A rare earth metal modified transition metal catalyst and a method for catalytically synthesizing pentanediamine

Abstract

The application provides a rare earth metal modified transition metal catalyst and a method for synthesizing pentanediamine by catalysis, and belongs to the technical field of chemical synthesis, and aims to solve the technical problem of low selectivity of chemical decarboxylation synthesis of pentanediamine. The rare earth metal modified transition metal catalyst is modified by using a rare earth metal on a transition metal catalyst; the transition metal catalyst is a transition metal supported molecular sieve, and the transition metal is limited in the molecular sieve to serve as a reaction active center; after the modification of the rare earth metal, the molecular sieve carrier or skeleton is not affected, the transition metal reaction active center is unchanged, but the catalytic decarboxylation reaction performance is significantly improved. A mixed solution is obtained by mixing lysine or a lysine salt, water and the rare earth metal modified transition metal catalyst, and pentanediamine is synthesized by reaction. The prepared catalyst can promote the directional adsorption and activation of the carboxyl group of L-lysine, improve the selectivity, and efficiently synthesize pentanediamine.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of chemical synthesis, and particularly relates to a rare earth metal modified transition metal catalyst and a method for synthesizing pentanediamine catalyzed by the catalyst. BACKGROUND

[0002] Nylon 5X is a new polyamide material obtained by polymerizing pentanediamine and dibasic acid, and has excellent properties such as high moisture permeability and dryness rate, good wear resistance, and high strength, and is currently recognized as a substitute material for nylon 6X in the world. The technical core is the efficient synthesis of monomer 1,5-pentanediamine. The synthesis methods of pentanediamine mainly include biological fermentation method and chemical decarboxylation method. Companies such as Dupont, Invista and some domestic research teams have carried out related research on biological fermentation method. Tianjin University has carried out permeability treatment on Escherichia coli engineering bacteria with high yield of pentanediamine, and the yield of pentanediamine reaches 90%-100%(CN201911230411.9); Shanghai Kaisai Biotechnology Research and Development Center Co., Ltd. has applied for a plurality of patents for biological fermentation method of pentanediamine(CN201811506539.9, CN201710453415.8, CN201710011198.7, etc.), but the problems of low enzyme activity and unstable enzyme structure caused by the biological toxicity of pentanediamine have not been completely solved, which limits the development of pentanediamine synthesis technology. Compared with the biological fermentation decarboxylation method, the chemical decarboxylation method has the advantages of catalyst activity not affected by the toxicity of pentanediamine, catalyst can be reused, and product is easy to separate. However, the problem of low selectivity of chemical method still needs to be solved. The selectivity of L-lysine decarboxylation to synthesize pentanediamine on commercial Ru / C is the highest, which is 40%(ACS Sustainable Chemistry and Engineering, 2020, 8, 11805-11817); the highest selectivity of the Ru-Mn / Beta catalyst developed by the previous team is 54%(ACS Sustainable Chemistry and Engineering, 2021, 9, 13480-13490). SUMMARY

[0003] In order to solve the technical problem of low selectivity of chemical decarboxylation synthesis of pentanediamine, the present application provides a rare earth metal modified transition metal catalyst and a method for synthesizing pentanediamine catalyzed by the catalyst. The prepared catalyst can promote the directional adsorption and activation of the carboxyl group of L-lysine, improve the selectivity, and efficiently synthesize pentanediamine.

[0004] In order to achieve the above purpose, the technical scheme of the present application is as follows:

[0005] A rare earth metal modified transition metal catalyst, wherein the rare earth metal modified transition metal catalyst refers to the modification of a transition metal catalyst with rare earth metals; the transition metal catalyst is a transition metal supported molecular sieve, in which the transition metal is confined within the molecular sieve as a reactive center; after the rare earth metal modification, the molecular sieve support or framework is not affected, the reactive center of the transition metal remains unchanged, but the catalytic decarboxylation reaction performance is significantly improved.

[0006] The rare earth metal is any one or more of the following: lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), lutetium (Lu), scandium (Sc), and yttrium (Y).

[0007] The method for modifying transition metal catalysts using rare earth metals is ion exchange, impregnation, or in-situ synthesis.

[0008] The rare earth metal accounts for 0.01% to 30% of the mass fraction in the rare earth metal modified transition metal catalyst, preferably between 0.05% and 10%, and more preferably between 0.1% and 5%.

[0009] The transition metal-supported molecular sieve is synthesized through dynamic hydrothermal synthesis or crystalline hydrothermal synthesis.

[0010] The molecular sieve is any one of silica-alumina molecular sieve, phosphorus-alumina molecular sieve, and silica-phosphorus molecular sieve.

[0011] The transition metal in the reactive center is any one or more of palladium (Pd), platinum (Pt), chromium (Cr), lead (Pb), cobalt (Co), cadmium (Cd), iron (Fe), copper (Cu), niobium (Nb), manganese (Mn), nickel (Ni), and ruthenium (Ru).

[0012] The transition metal accounts for 0.1% to 50% of the mass fraction in the rare earth metal modified transition metal catalyst, preferably between 1% and 20%, and more preferably between 5% and 10%.

[0013] A method for synthesizing pentanediamine using a rare earth metal-modified transition metal catalyst involves mixing lysine or lysine salt, water, and the rare earth metal-modified transition metal catalyst to obtain a mixed solution, and then reacting to synthesize pentanediamine.

[0014] The lysine is L-lysine, and the lysine salt is any one of lysine hydrochloride, lysine sulfate, lysine acetate, and lysine phosphate.

[0015] The reaction conditions are as follows: reaction temperature 100–300℃, pressure 0.1–8 MPa, lysine or lysine salt concentration in the mixed solution 0.01–3 M, molar ratio of lysine or lysine salt to catalyst 1:(0.005–0.1); pH value of the mixed solution 1–8, reaction time 5–180 min, and reaction atmosphere any one of nitrogen, hydrogen, argon, helium, or carbon monoxide.

[0016] The beneficial effects of this invention: L-lysine molecules contain one carboxyl group and two amino groups, and their indiscriminate adsorption on the catalyst surface is a major cause of the formation of byproducts such as piperidine. Based on the above, this invention prepares a rare earth metal-modified transition metal catalyst. By introducing rare earth ions of hard Lewis acids, stable rare earth oxides are formed with oxygen on the catalyst framework, enhancing the basicity of the catalyst surface, promoting the directional adsorption and activation of the L-lysine carboxyl group, and efficiently synthesizing pentanediamine. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 XRD patterns of the FAU framework and part of the catalyst. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] I. Preparation of blank catalyst

[0021] 1. Preparation of Ru@FAU

[0022] 2.8 g of NaOH was completely dissolved in 25 mL of distilled water. 0.3375 g of sodium aluminate was added and stirred thoroughly. 12.68 g of silica sol was added dropwise to the resulting solution at room temperature. Then, 0.34 g of RuCl3·H2O was added, and the mixture was stirred at 600 rpm for 4 h. The mixture was then transferred to a stainless steel reactor and crystallized in a 100 °C oven for 15 h. After the reactor had completely cooled, the supernatant was removed. The resulting solid was washed with deionized water until neutral, dried, and ground to obtain the Ru@FAU catalyst.

[0023] 2. Preparation of Ni@FAU

[0024] 2.8 g of NaOH was completely dissolved in 25 mL of distilled water. 0.3375 g of sodium aluminate was added and stirred thoroughly. 12.68 g of silica sol was added dropwise to the resulting solution at room temperature. Then, 0.17 g of NiCl2 was added, and the mixture was stirred at 600 rpm for 4 hours. The mixture was then transferred to a stainless steel reactor and crystallized in a 100°C oven for 15 hours. After the reactor had completely cooled, the supernatant was removed. The resulting solid was washed with deionized water until neutral, dried, and ground to obtain the Ni@FAU catalyst.

[0025] 3. Preparation of Co@FAU

[0026] 2.8 g of NaOH was completely dissolved in 25 mL of distilled water. 0.3375 g of sodium aluminate was added and stirred thoroughly. 12.68 g of silica sol was added dropwise to the resulting solution at room temperature. Then, 0.31 g of CoCl₂ + H₂O was added, and the mixture was stirred at 600 rpm for 4 hours. The mixture was then transferred to a stainless steel reactor and crystallized in a 100°C oven for 15 hours. After the reactor had completely cooled, the supernatant was removed. The resulting solid was washed with deionized water until neutral, dried, and ground to obtain the Co@FAU catalyst.

[0027] 4. Preparation of Pd@FAU

[0028] 2.8 g of NaOH was completely dissolved in 25 mL of distilled water. 0.3375 g of sodium aluminate was added and stirred thoroughly. 12.68 g of silica sol was added dropwise to the resulting solution at room temperature. Then, 0.26 g of PdSO4 was added, and the mixture was stirred at 600 rpm for 4 hours. The mixture was then transferred to a stainless steel reactor and crystallized in a 100°C oven for 15 hours. After the reactor had completely cooled, the supernatant was removed. The resulting solid was washed with deionized water until neutral, dried, and ground to obtain the Pd@FAU catalyst.

[0029] In the specific embodiments described below, the transition metal catalysts used are selected from the above-mentioned types.

[0030] II. Derivation of the DEEMM method

[0031] The reaction system consisted of 600 μL borate buffer (50 mM, pH = 9), 200 μL methanol, 60 μL sample, 130 μL ultrapure water, and 10 μL 1 M diethyl ethoxymethylene malonate (DEEMM). After mixing, the mixture was placed at room temperature for 10 min, and then in a water bath at 70 °C for 2 h to obtain the derivatized product. III. Specific Implementation Examples

[0033] Blank comparison example

[0034] 1 mmol L-lysine hydrochloride, 0.101 g Ru@FAU catalyst, and 10 mL deionized water were placed in a 25 mL reactor liner. Phosphoric acid was added dropwise during stirring to adjust the pH to 2.0. The liner was placed in the reactor and sealed. The air inside the reactor was replaced with N2, followed by replacement of the N2 with high-purity H2. A final H2 atmosphere of 2 MPa was maintained. The reaction conditions were: temperature 200 °C, stirring speed 800 r / min, and quenching in a water bath after the reaction. The reaction time was 10 min. The resulting reaction solution was derivatized using the DEEMM method and analyzed by high-performance liquid chromatography (HPLC). The results showed that the concentration of pentanediamine in the reaction solution was 2.7 g / L, the lysine conversion rate was 66.7%, and the pentanediamine selectivity was 41.1%.

[0035] Example 1

[0036] This embodiment catalyzes the chemical decarboxylation of L-lysine hydrochloride to produce 1,5-pentanediamine. The catalyst used is water-insoluble CeO2 co-impregnated and modified Ru@FAU, i.e., 1 wt% CeO2-Ru@FAU. The steps are as follows:

[0037] (1) Preparation of 1wt% CeO2-Ru@FAU

[0038] CeO2 was selected as the impregnation source. Based on a certain amount of Ru@FAU, 1 wt% CeO2 was weighed and added to an appropriate amount of deionized water to obtain a paste-like mixture. The mixture was stirred evenly and allowed to stand for 12 hours. After drying at 100℃, the mixture was ground and placed in a muffle furnace. The temperature was increased to 400℃ at 5℃ / min, and calcined for 3 hours to obtain a 1 wt% CeO2-Ru@FAU catalyst.

[0039] (2) Reaction Evaluation

[0040] 1 mmol L-lysine hydrochloride, 0.101 g of 1 wt% CeO2-Ru@FAU catalyst, and 10 mL of deionized water were placed in a 25 mL reactor liner. Phosphoric acid was added dropwise during stirring to adjust the pH of the solution to 2.0. The liner was placed in the reactor and sealed. The air inside the reactor was replaced with N2, followed by replacement of the N2 with high-purity H2. A final H2 atmosphere of 2 MPa was maintained. The reaction conditions were: temperature 200 °C, stirring speed 800 r / min, and quenching in a water bath after the reaction. The reaction time was 25 min. The resulting reaction solution was derivatized using the DEEMM method and analyzed by high-performance liquid chromatography (HPLC). The results showed that the concentration of pentanediamine in the reaction solution was 5.1 g / L, the lysine conversion rate was 62.9%, and the pentanediamine selectivity was 80.7%.

[0041] Example 2

[0042] This embodiment catalyzes the chemical decarboxylation of L-lysine hydrochloride to produce 1,5-pentanediamine. The catalyst used is water-soluble CeN3O96H2O co-impregnated and modified Ru@FAU, i.e., 1 wt% Ce-Ru@FAU. The steps are as follows:

[0043] (1) Preparation of 1wt% Ce-Ru@FAU

[0044] CeN3O96H2O was selected as the impregnation source. Based on a certain amount of Ru@FAU, 1 wt% of CeN3O96H2O was weighed and added to an appropriate amount of deionized water to obtain a paste-like mixture. The mixture was stirred evenly and allowed to stand for 12 hours. After drying at 100℃, the mixture was ground and placed in a muffle furnace. The temperature was increased to 400℃ at a rate of 5℃ / min, and calcined for 3 hours to obtain a 1 wt% Ce-Ru@FAU catalyst.

[0045] (2) Reaction Evaluation

[0046] 1 mmol L-lysine hydrochloride, 0.101 g of 1 wt% Ce-Ru@FAU catalyst, and 10 mL of deionized water were placed in a 25 mL reactor liner. Phosphoric acid was added dropwise during stirring to adjust the pH to 2.0. The liner was placed in the reactor and sealed. The air inside the reactor was replaced with N2, followed by replacement of the N2 with high-purity H2. A final H2 atmosphere of 2 MPa was maintained. The reaction conditions were: temperature 200 °C, stirring speed 800 rpm, and quenching in a water bath after the reaction. The reaction time was 20 min. The resulting reaction solution was derivatized using the DEEMM method and analyzed by high-performance liquid chromatography (HPLC). The results showed that the concentration of pentanediamine in the reaction solution was 5.3 g / L, the lysine conversion rate was 68.0%, and the pentanediamine selectivity was 78.5%.

[0047] Example 3

[0048] This embodiment catalyzes the chemical decarboxylation of L-lysine hydrochloride to produce 1,5-pentanediamine. The catalyst used is water-soluble CeN3O96H2O co-impregnated and modified Ni@FAU, i.e., 1 wt% Ce-Ni@FAU. The steps are as follows:

[0049] (1) Preparation of 1wt% Ce-Ni@FAU

[0050] CeN3O96H2O was selected as the impregnation source. Based on a certain amount of Ni@FAU, 1 wt% of CeN3O96H2O was weighed and added to an appropriate amount of deionized water to obtain a paste-like mixture. The mixture was stirred evenly and allowed to stand for 12 hours. After drying at 100℃, the mixture was ground and placed in a muffle furnace. The temperature was increased to 400℃ at 5℃ / min, and calcined for 3 hours to obtain a 1 wt% Ce-Ni@FAU catalyst.

[0051] (2) Reaction Evaluation

[0052] 1 mmol L-lysine hydrochloride, 0.101 g of 1 wt% Ce-Ni@FAU catalyst, and 10 mL of deionized water were placed in a 25 mL reactor liner. Phosphoric acid was added dropwise during stirring to adjust the pH to 2.0. The liner was placed in the reactor and sealed. The air inside the reactor was replaced with N2, followed by replacement of the N2 with high-purity H2. A final H2 atmosphere of 2 MPa was maintained. The reaction conditions were: temperature 230 °C, stirring speed 800 r / min, and quenching in a water bath after the reaction. The reaction time was 25 min. The resulting reaction solution was derivatized using the DEEMM method and analyzed by high-performance liquid chromatography (HPLC). The results showed that the concentration of pentanediamine in the reaction solution was 5.2 g / L, the lysine conversion rate was 60.0%, and the pentanediamine selectivity was 86.5%.

[0053] Example 4

[0054] This embodiment catalyzes the chemical decarboxylation of L-lysine hydrochloride to produce 1,5-pentanediamine. The catalyst used is water-soluble CeN3O96H2O in-situ doped and modified Ru@FAU, named 1-1wt%Ce-Ru@FAU. The steps are as follows:

[0055] (1) Preparation of I-1wt% Ce-Ru@FAU

[0056] 2.8 g NaOH was completely dissolved in 25 mL distilled water. 0.3375 g sodium aluminate was added and stirred thoroughly. 12.68 g silica sol was added dropwise to the resulting solution at room temperature. Then, 0.022 g CeN₃O₉₆H₂O and 0.34 g RuCl₃³H₂O were added, and the mixture was stirred at 600 rpm for 4 h. The mixture was then transferred to a stainless steel reactor and crystallized in a 100 °C oven for 15 h. After the reactor had completely cooled, the supernatant was removed. The resulting solid was washed with deionized water until neutral, dried, ground, and then placed in a muffle furnace. The temperature was increased to 400 °C at 5 °C / min, and calcined for 3 h to obtain a 1-1 wt% Ce-Ru@FAU catalyst.

[0057] (2) Reaction Evaluation

[0058] 1 mmol L-lysine hydrochloride, 0.101 g of 1-1 wt% Ce-Ru@FAU catalyst, and 10 mL of deionized water were placed in a 25 mL reactor liner. Phosphoric acid was added dropwise during stirring to adjust the pH to 2.0. The liner was placed in the reactor and sealed. The air inside the reactor was replaced with N2, followed by replacement of the N2 with high-purity H2. A final H2 atmosphere of 2 MPa was maintained. The reaction conditions were: temperature 200 °C, stirring speed 800 r / min, and quenching in a water bath after the reaction. The reaction time was 20 min. The resulting reaction solution was derivatized using the DEEMM method and analyzed by high-performance liquid chromatography (HPLC). The results showed that the concentration of pentanediamine in the reaction solution was 8.4 g / L, the lysine conversion rate was 100%, and the pentanediamine selectivity was 83.9%.

[0059] Figure 1 The results showed that the characteristic peak of FAU crystal form in the catalyst obtained by co-impregnation with Ce was significantly reduced, indicating that the co-impregnation method had a significant impact on the catalyst. The characteristic peak of FAU crystal form in the catalyst obtained by in-situ doping with Ce was reduced compared to Ru@FAU, but significantly higher than that obtained by the co-impregnation method. This demonstrates that in-situ doping modification promotes more uniform dispersion of Ce in the FAU molecular sieve. Compared with Example 2, the reaction results of Example 4 showed that the lysine conversion reached 100% and the pentanediamine selectivity was 83.9%, both significantly higher than the results of Example 2 (conversion 68.0%, selectivity 78.5%). This indicates that the uniform dispersion of Ce in Ru@FAU is beneficial to the interaction between the rare earth metal Ce and the active center Ru and the molecular sieve framework FAU, promoting the adsorption of lysine, the activation of carboxyl groups, and the desorption of pentanediamine, thereby increasing the reaction rate. Therefore, under the same reaction time, the lysine conversion was increased to 100%, while further conversion of pentanediamine was reduced, resulting in a pentanediamine selectivity as high as 83.9%.

[0060] Example 5

[0061] This embodiment catalyzes the chemical decarboxylation of L-lysine hydrochloride to produce 1,5-pentanediamine. The catalyst used is water-soluble CeN3O96H2O co-impregnated and modified Ru@FAU, i.e., 3wt% Ce-Ru@FAU. The steps are as follows:

[0062] (1) Preparation of 3wt% Ce-Ru@FAU

[0063] CeN3O96H2O was selected as the impregnation source. Based on a certain amount of Ru@FAU, 3wt% of CeN3O96H2O was weighed and added to an appropriate amount of deionized water to obtain a paste-like mixture. The mixture was stirred evenly and allowed to stand for 12 hours. After drying at 100℃, the mixture was ground and placed in a muffle furnace. The temperature was increased to 400℃ at 5℃ / min, and calcined for 3 hours to obtain a 3wt% Ce-Ru@FAU catalyst.

[0064] (2) Reaction Evaluation

[0065] 1 mmol L-lysine hydrochloride, 0.101 g of 3 wt% Ce-Ru@FAU catalyst, and 10 mL of deionized water were placed in a 25 mL reactor liner. Phosphoric acid was added dropwise during stirring to adjust the pH to 2.0. The liner was placed in the reactor and sealed. The air inside the reactor was replaced with N2, followed by replacement of the N2 with high-purity H2. A final H2 atmosphere of 2 MPa was maintained. The reaction conditions were: temperature 200 °C, stirring speed 800 rpm, and quenching in a water bath after the reaction. The reaction time was 15 min. The resulting reaction solution was derivatized using the DEEMM method and analyzed by high-performance liquid chromatography (HPLC). The results showed that the concentration of pentanediamine in the reaction solution was 4.9 g / L, the lysine conversion rate was 58.4%, and the pentanediamine selectivity was 83.7%.

[0066] Example 6

[0067] This embodiment catalyzes the chemical decarboxylation of L-lysine hydrochloride to produce 1,5-pentanediamine. The catalyst used is water-soluble CeN3O96H2O in-situ doped and modified Co@FAU, i.e., 1-0.1wt% Ce-Co@FAU. The steps are as follows:

[0068] (1) Preparation of I-0.1wt% Ce-Co@FAU

[0069] 2.8 g NaOH was completely dissolved in 25 mL distilled water. 0.3375 g sodium aluminate was added and stirred thoroughly. 12.68 g silica sol was added dropwise to the resulting solution at room temperature. Then, 0.002 g CeN3O96H2O and 0.31 g CoCl26H2O were added respectively. After stirring at 600 rpm for 4 h, the mixture was transferred to a stainless steel reactor and crystallized in a 100 °C oven for 15 h. After the reactor had completely cooled, the supernatant was removed. The resulting solid was washed with deionized water until neutral, dried, ground, and then placed in a muffle furnace. The temperature was increased to 400 °C at 5 °C / min, and calcined for 3 h to obtain I-0.1 wt% Ce-Co@FAU catalyst.

[0070] (2) Reaction Evaluation

[0071] 1 mmol L-lysine hydrochloride, 0.101 g of I-0.1 wt% Ce-Co@FAU catalyst, and 10 mL of deionized water were placed in a 25 mL reactor liner. Phosphoric acid was added dropwise during stirring to adjust the pH to 3.0. The liner was placed in the reactor and sealed. The air inside the reactor was replaced with N2, followed by replacement of the N2 with high-purity H2. A final H2 atmosphere of 2 MPa was maintained. The reaction conditions were: temperature 200 °C, stirring speed 800 rpm, and quenching in a water bath after the reaction. The reaction time was 40 min. The resulting reaction solution was derivatized using the DEEMM method and analyzed by high-performance liquid chromatography (HPLC). The results showed that the concentration of pentanediamine in the reaction solution was 4.8 g / L, the lysine conversion rate was 55.3%, and the pentanediamine selectivity was 86.7%.

[0072] Example 7

[0073] This embodiment catalyzes the chemical decarboxylation of L-lysine hydrochloride to produce 1,5-pentanediamine. The catalyst used is water-soluble CeN3O96H2O in-situ doped and modified Ru@FAU, i.e., 1-0.1wt% Ce-Ru@FAU. The steps are as follows:

[0074] (1) Preparation of I-0.1wt% Ce-Ru@FAU

[0075] 2.8 g NaOH was completely dissolved in 25 mL distilled water. 0.3375 g sodium aluminate was added and stirred thoroughly. 12.68 g silica sol was added dropwise to the resulting solution at room temperature. Then, 0.002 g CeN₃O₉₆H₂O and 0.34 g RuCl₃³H₂O were added, and the mixture was stirred at 600 rpm for 4 h. The mixture was then transferred to a stainless steel reactor and crystallized in a 100 °C oven for 15 h. After the reactor had completely cooled, the supernatant was removed. The resulting solid was washed with deionized water until neutral, dried, ground, and then placed in a muffle furnace. The temperature was increased to 400 °C at 5 °C / min, and calcined for 3 h to obtain I-0.1 wt% Ce-Ru@FAU catalyst.

[0076] (2) Reaction Evaluation

[0077] 1 mmol L-lysine hydrochloride, 0.101 g of I-0.1 wt% Ce-Ru@FAU catalyst, and 10 mL of deionized water were placed in a 25 mL reactor liner. Phosphoric acid was added dropwise during stirring to adjust the pH to 2.0. The liner was placed in the reactor and sealed. The air inside the reactor was replaced with N2, followed by replacement of the N2 with high-purity H2. A final H2 atmosphere of 2 MPa was maintained. The reaction conditions were: temperature 200 °C, stirring speed 800 r / min, and quenching in a water bath after the reaction. The reaction time was 20 min. The resulting reaction solution was derivatized using the DEEMM method and analyzed by high-performance liquid chromatography (HPLC). The results showed that the concentration of pentanediamine in the reaction solution was 6.3 g / L, the lysine conversion rate was 73.1%, and the pentanediamine selectivity was 85.6%.

[0078] Example 8

[0079] This embodiment catalyzes the chemical decarboxylation of L-lysine hydrochloride to produce 1,5-pentanediamine. The catalyst used is water-soluble CeN3O96H2O in-situ doped and modified Ru@FAU, named 1-5wt%Ce-Ru@FAU. The steps are as follows:

[0080] (1) Preparation of I-5wt% Ce-Ru@FAU

[0081] 2.8 g NaOH was completely dissolved in 25 mL distilled water. 0.3375 g sodium aluminate was added and stirred thoroughly. 12.68 g silica sol was added dropwise to the resulting solution at room temperature. Then, 0.110 g CeN₃O₉₆H₂O and 0.34 g RuCl₃³H₂O were added, and the mixture was stirred at 600 rpm for 4 h. The mixture was then transferred to a stainless steel reactor and crystallized in a 100 °C oven for 15 h. After the reactor had completely cooled, the supernatant was removed. The resulting solid was washed with deionized water until neutral, dried, ground, and then placed in a muffle furnace. The temperature was increased to 400 °C at 5 °C / min, and calcined for 3 h to obtain a 1-5 wt% Ce-Ru@FAU catalyst.

[0082] (2) Reaction Evaluation

[0083] 1 mmol L-lysine hydrochloride, 0.101 g of I-5 wt% Ce-Ru@FAU catalyst, and 10 mL of deionized water were placed in a 25 mL reactor liner. Phosphoric acid was added dropwise during stirring to adjust the pH to 2.0. The liner was placed in the reactor and sealed. The air inside the reactor was replaced with N2, followed by replacement of the N2 with high-purity H2. A final H2 atmosphere of 2 MPa was maintained. The reaction conditions were: temperature 200 °C, stirring speed 800 r / min, and quenching in a water bath after the reaction. The reaction time was 20 min. The resulting reaction solution was derivatized using the DEEMM method and analyzed by high-performance liquid chromatography (HPLC). The results showed that the concentration of pentanediamine in the reaction solution was 5.5 g / L, the lysine conversion rate was 64.9%, and the pentanediamine selectivity was 84.3%.

[0084] Extending the reaction time further increases the lysine conversion rate. However, due to the high catalyst activity at this point, the product pentanediamine is an unstable substance that will further catalyze into byproducts such as piperidine, affecting the pentanediamine yield. Therefore, the reaction time is not extended further.

[0085] Example 9

[0086] This embodiment catalyzes the chemical decarboxylation of L-lysine hydrochloride to produce 1,5-pentanediamine. The catalyst used is water-soluble Sm(NO3)36H2O in-situ doped and modified Ru@MFI, i.e., 1-1wt% Sm-Ru@FAU. The steps are as follows:

[0087] (1) Preparation of I-1wt% Sm-Ru@MFI

[0088] 4.04 g NaOH was completely dissolved in 135 mL distilled water. 1.65 g sodium aluminate was added and stirred thoroughly. 104 g silica sol was added dropwise to the resulting solution at room temperature. Then, 0.021 g Sm(NO3)3·6H2O and 0.45 g RuCl3·3H2O were added, and the mixture was stirred at 600 rpm for 4 h. The resulting mixture was then aged at 200 rpm for 24 h. Afterward, the mixture was transferred to a stainless steel reactor and crystallized in an oven at 180 °C for 24 h. Once the reactor had completely cooled, the supernatant was removed. The resulting solid was washed with deionized water until neutral, dried, and ground to obtain a 1-1 wt% Sm-Ru@MFI catalyst.

[0089] (2) Reaction Evaluation

[0090] 1 mmol L-lysine hydrochloride, 0.101 g of 1-1 wt% Sm-Ru@MFI catalyst, and 10 mL of deionized water were placed in a 25 mL reactor liner. Phosphoric acid was added dropwise during stirring to adjust the pH of the solution to 1.5. The liner was placed in the reactor and sealed. The air inside the reactor was replaced with N2, followed by replacement of the N2 with high-purity H2. A final H2 atmosphere of 3 MPa was maintained. The reaction conditions were: temperature 200 °C, stirring speed 800 r / min, and quenching in a water bath after the reaction. The reaction time was 20 min. The resulting reaction solution was derivatized using the DEEMM method and analyzed by high-performance liquid chromatography (HPLC). The results showed that the concentration of pentanediamine in the reaction solution was 5.2 g / L, the lysine conversion rate was 68.4%, and the pentanediamine selectivity was 75.3%.

[0091] Example 10

[0092] This embodiment catalyzes the chemical decarboxylation of L-lysine hydrochloride to produce 1,5-pentanediamine. The catalyst used is water-soluble La(NO3)36H2O in-situ doped and modified Ru@FAU, i.e., 1-1wt% La-Ru@FAU. The steps are as follows:

[0093] (1) Preparation of I-1wt% La-Ru@FAU

[0094] 2.8 g NaOH was completely dissolved in 25 mL distilled water. 0.3375 g sodium aluminate was added and stirred thoroughly. 12.68 g silica sol was added dropwise to the resulting solution at room temperature. Then, 0.021 g La(NO3)36H2O and 0.34 g RuCl33H2O were added respectively. After stirring at 600 rpm for 4 h, the mixture was transferred to a stainless steel reactor and crystallized in a 100 °C oven for 15 h. After the reactor had completely cooled, the supernatant was removed. The resulting solid was washed with deionized water until neutral, dried, ground, and then placed in a muffle furnace. The temperature was increased to 400 °C at 5 °C / min, and calcined for 3 h to obtain 1-1 wt% La-Ru@FAU catalyst.

[0095] (2) Reaction Evaluation

[0096] 5 mmol of L-lysine sulfate, 0.101 g of 1-1 wt% La-Ru@FAU catalyst, and 10 mL of deionized water were placed in a 25 mL reactor liner. Phosphoric acid was added dropwise during stirring to adjust the pH to 2.5. The liner was placed in the reactor and sealed. The air inside the reactor was replaced with N2, followed by replacement of the N2 with high-purity H2. A final H2 atmosphere of 3 MPa was maintained. The reaction conditions were: temperature 240 °C, stirring speed 800 rpm, and quenching in a water bath after the reaction. The reaction time was 150 min. The resulting reaction solution was derivatized using the DEEMM method and analyzed by high-performance liquid chromatography (HPLC). The results showed that the concentration of pentanediamine in the reaction solution was 26.1 g / L, the lysine conversion rate was 94.1%, and the pentanediamine selectivity was 55.4%.

[0097] Example 11

[0098] This embodiment catalyzes the chemical decarboxylation of L-lysine hydrochloride to produce 1,5-pentanediamine. The catalyst used is water-soluble Pr(NO3)36H2O in-situ doped and modified Pd@FAU, i.e., 1-1wt% Pr-Pd@FAU. The steps are as follows:

[0099] (1) Preparation of I-1wt%Pr-Pd@FAU

[0100] 2.8 g NaOH was completely dissolved in 25 mL distilled water. 0.3375 g sodium aluminate was added and stirred thoroughly. 12.68 g silica sol was added dropwise to the resulting solution at room temperature. Then, 0.021 g Pr(NO3)36H2O and 0.26 g PdSO4 were added, and the mixture was stirred at 600 rpm for 4 h. The mixture was then transferred to a stainless steel reactor and crystallized in a 100 °C oven for 15 h. After the reactor had completely cooled, the supernatant was removed. The resulting solid was washed with deionized water until neutral, dried, ground, and then placed in a muffle furnace. The temperature was increased to 400 °C at 5 °C / min, and calcined for 3 h to obtain a 1-1 wt% Pr-Pd@FAU catalyst.

[0101] (2) Reaction Evaluation

[0102] 1 mmol L-lysine hydrochloride, 0.101 g of I-1 wt% Pr-Pd@FAU catalyst, and 10 mL of deionized water were placed in a 25 mL reactor liner. Phosphoric acid was added dropwise during stirring to adjust the pH to 2.5. The liner was placed in the reactor and sealed. The air inside the reactor was replaced with N2, followed by replacement of the N2 with high-purity H2. A final H2 atmosphere of 3 MPa was maintained. The reaction conditions were: temperature 200 °C, stirring speed 800 r / min, and quenching in a water bath after the reaction. The reaction time was 25 min. The resulting reaction solution was derivatized using the DEEMM method and analyzed by high-performance liquid chromatography (HPLC). The results showed that the concentration of pentanediamine in the reaction solution was 5.7 g / L, the lysine conversion rate was 66.3%, and the pentanediamine selectivity was 86.7%.

[0103] Example 12

[0104] This embodiment catalyzes the chemical decarboxylation of L-lysine hydrochloride to produce 1,5-pentanediamine. The catalyst used is water-soluble Pr(NO3)36H2O in-situ doped and modified Pd@FAU, i.e., 1-0.1wt% Pr-Pd@FAU. The steps are as follows:

[0105] (1) Preparation of I-0.1wt% Pr-Pd@FAU

[0106] 2.8 g NaOH was completely dissolved in 25 mL distilled water. 0.3375 g sodium aluminate was added and stirred thoroughly. 12.68 g silica sol was added dropwise to the resulting solution at room temperature. Then, 0.0021 g Pr(NO3)36H2O and 0.26 g PdSO4 were added, and the mixture was stirred at 600 rpm for 4 h. The mixture was then transferred to a stainless steel reactor and crystallized in a 100 °C oven for 15 h. After the reactor had completely cooled, the supernatant was removed. The resulting solid was washed with deionized water until neutral, dried, ground, and then placed in a muffle furnace. The temperature was increased to 400 °C at 5 °C / min, and calcined for 3 h to obtain I-0.1 wt% Pr-Pd@FAU catalyst.

[0107] (2) Reaction Evaluation

[0108] 1 mmol L-lysine hydrochloride, 0.101 g of I-0.1 wt% Pr-Pd@FAU catalyst, and 10 mL of deionized water were placed in a 25 mL reactor liner. Phosphoric acid was added dropwise during stirring to adjust the pH of the solution to 1. The liner was placed in the reactor and sealed. The air inside the reactor was replaced with N2, followed by replacement of the N2 with high-purity H2. A final H2 atmosphere of 8 MPa was maintained. The reaction conditions were: temperature 300 °C, stirring speed 800 r / min, and quenching in a water bath after the reaction. The reaction time was 5 min. The resulting reaction solution was derivatized using the DEEMM method and analyzed by high-performance liquid chromatography (HPLC). The results showed that the concentration of pentanediamine in the reaction solution was 2.6 g / L, the lysine conversion rate was 29.6%, and the pentanediamine selectivity was 88.7%.

[0109] Example 13

[0110] This embodiment catalyzes the chemical decarboxylation of L-lysine hydrochloride to produce 1,5-pentanediamine. The catalyst used is water-soluble CeN3O96H2O co-impregnated and modified Pd@FAU, i.e., 10wt% Ce-Pd@FAU. The steps are as follows:

[0111] (1) Preparation of 10wt% Ce-Pd@FAU

[0112] CeN3O96H2O was selected as the impregnation source. Based on a certain amount of Pd@FAU, 10wt% of CeN3O96H2O was weighed and added to an appropriate amount of deionized water to obtain a paste-like mixture. The mixture was stirred evenly and allowed to stand for 12 hours. After drying at 100℃, the mixture was ground and placed in a muffle furnace. The temperature was increased to 400℃ at 5℃ / min, and calcined for 3 hours to obtain a 10wt% Ce-Pd@FAU catalyst.

[0113] (2) Reaction Evaluation

[0114] 1 mmol L-lysine hydrochloride, 0.101 g of 10 wt% Ce-Pd@FAU catalyst, and 10 mL of deionized water were placed in a 25 mL reactor liner. Phosphoric acid was added dropwise during stirring to adjust the pH to 8.0. The liner was placed in the reactor and sealed. The air inside the reactor was replaced with N2, followed by replacement of the N2 with high-purity H2. A final H2 atmosphere of 0.1 MPa was maintained. The reaction conditions were: temperature 100 °C, stirring speed 800 r / min, and quenching in a water bath after the reaction. The reaction time was 180 min. The resulting reaction solution was derivatized using the DEEMM method and analyzed by high-performance liquid chromatography (HPLC). The results showed that the concentration of pentanediamine in the reaction solution was 4.5 g / L, the lysine conversion rate was 100%, and the pentanediamine selectivity was 45.3%.

Claims

1. A method for synthesizing pentanediamine catalyzed by a rare earth metal-modified transition metal catalyst, characterized in that, A mixed solution was prepared by mixing lysine or lysine salt, water, and a rare earth metal-modified transition metal catalyst, and then reacted to synthesize pentanediamine. The rare earth metal modified transition metal catalyst refers to the modification of transition metal catalysts with rare earth metals; the transition metal catalyst is a transition metal supported molecular sieve, in which the transition metal is confined within the molecular sieve as a reactive center; after the rare earth metal modification, the molecular sieve support or framework is not affected, and the reactive centers of the transition metal remain unchanged. The rare earth metal is any one or more of lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium, scandium, and yttrium; The transition metal in the reactive center is any one or more of palladium, platinum, chromium, lead, cobalt, cadmium, iron, copper, niobium, manganese, nickel, or ruthenium.

2. The method for synthesizing pentanediamine catalyzed by a rare earth metal-modified transition metal catalyst according to claim 1, characterized in that, The lysine is L-lysine, and the lysine salt is any one of lysine hydrochloride, lysine sulfate, lysine acetate, and lysine phosphate.

3. The method for synthesizing pentanediamine catalyzed by a rare earth metal-modified transition metal catalyst according to claim 2, characterized in that, The reaction conditions are as follows: reaction temperature 100~300℃, pressure 0.1~8 MPa, lysine or lysine salt concentration in the mixed solution 0.01~3M, pH value of the mixed solution 1~8, reaction time 5~180 min, and reaction atmosphere is hydrogen.

4. The method for synthesizing pentanediamine catalyzed by a rare earth metal-modified transition metal catalyst according to claim 1, characterized in that, The method for modifying transition metal catalysts using rare earth metals is ion exchange, impregnation, or in-situ synthesis.

5. The method for synthesizing pentanediamine catalyzed by a rare earth metal-modified transition metal catalyst according to claim 4, characterized in that, The rare earth metal accounts for 0.01% to 30% of the mass fraction in the rare earth metal modified transition metal catalyst.

6. The method for synthesizing pentanediamine catalyzed by a rare earth metal-modified transition metal catalyst according to claim 5, characterized in that, The molecular sieve is any one of silica-alumina molecular sieve, phosphorus-alumina molecular sieve, or silica-phosphorus molecular sieve.

7. The method for synthesizing pentanediamine catalyzed by a rare earth metal-modified transition metal catalyst according to claim 6, characterized in that, The transition metal accounts for 0.1% to 50% of the mass fraction in the rare earth metal modified transition metal catalyst.

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