Catalyst for preparing 1,5-pentanediol via hydrogenolysis of tetrahydrofurfuryl alcohol, method and application thereof

Abstract

The present invention provides a method for preparing 1,5-pentanediol via hydrogenolysis of tetrahydrofurfuryl alcohol. The catalyst used in the method is prepared by supporting a noble metal and a promoter on an organic polymer supporter or an inorganic hybrid material supporter, wherein the supporter is functionalized by a nitrogen-containing ligand. When the catalyst is used in the hydrogenolysis of tetrahydrofurfuryl alcohol to prepare 1,5-pentanediol, a good reaction activity and a high selectivity can be achieved. The promoter and the nitrogen-containing ligand in the supporter are bound to the catalyst through coordination, thereby the loss of the promoter is significantly decreased, and the catalyst has a particularly high stability. The lifetime investigation of the catalyst, which has been reused many times or used continuously for a long term, suggests that the catalyst has no obvious change in performance, thus reducing the overall process production cost.

Claims

1. A catalyst used for preparing 1,5-pentanediol by hydrogenolysis of tetrahydrofurfuryl alcohol, characterized in that: said catalyst comprises a supporter, an active component supported on the supporter, and a promoter supported on the supporter; wherein, the supporter is a polystyrene grafted with a nitrogen-containing ligand; said active component is any one or more of the metal elements Rh, Ir, Pt, Pd, Ru and Au; said promoter is any one or more of the metal elements Re, Mo, W, V, Nb, Ta, Mn, and Sn; wherein the nitrogen-containing ligand in said polystyrene grafted with a nitrogen-containing ligand is any one of imidazole, pyridine, bipyridine and 1,10-phenanthroline.

2. The catalyst according to claim 1, characterized in that: said polystyrene grafted with a nitrogen-containing ligand has the following structural formula: ##STR00005## wherein, m=500-2,000, n=200-1,000.

3. The catalyst according to claim 2, wherein m=800-1500 and n=300-800.

4. The catalyst according to claim 2, characterized in that: based on the total weight of the catalyst, said active component is supported in an amount of 0.05-10 wt %; the molar ratio of the active component, the promoter and the nitrogen-containing ligand is 1:(0.01-2):(0.05-4).

5. The catalyst according to claim 4, characterized in that: based on the total weight of the catalyst, said active component is supported in an amount of 1-5 wt %.

6. The catalyst according to claim 4, characterized in that: the molar ratio of the active component, the promoter and the nitrogen-containing ligand is 1:(0.05-1):(0.1-2).

7. The catalyst according to claim 1, characterized in that: based on the total weight of the catalyst, said active component is supported in an amount of 0.05-10 wt %; the molar ratio of the active component, the promoter and the nitrogen-containing ligand is 1:(0.01-2):(0.05-4).

8. The catalyst according to claim 7, characterized in that: based on the total weight of the catalyst, said active component is supported in an amount of 1-5 wt %.

9. The catalyst according to claim 7, characterized in that: the molar ratio of the active component, the promoter and the nitrogen-containing ligand is 1:(0.05-1):(0.1-2).

10. A method for preparing the catalyst according to claim 1, characterized in that: the supporter is added into a soluble salt solution of the active component for isometric impregnation, and then dried at 80-120° C. for 6-24 hours; a soluble salt solution of the promoter is further used for isometric impregnation, and the impregnated supporter is then dried at 80-120° C. for 6-24 hours to obtain the catalyst.

11. The preparation method of the catalyst according to claim 10, characterized in that: the soluble salt of the active component is one or more compounds selected from the group consisting of rhodium chloride, chloroiridic acid, chloroplatinic acid, palladium chloride, ruthenium chloride and chloroauric acid; and the soluble salt of the promoter is one or more compounds selected from the group consisting of ammonium rhenate, ammonium molybdate, ammonium metatungstate, ammonium vanadate, niobiumtartrate, tantalumtartrate, manganese acetate and stannic chloride.

12. A method for preparing 1,5-pentanediol by hydrogenolysis of tetrahydrofurfuryl alcohol using the catalyst according to claim 1, characterized in that: the reaction is carried out in a batch reactor; the mass concentration of the aqueous solution of tetrahydrofurfuryl alcohol is 5-100%; the amount of the catalyst used is 1-10 wt % of the mass of tetrahydrofurfuryl alcohol; the reaction temperature is 50-150° C.; the hydrogen pressure is 1-20 MPa; the reaction time is 2-24 hours; or, the reaction is carried out in a fixed bed reactor; the mass concentration of the aqueous solution of tetrahydrofurfuryl alcohol is 5-100%; the reaction temperature is 50-150° C.; the hydrogen pressure is 1-20 MPa; the mass space velocity of tetrahydrofurfuryl alcohol feed liquid/catalyst in the fix bed reactor is 0.5-4 h.sup.−1; the volume space velocity of hydrogen/catalyst is 500-1500 h.sup.−1.

13. The method according to claim 12, characterized in that: the catalyst, before use, needs to be reduced in situ in the presence of hydrogen, and the reduction condition is as follows: the hydrogen pressure is 0.1-1 MPa; for each 100 g of the catalyst, the H.sub.2 flow rate is 0.2-10 L/min; the reduction temperature is 50-200° C.; and the reduction time is 1-10 hours.

14. The method according to claim 12, characterized in that: the reaction is carried out in a batch reactor; the reaction temperature is 60-120° C.; the hydrogen pressure is 2-10 MPa; the reaction time is 2-6 hours; or, the reaction is carried out in a fixed bed reactor; the reaction temperature is 60-120° C.; the hydrogen pressure is 2-10 MPa; the mass space velocity of tetrahydrofurfuryl alcohol feed liquid/catalyst in the fix bed reactor is 1-3 h.sup.−1; the volume space velocity of hydrogen/catalyst is 800-1200 h.sup.−1.

15. The method according to claim 13, characterized in that: the catalyst, before use, needs to be reduced in situ in the presence of hydrogen, and the reduction condition is as follows: the hydrogen pressure is 0.2-0.4 MPa; for each 100 g of the catalyst, the H.sub.2 flow rate is 1-5 L/min; the reduction temperature is 100-180° C.; and the reduction time is 2-6 hours.

Description

DETAILED DESCRIPTION

(1) The present invention will be further illustrated below with reference to examples, it should be noted that the examples are not the limitations for the scope of the present invention.

(2) The raw material tetrahydrofurfuryl alcohol was purchased from Zibo Hua'ao Chemical Co., Ltd.; the soluble salts of the active component—hereinafter also referred to as the soluble salts of the noble metal M (rhodium chloride, chloroiridic acid, chloroplatinic acid, palladium chloride, ruthenium chloride, chloroauric acid), and the soluble salts of the promoter P (ammonium rhenate, ammonium molybdate, ammonium metatungstate, ammonium vanadate, ruthenium chloride, niobiumtartrate, tantalumtartrate, manganese acetate, stannic chloride) were purchased from Sinopharm Group Chemical Reagents Co., Ltd. The supporters S, i.e., a polystyrene and a silica gel that were grafted with a nitrogen-containing ligand (imidazole, pyridine, bipyridine, 1,10-phenanthroline), were purchased from Sigma-Aldrich Reagent Company (the product numbers were 549363 (m=1240, n=320), 192074 (m=960, n=400), 589993 (m=1070, n=530), 561878 (m=1150, n=670); 56760 (x=7300, y=390), 537985 (x=6500, y=460), 537950 (x=8000, y=710), 569798 (x=7100, y=650), respectively). Their structural formulas are shown, respectively, as follows:

(3) ##STR00003## ##STR00004##

(4) In the following examples, “%” used is “molar percentage” unless specifically stated otherwise.

(5) The testing instruments used in the following examples are: a Shimadzu GC-2010 gas chromatograph (hydrogen flame detector, nitrogen used as carrier gas) is used for gas phase analysis, using a DB-5 capillary chromatography column (5% Phenyl Methyl Siloxan, 30 m×0.32 mm×0.25 μm), and a hydrogen flame detector (FID). The temperatures of the injector and the detector are both 280° C.; the column temperature is controlled by temperature programme: the initial column temperature of 100° C. is maintained for 0.5 minutes, and then the temperature is raised to 260° C. at a rate of 15° C./min, and it is maintained at 260° C. for 5 minutes. The column pressure is 8.5868 psi, and the flow rate is 1.5 mL/min. Injection volume: 0.2 μL. Conversion rate and selectivity are calculated using the area normalization method.

Examples 1˜24: Catalyst Preparation

(6) The preparation was carried out using isometric impregnation step by step. Firstly, soluble salts (rhodium chloride, chloroiridic acid, chloroplatinic acid, palladium chloride, ruthenium chloride, chloroauric acid) of noble metal M (Rh, Ir, Pt, Pd, Ru, Au) were separately prepared as aqueous solutions. Supporters S in powder were added into the above prepared aqueous solutions according to the ratios in Table 1, and the mixtures were stirred until homogeneously mixed. The supporters S were impregnated for 12 hours at room temperature, and then dried at 120° C. for 12 hours. Then, soluble salts (ammonium rhenate, ammonium molybdate, ammonium metatungstate, ammonium vanadate, niobiumtartrate, tantalumtartrate, manganese acetate, stannic chloride) of the promoter P (Re, Mo, W, V, Nb, Ta, Mn, Sn) were separately prepared as aqueous solutions; and they were added into the above impregnated supporters S which had been impregnated with noble metal M component, according to the ratios in Table 1; the mixture were stirred until homogenously mixed. After impregnated for 12 hours at room temperature, the impregnated supporters S were dried at 120° C. for 12 hours, obtaining catalysts with different content of active component.

(7) TABLE-US-00001 TABLE 1 Catalyst preparation Catalyst Noble Content of M:P:nitrogen-containing No. metal M Promoter P Supporter S M (wt %) ligand (molar ratio)  1# Rh Re polystyrene grafted with imidazole 5 1:0.5:0.5  2# Rh Mo silica gel grafted with pyridine 4 1:0.13:0.26  3# Rh W polystyrene grafted with pyridine 3 1:1:1.1  4# Rh V silica gel grafted with 2 1:0.05:0.25 1,10-phenanthroline  5# Rh Nb polystyrene grafted with pyridine 1 1:0.1:0.15  6# Rh Ta silica gel grafted with bipyridine 4.5 1:0.15:0.09  7# Rh Mn polystyrene grafted with 3.5 1:0.2:0.14 1,10-phenanthroline  8# Rh Sn silica gel grafted with imidazole 2.5 1:0.3:0.24  9# Rh Re silica gel grafted with pyridine 6.5 1:0.74:1.23 10# Ir Re polystyrene grafted with pyridine 4 1:0.4:0.36 11# Ir Mo silica gel grafted with bipyridine 3 1:0.6:0.72 12# Ir W Polystyrene 4.3 1:0.7:0.91 grafted with 1,10-phenanthroline 13# Ir V silica gel grafted with imidazole 2.6 1:0.8:1.12 14# Ir Nb polystyrene grafted with imidazole 3 1:0.9:1.44 15# Ir Ta silica gel grafted with pyridine 1.8 1:0.22:0.37 16# Ir Mn polystyrene grafted with bipyridine 1.2 1:0.34:0.61 17# Ir Sn silica gel grafted with 4.8 1:0.46:0.87 1,10-phenanthroline 18# Ir Mo polystyrene grafted with imidazole 8.9 1:0.86:1.39 19# Pt Re silica gel grafted with imidazole 4.1 1:0.58:0.29 20# Pt Mo polystyrene grafted with 2.5 1:0.63:0.63 1,10-phenanthroline 21# Pd W silica gel grafted with bipyridine 3.7 1:0.75:1.5 22# Pd V polystyrene grafted with pyridine 4.4 1:0.87:0.87 23# Ru Nb polystyrene grafted with imidazole 2.3 1:0.99:1 24# Ru Ta silica gel grafted with 1.7 1:0.81:0.9 1,10-phenanthroline 25# Au Mn polystyrene grafted with bipyridine 2.8 1:0.73:0.7 26# Au Sn silica gel grafted with pyridine 3.9 1:0.55:1 27# Au W silica gel grafted with bipyridine 9.5 1:0.91:1.98

Examples 28˜54: Catalyst Evaluation—Batch Reactor

(8) The catalyst evaluation of the present invention was carried out in a batch reactor, having a reactor volume of 5000 mL and made of stainless steel. A certain amount of catalyst was added into the reactor, and the catalyst was reduced in situ for 4 hours, at a reduction temperature of 150° C., a H.sub.2 pressure of 0.3 MPa and a H.sub.2 flow rate of 1.5 L/min. After the reduction, the temperature was lowered to the reaction temperature, and 3000 g of tetrahydrofurfuryl alcohol aqueous solution with a certain concentration was added; the temperature was adjusted to the reaction temperature, and hydrogen with a certain pressure was charged into the reactor to perform the reaction. The reaction was completed after a certain period of time. The specific reaction conditions were shown in Table 2. After the temperature was lowered and the pressure was released, a liquid sample was taken. The liquid sample was analyzed using the gas chromatograph equipped with a DB-5 capillary column and a flame ionization detector (FID) as described above.

(9) The catalyst of the present invention was reused in the batch reactor. After the previous reaction in the reactor was completed, the reaction liquid was removed through a filter built in the reactor and the catalyst was left in it. 3000 g of aqueous solution of tetrahydrofurfuryl alcohol with a certain concentration was added again into the reactor, and the temperature was adjusted to the reaction temperature; hydrogen with a certain pressure was charged into the reactor to perform the reaction. The reaction was completed after a certain period of time. The specific conditions were the same as those in the previous reaction.

(10) TABLE-US-00002 TABLE 2 Reaction conditions and results in the batch reactor Reaction conditions The The amount concentration of The first use The 10th reuse of tetrahydrofurfuryl Hydrogen Conversion Conversion catalyst alcohol Temperature pressure Time rate Selectivity rate Selectivity Examples Catalyst (wt %) (wt %) (° C.) (MPa) (h) (%) (%) (%) (%) 28 1# 6 50 100 5.5 2.5 95.2 95.0 94.5 95.3 29 2# 7 60 95 6 3 93.7 94.3 93.0 94.7 30 3# 5 40 100 4.5 4 94.5 91.8 94.7 91.8 31 4# 4 20 105 8 3.5 95.3 96.0 95.2 96.1 32 5# 3 70 120 7 4 92.4 95.3 92.5 95.2 33 6# 4.5 50 90 9 5.6 93.3 96.9 93.3 96.9 34 7# 5.5 30 110 10 4.8 94.2 97.5 94.2 97.5 35 8# 6.5 10 85 7.5 6 95.7 93.4 95.1 94.4 36 9# 7.5 80 115 8.5 4.2 92.1 97.2 92.5 96.9 37 10# 8.5 90 80 5 5.4 97.3 98.0 97.2 98.0 38 11# 10 5 90 4 4.7 96.9 93.1 97.0 93.2 39 12# 8 15 70 5.5 5.8 97.3 90.9 96.8 91.5 40 13# 5 25 75 6 5.1 96.4 91.6 96.3 91.7 41 14# 6.5 10 80 4.5 4.3 95.2 91.3 95.4 91.2 42 15# 4 20 90 8 3.5 98.3 92.7 98.0 93.2 43 16# 2.5 25 100 7 4.7 92.1 95.4 93.1 94.9 44 17# 5 30 95 9 2.9 98.2 94.0 98.1 94.2 45 18# 6.5 25 100 10 3.4 96.5 97.3 96.7 97.2 46 19# 4.5 20 105 7.5 4.3 93.7 94.1 93.8 94.0 47 20# 3.5 15 120 8.5 5.4 94.1 93.7 94.5 93.2 48 21# 7.5 10 90 5 5.1 93.5 94.8 93.2 95.0 49 22# 10 5 110 4 4.7 94.7 95.0 95.7 94.2 50 23# 6 10 85 6 3.9 96.8 97.1 96.8 97.3 51 24# 4 20 115 8 2.1 97.6 94.9 97.9 94.6 52 25# 2 75 105 7 5.7 95.7 97.2 95.8 97.0 53 26# 5 45 90 5.5 3.3 91.3 98.4 91.5 98.3 54 27# 1 100 100 8 2 99.2 96.3 99.0 96.5

(11) As can be seen from Table 2, different hydrogenolysis catalysts all show good activity and 1,5-pentanediol selectivity in the hydrogenolysis reaction of tetrahydrofurfuryl alcohol, and a high conversion rate can be obtained in a relatively short period of time. In particular, the supporter grafted with a nitrogen-containing ligand provides excellent catalyst stability, and the catalyst activity is substantially maintained after 10 times of reuse.

Examples 55˜81: Catalyst Evaluation—Fixed Bed Reactor

(12) The catalyst evaluation of the present invention was carried out in a fixed bed reactor, which was a stainless steel pipe having an external diameter of 40 mm, an internal diameter of 20 mm and a length of 1000 mm. 50 g of the catalyst was loaded into the reactor. Before the reaction, the loaded catalyst was reduced in situ for 4 hours, at a reduction temperature of 150° C., a H.sub.2 pressure of 0.3 MPa and a H.sub.2 flow rate of 1.5 L/min. After the reduction, the temperature was lowered to the reaction temperature, the hydrogen/catalyst volume space velocity was set at 1000 h.sup.−1, the flow rate of tetrahydrofurfuryl alcohol aqueous solution was adjusted to the desired mass space velocity of tetrahydrofurfuryl alcohol feed liquid/catalyst, and the pressure was adjusted to the desired reaction pressure. The specific reaction conditions were shown in Table 2. A liquid sample was taken online, and was analyzed using the gas chromatography equipped with a DB-5 capillary column and a flame ionization detector (FID) as described above.

(13) TABLE-US-00003 TABLE 3 Reaction conditions and results in the fixed bed reactor Reaction conditions Mass space Results of Results of The veolcity of running 4 hours running 200 hours concentration of Hydrogen tetrahydrofurfuryl Conversion Conversion tetrahydrofurfuryl Temperature pressure alcohol/catalyst rate Selectivity rate Selectivity Examples Catalyst alcohol (wt %) (° C.) (MPa) (h.sup.−1) (%) (%) (%) (%) 55 1# 50 100 5.5 2.5 92.3 95.0 92.1 95.2 56 2# 60 95 6 3 98.8 94.3 98.9 94.3 57 3# 40 100 4.5 2 94.5 98.1 94.6 98.0 58 4# 20 105 8 1.5 97.8 96.0 97.5 96.4 59 5# 70 120 7 1 94.0 95.3 94.2 95.5 60 6# 50 90 9 1.6 93.3 96.9 93.5 96.8 61 7# 30 110 10 1.8 94.2 97.5 94.1 97.6 62 8# 10 85 7.5 2 95.7 93.4 95.4 93.5 63 9# 80 115 8.5 2.2 99.2 97.2 99.0 97.4 64 10# 90 80 5 2.4 98.7 98.0 98.5 98.3 65 11# 5 90 4 2.6 96.9 93.1 97.0 93.0 66 12# 15 70 5.5 2.8 97.3 92.9 97.2 92.8 67 13# 25 75 6 1.1 96.4 91.6 96.5 91.8 68 14# 10 80 4.5 1.3 95.2 91.3 95.6 91.1 69 15# 20 90 8 1.5 98.3 97.7 98.2 97.6 70 16# 25 100 7 1.7 92.1 95.4 92.5 95.7 71 17# 30 95 9 1.9 98.2 96.9 98.4 96.8 72 18# 25 100 10 1.4 96.5 97.3 96.3 97.4 73 19# 20 105 7.5 1.3 93.7 94.1 93.4 94.3 74 20# 15 120 8.5 1.1 94.1 93.7 94.0 93.9 75 21# 10 90 5 1 93.5 94.8 93.2 94.5 76 22# 5 110 4 1.7 90.7 96.0 90.8 96.2 77 23# 10 85 6 1.9 96.8 97.1 96.4 97.3 78 24# 20 115 8 2.1 97.6 98.5 97.7 98.4 79 25# 75 105 7 1.7 97.5 96.8 97.3 96.7 80 26# 45 90 5.5 1.3 93.3 97.4 93.5 97.5 81 27# 100 100 8 2 98.5 95.2 98.7 95.3

(14) As can be seen from Table 3, in the fixed bed reactor, different hydrogenolysis catalysts also show good activity and 1,5-pentanediol selectivity for the hydrogenolysis reaction of tetrahydrofurfuryl alcohol. And as shown in these 200 hours lifetime tests, the supporter grafted with a nitrogen-containing ligand provides excellent catalyst stability.

Comparative Examples 1˜10: Preparation of Polystyrene Supported Catalyst and Silica Gel Supported Catalyst

(15) In order to better embody the advantages of the catalysts in the present application, 10 representative catalysts were prepared by directly using polystyrene and silica gel as supporters, which were not grafted with a nitrogen-containing ligand. That is, the metal and the promoter contents, the preparation method and examples were the same as described for the catalysts of 1#, 2#, 10#, 11#, 13#, 19#, 21#, 23#, 26# and 27#, respectively.

(16) TABLE-US-00004 TABLE 4 Preparation of comparative catalyst Content Comparative Noble Promoter of M M:P catalyst No. metal M P Supporter (wt %) (molar ratio) 1-1#  Rh Re polystyrene 5 1:0.5 1-2#  Rh Mo silica gel 4 1:0.13 1-10# Ir Re polystyrene 4 1:0.4 1-11# Ir Mo silica gel 3 1:0.6 1-13# Ir V silica gel 2.6 1:0.8 1-19# Pt Re silica gel 4.1 1:0.58 1-21# Pd W silica gel 3.7 1:0.75 1-23# Ru Nb polystyrene 2.3 1:0.99 1-26# Au Sn silica gel 3.9 1:0.55 1-27# Au W silica gel 9.5 1:0.91

Comparative Examples 11˜20: Performance Evaluation of Polystyrene Supported Catalyst and Silica Gel Supported Catalyst

(17) In order to better embody the advantages of catalysts in the present application, catalysts 1-1#˜1-10# in the comparative examples were evaluated using the batch reactor, and the evaluation conditions thereof were the same as described for the catalysts 1#, 2#, 10#, 11#, 13#, 19#, 21#, 23#, 26# and 27# in examples 28˜54.

(18) TABLE-US-00005 TABLE 5 Reaction conditions and results in the batch reactor Reaction conditions The first use The 10th reuse The amount The concentration of Tem- Conversion Conversion Comparative of catalyst tetrahydrofurfuryl perature Pressure Time rate Selectivity rate Selectivity examples Catalyst (wt %) alcohol (wt %) (° C.) (MPa) (h) (%) (%) (%) (%) 11 1-1# 6 50 100 5.5 2.5 70 95.0 25 86.4 12 1-2# 7 60 95 6 3 78 94.3 28 85.7 13 1-10# 8.5 90 80 5 5.4 82 97.2 32 87.6 14 1-11# 10 5 90 4 4.7 77 98 37 87.1 15 1-13# 5 25 75 6 5.1 73 90.9 23 82.3 16 1-19# 4.5 20 105 7.5 4.3 67 74.1 17 72.8 17 1-21# 7.5 10 90 5 5.1 65 69.8 16 63.4 18 1-23# 6 10 85 6 3.9 66.8 71 19.8 75 19 1-26# 5 45 90 5.5 3.3 72.1 85.4 22.1 79.2 20 1-27# 1 100 100 8 2 76 85 26 72.5

(19) As can be seen from Table 5, catalysts, supported directly by polystyrene and silica gel which were not grafted with a nitrogen-containing ligand, were significantly inferior in activity and selectivity to the catalysts prepared in the present application. And their activity decreased rapidly in reuse and their stability was poor.

(20) The above is only preferred embodiments of the present invention, and the scopes of the present invention are not limited thereto; any person skilled in the art would recognize many other variations or alternatives within the technical scopes disclosed in the present invention. Such variations and alternatives are included within the scopes of the invention to be claimed.