CN111218311A

CN111218311A - Method for preparing biodiesel by photocatalysis biological platform compound

Info

Publication number: CN111218311A
Application number: CN201811411728.8A
Authority: CN
Inventors: 王峰; 罗能超; 侯婷婷; 张健
Original assignee: Dalian Institute of Chemical Physics of CAS
Current assignee: Dalian Institute of Chemical Physics of CAS
Priority date: 2018-11-25
Filing date: 2018-11-25
Publication date: 2020-06-02
Anticipated expiration: 2038-11-25
Also published as: CN111218311B

Abstract

The invention relates to a method for preparing biodiesel by a photocatalytic biological platform compound. The method adopts lignocellulose downstream products 2-methylfuran and 2, 5-dimethylfuran as raw materials, directly prepares diesel precursor components such as C10-C12, C15-C18 and C20 under the action of a solid photocatalyst, and then obtains the biodiesel by low-temperature hydrodeoxygenation (<250 ℃) under the solid hydrogenation-acid-base bifunctional catalyst. Mixing 2-methylfuran, 2, 5-dimethylfuran or a mixture thereof, a catalyst and an acetonitrile solvent, putting the mixture into a pressure container, replacing the mixture with inert gas, stirring the mixture under normal temperature illumination, wherein the reaction time is longer than 1 hour, and separating the catalyst from a reaction system after the reaction. The unreacted starting material is recovered by primary distillation. The product is reduced to obtain the biodiesel under the condition of hydrogen by a hydrogenation-acid-base bifunctional catalyst, the catalyst can be recycled for many times, and the selectivity of the biodiesel can reach 99 percent at most.

Description

Method for preparing biodiesel by photocatalysis biological platform compound

Technical Field

The invention relates to a method for preparing biodiesel by a photocatalytic biological platform compound, in particular to a series reaction process that 2-methylfuran or 2, 5-dimethylfuran is directly dehydrocoupled to diesel precursor components such as C10-C12, C15-C18 and C20 by photocatalysis, and then is hydrodeoxygenated to obtain straight chain and branched chain alkane.

Background

Diesel is a very important energy strategic material, and the production thereof is currently very dependent on petrochemical resources. Because of the shortage of oil in China, the production of diesel oil is extremely dependent on import. There would be significant market value and strategic needs if high quality diesel fuel, particularly special purpose diesel fuel, could be produced from other renewable sources. The diesel oil is mainly a mixture of alkane, cyclane, alkene and arene with carbon chain length of C10-C22. The diesel oil is divided into light diesel oil (180-370 ℃) and heavy diesel oil (350-410 ℃). Compared with gasoline, diesel oil has high energy density and high fuel consumption rate. Therefore, the power is larger, and the power source is a power source for large vehicles, railway locomotives, ships and the like. With the increasing importance of the country on environmental protection, higher requirements are put forward on the quality of diesel oil. Higher requirements are also put on the cetane number of the diesel oil and the content of polycyclic aromatic hydrocarbon in the diesel oil.

At present, there are many international methods for producing biodiesel, but most biodiesel has low heat value and high freezing point due to single component and high oxygen content (CN 102864024A). Therefore, most of the produced biodiesel can only be used as an additive, namely the biodiesel is required to have the highest addition ratio. In addition, the addition of traditional biodiesel often results in the performance degradation of crude diesel (CN 1944582A). Therefore, methods for preparing high-quality biodiesel from lignocellulose downstream products such as furfural, 5-hydroxymethylfurfural, levulinic acid, 2-methylfuran, 2, 5-dimethylfuran and the like are developed at home and abroad subsequently (Science,2005,308, 1446-1450). The diesel oil is prepared by first adjusting the length of a carbon chain to the carbon number of diesel oil through a carbon-carbon coupling reaction, and then hydrodeoxygenating the diesel oil precursor by using a hydrodeoxygenation catalyst. The biodiesel has high cetane number, low oxygen content and high alkane ratio. However, in the method, carbon-carbon coupling generally adopts a homogeneous acid-base catalyst (Energy environ. sci.,2012,5, 6328-6344) with better selectivity, and the catalytic reaction can be realized at a lower temperature. The use of heterogeneous acid-base catalysts tends to require higher reaction temperatures and lower carbon yields (CN 104971775A). Whereas the second step, i.e. the hydrodeoxygenation step, often requires higher reaction temperatures (greater than 300 ℃) to be achieved (Energy environ. sci.,2012,5, 6328-6344). Therefore, it is necessary to realize the process by adopting a lower method and sustainable energy, and further improve the quality of the diesel oil.

Both 2-methylfuran and 2, 5-dimethylfuran are downstream products of lignocellulosic conversion. Hydrolysis of lignocellulose is carried out to obtain monosaccharide, and isomerization and dehydration are carried out to obtain 5-hydroxymethylfurfural and furfural. The 5-hydroxymethyl furfural and the furfural can obtain 2, 5-dimethylfuran and 2-methylfuran with high selectivity under the action of a solid catalyst. Particularly, the process of producing furfural from straw and other lignocellulose resources is industrialized, and at present, China is one of the largest furfural producing countries. While industrial research on 2, 5-dimethylfuran is under development, it is believed that it will be realized soon. Therefore, the method for producing high-quality diesel oil by using 2-methylfuran and 2, 5-dimethylfuran as starting raw materials has certain market value. Light energy is a very clean, sustainable energy source that, if used directly to drive the process at room temperature, would make biodiesel production "zero-polluting".

Disclosure of Invention

The invention aims to utilize sustainable light energy, prepare high-quality diesel oil with high efficiency and low cost under mild conditions (normal temperature and pressure), and greatly adopt a sustainable green method, so that the catalyst is easy to separate and can be recycled for many times.

The diesel oil related to the invention is prepared by the following scheme: mixing one or two of 2-methylfuran or 2, 5-dimethylfuran, a solid photocatalyst and an acetonitrile solvent, putting the mixture into a quartz glass tube under the protection of inert gas, stirring and reacting at normal temperature under illumination for longer than 1 hour, wherein the reaction product is a dimeric, trimeric and small amount of tetrameric compound. The photocatalyst is then filtered and Pd/N is added₂O₅And Yb (CF)₃SO₃)₃Catalyst and cyclohexane solvent, then reducing under the condition of hydrogen, evaporating and recovering the cyclohexane solvent, and obtaining the diesel oil.

Wherein the 2-methylfuran or 2, 5-dimethylThe volume concentration of the furan in the initial reaction system is 1-100 vol%; the light source is one or more than two of LEDs; the photocatalyst (M-Zn)_xIn₂S_3+xY) of a supported metal M of Ru, Pd, Pt, Ni or Mo, x being 0.05 to 6, the amount of doping y being 0 to 5 mol%, the amount being 0.1 to 100g (L substrate)^-1(ii) a The reaction time is 12-24 h.

The hydrogenation-acid-base bifunctional catalyst is Pd/Nb₂O₅-m, wherein m has a value of 0.1 to 10 wt.% and is present in an amount of 0.001 to 0.5kg (kg substrate)^-1(ii) a Acid catalyst Yb (CF)₃SO₃)₃The dosage is 0-0.5 kg (kg substrate)^-1(ii) a The reaction temperature program is 100-180 ℃ and then 180-250 ℃; the time of the two temperature procedures is 0-10 hours and 0-20 hours respectively.

Preferably, the method comprises the following steps: wherein the volume concentration of the 2-methylfuran or the 2, 5-dimethylfuran in the initial reaction system is 10-100 vol%; the light source is one or more than two of a xenon lamp or an LED; the photocatalyst (M-Zn)_xIn₂S_3+x-y) of a supported metal M of Ru, Pd or Mo, x being 0.5 to 3, the doping amount y being 0 to 1.5 mol%, the amount being 1 to 40g (L substrate)^-1(ii) a The reaction time is 5-50 h.

The hydrogenation-acid-base bifunctional catalyst is Pd/Nb₂O₅-m, wherein m has a value of 0.5 to 5 wt.% and is present in an amount of 0.02 to 0.3kg (kg substrate)^-1(ii) a Acid catalyst Yb (CF)₃SO₃)₃The dosage is 0-0.1 kg (kg substrate)^-1(ii) a The reaction temperature program is 110-150 ℃ and then 200-240 ℃; the time of the two temperature procedures is 1-8 hours and 2-12 hours respectively.

The best is as follows: wherein the volume concentration of the 2-methylfuran or the 2, 5-dimethylfuran in the initial reaction system is 30-80 vol%; the light source is an LED; the photocatalyst (M-Zn)_xIn₂S_3+x-y) of a supported metal M of Ru, x of 1 to 2, doping amount y of 0.5 to 0.7 mol%, in an amount of 10 to 20g (L substrate)^-1(ii) a The reaction time is 12-24 h.

The hydrogenation-acid-base bifunctional catalyst is Pd/Nb₂O₅-m, wherein m has a value of 1.5 to 3 wt.% and is present in an amount of 0.05 to 0.1kg (kg substrate)^-1(ii) a Acid catalyst Yb (CF)₃SO₃)₃The dosage is 0-0.01 kg (kg substrate)^-1(ii) a The reaction temperature program is 120-135 ℃ and then 210-230 ℃; the time of the two temperature procedures is 3-5 hours and 3-8 hours respectively.

The anaerobic dehydrocoupling of 2, 5-dimethylfuran and 2-methylfuran to 1,2- (2- (5-methylfuryl)) ethane and 1,2- (2-furyl) ethane is an endothermic process that is difficult to achieve using thermocatalytic methods. In addition, high temperature aqueous systems are prone to ring-opening monomers or uncontrollable polymerization to high polymers and do not yield diesel components. This process requires the simultaneous activation of the C-H bond at the benzylic position as well as the hydrogen-evolving active site. Very high demands are therefore placed on the catalyst. This process can be well achieved using a photocatalytic approach. It is critical to select the appropriate photocatalyst and its composition. The preferred catalyst is ternary sulfide Ru-Zn_xIn₂S_3+x-y; in the preferable catalyst composition, the value of x is 1 to 2, the doping amount y is 0.5 to 0.7 mol%, and the dosage is 10 to 20g (L substrate)^-1。

In addition, in the step of hydrodeoxygenation, the diesel oil precursor is subjected to direct high-temperature hydrodeoxygenation reaction, so that furan rings can easily cause severe polymerization reaction under the catalysis of a high-temperature acid-base catalytic center, and therefore, generally, hydrogenation is carried out at a preferred low temperature (120-135 ℃) to obtain a de-furanized intermediate, and then a hydrocarbon product is obtained under the sequential/synergistic action of hydrogenation-acid-base catalytic center at a high temperature. For some diesel oil precursors needing stronger acid-base catalytic conversion, a small amount of Yb (CF) needs to be additionally added₃SO₃)₃To enhance the catalytic dehydration performance and obtain high hydrocarbon selectivity.

Like other photocatalytic reactions, the greater the light intensity of the light source, the faster the reaction rate. The catalyst activity is reduced due to strong adsorption of reaction products on the catalyst surface. The preferred reaction time is therefore 12-24h, which allows the desired product to be obtained in higher quantum yields (for example 2, 5-dimethylfuran can give an apparent quantum yield of up to 45.6% over the preferred catalyst, suitable for industrial exploration). The unreacted raw materials have low boiling points and can be recovered by distillation at a lower temperature. The reaction can be promoted by the oxidation of C-H bond promoted by the solvent action of the inert acetonitrile solvent, so that the fastest reaction rate of the diesel precursor is obtained.

Compared with the existing method for preparing diesel oil, the method has the following advantages:

1. the reaction process is green and clean, and high-quality diesel oil can be continuously obtained by using raw materials from lignocellulose;

2. the operation process is simple and safe, and raw materials and catalysts which are dangerous, highly toxic, environment-polluting, strongly corrosive and harmful to human bodies are avoided;

3. the catalyst is simple to prepare, can be separated from a reaction system through the existing chemical unit operation, and can remove a diesel oil precursor adsorbed on the catalyst by simple washing with a low-boiling-point dichloromethane solvent, and the washed dichloromethane can be recovered;

4. can co-produce H₂And a diesel precursor, which can be carried out at normal temperature without heating, and can produce a byproduct H₂Preferably without H₂S and formation of sulfur-containing organic compounds, H₂Can be used for hydrogen fuel cell vehicles or the next step of hydrodeoxygenation;

5. the obtained diesel oil has high quality. The obtained diesel oil contains more carbon chain lengths with different lengths and has higher branched hydrocarbon content.

Drawings

FIGS. 1(a) and (b) are gas chromatograms of example 1 and example 8, respectively;

figure 2 is a diagram of the main diesel precursor components in example 1.

Detailed Description

In order to further explain the present invention in detail, several embodiments are given below. The method comprises the steps of obtaining a diesel precursor through photocatalytic C-C coupling in the embodiments 1-12, wherein the embodiments 13-16 are hydrodeoxygenation embodiments, and the diesel precursor in the embodiment 11 is used as a raw material. The present invention is not limited to these examples.

Example 1

In a 5mL quartz glass reaction tube, 0.5mL of 2, 5-dimethylfuran and 0.5mL of acetonitrile were added, and 10mg of Ru-ZnIn was weighed₂S₄-0.5 catalyzing the reaction, replacing the reaction tube with argon gas and sealing, illuminating by a 9W LED at normal temperature for 12h, and detecting the product by chromatography after the reaction is finished to obtain a dimer, a trimer and a small amount of tetramer. The yield of diesel precursor was 0.165 g.

Example 2

In a 5mL quartz glass reaction tube, 0.5mL of 2, 5-dimethylfuran and 0.5mL of acetonitrile were added, and 10mg of ZnIn was weighed₂S₄Catalyzing the reaction, replacing the reaction tube with argon gas, sealing, illuminating by a 9W LED at normal temperature for 12h, and detecting the product by chromatography after the reaction is finished, wherein the mass spectrogram of the product is consistent with the standard mass spectrogram. The yield of the diesel precursor is 0.057 g.

Example 3

In a 5mL quartz glass reaction tube, 0.5mL of 2, 5-dimethylfuran and 0.5mL of acetonitrile were added, and 10mg of Ru-Zn was weighed₂In₂S₅-0.5 catalyzing the reaction, replacing the reaction tube with argon gas, sealing, irradiating for 12h at normal temperature by 9WLED, and detecting the product by chromatography after the reaction is finished, wherein the mass spectrum of the product is consistent with that of the standard mass spectrum. The yield of diesel precursor was 0.322 g.

Example 4

Respectively adding 10mL of 2, 5-dimethylfuran and 10mL of acetonitrile into a 200mL quartz glass reaction kettle, and weighing 200mg of Ru-ZnIn₂S₄And (3) catalyzing the reaction, replacing the reaction kettle with argon gas, sealing, illuminating by a 86W LED at normal temperature for 48 hours, and detecting a product by chromatography after the reaction is finished, wherein a mass spectrogram of the product is consistent with a standard mass spectrogram. The yield of diesel precursor was 2.52 g.

Example 5

In a 200mL quartz glass reaction vessel, 10mL 2, 5-dimethylfuran and 10mL acetonitrile are respectively added, and 200mg ZnIn is weighed₂S₄Catalyzing the reaction, replacing the reaction tube with argon gas, sealing, illuminating by a 86W LED for 48h at normal temperature, and detecting the product by chromatography after the reaction is finished, wherein the mass spectrogram of the product is consistent with the standard mass spectrogram. The yield of the diesel precursor is 1.02 g.

Example 6

In a 200mL quartz glass reaction vessel, 10mL 2, 5-dimethylfuran and 10mL acetonitrile are respectively added, and 200mg Ru-Zn is weighed₂In₂S₅And (3) catalyzing the reaction, replacing the reaction tube with argon gas, sealing, illuminating by a 86W LED at normal temperature for 48 hours, and detecting a product by chromatography after the reaction is finished, wherein a mass spectrogram of the product is consistent with a standard mass spectrogram. The yield of the diesel precursor is 6.02 g.

Example 7

In a 5mL quartz glass reaction tube, 0.5mL of 2-methylfuran and 0.5mL of acetonitrile were added, and 10mg of ZnIn was weighed₂S₄Catalyzing the reaction, replacing the reaction tube with argon gas, sealing, illuminating by a 9W LED at normal temperature for 12h, and detecting the product by chromatography after the reaction is finished, wherein the mass spectrogram of the product is consistent with the standard mass spectrogram. The yield of the diesel precursor is 0.011 g.

Example 8

0.5mL of 2-methylfuran and 0.5mL of acetonitrile were added to a 5mL quartz glass reaction tube, and 10mgRu-ZnIn was weighed₂S₄And (3) catalyzing the reaction, replacing the reaction tube with argon gas, sealing, illuminating by a 9W LED at normal temperature for 12 hours, and detecting a product by chromatography after the reaction is finished, wherein a mass spectrogram of the product is consistent with a standard mass spectrogram. The yield of the diesel precursor is 0.027 g.

Example 9

0.5mL of 2-methylfuran and 0.5mL of acetonitrile were added to a 5mL quartz glass reaction tube, and 10mgRu-Zn was weighed₂In₂S₅-0.5 catalyzing the reaction, replacing the reaction tube with argon gas, sealing, irradiating for 12h at normal temperature by 9WLED, and detecting the product by chromatography after the reaction is finished, wherein the mass spectrum of the product is consistent with that of the standard mass spectrum. The diesel precursor yield was 0.060 g.

Example 10

Respectively adding 10mL of 2-methylfuran and 10mL of acetonitrile into a 200mL quartz glass reaction kettle, and weighing 200mgRu-ZnIn₂S₄And (3) catalyzing the reaction, replacing the reaction tube with argon gas, sealing, illuminating by a 86W LED at normal temperature for 48 hours, and detecting a product by chromatography after the reaction is finished, wherein a mass spectrogram of the product is consistent with a standard mass spectrogram. The yield of diesel precursor was 0.512 g.

Example 11

In a 200mL quartz glass reaction vessel, 5mL of 2, 5-dimethylfuran, 15mL of 2-methylfuran and 10mL of acetonitrile were added, 200mg of Ru-ZnIn was weighed₂S₄-0.5 catalyzing the reaction, replacing the reaction tube with argon gas, sealing, illuminating for 48h at normal temperature with 86WLED, and detecting the product by chromatography after the reaction is finished, wherein the mass spectrum of the product is consistent with that of the standard mass spectrum. The yield of diesel precursor was 1.218 g.

Example 12

In a 200mL quartz glass reaction vessel, 5mL of 2, 5-dimethylfuran, 15mL of 2-methylfuran and 10mL of acetonitrile were added, respectively, and 200mg of Pd-ZnIn was weighed₂S₄And (3) catalyzing the reaction, replacing the reaction tube with argon gas, sealing, illuminating for 48 hours at normal temperature by 86WLED, and detecting a product by chromatography after the reaction is finished, wherein a mass spectrogram of the product is consistent with a standard mass spectrogram. The yield of the diesel precursor is 0.912 g.

Example 13

50mg of the diesel precursor prepared in example 1 was added to a 25ml Teflon lined reactor and 10mg of Pd/N was weighed₂O₅Catalyzing the reaction by 2 wt%, adding 3ml of cyclohexane as a solvent, replacing the reaction kettle for 3 times by argon, then replacing the reaction kettle for 3 times by 2.0MPa hydrogen, finally filling 2.0MPa hydrogen, sealing the reaction kettle, and heating to 120 ℃ for reaction for 3 hours; and then reacted at 210 ℃ for 6 h. The diesel oil component in the product was analyzed using n-tetradecane as an internal standard. After the reaction, the corresponding alkane component is obtained, and the alkane yield is 91%.

Example 14

50mg of the diesel precursor prepared in example 2 was added to a 25ml Teflon lined reactor and 20mg of Pd/N was weighed₂O₅Catalyzing the reaction by 2 wt%, adding 3ml of cyclohexane as a solvent, replacing the reaction kettle for 3 times by argon, then replacing the reaction kettle for 3 times by 3.0MPa hydrogen, finally filling 3.0MPa hydrogen, sealing the reaction kettle, and heating to 120 ℃ for reaction for 3 hours; and then reacted at 210 ℃ for 8 h. The diesel oil component in the product was analyzed using n-tetradecane as an internal standard. After the reaction, the corresponding alkane component is obtained, and the alkane yield is 99%.

Example 15

In a 25ml polytetrafluoroethylene lining reaction kettleRespectively adding 50mg of diesel oil precursor, and weighing 10mg Pd/N₂O₅Catalyzing the reaction by-2 wt%, adding 3ml of cyclohexane as a solvent, replacing the reaction kettle for 3 times by argon, then replacing the reaction kettle for 3 times by 3.0MPa hydrogen, finally filling 3.0MPa hydrogen, sealing the reaction kettle, and reacting for 6 hours at 210 ℃. The diesel oil component in the product was analyzed using n-tetradecane as an internal standard. After the reaction, the corresponding alkane component is obtained, and the alkane yield is 10%.

Example 16

100mg of the diesel precursor prepared in example 3 was added to a 25ml Teflon lined reactor and 10mg of Pd/N was weighed₂O₅Catalyzing the reaction by 2 wt%, adding 3ml of cyclohexane as a solvent, replacing the reaction kettle for 3 times by argon, then replacing the reaction kettle for 3 times by 3.0MPa hydrogen, finally filling 3.0MPa hydrogen, sealing the reaction kettle, and heating to 120 ℃ for reaction for 3 hours; and then reacted at 210 ℃ for 8 h. The diesel oil component in the product was analyzed using n-tetradecane as an internal standard. After the reaction, the corresponding alkane component is obtained, and the alkane yield is 98%.

Comparative example 1: CdS as catalyst

Respectively adding 0.5mL of 2, 5-dimethylfuran and 0.5mL of acetonitrile into a 5mL quartz glass reaction tube, weighing 10mg of CdS to catalyze the reaction, replacing the reaction tube with argon gas, sealing, illuminating by a 9W LED at normal temperature for 12h, and after the reaction is finished, detecting the product by chromatography, wherein the mass spectrogram of the product is consistent with the standard mass spectrogram. The yield of diesel precursor is 0.006 g.

Comparative example 2: taking Ni/CdS-2 wt% as catalyst

Respectively adding 0.5mL of 2, 5-dimethylfuran and 0.5mL of acetonitrile into a 5mL quartz glass reaction tube, weighing 10mg of Ni/CdS-2 wt% to catalyze the reaction, replacing the reaction tube with argon gas, sealing, illuminating by a 9W LED at normal temperature for 12h, and detecting the product by chromatography after the reaction is finished, wherein the mass spectrum of the product is consistent with that of a standard mass spectrum. The yield of the diesel precursor is 0.025 g.

Comparative example 3: in is formed by₂S₃As a catalyst

In a 5mL quartz glass reaction tube, 0.5mL of 2, 5-dimethylfuran and 0.5mL of acetonitrile were added, and 10mg of In was weighed₂S₃Catalyzing the reactionAnd replacing the reaction tube with argon gas, sealing, irradiating by a 9W LED at normal temperature for 12h, and detecting the product by chromatography after the reaction is finished, wherein the mass spectrogram of the product is consistent with the standard mass spectrogram. The yield of the diesel precursor is 0.001 g.

Claims

1. A method for preparing biodiesel by photocatalysis biological platform compounds is characterized by comprising the following steps:

the method comprises the following steps:

adding one or two of 2-methylfuran or 2, 5-dimethylfuran into a pressure vessel, and adding M-Zn_xIn₂S_3+xReplacing gas in the system with inert atmosphere gas (such as Ar) with the y photocatalyst with or without adding a solvent, and then performing illumination and stirring reaction at normal temperature for more than or equal to 1 hour to obtain a diesel precursor; wherein M is Ru, Pd, Pt, Ni or Mo, x is 0.05-6, and the doping amount y of M is 0-5 mol% of the molar amount of indium in the photocatalyst; filtering out the catalyst after the reaction, and recovering unreacted raw materials through reduced pressure distillation to obtain a diesel precursor;

diesel oil precursor and Pd/Nb₂O₅M, with or without addition of Yb (CF)₃SO₃)₃Adding catalyst and cyclohexane into reactor, filling H₂Reacting to obtain diesel oil; wherein the Pd loading m is Nb₂O₅0.1 to 10 wt% of the mass.

2. The method of claim 1, wherein: after the reaction, the catalyst is filtered out for recycling, and the diesel oil can be obtained by distilling the filtrate.

3. The method of claim 1, wherein:

wherein the reaction substrate is one or two of 2-methylfuran or 2, 5-dimethylfuran.

4. The method of claim 1, wherein:

the total volume concentration of the 2-methylfuran and/or the 2, 5-dimethylfuran in the initial reaction system is 1-100 vol%, preferably the volume concentration in the initial reaction system is 10-100 vol%, and more preferably the volume concentration in the initial reaction system is 30-80 vol%;

the photocatalyst (M-Zn)_xIn₂S_3+x-y) in an amount of 0.1 to 100g (L substrate)^-1。

5. The method according to claim 1 or 4, characterized in that:

the reaction time is 1-100 h, preferably 5-50 h, and more preferably 12-24 h;

preferably the photocatalyst (M-Zn)_xIn₂S_3+x-y) of a supported metal M of Ru, Pd or Mo, x being 0.5 to 3, the doping amount y being 0 to 1.5 mol%, the amount being 1 to 40g (L substrate)^-1(ii) a More preferably a photocatalyst (M-Zn)_xIn₂S_3+x-y) of a supported metal M of Ru, x of 1 to 2, doping amount y of 0.5 to 0.7 mol%, in an amount of 10 to 20g (L substrate)^-1。

6. The method of claim 1, wherein:

the light source is one or more of a xenon lamp, a high-pressure mercury lamp, an LED lamp or sunlight, preferably one or two of the xenon lamp or the LED, and more preferably the light source is the LED.

7. The method of claim 1, wherein:

the hydrogenation-acid-base bifunctional catalyst is Pd/Nb₂O₅-m, wherein m has a value of 0.1 to 10 wt.% and is present in an amount of 0.001 to 0.5kg (kg substrate)^-1(ii) a Acid catalyst Yb (CF)₃SO₃)₃The dosage is 0-0.5 kg (kg substrate)^-1；

The reaction is divided into two temperature procedures, wherein the two temperature procedures are that the temperature is kept at 100-180 ℃ firstly, and then kept at 180-250 ℃;

the time of the two temperature procedures is 1-10 hours and 1-20 hours respectively.

8. The method of claim 1 or 7, wherein:

the hydrogenation-acid-base bifunctional catalyst is Pd/Nb₂O₅-m, wherein m has a value of 0.5 to 5 wt.% and is present in an amount of 0.02 to 0.3kg (kg substrate)^-1(ii) a Acid catalyst Yb (CF)₃SO₃)₃The dosage is 0-0.1 kg (kg substrate)^-1；

The reaction is divided into two temperature programs, wherein the two temperature programs are 110-150 ℃ and then the temperature is increased to 200-240 ℃;

the time of the two temperature procedures is 1-8 hours and 2-12 hours respectively.

9. The method of claim 1 or 7, wherein:

the hydrogenation-acid-base bifunctional catalyst is Pd/Nb₂O₅-m, wherein m has a value of 1.5 to 3 wt.% and is present in an amount of 0.05 to 0.1kg (kg substrate)^-1(ii) a Acid catalyst Yb (CF)₃SO₃)₃The dosage is 0-0.01 kg (kg substrate)^-1；

The reaction is divided into two temperature programs, wherein the two temperature programs are that the temperature is increased to 210-230 ℃ again at 120-135 ℃;

the time of the two temperature procedures is 3-5 hours and 3-8 hours respectively.

10. The method of claim 1, wherein:

the solvent used as the precursor of the diesel oil by photocatalysis is one or more than two of acetonitrile, acetone, 1, 4-dioxane and tetrahydrofuran; the hydrodeoxygenation solvent is one or more than two of cyclohexane, normal hexane, normal heptane and cyclopentane.