct basis for analyzing the regulation of acid types by active metals.

[0044] These two experiments demonstrate a significant enhancement in the acidity of the catalyst, primarily through an increase in Lewis acid sites. The higher Lewis acid content facilitates the conversion of monobranched alkanes to multibranched alkanes during alkane isomerization, thereby endowing it with excellent performance characteristics for producing high-quality lubricating oil base oils.

[0045] TEM experiments were performed on the Ni-Pt 0.005% / RFE catalyst prepared in Example 1, as follows: Figure 4 As shown, the structure of the metal particles and molecular sieve on the catalyst surface can be clearly observed by transmission electron microscopy. It can be seen that each metal particle (the dot in the figure) is at a certain distance from other particles and is uniformly distributed on the surface of the molecular sieve.

[0046] Example 2

[0047] (1) At 25°C, 0.37 g of nickel chloride was first dissolved in 280 mL of deionized water, and then 25~28 wt.% ammonia solution was added dropwise. After adjusting the pH value to 10, the mixture was stirred for 1 h to obtain mixed solution 1.

[0048] (2) Take 15 g of RFE molecular sieve (ZSM-48, Si / Al = 100) and disperse it in mixed solution 1. Then add 25~28 wt.% ammonia solution dropwise, adjust the pH value to 10, stir for 12 h, filter, wash, and dry at 120°C for 4 h to obtain Ni / RFE;

[0049] (3) At 25°C, 0.001 g of tetraammineplatinum acetate was first dissolved in 180 mL of deionized water, and then 25-28 wt.% ammonia solution was added dropwise. After adjusting the pH value to 10, the mixture was stirred for 3 h to obtain mixed solution 2.

[0050] (4) Disperse the Ni / RFE prepared in step (2) into mixed solution 2, then add 25~28 wt.% ammonia solution dropwise, adjust the pH value to 10, stir for 24 h, filter, wash, dry at 110°C for 3 h, and finally calcine at 500°C for 4 h to obtain Ni-Pt / RFE.

[0051] 2.5 g of Ni-Pt / RFE was loaded into a fixed-bed reactor, and hydrogen gas was introduced (50 mL / min). After reduction at 350°C for 2 h, n-dodecane was pumped in at 0.111 mL / min, and the reaction was carried out at 320°C for 2 h. After the reaction, the catalyst was dried, calcined, and recycled. The product was collected from the outlet, and the concentration of n-dodecane in the model oil was determined by liquid chromatography. The final conversion rate of n-dodecane was 89%, and the selectivity was 80%, achieving efficient hydroisomerization.

[0052] Example 3

[0053] (1) At 25°C, 0.31 g of nickel nitrate was first dissolved in 110 mL of deionized water, and then 25~28 wt.% ammonia solution was added dropwise. After adjusting the pH value to 9, the mixture was stirred for 1 h to obtain mixed solution 1.

[0054] (2) Take 5 g of RFE molecular sieve (ZSM-48, Si / Al = 100) and disperse it in mixed solution 1. Then add 25~28 wt.% ammonia solution dropwise, adjust the pH value to 11.5, stir for 8 h, filter, wash, and dry at 100°C for 4 h to obtain Ni / RFE;

[0055] (3) At 25°C, 0.021 g of platinum nitrate was first dissolved in 110 mL of deionized water, and then 25~28 wt.% ammonia solution was added dropwise. After adjusting the pH value to 9, the mixture was stirred for 3 h to obtain mixed solution 2.

[0056] (4) Disperse the Ni / RFE prepared in step (2) into mixed solution 2, then add 25~28 wt.% ammonia solution dropwise, adjust the pH value to 11.5, stir for 8 h, filter, wash, dry at 100°C for 3 h, and finally calcine at 300°C for 8 h to obtain Ni-Pt / RFE.

[0057] 2.5 g of Ni-Pt / RFE was loaded into a fixed-bed reactor, and hydrogen gas was introduced (50 mL / min). After reduction at 350°C for 2 h, n-dodecane was pumped in at 0.111 mL / min, and the reaction was carried out at 320°C for 2 h. After the reaction, the catalyst was dried, calcined, and recycled. The product was collected from the outlet, and the concentration of n-dodecane in the model oil was determined by liquid chromatography. The final conversion rate of n-dodecane was 93%, and the selectivity was 75%, achieving efficient hydroisomerization.

[0058] Example 4

[0059] (1) At 25°C, 0.134 g of nickel nitrate was first dissolved in 70 mL of deionized water, and then 25~28 wt.% ammonia solution was added dropwise. After adjusting the pH value to 10, the mixture was stirred for 1 h to obtain mixed solution 1.

[0060] (2) Take 2.5 g of RFE molecular sieve (ZSM-48, Si / Al = 100) and disperse it in mixed solution 1. Then add 25~28 wt.% ammonia solution dropwise, adjust the pH value to 10.5, stir for 16 h, filter, wash, and dry at 120°C for 4 h to obtain Ni / RFE;

[0061] (3) At 25°C, 0.025 g of tetraammineplatinum acetate was first dissolved in 70 mL of deionized water, and then 25~28 wt.% ammonia solution was added dropwise. After adjusting the pH value to 10, the mixture was stirred for 2 h to obtain mixed solution 2.

[0062] (4) Disperse the Ni / RFE prepared in step (2) into mixed solution 2, then add 25~28 wt.% ammonia solution dropwise, adjust the pH value to 10.5, stir for 16 h, filter, wash, dry at 120°C for 3 h, and finally calcine at 300°C for 4 h to obtain Ni-Pt / RFE.

[0063] 2.5 g of Ni-Pt / RFE was loaded into a fixed-bed reactor, and hydrogen gas was introduced (50 mL / min). After reduction at 350°C for 2 h, n-dodecane was pumped in at 0.111 mL / min, and the reaction was carried out at 320°C for 2 h. After the reaction, the catalyst was dried, calcined, and recycled. The product was collected from the outlet, and the concentration of n-dodecane in the model oil was determined by liquid chromatography. The final conversion rate of n-dodecane was 92%, and the selectivity was 78%, achieving efficient hydroisomerization.

[0064] Example 5

[0065] (1) At 25°C, 0.740 g of hexaammine nickel chloride was first dissolved in 280 mL of deionized water, and then 25~28 wt.% ammonia solution was added dropwise. After adjusting the pH value to 11, the mixture was stirred for 1 h to obtain mixed solution 1.

[0066] (2) Take 15 g of RFE molecular sieve (ZSM-48, Si / Al = 100) and disperse it in mixed solution 1. Then add 25~28 wt.% ammonia solution dropwise, adjust the pH value to 11.5, stir for 12 h, filter, wash, and dry at 120°C for 4 h to obtain Ni / RFE;

[0067] (3) At 25°C, 0.001 g of tetraammineplatinum acetate was first dissolved in 280 mL of deionized water, and then 25~28 wt.% ammonia solution was added dropwise. After adjusting the pH value to 11, the mixture was stirred for 2 h to obtain mixed solution 2.

[0068] (4) Disperse the Ni / RFE prepared in step (2) into mixed solution 2, then add 25~28 wt.% ammonia solution dropwise, adjust the pH value to 11.5, stir for 24 h, filter, wash, dry at 120°C for 3 h, and finally calcine at 300°C for 4 h to obtain Ni-Pt / RFE.

[0069] 2.5 g of Ni-Pt / RFE was loaded into a fixed-bed reactor, and hydrogen gas was introduced (50 mL / min). After reduction at 350°C for 2 h, n-dodecane was pumped in at 0.111 mL / min, and the reaction was carried out at 320°C for 2 h. After the reaction, the catalyst was dried, calcined, and recycled. The product was collected from the outlet, and the concentration of n-dodecane in the model oil was determined by liquid chromatography. The final conversion rate of n-dodecane was 92%, and the selectivity was 80%, achieving efficient hydroisomerization.

[0070] Comparative Example 1

[0071] At 25°C, 0.07365 g of tetraammineplatinum acetate was first dissolved in 190 mL of deionized water, and then 25-28 wt.% ammonia solution was added dropwise. After adjusting the pH to 10, the mixture was stirred for 1 h to obtain mixed solution 1.

[0072] 7.5 g of RFE molecular sieve (ZSM-48, Si / Al = 100) was dispersed in mixed solution 1, and then ammonia solution was added dropwise to adjust the pH to 10.5. After stirring for 16 h, the solution was filtered, washed, dried at 120°C for 3 h, and finally calcined at 400°C for 6 h to obtain Pt / RFE.

[0073] 2.5 g of Pt / RFE was loaded into a fixed-bed reactor, and hydrogen gas was introduced (50 mL / min). After reduction at 350°C for 2 h, n-dodecane was pumped in at 0.111 mL / min, and the reaction was carried out at 320°C for 2 h. After the reaction, the catalyst was dried, calcined, and recycled. The product was discharged from the outlet, and the concentration of n-dodecane in the model oil was determined by liquid chromatography. Figure 5 As shown, the mass ratio of Pt to support in Pt / RFE is 0.5%. Before 292.5°C, the isomerization yield of the Pt / RFE group is higher than that of the Ni-Pt 0.005% / RFE group. However, after 292.5°C, the isomerization yield of the Ni-Pt 0.005% / RFE group is even higher, and the amount of precious metal Pt used is less, at 0.005%.

[0074] This invention provides a bimetallic Ni-Pt / RFE hydroisomerization catalyst, its preparation method, and its application. Many methods and approaches exist for implementing this technical solution; the above description is merely a preferred embodiment. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of this invention, and these improvements and modifications should also be considered within the scope of protection of this invention. All components not explicitly stated in this embodiment can be implemented using existing technologies.

Claims

1. A method for preparing a bimetallic Ni-Pt / RFE hydroisomerization catalyst, characterized in that, Includes the following steps: (1) Dissolve the nickel precursor in water, stir well, add ammonia solution, adjust the pH to alkaline, and obtain mixed solution 1; (2) Add the RFE molecular sieve to the mixed solution 1, adjust the pH value to alkaline, stir, filter, wash and dry to obtain Ni / RFE; (3) Dissolve the platinum precursor in water, stir well, add ammonia solution, adjust the pH to alkaline, and obtain mixed solution 2; (4) Add the Ni / RFE to the mixed solution 2, adjust the pH value to alkaline, stir, filter, wash, dry and calcin to obtain the product.

2. The preparation method according to claim 1, characterized in that, In step (1), the nickel precursor is any one of nickel chloride, nickel nitrate, and hexaammine nickel chloride; and / or, the concentration of the mixed solution 1 is 1~3 mg / mL.

3. The preparation method according to claim 1, characterized in that, In steps (1) and (3), the mass percentage of the ammonia solution is 25-28 wt.%; and / or the alkalinity is such that the pH value is 8-11.

4. The preparation method according to claim 1, characterized in that, In step (2), the RFE molecular sieve is ZSM-48 with a silicon-to-aluminum ratio of 50-200:1; and / or, the mass ratio of nickel in the nickel precursor to the RFE molecular sieve is 0.5-1.5%.

5. The preparation method according to claim 1, characterized in that, In steps (2) and (4), the pH adjustment is performed by using an ammonia solution; and / or the alkalinity is such that the pH value is 9 to 11.5; and / or the mass percentage of the ammonia solution is 25 to 28 wt.%.

6. The preparation method according to claim 1, characterized in that, In step (2), the stirring time is 2-24 hours; and / or the drying time is 80-120°C for 4-12 hours.

7. The preparation method according to claim 1, characterized in that, In step (3), the platinum precursor is any one of tetraammineplatinum acetate, chloroplatinic acid, and platinum nitrate; and / or, the mass ratio of platinum in the platinum precursor to the RFE molecular sieve is 0.003~0.6%; and / or, the concentration of the mixed solution 2 is 0.002~0.4 mg / mL.

8. The preparation method according to claim 1, characterized in that, In step (4), the stirring time is 2-24 hours; and / or the drying time is 80-120°C for 2-4 hours; and / or the calcination time is 300-500°C for 4-8 hours.

9. The bimetallic Ni-Pt / RFE hydroisomer catalyst prepared by the preparation method according to any one of claims 1 to 8.

10. The application of the bimetallic Ni-Pt / RFE hydroisomerization catalyst according to claim 9 in hydroisomerization catalytic reactions.

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