CN107814676B

CN107814676B - Preparation method of decahydronaphthalene and tetrahydronaphthalene

Info

Publication number: CN107814676B
Application number: CN201610822812.3A
Authority: CN
Inventors: 李宁; 陈芳; 张涛; 李广亿; 王爱琴; 王晓东; 丛昱
Original assignee: Dalian Institute of Chemical Physics of CAS
Current assignee: Dalian Institute of Chemical Physics of CAS
Priority date: 2016-09-14
Filing date: 2016-09-14
Publication date: 2021-12-28
Anticipated expiration: 2036-09-14
Also published as: CN107814676A

Abstract

The present invention relates to a new route for synthesizing decahydronaphthalene and tetrahydronaphthalene by using polycyclic ketone or polycyclic alcohol as raw material. The decahydronaphthalene and tetrahydronaphthalene obtained by the method can be directly used as substitutes of aviation kerosene and diesel oil or used as additives for improving the density and the heat stability of fuel. The invention is divided into four parts: 1) the polycyclic ketone is hydrogenated under the promotion action of a metal catalyst to obtain polycyclic alcohol; 2) dehydrating and isomerizing the polycyclic alcohol under the action of acid catalysis to obtain octahydronaphthalene; 3) hydrogenating octahydronaphthalene under the action of a metal catalyst to obtain decahydronaphthalene; 4) the octahydronaphthalene is dehydrogenated under the action of metal catalyst to prepare tetrahydronaphthalene.

Description

Preparation method of decahydronaphthalene and tetrahydronaphthalene

Technical Field

The invention relates to a new route for synthesizing decahydronaphthalene by taking polycyclic ketone or polycyclic alcohol as a raw material, which comprises the following four parts: 1) the polycyclic ketone is hydrogenated under the action of a metal catalyst to obtain polycyclic alcohol; 2) dehydrating and isomerizing the polycyclic alcohol under the action of an acid catalyst to obtain octahydronaphthalene; 3) hydrogenating octahydronaphthalene under the action of a metal catalyst to obtain decahydronaphthalene; 4) the octahydronaphthalene is dehydrogenated under the action of a metal catalyst to obtain the tetrahydronaphthalene.

Background

Aviation kerosene is a liquid fuel with great international demand at present and generally consists of mixed hydrocarbons with 8-16 carbon atoms. At present, aviation kerosene is mainly obtained by petroleum refining, however, due to the non-renewable nature of fossil resources and the growing concern of people on environmental problems, the search for renewable organic carbon sources to replace petroleum for preparing aviation kerosene is a research hotspot of all countries in the world. Compared with fossil energy, the biomass fuel has the characteristics of renewability and carbon dioxide neutrality. The sulfur dioxide emitted by the biological aviation kerosene during combustion is far lower than that of the mineral fuel oil. Therefore, the research and development of the biological aviation kerosene have important strategic significance for relieving the dependence degree of China on imported crude oil, ensuring the energy safety of China and obtaining the competitive advantage of green and low carbon.

The rise of biomass fuel has undergone a certain development process. The first generation of biomass fuel uses corn, soybean and the like as raw materials to prepare bioethanol and biodiesel through reactions such as fermentation, ester exchange and the like. The route takes edible grains as raw materials, and is not suitable for the national situation of more people and less land of China. The second generation biomass fuel takes agricultural and forestry wastes as raw materials and mainly generates fuel through three ways: 1) the biomass is gasified to generate synthesis gas, and then the alkane is prepared by Fischer-Tropsch synthesis. The process is mature, but needs high-temperature and high-pressure conditions, so that the energy consumption is huge; 2) the biomass is pyrolyzed at high temperature to generate biomass oil, and the biomass oil is deoxidized and upgraded to form liquid fuel. The process is complex, and the prepared biomass oil has poor quality, cannot be directly used as engine fuel and needs further refining; 3) the biomass is subjected to chemical and biological treatment (including hydrolysis, fermentation, selective hydrogenation and the like) to obtain a small molecular platform substance, and the small molecular platform substance is used as a raw material to obtain the aviation kerosene chain length (C) through a carbon-carbon coupling reaction₈-C₁₆) The oxygen-containing organic compound of (1). Finally, theAnd carrying out hydrodeoxygenation reaction on the oxygen-containing organic compounds to prepare liquid alkane. The process conditions are relatively mild, and the synthetic route is flexible and diverse.

The method for synthesizing the aviation kerosene by the route III comprises the following steps:

1. hydroxyalkylation/alkylation-hydrodeoxygenation

In 2011, Corma et al reported that acid catalyzed alkylation of methylfuran with butyraldehyde, 5-methylfurfural, 5-hydroxymethylfurfural and their own trimerization produced oxygenated organic compounds with a range of aviation kerosene or diesel chain lengths, after which they obtained a series of aviation kerosene branched hydrocarbons with lower freezing points by hydrodeoxygenation of these compounds (angew.chem.int.ed.2011,50, 1-5). However, the method adopts sulfuric acid and methyl benzene sulfonic acid as catalysts, which causes corrosion to equipment and pollution to the environment. Next, the subject group reported the alkylation of 5-methylfurfural with 2-methylfuran using Pt/C, Pt/C-TiO₂As the hydrodeoxygenation catalyst, higher liquid-phase alkane yield is obtained. On the basis, a series of solid acid catalysts catalyze methylfuran to react with furfural, butyraldehyde, acetone, hydroxyacetone and levulinate to synthesize a series of oxygen-containing organic compounds with the chain length range of aviation kerosene or diesel oil, and then a series of aviation kerosene branched-chain hydrocarbons with lower solidifying points are obtained by hydrodeoxygenation of the compounds. The method has relatively high cost by taking the selective hydrogenation product of furfural, namely methyl furan, as a raw material (Chinese patent application No. 201110346501.1; Chinese patent No. 201210169817.2).

2. Aldol condensation reaction-hydrodeoxygenation reaction

In 2005, Dumesic, Huber et al [ Science,2005,308,1446-]And patent [ US7,671,246]Reports that the preparation of C from hydroxymethylfurfural or furfural and acetone as raw materials through base-catalyzed aldol condensation reaction and hydrogenation and hydrodeoxygenation reactions₈To C₁₅A range of liquid alkanes. The authors used Pt/SiO₂-Al₂O₃The hydrodeoxygenation catalyst adopts a fixed bed four-phase flow reactor, and needs to be reacted in the processThe organic solvent (such as hexadecane) is introduced to prevent the catalyst from being deactivated, and the process is complicated. In 2008, this group of subjects used phosphorylated niobium oxides as a support instead of silicon aluminum composite oxides. It is found that the reaction system can obtain good effect without introducing organic solvent after adopting new carrier, thereby simplifying the process (ChemSusChem,2008,1, 417-. However, since the alkanes synthesized in this process are all straight-chain alkanes, the freezing points of these hydrocarbons are very high (n-pentadecane: 8.5-10 ℃, n-tridecane: -5.5 ℃, n-dodecane: -12 ℃), which does not meet the requirements of aviation kerosene (melting point lower than-40 ℃). Further hydroisomerization treatment is required to be used as aviation kerosene. On the basis, the group takes furfural as a substrate, and the furfural is respectively subjected to aldol condensation and hydrodeoxygenation with 3-pentanone and methyl isobutyl ketone under the solvent-free condition to obtain C₉-C₁₀The liquid alkane synthesized by the method is branched alkane, and the product can be used in aviation kerosene without isomerization.

3. Deoxygenation reaction-olefin polymerization reaction-hydrogenation reaction

In 2010, Dumesic et al [ Science,2010,327,1110-]It is reported that gamma-valerolactone is used as a raw material to prepare C through ring-opening decarboxylation reaction and olefin polymerization reaction₈To C₁₆A range of liquid olefins. The authors use SiO as₂/Al₂O₃Amberlyst-70 is a polymerization catalyst, and realizes the growth of carbon chains and the removal of oxygen atoms in a continuous fixed bed reactor. Then, the group explores a new path for synthesizing diesel oil by taking gamma-valerolactone as a raw material, namely the gamma-valerolactone is subjected to Pd/Nb reaction₂O₅Ring-opening hydrogenation is carried out to obtain valeric acid; then passes through Ce_0.5Zr_0.5O₂Ketonization reaction is carried out under catalysis to prepare 5-nonanone; the 5-nonanone is sequentially hydrogenated and dehydrated to obtain C₉A mixture of olefins; then obtaining C under the catalysis of Amberlyst-70₉-C₁₈The olefin can be used as diesel oil after being hydrogenated.

In summary, the aviation kerosene currently synthesized from biomass is mainly chain alkane. Compared with the traditional aviation kerosene (mixture of cyclic hydrocarbon and chain hydrocarbon), the high-density aviation kerosene has the defects of lower density and volume heat value and poor sealing property. In practical application, the fuel oil needs to be mixed with the traditional aviation kerosene to achieve the technical index of the current aviation kerosene. Decahydronaphthalene is added into various aviation fuel oils because of high volume heat value and thermal stability, and is even an important component of special aviation oil of certain types; the tetrahydronaphthalene has higher density and can be added into aviation kerosene to improve the density and the sealing performance of the aviation kerosene. Therefore, the development of the synthesis of decalin and tetralin with higher density and heat stability from the biomass platform compound has important application value, and is more beneficial to the industrialization of the biomass aviation kerosene technology. The cyclopentylidene cyclopentanone can be obtained from cyclopentanone which is a water-phase selective hydrogenation product of a biomass platform compound furfural through a self aldol condensation reaction with high yield; and the cyclopentylcyclopentanone, cyclopentylidene cyclopentanol, or cyclopentylcyclopentanol may be obtained by hydrogenation of cyclopentylidene cyclopentanone or by the Guerbet reaction of the biomass platform compound cyclopentanol.

Disclosure of Invention

The invention aims to provide a new route for preparing decahydronaphthalene and tetrahydronaphthalene from a lignocellulose-derived platform compound.

The invention is realized by the following technical scheme:

firstly, polycyclic ketone is hydrogenated under the action of a metal catalyst to obtain polycyclic alcohol; the raw materials are one or a mixture of two of the materials in the table 1;

TABLE 1 specific structural formulas of polycyclic ketones

The metal catalyst comprises Raney Ni, Raney Co, Raney Cu, nickel aluminum hydrotalcite, cobalt aluminum hydrotalcite and supported Pt, Pd, Ru, Rh, Ir, Ni, Co and Cu catalyst, wherein the carrier of the supported catalyst comprises one or the mixture of more than two of cerium oxide, aluminum oxide, magnesium oxide, active carbon, silicon oxide, molecular sieve and the like;

load type metalThe catalyst is prepared by a formaldehyde reduction method and an isovolumetric impregnation method respectively. The operation method of the formaldehyde reduction method comprises the following steps: ultrasonically dispersing a carrier by using water, dripping a metal precursor solution with the weight percentage of 2-40% at room temperature, and stirring for 1 h; standing overnight, adding NaOH solution at 45 deg.C to adjust pH to 9-10; adding excessive formaldehyde solution while stirring, and stirring for 1-2 h at 85 ℃; cooling and washing until no Cl is formed^-Drying in an oven at 80 ℃ for 4-10 h; the catalyst obtained by this process is labelled M-CR;

the operation method of the equal-volume impregnation is as follows: adding 2-40% of metal precursor solution into a corresponding carrier according to a metering ratio, soaking in equal volume, standing for 4-12 h, drying for 6-12 h, and finally reducing for 1-4 h in a hydrogen atmosphere at 100-600 ℃; the catalyst obtained from this process was labeled M-IP.

The reaction is directly carried out under the condition of liquid state without solvent; the reaction temperature is between 20 ℃ and 300 ℃, and preferably between 20 ℃ and 150 ℃; the reaction pressure is between 0.1MPa and 10.0MPa, and preferably between 1MPa and 4 MPa; when the kettle type reactor is selected, the reaction time is 0.5h-12h, and the amount of the catalyst is 0.1% -50% of the mass of the reaction raw materials, preferably 1% -10%; when a fixed bed reactor is selected, the mass space velocity of the reaction raw material/catalyst is 0.1h^-1-10.0h^-1，H₂The molar ratio to the substrate is from 8 to 1500, preferably from 8 to 100.

Secondly, carrying out dehydration and isomerization reaction on polycyclic alcohol under the catalysis of acid to obtain octahydronaphthalene;

the raw material is one or a mixture of more than two of the raw materials in the table 2, and can be purchased commercially directly or used after the hydrogenation product in the step one is purified;

TABLE 2 specific structural formula of polycyclic alcohols

The acid catalyst comprises liquid acid and solid acid, wherein the liquid acid comprises one or a mixture of more than two of sulfuric acid, hydrochloric acid, phosphoric acid and acetic acid; the solid acid comprises one or more of acidic molecular sieve, acidic metal oxide, phosphotungstic acid, phosphomolybdic acid, p-toluenesulfonic acid, sulfonated carbon and acidic resin; the molecular sieve is H-Y, HZSM-5, etc., the metal oxide is niobium oxide, tantalum oxide, etc., and the acidic resin is Amberlyst series catalyst, Nafion resin, etc.

The reaction temperature of the reaction is between 20 ℃ and 300 ℃, preferably between 50 ℃ and 140 ℃; the reaction pressure is 0.1MPa-10.0MPa, preferably 0.1MPa-1 MPa; the reaction can be carried out under the condition of no solvent; when a kettle type reactor is adopted, the reaction time is 4-12 h, and the amount of the acid catalyst is 0.1-50% of the mass of the reaction raw materials, preferably 5-20%; when a fixed bed reactor is adopted, the mass space velocity of the reaction raw material/catalyst is 0.1h^-1-10.0h^-1，N₂The molar ratio to the substrate is 8 to 1500. When a water separator device is adopted, the reaction time is 12-24 h, and the amount of the acid catalyst is 1-50% of the mass of the reaction raw materials, preferably 5-20%;

thirdly, the octahydronaphthalene which is a polycyclic alcohol dehydration-isomerization product is subjected to hydrogenation reaction through a metal catalyst to prepare decahydronaphthalene;

the preparation method of the supported catalyst is the same as the first step and comprises a formaldehyde reduction method and an isometric immersion method;

the reaction is directly carried out under the condition of liquid state without solvent; the reaction temperature is between 20 ℃ and 200 ℃, and preferably between 20 ℃ and 150 ℃; the reaction pressure is between 0.1MPa and 10.0MPa, preferably between 0.1MPa and 3.0 MPa; when the kettle type reactor is selected, the reaction time is 0.5h-12h, and the amount of the catalyst is 0.1% -50% of the mass of the reaction raw materials, preferably 1% -5%; when a fixed bed reactor is selected, the mass space velocity of the reaction raw material/catalyst is 0.1h^-1-10.0h^-1，H₂The molar ratio to the substrate is from 8 to 1500, preferably from 8 to 100.

Fourthly, dehydrogenating octahydronaphthalene which is a polycyclic alcohol dehydration-isomerization product through a metal catalyst to prepare tetrahydronaphthalene;

the type and preparation method of the metal catalyst are the same as those of the third step.

The reaction is directly carried out under the condition of liquid state without solvent; the reaction temperature is between 20 ℃ and 200 ℃, preferably between 50 ℃ and 170 ℃; the reaction pressure is between 0.1MPa and 10.0MPa, preferably between 0.1MPa and 3.0 MPa; when the kettle type reactor is selected, the reaction time is 0.5h-12h, and the amount of the catalyst is 0.1% -50% of the mass of the reaction raw materials, preferably 1% -5%; when a fixed bed reactor is selected, the mass space velocity of the reaction raw material/catalyst is 0.1h^-1-10.0h^-1，N₂The molar ratio to the substrate is from 8 to 1500, preferably from 8 to 100.

By adopting the technical scheme, the decahydronaphthalene or the tetrahydronaphthalene can be obtained with high yield, and a cheap and simple novel synthetic route for preparing the decahydronaphthalene and the tetrahydronaphthalene by taking the lignocellulose derivative as the raw material is realized.

The method synthesizes the decahydronaphthalene and the tetrahydronaphthalene by a biomass route for the first time, and compared with the existing coal decahydronaphthalene route, the method has the advantages of high conversion rate and good selectivity.

Drawings

FIG. 1 is a GC-MS spectrum of a polycyclic ketone hydrogenation reaction;

FIG. 2 is a GC-MS spectrum of a dehydration isomerization reaction of a polycyclic alcohol;

FIG. 3 is a GC-MS spectrum of the hydrogenation of octahydronaphthalene;

FIG. 4 is a GC-MS spectrum of dehydrogenation reaction of octahydronaphthalene;

FIG. 5 is a graph of polycyclic alcohol conversion versus time over different catalysts;

FIG. 6 is a graph of the yield of octahydronaphthalene versus time for different catalysts.

Detailed Description

Examples 1 to 20

1. Preparation of the catalyst:

1) preparation of metal catalyst:

raney Ni, Raney Co, Raney Cu are commercial catalyst products which are directly purchased; the nickel-aluminum hydrotalcite (NiAl-HT) is prepared by mixing Ni (NO) with a molar ratio of 3:1₃)₂·6H₂O and Al (NO)₃)₃·9H₂Dropping NaOH and NaCO into the O mixed solution at a rate of 3mL/min₃The dropping process was carried out in a water bath at 65 ℃ with vigorous stirring. After the dropwise addition, stirring and aging are continued for 18h, and then the mixture is filtered, washed, dried at 80 ℃ overnight and reduced at 500 ℃ for 2h before use.

The catalyst prepared by the formaldehyde liquid phase reduction method comprises the following steps: ultrasonically dispersing a carrier by using water, dripping a metal precursor solution with the weight percentage of 2-40% at room temperature, and stirring for 1 h; standing overnight, adding NaOH solution at 45 deg.C to adjust pH to 9-10; adding excessive formaldehyde solution while stirring, and stirring for 1-2 h at 85 ℃; cooling and washing until no Cl is formed^-Drying in an oven at 80 ℃ for 4-10 h; the catalyst obtained by this process is labelled M-CR;

the catalyst prepared by the isometric impregnation method comprises the following steps: adding a precursor solution with a certain concentration into a corresponding carrier according to a metering ratio, soaking in the same volume, standing for 4-12 h, drying in an oven at 120 ℃ for 6-12 h, and finally reducing for 1-4 h in a hydrogen atmosphere at 500 ℃ before use. The catalyst obtained from this process was labeled M-IP. The carriers used in the present invention include cerium oxide, aluminum oxide, magnesium oxide, silicon oxide, activated carbon, niobium oxide and molecular sieves (HZSM-5, H β) all commercially available; the metal precursor comprises palladium chloride, chloroplatinic acid, chloroiridic acid, rhodium chloride, ruthenium chloride, nickel nitrate, copper nitrate, cobalt nitrate and the like; the catalysts obtained are shown in Table 3.

TABLE 3 Supported Metal catalysts

Examples	Catalyst and process for preparing same
		Example 1	Ru/C-CR
Example 2	Pd/C-CR
		Example 3	Pt/C-CR
Example 4	Rh/C-CR
		Example 5	Ir/C-CR
Example 6	Ru/C-IP
		Example 7	Ni/C-IP
Example 8	Cu/C-IP
		Example 9	Co/C-IP
Example 10	Ni/MgO-IP
		Example 11	Ni/SiO₂-IP
Example 12	Ni/CeO₂-IP
		Example 13	Ni/Hβ-IP
Example 14	Ni/HZSM-5-IP
		Example 15	Ni/γ-Al₂O₃-IP
Example 16	Ni/Nb₂O₅-IP
		Example 17	NiAl-HT
Example 18	Raney Ni
		Example 19	Raney Co
Example 20	Raney Cu

2) Preparation of acid catalyst:

HY, HZSM-5, Amberlyst series catalyst, Nafion resin and the like are all commercial products; ZrP is ZrCl₂O·8H₂O (1.0M,31.9mL) and NH₄H₂PO₄(1.0M,63.8mL), filtering, washing, drying at 100 ℃, and roasting at 400 ℃ for 3 h. The sulfonated carbon catalyst is obtained by sulfonating commercially available coconut shell carbon under the action of concentrated sulfuric acid.

All catalysts were dried in an oven at 120 ℃ for 12h before use.

2. Polycyclic ketone hydrogenation

Examples 21 to 66

1) A kettle reactor is adopted, 10g of polycyclic ketone a1 and 0.5g of catalyst are added into a 100mL reaction kettle, and H is carried out at 120 DEG C₂Under the pressure of 3MPaStirring for 3 h. The detailed reaction results are shown in Table 4.

TABLE 4 polycyclic ketone hydrogenation and results

As can be seen from Table 4, the acid-base nature of the catalyst has a large effect on the selectivity of the product, and both strong acid and strong base supports are detrimental to the formation of the polycyclic alcohol product. Among many catalysts, the activity and selectivity of the Ru/C catalyst to the target product are optimal, and the preparation method has no influence on the reaction. Considering that the Ru/C-CR catalyst is commercially available, we chose the catalyst for further study. The effect of reaction temperature, reaction pressure, reaction time and catalyst amount on the reaction was examined and the results are shown in Table 5.

TABLE 5 Effect of temperature, pressure, time and amount of catalyst on the hydrogenation of polycyclic ketones

As can be seen from Table 5, when the temperature is higher than 120 ℃, the pressure is higher than 3MPa, the reaction time is 3h, and the catalyst dosage/raw material mass is more than 5%, the optimal yield of the target product can be obtained, and the yield is as high as 99%.

2) A fixed bed reactor is adopted: the polycyclic ketone a1 is pumped into a fixed bed reactor at a certain speed by a high performance liquid chromatography pump, Ru/C-CR is used as a catalyst, and the influence of temperature, pressure and space velocity on the reaction is examined. The results are shown in Table 6.

TABLE 6 influence of temperature, pressure, Mass space velocity on the hydrogenation of polycyclic ketones

As can be seen from Table 6, a fixed bed reactor was used under the reaction conditions of T120 ℃ and a mass space velocity of 1 hour^-1Hydrogen flow at a pressure of 3MPaThe amount is 200mL min^-1The yield of the desired target product was at most 97%.

3. Polycyclic alcohol dehydration and isomerization reaction: after purifying the hydrogenation product in the last step, one or more than two mixtures of polycyclic alcohols obtained or other alcohol compounds in the table 2 are used as raw materials in the reaction.

Examples 67 to 101

1) A fixed bed reactor is adopted: 1.0g of catalyst was charged into a reaction tube, the pressure in the reactor was maintained at 0.1MPa, the temperature was 120 ℃ and the nitrogen flow rate was 150mL/min, and the raw material b was introduced₁The resulting mixture was pumped into the reactor by a high performance liquid chromatography pump at 0.04 mL/min. The reaction results are shown in Table 7.

TABLE 7 dehydroisomerization of polycyclic alcohols and results thereof

As can be seen from Table 7, the different metal catalysts are active in the dehydration of polycyclic alcohols. The Amberlyst-15 has the best selectivity to octahydronaphthalene. Therefore, we examined the effect of different hydrogen pressures, reaction temperatures, mass space velocities of the reaction raw materials and the catalyst, and nitrogen flow rates on the dehydration reaction in a fixed bed reactor with Amberlyst-15 as the catalyst, and the results are shown in Table 8.

TABLE 8 influence of temperature, pressure, Mass space velocity on the dehydration isomerization of polycyclic alcohols

2) A kettle type reactor is adopted, wherein 45g of raw materials and 4.5g of acid catalyst are added into a 100mL reaction kettle and stirred for 6h at 120 ℃ and normal pressure. The detailed reaction results are shown in Table 9.

TABLE 9 influence of temperature, pressure, time and catalyst amount on the hydroisomerization of polycyclic alcohols

As can be seen from table 9, for the liquid acid, included: hydrochloric acid, sulfuric acid, phosphoric acid, and acetic acid, because they contain water, make the octahydronaphthalene product poorly selective. Meanwhile, the tank reactor is inferior to the fixed bed reactor in selectivity to octahydronaphthalene by using the same catalyst.

3) Adopting a water separator reaction device: 38g of the starting material and 7.6g of the catalyst were charged into a 100mL round-bottomed flask, and they were stirred at 120 ℃ under normal pressure, and sampled at regular intervals, and the results of the conversion of the starting material and the yield of the product octahydronaphthalene are shown in FIGS. 5 and 6.

As can be seen from the figure, under the action of the three resin catalysts, polycyclic alcohol can be completely converted after reacting for 8 hours; the reaction time is prolonged, the yield of the octahydronaphthalene is gradually improved under the action of a Nafion catalyst, and the yield can reach 91% in 24 hours.

4. Hydrogenation reaction of octahydronaphthalene:

example 102-

1) Adopts a kettle type reactor, 10g of raw materials and 0.5g of catalyst are added into a 100mL reaction kettle, and H is carried out at 120 DEG C₂Stirring for 3 hours under the pressure of 3 MPa. The detailed reaction results are shown in Table 10.

TABLE 10 hydrogenation of octahydronaphthalene and product yield results

As can be seen from Table 10, it is easier to prepare decalin by hydrogenating octahydronaphthalene, and different catalysts have certain activity to the reaction. The yield of the noble metal supported catalyst decalin reaches 100%, but Ni-based catalysts in non-noble metal catalysts have excellent catalytic activity, and the acidic carrier is more beneficial to the generation of the decalin.

2) A fixed bed reactor is adopted: octahydronaphthalene is pumped into a fixed bed reactor at a certain speed by a high performance liquid chromatography pump, Pd/C-CR is used as a catalyst, and the influence of temperature, pressure and space velocity on the reaction is inspected. The results are shown in Table 11.

TABLE 11 influence of temperature, pressure and space velocity on the hydrogenation of octahydronaphthalene

As can be seen from Table 11, at 120 ℃ the space velocity was 3h^-1At the pressure of 0.5MPa, the decahydronaphthalene can be obtained with high yield by taking Pd/C-CR as a catalyst.

5. Dehydrogenation reaction of octahydronaphthalene:

example 135-161

1) A kettle reactor was used, in which 10g of the starting material and 0.5g of the catalyst were charged into a 100mL reaction kettle and stirred at 170 ℃ for 3 hours. The detailed reaction results are shown in Table 12.

TABLE 12 dehydrogenation of octahydronaphthalene and product yield results

As can be seen from Table 12, different catalysts have certain activity for the reaction, but the yield of tetrahydronaphthalene is very low because the generated hydrogen is hydrogenated in situ in the tank reactor, so that part of octahydronaphthalene is hydrogenated to obtain decahydronaphthalene.

2) A fixed bed reactor is adopted: octahydronaphthalene is pumped into a fixed bed reactor at a certain speed by a high performance liquid chromatography pump, Pd/C-CR is used as a catalyst, and the influence of temperature, pressure and space velocity on the reaction is examined under the nitrogen atmosphere. The results are shown in Table 13.

TABLE 13 influence of temperature, pressure and space velocity on the dehydrogenation of octahydronaphthalene

As can be seen from Table 13, at 170 ℃ the space velocity is 1h^-1The tetrahydronaphthalene can be obtained with high yield (85%) by taking Pd/C-CR as a catalyst under the pressure of 0.1 MPa.

Claims

1. A preparation method of decahydronaphthalene and tetrahydronaphthalene is characterized in that:

preparation of decalin:

1) under the action of a metal catalyst, polycyclic ketone is hydrogenated to obtain polycyclic alcohol;

2) under the action of an acid catalyst, polycyclic alcohol is dehydrated and isomerized to obtain octahydronaphthalene;

3) under the action of a metal catalyst, octahydronaphthalene is hydrogenated to obtain decahydronaphthalene;

and/or, preparation of tetrahydronaphthalene:

1') under the action of a metal catalyst, polycyclic ketone is hydrogenated to obtain polycyclic alcohol;

2') under the action of an acid catalyst, dehydrating and isomerizing polycyclic alcohol to obtain octahydronaphthalene;

3') under the action of a metal catalyst, dehydrogenating octahydronaphthalene to obtain tetrahydronaphthalene;

the atmosphere used in steps 1), 1'), 3) is hydrogen; the atmosphere used in steps 2), 2 '), 3') is nitrogen;

the polycyclic ketone is one or a mixture of more than two of a1, a2 and a 3:

a₁、

a₂、

a₃

in the steps 2) and 2'), the acid catalyst is a solid acid and comprises one or a mixture of more than two of sulfonated carbon, Amberlyst-45, Amberlyst-70, Amberlyst-36, Amberlyst-15, Nafio resin, HZSM-5 or HBeta;

the reactor adopts a fixed bed reactor;

the conditions of the fixed bed reactor were: the reaction pressure is between 0.1MPa and 10.0MPa, and the mass space velocity of the reaction raw material/catalyst is 0.1h^-1-10.0 h^-1；N₂Or H₂The molar ratio of the raw materials to the reaction raw materials is 8-1500;

the polycyclic ketone is one or a mixture of more than two of a1, a2 and a 3:

a₁、

a₂、

a₃

the polycyclic alcohol is one or a mixture of more than two of the following b1, b2 and b 3:

b₁、

b₂、

b₃。

2. the method of claim 1, wherein:

in step 1), step 1 '), step 3), and step 3'), the metal catalyst includes Raney Ni, Raney Co, Raney Cu, nickel aluminum hydrotalcite, cobalt aluminum hydrotalcite, and one or more of supported Pt, Pd, Ru, Rh, Ir, Ni, Co, Cu catalysts, wherein for the supported catalyst, the support includes one or more of cerium oxide, aluminum oxide, magnesium oxide, activated carbon, silicon oxide, and a molecular sieve.

3. The method of claim 1, wherein:

the reactions of step 1), step 2), step 3), step 1 '), step 2 ') and step 3 ') can all be carried out in the absence of a solvent at a temperature of from 20 ℃ to 300 ℃.