Monatomic doped co / ceria interface catalyst and preparation method and application thereof in preparation of c5 / c6 linear polyol

Abstract

The present application relates to single-atom doped Co / CeO2 interface catalyst and preparation method and application thereof in C5 / C6 straight-chain polyol preparation; the catalyst is represented as M SA Co / CeO2, the loading amount of Co is 10 wt%-30 wt% of the total mass of the catalyst; M is a doped single atom including Pt, Ru, Pd and Rh, and the doping amount is 0.2-1.0 wt%. The present application adopts a single reaction system one-step catalysis strategy, and in the same reactor, without separating or purifying the intermediate product, the continuous hydrogenation, deoxidation, selective ring-opening and further hydrogenation and other multi-step reaction processes of the furan platform compound from biomass can be realized, and finally the target C5 / C6 straight-chain polyol product is directly obtained. Since the catalyst has excellent catalytic activity and target product selectivity, the straight-chain alcohol yield can be significantly improved, and the side reactions such as excessive hydrogenation, condensation and cracking can be effectively inhibited, and high-purity target product can be obtained without complex intermediate separation and purification process, the process flow is simple, and has good industrial application prospect.

Description

Technical Field

[0001] This invention belongs to the field of industrial catalysis and bioenergy conversion technology, specifically relating to a single-atom-doped Co / CeO2 interfacial catalyst, its preparation method, and its application in the selective ring-opening preparation of C5 / C6 linear polyols from biomass furan platform compounds. Background Technology

[0002] The production of high-value-added chemicals from renewable resources such as lignocellulose and biomass sugars has become an important research direction in green chemistry and sustainable development. Among these, furan platform compounds, such as furfural (FF), furfuryl alcohol (FOL), 5-hydroxymethylfurfural (HMF), and 2,5-bis(hydroxymethyl)furan (BHMF), can be efficiently prepared from hemicellulose, cellulose, and sugar biomass, serving as crucial platform molecules connecting renewable biomass resources with high-value chemicals. Through catalytic hydrogenation and selective ring-opening reactions, these furan platform compounds can be further converted into high-value-added chemicals such as linear monools and polyols, providing an important technological pathway for the high-value utilization of biomass resources.

[0003] Linear-chain C5 / C6 polyols, such as 1,5-pentanediol, 1,2-pentanediol, 1,2-hexanediol, 1,5-hexanediol, 2,5-hexanediol, and 1,2,6-hexanetriol, are important fine chemicals and chemical intermediates with wide applications in polyesters, polyurethanes, biodegradable polymers, pharmaceuticals, fragrances, surfactants, and high-performance solvents. Therefore, developing efficient catalytic systems to achieve highly selective conversion of biomass-derived furan platform compounds into linear-chain C5 / C6 polyols has significant scientific and industrial application value.

[0004] Currently, the hydrogenation ring-opening reaction of furan platform compounds mainly relies on supported metal catalysts, non-noble metal catalysts, and bimetallic catalyst systems. Among them, noble metals such as Pt, Ru, Pd, and Rh possess excellent hydrogen activation capabilities and high hydrogenation reactivity, effectively promoting the hydrogenation conversion of carbonyl groups and unsaturated structures in furan platform compounds. However, traditional supported noble metal catalytic systems are typically composed of metal nanoparticles or clusters, whose surfaces expose various coordination environments and active sites with different electronic structures, making it difficult to precisely control reactant adsorption, hydrogen activation, and key intermediate conversion processes. In the hydrogenation conversion of furan platform molecules, excessively strong metal-hydrogen interactions often promote the preferential saturation of the furan ring to form tetrahydrofuran derivatives or induce multiple competing reaction pathways, thus limiting the ability to control the selective cleavage of the C–O bond of the furan ring and the formation of linear alcohol products. In contrast, non-noble metal catalysts such as Co, Ni, and Cu have attracted attention in the field of biomass platform molecule conversion due to their low cost, abundant reserves, and certain C–O bond activation capabilities. However, due to their weak hydrogen dissociation activation ability, high reaction temperatures and hydrogen pressures are usually required for effective conversion. Furthermore, their limited ability to regulate active sites means that the selectivity of the target linear polyol product still needs improvement. Bimetallic catalysts offer a new strategy for regulating the ring-opening hydrogenation reaction of biomass molecules through electronic effects and synergistic interactions between different metal components. For example, combining noble metals with transition metals can, to some extent, balance hydrogen activation and oxygen-containing functional group conversion capabilities. However, traditional bimetallic catalysts typically exist in the form of alloy particles or nanoparticles, making it difficult to precisely control the metal size, composition, and interface structure. This results in unclear true active sites, insufficient synergistic effects between metals, and problems such as metal migration, aggregation, and activity decay during the reaction. Therefore, how to construct metal active centers with well-defined interface structures and tunable electronic properties to achieve synergistic regulation of hydrogen activation, selective cleavage of the furan ring C–O bond, and product desorption remains a key problem to be solved in this field.

[0005] In recent years, single-atom catalysts have shown promising applications in hydrogenation, selective oxidation, and biomass catalytic conversion due to their near 100% atomic utilization, uniform and well-defined coordination structures, and excellent tunable electronic structures. However, single-atom catalysts typically lack continuous metal sites, limiting their catalytic performance in complex reactions involving multi-site synergistic adsorption, intermediate migration, and C–O bond breaking. Therefore, constructing novel interfacial catalytic structures that synergistically integrate single atoms and metal clusters, fully leveraging the advantages of highly efficient hydrogen activation by single atoms and the C–O bond breaking promoted by metal clusters, holds promise for significantly improving the selective hydrogenation and ring-opening reaction performance of furan platform compounds. Furthermore, the catalyst support not only affects the dispersion state of metal species but also directly determines the metal-support interaction and interfacial electronic structure. CeO2 possesses excellent oxygen storage / release capacity and abundant oxygen vacancies, effectively stabilizing highly dispersed metal active sites and promoting active hydrogen migration and interfacial electronic regulation, demonstrating significant advantages in biomass catalytic conversion. However, there is still a lack of effective catalyst design strategies for constructing stable single-atom-metal cluster interface structures using CeO2 supports to achieve synergistic regulation of hydrogen activation, hydrogen spillover migration, and selective ring opening of furan rings.

[0006] Therefore, developing a novel interfacial catalyst with a well-defined interface structure, combining efficient hydrogen activation and selective ring-opening capabilities of furan rings, to achieve the efficient and directional conversion of furan platform compounds from various biomass sources into straight-chain C5 / C6 polyols, is of great significance for promoting the high-value utilization of biomass resources and the manufacture of green chemicals. Summary of the Invention

[0007] To address the problems in existing technologies for the selective hydrogenation and ring-opening of biomass-derived furan platform compounds, such as insufficient hydrogen activation, difficulty in selectively breaking the C–O bond of the furan ring, low selectivity for target straight-chain alcohols, poor catalyst stability, and low utilization of precious metals, this invention provides a single-atom-doped Co / CeO2 interfacial catalyst, its preparation method, and its application in the selective hydrogenation and ring-opening of biomass-derived furan platform compounds to prepare straight-chain C5 / C6 polyols. Through the synergistic effect of the atomic-scale interface between the doped single-atom metal and the Co cluster, hydrogen dissociation and directional migration of active hydrogen are promoted, while simultaneously stabilizing Co. 2+ By identifying oxygen vacancy active sites, optimizing the adsorption configuration of key intermediates, and lowering the ring-opening energy barrier of the furan ring C–O bond, excessive hydrogenation of the furan ring and side reactions are effectively suppressed, thereby improving the selectivity, catalytic activity, and stability of the target product. This enables the efficient and targeted conversion of various biomass-derived furan platform compounds into straight-chain C5 / C6 alcohols.

[0008] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0009] A single-atom-doped Co / CeO2 interfacial catalyst, with M SA Co / CeO2 represents (where M) SA sub-mark SA The Co loading is 10 wt% to 30 wt% of the total catalyst mass (representing the interface). M is a doped single atom including Pt, Ru, Pd, and Rh, with a doping amount of 0.2 to 1.0 wt%, preferably 0.5 wt%. Both the loading and doping amounts are calculated based on the total mass of the final catalyst. In the catalyst, M is stably anchored at the Co / CeO2 interface as an oxygen-coordinated single atom, forming M–Co–O with neighboring Co clusters. v Interfacial synergistic active sites do not form metal nanoparticles.

[0010] The method for preparing the single-atom-doped Co / CeO2 interfacial catalyst of the present invention includes the following steps:

[0011] 1) Using cobalt nitrate hexahydrate as the mass standard, the mass ratio of cerium nitrate hexahydrate, cobalt nitrate hexahydrate and polyvinylpyrrolidone (K30) is controlled at 1.6-2.4:1:0.4-1.2 and added to ethylene glycol solvent. The mixture is stirred at room temperature to form a homogeneous solution.

[0012] The ethylene glycol has a purity of not less than 99.8%, and the total concentration of metal salts in the mixed solution is 0.02–0.10 mol / L.

[0013] 2) At room temperature, continuously stir at a speed of 400–500 rpm while adding deionized water to the above mixed solution to obtain a homogeneous and transparent solution; the volume ratio of deionized water to ethylene glycol is 1:5–1:8, and stirring continues for 0.5–2 hours.

[0014] 3) Transfer the mixed solution to a stainless steel hydrothermal reactor, cover the reactor, tighten the steel sleeve, and then heat it in a rotary oven at 140-160 ℃ for 20-24 h;

[0015] 4) The obtained solid product was washed 5 to 7 times by centrifugation with ethanol to remove unreacted substances and organic residues, and then dried at 60 to 100 °C for 10 to 20 h to obtain the Co / CeO2 precursor.

[0016] 5) The noble metal precursor solution is added to the Co / CeO2 precursor using an equal-volume impregnation method. The noble metal precursor is selected from sodium hexachloroplatinate, ruthenium trichloride, palladium chloride, or rhodium trichloride. The volume of the noble metal precursor solution is equal to the pore volume of the Co / CeO2 precursor, ensuring uniform penetration of the noble metal precursor into the pores and surface of the Co / CeO2 precursor.

[0017] 6) The impregnated precursor was dried and then calcined in air in a muffle furnace to obtain M. SA Co / CeO2 precursor

[0018] 7) Finally, the obtained precursor was placed in a 5% (v / v) H2 / N2 mixed atmosphere and reduced at 350–400 °C to obtain the M single-atom doped Co / CeO2 interfacial catalyst, denoted as M. SA Co / CeO2. M is highly dispersed in the Co / CeO2 interface in the form of single atoms, and Co species are loaded on the CeO2 surface in the form of nanoclusters, forming an atomic-level noble metal single atom-metal nanocluster-oxide carrier interface structure.

[0019] In the preparation method of the single-atom doped Co / CeO2 interfacial catalyst, the stirring conditions after adding deionized water in step (1) are 400-500 rpm and the time is 0.5-1.5 h.

[0020] In the preparation method of the single-atom doped Co / CeO2 interfacial catalyst, the calcination temperature in step (6) is 450-550 ℃ and the calcination time is 2-3h.

[0021] In the method for preparing the single-atom doped Co / CeO2 interfacial catalyst, the reducing atmosphere in step (7) is a 5% hydrogen / nitrogen mixed gas, and the reduction time is 3-5 h.

[0022] The application of the single-atom-doped Co / CeO2 interfacial catalyst of the present invention in the selective hydrogenation and ring-opening of biomass-derived furan platform compounds to prepare C5 / C6 straight-chain alcohols includes the following steps:

[0023] a) The single-atom-doped Co / CeO2 interfacial catalyst, furan platform compound substrate, and reaction solvent are added to a high-pressure reactor and thoroughly mixed. After sealing the reactor, the air inside is replaced with hydrogen, and hydrogen is introduced to a pressure of 2–4 MPa. The catalyst is M. SA The Co / CeO2 interfacial catalyst, wherein M is selected from one or more of Pt, Ru, Pd, and Rh, and the amount of the catalyst is 1 wt% to 20 wt% of the substrate. The concentration of the substrate in the reaction is 0.05 to 2 mol / L.

[0024] b) Heat the reactor to 120-180 °C and start stirring. The reaction time is 1-8 h. After the reaction is completed, stop stirring, cool to room temperature, then depressurize and open the reactor to separate the liquid products and catalyst.

[0025] The biomass-derived furan platform compounds include one or more of the following furan derivatives: furfural, furfuryl alcohol, tetrahydrofurfuryl alcohol, 2-methylfuran, 2-methyltetrahydrofuran, 5-hydroxymethylfurfural, 2,5-dihydroxymethylfuran, 2,5-dihydroxymethyltetrahydrofuran, 2,5-dimethylfuran, 2,5-dimethyltetrahydrofuran, 5-methylfurfural, and 5-methylfurfuryl alcohol.

[0026] The linear polyols include: 1,2-pentanediol, 1,5-pentanediol, 1,2-hexanediol, 1,5-hexanediol, 2,5-hexanediol, 1,2,6-hexanetriol, and mixtures thereof.

[0027] The solvent used in the application reaction is isopropanol, and the mass ratio of the catalyst to the substrate is 1:0.82-1.32.

[0028] The specific explanation is as follows:

[0029] In the single-atom doped Co / CeO2 catalyst of this invention, metal M is highly dispersed in single-atom form. Through strong interactions with the Co and CeO2 interfaces, it regulates the electronic structure of the Co active center and the oxygen vacancy distribution on the CeO2 surface, constructing an interfacial catalytic center with highly efficient hydrogen activation and selective C–O bond activation and breaking capabilities. This enables the efficient and selective hydrogenation and ring-opening of biomass-derived furan platform compounds to prepare C5 / C6 linear polyols. The reaction equation is as follows:

[0030] Co(NO3)2 + Ce(NO3)3 → CoO x / CeO2

[0031] M n+ / CoO x / CeO2→M SA Co / CeO2

[0032] M = Pt, Ru, Pd, Rh (SA is a single atom)

[0033] This invention employs a method that involves performing multiple reaction steps simultaneously in the same reaction vessel without separating or purifying intermediate products, ultimately directly generating the target product. The specific details are as follows.

[0034] This invention employs a one-step catalytic strategy in a single reaction system, enabling a multi-step reaction process in a single reactor, including continuous hydrogenation, deoxygenation, selective ring-opening, and further hydrogenation of biomass-derived furan platform compounds, without the need for separation or purification of intermediate products. The final product is the target C5 / C6 linear polyol. After the reaction, the catalyst and liquid product are separated by filtration. The liquid product can be directly analyzed qualitatively and quantitatively using methods such as GC, GC-MS, HPLC, and NMR. Due to the excellent catalytic activity and target product selectivity of the catalyst, this invention significantly improves the yield of linear alcohols and effectively suppresses side reactions such as over-hydrogenation, condensation, and cracking. High-purity target products can be obtained without complex intermediate separation and purification processes. The process is simple and has promising prospects for industrial application.

[0035] This invention introduces M single atoms at the Co / CeO2 interface to synergistically regulate the Co active sites and CeO2 interface oxygen vacancies, thereby stably anchoring the doped metal single atoms at the Co–CeO2 interface and inducing electronic structure reconstruction of the Co active sites and oxygen vacancy formation, thus constructing an M–Co–O with a well-defined interface structure. v Synergistic active centers. Among them, Pt single atoms maintain a highly dispersed state through strong metal-support interactions, while simultaneously regulating the electronic environment and interfacial electron distribution of Co, enhancing the selective activation ability of Co active sites for the C–O bond of the furan ring, and improving the stability and number of oxygen vacancies, thereby promoting interfacial electron transfer and active hydrogen migration.

[0036] Under the aforementioned regulatory mechanism, the introduction of the M single atom can efficiently dissociate and activate hydrogen, generating active hydrogen species and regulating the electronic structure reconstruction of the Co active site and increasing the number of oxygen vacancies. The Co active site is conducive to the adsorption and selective activation of furan rings and oxygen-containing functional groups in furan platform compounds. Interfacial oxygen vacancies further promote substrate adsorption, key intermediate stabilization, and active hydrogen spillover migration. The three work synergistically to achieve efficient coupling of multiple key reaction steps, such as hydrogen activation, active hydrogen migration, selective ring opening of furan rings, and subsequent hydrogenation. This enables the efficient and targeted conversion of various biomass-derived furan platform compounds, such as furfural, furfuryl alcohol, 5-hydroxymethylfurfural, and 2,5-dihydroxymethylfuran, into 1,5-pentanediol, 1,2-pentanediol, 1,2,6-hexanetriol, and other C5 / C6 straight-chain polyols in a single reaction system.

[0037] The significant advantages of this invention are:

[0038] 1) This invention introduces a single M atom at the Co / CeO2 interface, thereby achieving synergistic regulation of the electronic structure of the Co active center and the oxygen vacancies at the interface, and constructing an M–Co–O with a well-defined structure. vThe interface is a synergistic active center. This interface can fully leverage the synergistic advantages of noble metal single atoms efficiently activating hydrogen, Co active sites selectively activating furan ring C–O bonds, and oxygen vacancies promoting substrate adsorption and active hydrogen migration, effectively improving the catalytic efficiency of selective hydrogenation ring-opening reactions of biomass-derived furan platform compounds.

[0039] 2) The catalyst of this invention is applicable to a variety of biomass-derived furan platform compounds, including furfural, furfuryl alcohol, tetrahydrofurfuryl alcohol, 5-hydroxymethylfurfural, 2,5-dihydroxymethylfuran and other furan derivatives. It can achieve efficient and selective hydrogenation ring-opening under relatively mild reaction conditions to prepare 1,5-pentanediol, 1,2-pentanediol, 1,2,6-hexanetriol and other C5 / C6 straight-chain polyols. It has a wide range of substrate applications and excellent target product selectivity.

[0040] 3) The catalyst of this invention adopts a single-atom doping strategy of M, which significantly reduces the amount of M used while maintaining excellent catalytic performance and improves the utilization rate of noble metal atoms. At the same time, the strong interaction between the single M atom and the Co and CeO2 interfaces effectively stabilizes the active structure, inhibits the migration and aggregation of M and the sintering of Co species, so that the catalyst has good structural stability and recycling performance, and still maintains good stability after 10 cycles.

[0041] 4) This invention adopts a one-step catalytic strategy to continuously complete multiple key reaction steps such as substrate hydrogenation, selective ring opening of furan ring, and further hydrogenation in the same reaction system. There is no need for intermediate product separation or purification. The reaction process is simple, with few side reactions and high atom utilization, and it has good process economy and industrial scale-up application potential.

[0042] 5) This invention achieves highly efficient coupling of multiple reaction processes, including hydrogen activation, active hydrogen spillover, key intermediate stabilization, and selective C–O bond breaking, through the synergistic regulation of the Co active center and interfacial oxygen vacancies by the M single atom. This provides a universal interfacial catalytic strategy for the high-value conversion of biomass-derived furan platform compounds and can offer new catalyst design ideas for the selective catalytic conversion of other biomass platform molecules. Attached Figure Description

[0043] Figure 1 Pt as described in Example 1 0.5 A schematic diagram of the Co / CeO2 catalyst preparation process and characterization results using aberration-corrected scanning transmission electron microscopy (AC-STEM). Among them: Figure 1 a is Pt 0.5 The schematic diagram of the Co / CeO2 catalyst preparation process shows the process of Co / CeO2 precursor construction, Pt precursor introduction, heat treatment and reduction to form Pt single-atom interface catalyst. Figure 1b is an AC-STEM image of the catalyst obtained in Example 1, where bright areas represent Pt species signals with higher atomic numbers, and gray areas correspond to the Co / CeO2 support region. Figure 1 b. It can be observed that no obvious Pt particle aggregation occurs on the catalyst surface, and the Pt species are highly dispersed. Figure 1 c and 1d are AC-STEM images of the catalyst at higher magnification, showing that Pt species are uniformly dispersed in the Co / CeO2 interface region. Figure 1 e represents the line scan intensity analysis result of the Pt single-atom region, further proving that Pt exists stably in single-atom form.

[0044] Figure 2 Pt as described in Example 1 SA X-ray photoelectron spectroscopy (XPS) analysis results of Pt 4f in fresh samples and samples after 10 cycles of reaction of Co / CeO2 catalyst. Different colored curves represent the Pt 4f spectra of the fresh catalyst and the catalyst after recycling, respectively. The horizontal axis represents the binding energy, and the vertical axis represents the photoelectron intensity. As shown in the figure, the position and shape of the Pt 4f peak remain basically consistent before and after the cyclic reaction, and no obvious Pt species migration or aggregation is observed, indicating that the Pt single-atom structure has good stability during the reaction.

[0045] Figure 3 This is the result of elemental mapping analysis using scanning transmission electron microscopy for the sample in Example 1. Different color regions correspond to the signal intensities of the respective elements. Figure 3 a, b, c, and d correspond to the distribution of Co, Ce, O, and Pt elements, respectively. Figure 3 a is a distribution map of Co element, with the green area representing Co element; Figure 3 b is a distribution map of Ce element, where the yellow area represents Ce element; Figure 3 c is the distribution map of O element, and the red area in the map represents oxygen element; Figure 3 Figure d shows the distribution of Pt elements, with the purple area representing Pt. As can be seen from the figure, Co, Ce, and O elements are uniformly distributed in the catalyst particles, while Pt elements are highly dispersed. No obvious Pt particle aggregation was observed, indicating that Pt was successfully anchored at the Co / CeO2 interface, forming a uniformly distributed Pt–Co–CeO2 interface structure.

[0046] Figure 4 The results are obtained from inductively coupled plasma (ICP) analysis of different Pt-doped samples in Examples 1 and 5-7. Figure 4 Columns 1 to 4 correspond to Pt respectively 0.5 / Co / CeO2、Pt 0.2 / Co / CeO2、Pt 0.8 / Co / CeO2 and Pt 1.0 The actual Pt doping amount in the / Co / CeO2 catalyst was determined. The results show that the Pt content in the catalyst gradually increases with increasing theoretical Pt doping, indicating that the Pt doping process has good controllability.

[0047] Figure 5 The Pt sample described in Example 1 SA Density functional theory (DFT) calculation results for Co / CeO2 catalysts. Among them, Figure 5 a represents the catalyst model before the introduction of a single Pt atom. Figure 5 b represents the Bader charge analysis results of each element in the catalyst model after the introduction of a Pt single atom. The introduction of the Pt single atom alters the charge distribution of Co and neighboring Ce and O atoms, resulting in significant electronic modulation of the interface region. This indicates a strong electronic interaction between Pt and Co / CeO2, which can effectively regulate the electronic structure of the active center. Figure 5 c is the charge density difference diagram after the introduction of Pt single atoms. The yellow area represents the electron accumulation region, and the blue area represents the electron depletion region, indicating that the Pt single atom induces significant electron transfer in the interfacial region, which is beneficial for regulating reactant adsorption and C–O bond activation. This shows that the introduction of Pt single atoms induces interfacial electron redistribution, promotes electronic coupling between Pt–Co–CeO2, facilitates the construction of interfacial active centers with synergistic catalytic effects, and further regulates the adsorption of furan platform compounds and the C–O bond activation process.

[0048] Figure 6 The X-ray absorption spectra (XAS) analysis results of Pt L3 edge samples and standard samples from Example 1 are shown. Different color curves correspond to Pt... 0.5 Co / CeO2 samples, Pt foil, and PtO2 standard samples. The EXAFS spectra after Fourier transform show that Pt... 0.5 No obvious Pt–Pt scattering peaks were observed in the / Co / CeO2 sample, but Pt–O and Pt–Co coordination characteristics were mainly observed. This indicates that Pt species exist in the form of single atoms and form a stable coordination structure with neighboring Co and oxygen species, which further proves the formation of the Pt single atom and Co / CeO2 interface structure.

[0049] Figure 7 The different Pt doping amounts described in Examples 1, 5-7, and 9 SA XPS analysis results of Co2p in the Co / CeO2 catalyst. Different color peaks in the figure correspond to different cobalt species components. As shown in the figure, the electronic state of the Co species changes significantly after the introduction of Pt. 2+ / Co 3+The regulation of the ratio and electronic environment indicates that there is an electronic interaction between the Pt single atom and the Co active center, which is beneficial to regulating the catalytic performance of the Co site.

[0050] Figure 8 The figures show the O 1s X-ray photoelectron spectroscopy (XPS) analysis results of different Pt-doped Co / CeO2 catalysts described in Examples 1, 5-7, and 8. Different color peaks in the figures correspond to different oxygen species compositions. As can be seen from the figures, compared with the Co / CeO2 catalyst without Pt, the introduction of Pt single atoms significantly changes the proportion of defective oxygen on the catalyst surface, indicating a strong interaction between Pt species and the CeO2 support, which can regulate the formation and stabilization of oxygen vacancies on the CeO2 surface. The construction of oxygen vacancies not only promotes the stable anchoring of Pt single atoms but also enhances the interfacial electron transfer capability, optimizing the adsorption and activation process of reactants at the Pt–Co–CeO2 interface.

[0051] Figure 9 The Pt described in Examples 1 and 8 0.5 Raman spectral analysis results of Co / CeO2 and Co / CeO2 catalysts. As shown in the figure, the lattice vibration peaks of CeO2 changed after the introduction of Pt, while the intensity of the defect-related peaks increased. This indicates that the introduction of Pt single atoms promoted the formation of lattice defects in CeO2 and increased the oxygen vacancy concentration, further demonstrating that Pt has a regulatory effect on the interface structure.

[0052] Figure 10 Pt as described in Examples 1 and 8 0.5 Electron paramagnetic resonance (EPR) analysis results of Co / CeO2 and Co / CeO2 catalysts. As shown in the figure, Pt... 0.5 The / Co / CeO2 catalyst exhibits a significant oxygen vacancy-related signal, indicating that the introduction of Pt single atoms promotes the formation of surface defect structures on CeO2, thereby constructing an interfacial catalytic system with abundant oxygen vacancies. Detailed Implementation

[0053] To make the content of this invention easier to understand, the technical solution of this invention will be further described below with reference to specific embodiments, but this invention is not limited thereto.

[0054] Example 1

[0055] 1. Weigh 2.5 g of cerium nitrate hexahydrate, 1.235 g of cobalt nitrate hexahydrate and 1 g of polyvinylpyrrolidone (K30) and dissolve them in 70 mL of ethanol and stir to form a mixed solution.

[0056] 2. At room temperature, with stirring (400 rpm), slowly add 10 ml of deionized water to the mixed solution. Continue stirring at room temperature for 0.5 h.

[0057] 3. Transfer the mixed solution to a 100 mL hydrothermal reactor, cover the reactor, tighten the steel sleeve, and then heat in a rotary oven at 160 °C for 24 h;

[0058] 4. After washing five times with ethanol by centrifugation, a brownish-yellow solid was obtained, which was then dried at 80 °C overnight.

[0059] 5. Impregnate an equal volume of 0.018 g of sodium platinum hexahydrate into the dried Co / CeO2 precursor.

[0060] 6. Subsequently, the catalyst precursor was obtained by calcining at 500 °C for 3 h in a nitrogen and hydrogen atmosphere at a heating frequency of 2 °C / min.

[0061] 7. Finally, the obtained precursor was placed in a 5% H2 / N2 mixture and reduced at 400℃ for 3 h to obtain Pt. 0.5 Co / CeO2 catalyst.

[0062] Figure 4 Column 2 has a Pt loading of 0.573% in Example 1.

[0063] Example 2

[0064] 1. Weigh 2.4 g of cerium nitrate hexahydrate, 1.15 g of cobalt nitrate hexahydrate and 0.85 g of polyvinylpyrrolidone (K30) and dissolve them in 80 mL of ethanol and stir to form a mixed solution.

[0065] 2. At room temperature, with stirring (400 rpm), slowly add 10 ml of deionized water to the mixed solution. Continue stirring at room temperature for 0.5 h.

[0066] 3. Transfer the mixed solution to a 100 mL hydrothermal reactor, cover the reactor, tighten the steel sleeve, and then heat in a rotary oven at 150 °C for 24 h;

[0067] 4. After washing five times with ethanol by centrifugation, a brown solid was obtained, which was then dried at 80 °C overnight.

[0068] 5. Impregnate an equal volume of 0.0162 g of ruthenium trichloride trihydrate into the dried CeO2 precursor.

[0069] 6. Subsequently, the catalyst precursor was obtained by calcining at 500 °C for 3 h in a nitrogen and hydrogen atmosphere at a heating frequency of 2 °C / min.

[0070] 7. Finally, the obtained precursor was placed in a 5% H2 / N2 mixture and reduced at 400℃ for 3 h to obtain Ru. 0.5 / CeO2 catalyst.

[0071] Example 3

[0072] 1. Weigh 1.93 g of cerium nitrate hexahydrate, 0.72 g of cobalt nitrate hexahydrate, and 0.65 g of polyvinylpyrrolidone (K30) and dissolve them in 90 mL of ethanol and stir to form a mixed solution.

[0073] 2. At room temperature, with stirring (400 rpm), slowly add 10 ml of deionized water to the mixed solution. Continue stirring at room temperature for 0.5 h.

[0074] 3. Transfer the mixed solution to a 100 mL hydrothermal reactor, cover the reactor, tighten the steel sleeve, and then heat in a rotary oven at 140 °C for 24 h;

[0075] 4. After washing five times with ethanol by centrifugation, a brown solid was obtained, which was then dried at 80 °C overnight.

[0076] 5. Impregnate an equal volume of 0.0125 g of palladium chloride dihydrate into the dried CeO2 precursor.

[0077] 6. Subsequently, the catalyst precursor was obtained by calcining at 500 °C for 3 h in a nitrogen and hydrogen atmosphere at a heating frequency of 2 °C / min.

[0078] 7. Finally, the obtained precursor was placed in a 5% H2 / N2 mixture and reduced at 400℃ for 3 h to obtain Pd. 0.5 / CeO2 catalyst.

[0079] Example 4

[0080] 1. Weigh 3.2 g of cerium nitrate hexahydrate, 2 g of cobalt nitrate hexahydrate, and 1.8 g of polyvinylpyrrolidone (K30) and dissolve them in 90 mL of ethanol and stir to form a mixed solution.

[0081] 2. At room temperature, with stirring (400 rpm), slowly add 10 ml of deionized water to the mixed solution. Continue stirring at room temperature for 0.5 h.

[0082] 3. Transfer the mixed solution to a 100 mL hydrothermal reactor, cover the reactor, tighten the steel sleeve, and then heat in a rotary oven at 180 °C for 24 h;

[0083] 4. After washing five times with ethanol by centrifugation, a brown solid was obtained, which was then dried at 80 °C overnight.

[0084] 5. Impregnate an equal volume of 0.0160 g of rhodium trichloride trihydrate into the dried CeO2 precursor.

[0085] 6. Subsequently, the catalyst precursor was obtained by calcining at 500 °C for 3 h in a nitrogen and hydrogen atmosphere at a heating frequency of 2 °C / min.

[0086] 7. Finally, the obtained precursor was placed in a 5% H2 / N2 mixture and reduced at 400℃ for 3 h to obtain Rh. 0.5 / CeO2 catalyst.

[0087] Example 5

[0088] 1. Weigh 2.5 g of cerium nitrate hexahydrate, 1.235 g of cobalt nitrate hexahydrate and 1 g of polyvinylpyrrolidone (K30) and dissolve them in 80 mL of ethanol and stir to form a mixed solution.

[0089] 2. At room temperature, with stirring (450 rpm), slowly add 10 ml of deionized water to the mixed solution. Continue stirring at room temperature for 0.5 h.

[0090] 3. Transfer the mixed solution to a 100 mL hydrothermal reactor, cover the reactor, tighten the steel sleeve, and then heat in a rotary oven at 140 °C for 24 h;

[0091] 4. After washing five times with ethanol by centrifugation, a brown solid was obtained, which was then dried at 80 °C overnight.

[0092] 5. Impregnate an equal volume of 0.0072 g of sodium platinum hexahydrate into the dried Co / CeO2 precursor.

[0093] 6. Subsequently, the catalyst precursor was obtained by calcining at 500 °C for 3 h in a nitrogen and hydrogen atmosphere at a heating frequency of 2 °C / min.

[0094] 7. Finally, the obtained precursor was placed in a 5% H2 / N2 mixture and reduced at 400℃ for 3 h to obtain Pt. 0.2 Co / CeO2 catalyst.

[0095] Figure 4 Column 1 represents the load of Pt in Example 2, which is 0.284%.

[0096] Example 6

[0097] 1. Weigh 2.5 g of cerium nitrate hexahydrate, 1.235 g of cobalt nitrate hexahydrate and 1 g of polyvinylpyrrolidone (K30) and dissolve them in 90 mL of ethanol and stir to form a mixed solution.

[0098] 2. At room temperature, with stirring (500 rpm), slowly add 10 ml of deionized water to the mixed solution. Continue stirring at room temperature for 0.5 h.

[0099] 3. Transfer the mixed solution to a 100 mL hydrothermal reactor, cover the reactor, tighten the steel sleeve, and then heat in a rotary oven at 180 °C for 24 h;

[0100] 4. After washing five times with ethanol by centrifugation, a brown solid was obtained, which was then dried at 80 °C overnight.

[0101] 5. Impregnate an equal volume of 0.0288 g of sodium platinum hexahydrate into the dried Co / CeO2 precursor.

[0102] 6. Subsequently, the catalyst precursor was obtained by calcining at 500 °C for 3 h in a nitrogen and hydrogen atmosphere at a heating frequency of 2 °C / min.

[0103] 7. Finally, the obtained precursor was placed in a 5% H2 / N2 mixture and reduced at 400℃ for 3 h to obtain Pt. 0.8 Co / CeO2 catalyst.

[0104] Figure 7 Column 3 represents the load of Pt in Example 3, which is 0.877%.

[0105] Example 7

[0106] 1. Weigh 2.5 g of cerium nitrate hexahydrate, 1.235 g of cobalt nitrate hexahydrate and 1 g of polyvinylpyrrolidone (K30) and dissolve them in 100 mL of ethanol and stir to form a mixed solution.

[0107] 2. At room temperature, with stirring (500 rpm), slowly add 10 ml of deionized water to the mixed solution. Continue stirring at room temperature for 0.5 h.

[0108] 3. Transfer the mixed solution to a 100 mL hydrothermal reactor, cover the reactor, tighten the steel sleeve, and then heat in a rotary oven at 180 °C for 24 h;

[0109] 4. After washing five times with ethanol by centrifugation, a brown solid was obtained, which was then dried at 80 °C overnight.

[0110] 5. Impregnate an equal volume of 0.036 g of sodium platinum hexahydrate into the dried Co / CeO2 precursor.

[0111] 6. Subsequently, the catalyst precursor was obtained by calcining at 500 °C for 3 h in a nitrogen and hydrogen atmosphere at a heating frequency of 2 °C / min.

[0112] 7. Finally, the obtained precursor was placed in a 5% H2 / N2 mixture and reduced at 400℃ for 3 h to obtain Pt. 1.0 Co / CeO2 catalyst.

[0113] Figure 4 Column 4 represents the load of Pt in Example 4, which is 1.134%.

[0114] Example 8

[0115] 1. Weigh 2.5 g of cerium nitrate hexahydrate and 1.235 g of cobalt nitrate hexahydrate and dissolve them in 70 mL of ethanol and stir to form a mixed solution.

[0116] 2. At room temperature, with stirring (450 rpm), slowly add 10 ml of deionized water to the mixed solution. Continue stirring at room temperature for 0.5 h.

[0117] 3. Transfer the mixed solution to a 100 mL hydrothermal reactor, cover the reactor, tighten the steel sleeve, and then heat in a rotary oven at 160 °C for 24 h;

[0118] 4. After washing five times with ethanol by centrifugation, a brown solid was obtained, which was then dried at 80 °C overnight.

[0119] 5. Subsequently, the catalyst precursor was obtained by calcining at 500 °C for 3 h in a nitrogen and hydrogen atmosphere at a heating frequency of 2 °C / min.

[0120] 6. Finally, the obtained precursor was placed in a 5% H2 / N2 mixture and reduced at 400℃ for 3 h to obtain the Co / CeO2 catalyst for use with Pt. 0.5 Comparison of Co / CeO2 catalysts.

[0121] Example 9

[0122] 1. Weigh 2.5 g of cerium nitrate hexahydrate and 1 g of polyvinylpyrrolidone (K30) and dissolve them in 70 mL of ethanol and stir to form a mixed solution.

[0123] 2. At room temperature, with stirring (400 rpm), slowly add 10 ml of deionized water to the mixed solution. Continue stirring at room temperature for 0.5 h.

[0124] 3. Transfer the mixed solution to a 100 mL hydrothermal reactor, cover the reactor, tighten the steel sleeve, and then heat in a rotary oven at 160 °C for 24 h;

[0125] 4. After washing five times with ethanol by centrifugation, a brown solid was obtained, which was then dried at 80 °C overnight.

[0126] 5. Impregnate an equal volume of 0.018 g of sodium platinum hexahydrate into the dried CeO2 precursor.

[0127] 6. Subsequently, the catalyst precursor was obtained by calcining at 500 °C for 3 h in a nitrogen and hydrogen atmosphere at a heating frequency of 2 °C / min.

[0128] 7. Finally, the obtained precursor was placed in a 5% H2 / N2 mixture and reduced at 400℃ for 3 h to obtain Pt. 0.5 / CeO2 catalyst is used with Pt 0.5 Comparison of Co / CeO2 catalysts.

[0129] Application: The single-atom modified Co / CeO2 interfacial catalyst described in this invention can be used to catalyze the hydrogenation and ring-opening of furan platform compounds to prepare C5 / C6 linear polyols. Based on the molecular structure characteristics of the furan platform compounds and the type of target product, M with different noble metal single-atom components is selected. SA The catalytic reaction is carried out using a Co / CeO2 catalyst. For 5-hydroxymethylfurfural (HMF) containing aldehyde and hydroxymethyl functional groups, a Pt single-atom modified Co / CeO2 catalyst with strong hydrogen activation and C–O bond selective activation is preferred to promote carbonyl hydrogenation, furan ring opening, and continuous hydrogenation processes, thereby achieving the formation of 1,2,6-hexanetriol. For furfural compounds containing aldehyde groups, Pt, Pd, or other noble metal single-atom modified Co / CeO2 catalysts can promote furan ring C–O bond breaking and hydrogenation reconstruction, achieving the preparation of C5 straight-chain diols such as 1,5-pentanediol. The noble metal single-atom component M is selected from one or more of Pt, Ru, Pd, and Rh. The introduction of different noble metal single atoms can regulate the electronic structure, hydrogen activation capacity, and substrate adsorption performance of the Co / CeO2 interface, thereby achieving the regulation of the conversion pathway of different furan platform compounds.

[0130] Example 10

[0131] Ring-opening reaction of furfural

[0132] a) Take 0.1 g of Pt obtained according to Example 1 SA Co / CeO2 catalyst and 10 mL of isopropanol solution containing 0.096 g furfural and 0.213 g n-dodecane were added to a high-temperature and high-pressure reactor.

[0133] b) Replace the air in the reactor with hydrogen three times, then fill the reactor with hydrogen until the initial pressure is 3MPa, raise the temperature to 160 ℃, stir at 500 r / min, and react for 2 h.

[0134] c) After the reaction is complete, stop stirring and cool to room temperature. Then, release the pressure and open the vessel to separate the liquid product and catalyst. Use mass spectrometry-gas chromatography to perform qualitative and quantitative analysis on the liquid product and calculate the substrate conversion rate, 1,5-pentanediol and C5 linear polyol yield.

[0135] The reaction results are shown in Table 1.

[0136] Table 1. Pt SA Results of Co / CeO2 catalytic furfural conversion

[0137]

[0138] Example 11

[0139] Ring-opening reaction of furfural

[0140] a) Take 0.1 g of Pd obtained according to Example 3 SA Co / CeO2 catalyst and 10 mL of isopropanol solution containing 0.096 g furfural and 0.213 g n-dodecane were added to a high-temperature and high-pressure reactor.

[0141] b) Replace the air in the reactor with hydrogen three times, then fill the reactor with hydrogen until the initial pressure is 3MPa, raise the temperature to 160 ℃, stir at 500 r / min, and react for 2 h.

[0142] c) After the reaction is complete, stop stirring and cool to room temperature. Then, release the pressure and open the vessel to separate the liquid product and catalyst. Use mass spectrometry-gas chromatography to perform qualitative and quantitative analysis on the liquid product and calculate the substrate conversion rate, 1,5-pentanediol and C5 linear polyol yield.

[0143] The reaction results are shown in Table 2.

[0144] Table 2. Pd SA Results of Co / CeO2 catalytic furfural conversion

[0145]

[0146] Example 12

[0147] Ring-opening reaction of furfuryl alcohol

[0148] a) Take 0.1 g of Pt obtained according to Example 1 SA Co / CeO2 catalyst and 10 mL of isopropanol solution containing 0.098 g furfuryl alcohol and 0.213 g n-dodecane were added to a high-temperature and high-pressure reactor.

[0149] b) Replace the air in the reactor with hydrogen three times, then fill the reactor with hydrogen until the initial pressure is 3MPa, raise the temperature to 160 ℃, stir at a rate of 550 r / min, and react for 1 h.

[0150] c) After the reaction is complete, stop stirring and cool to room temperature. Then, release the pressure and open the vessel to separate the liquid product and catalyst. Use mass spectrometry-gas chromatography to perform qualitative and quantitative analysis on the liquid product and calculate the substrate conversion rate, 1,5-pentanediol and C5 linear polyol yield.

[0151] The reaction results are shown in Table 3.

[0152] Table 3. Pt SA Results of Co / CeO2 catalytic conversion of furfuryl alcohol

[0153]

[0154] Example 13

[0155] Ring-opening reaction of furfuryl alcohol

[0156] a) Take 0.1 g of Rh obtained according to Example 4 SA Co / CeO2 catalyst and 10 mL of isopropanol solution containing 0.098 g furfuryl alcohol and 0.213 g n-dodecane were added to a high-temperature and high-pressure reactor.

[0157] b) Replace the air in the reactor with hydrogen three times, then fill the reactor with hydrogen until the initial pressure is 3MPa, raise the temperature to 160 ℃, stir at a rate of 550 r / min, and react for 1 h.

[0158] c) After the reaction is complete, stop stirring and cool to room temperature. Then, release the pressure and open the vessel to separate the liquid product and catalyst. Use mass spectrometry-gas chromatography to perform qualitative and quantitative analysis on the liquid product and calculate the substrate conversion rate, 1,5-pentanediol and C5 linear polyol yield.

[0159] The reaction results are shown in Table 4.

[0160] Table 4. Rh SA Results of Co / CeO2 catalytic conversion of furfuryl alcohol

[0161]

[0162] Example 14

[0163] Tetrahydrofurfuryl alcohol ring-opening reaction

[0164] a) Take 0.1 g of Pt obtained according to Example 7 SACo / CeO2 catalyst and 10 mL of isopropanol solution containing 0.102 g tetrahydrofurfuryl alcohol and 0.213 g n-dodecane were added to a high-temperature and high-pressure reactor.

[0165] b) Replace the air in the reactor with hydrogen three times, then fill the reactor with hydrogen until the initial pressure is 3 MPa, raise the temperature to 180 ℃, stir at a rate of 550 r / min, and react for 8 h.

[0166] c) After the reaction is complete, stop stirring and cool to room temperature. Then, release the pressure and open the vessel to separate the liquid product and catalyst. Use mass spectrometry-gas chromatography to perform qualitative and quantitative analysis on the liquid product and calculate the substrate conversion rate and 1,5-pentanediol yield.

[0167] The reaction results are shown in Table 5.

[0168] Table 5. Pt SA Results of Co / CeO2-catalyzed tetrahydrofurfuryl conversion

[0169]

[0170] Example 15

[0171] Ring-opening reaction of 2-methylfuran

[0172] a) Take 0.1 g of Pt obtained according to Example 6 SA Co / CeO2 catalyst and 10 mL of isopropanol solution containing 0.082 g 2-methylfuran and 0.213 g n-dodecane were added to a high-temperature and high-pressure reactor;

[0173] b) Replace the air in the reactor with hydrogen three times, then fill the reactor with hydrogen until the initial pressure is 3 MPa, raise the temperature to 140 ℃, stir at 550 r / min, and react for 2 h.

[0174] c) After the reaction is complete, stop stirring and cool to room temperature. Then, release the pressure and open the vessel to separate the liquid product and catalyst. Use mass spectrometry-gas chromatography to perform qualitative and quantitative analysis on the liquid product and calculate the substrate conversion rate and C5 linear polyol yield.

[0175] The reaction results are shown in Table 6.

[0176] Table 6. Pt SA Results of Co / CeO2-catalyzed 2-methylfuran conversion

[0177]

[0178] Example 16

[0179] Ring-opening reaction of 2-methyltetrahydrofuran

[0180] a) Take 0.1 g of Pt obtained according to Example 1 SA Co / CeO2 catalyst and 10 mL of isopropanol solution containing 0.086 g 2-methyltetrahydrofuran and 0.213 g n-dodecane were added to a high-temperature and high-pressure reactor;

[0181] b) Replace the air in the reactor with hydrogen three times, then fill the reactor with hydrogen until the initial pressure is 3 MPa, raise the temperature to 170 °C, stir at 550 r / min, and react for 7 h.

[0182] c) After the reaction is complete, stop stirring and cool to room temperature. Then, release the pressure and open the vessel to separate the liquid product and catalyst. Use mass spectrometry-gas chromatography to perform qualitative and quantitative analysis on the liquid product and calculate the substrate conversion rate and C5 linear polyol yield.

[0183] The reaction results are shown in Table 7.

[0184] Table 7. Pt SA Results of Co / CeO2 catalytic conversion of 2-methyltetrahydrofuran

[0185]

[0186] Example 17

[0187] 5-Hydroxymethylfurfural bond cleavage and ring-opening reaction

[0188] a) Take 0.1 g of Pt obtained according to Example 1 SA Co / CeO2 catalyst and 10 mL of isopropanol solution containing 0.126 g 5-hydroxymethylfurfural and 0.213 g n-dodecane were added to a high-temperature and high-pressure reactor.

[0189] b) Replace the air in the reactor with hydrogen three times, then fill the reactor with hydrogen until the initial pressure is 3 MPa, raise the temperature to 140℃, stir at 500 r / min, and react for 4 h.

[0190] c) After the reaction was complete, stirring was stopped and the mixture was cooled to room temperature. Then, the pressure was released and the reactor was opened. The liquid product and catalyst were separated. The liquid product was qualitatively and quantitatively analyzed using mass spectrometry-gas chromatography-mass spectrometry, and the substrate conversion and 1,2,6-hexanetriol yield were calculated. The reaction results are shown in Table 8.

[0191] Table 8. Pt SA Results of Co / CeO2-catalyzed conversion of 5-hydroxymethylfurfural

[0192]

[0193] Example 18

[0194] 5-Hydroxymethylfurfural bond cleavage and ring-opening reaction

[0195] a) Take 0.1 g of Ru obtained according to Example 2 SA Co / CeO2 catalyst and 10 mL of isopropanol solution containing 0.126 g 5-hydroxymethylfurfural and 0.213 g n-dodecane were added to a high-temperature and high-pressure reactor.

[0196] b) Replace the air in the reactor with hydrogen three times, then fill the reactor with hydrogen until the initial pressure is 3 MPa, raise the temperature to 140℃, stir at 500 r / min, and react for 4 h.

[0197] c) After the reaction was complete, stirring was stopped and the mixture was cooled to room temperature. Then, the pressure was released and the reactor was opened. The liquid product and catalyst were separated. The liquid product was analyzed qualitatively and quantitatively using mass spectrometry-gas chromatography-mass spectrometry, and the substrate conversion and 1,2,6-hexanetriol yield were calculated. The reaction results are shown in Table 9.

[0198] Table 9. Ru SA Results of Co / CeO2-catalyzed conversion of 5-hydroxymethylfurfural

[0199]

[0200] Example 19

[0201] 5-Hydroxymethylfurfural bond cleavage and ring-opening reaction

[0202] a) Take 0.1 g of Pd obtained according to Example 3 SA Co / CeO2 catalyst and 10 mL of isopropanol solution containing 0.126 g 5-hydroxymethylfurfural and 0.213 g n-dodecane were added to a high-temperature and high-pressure reactor.

[0203] b) Replace the air in the reactor with hydrogen three times, then fill the reactor with hydrogen until the initial pressure is 3 MPa, raise the temperature to 140℃, stir at 500 r / min, and react for 4 h.

[0204] c) After the reaction was complete, stirring was stopped and the mixture was cooled to room temperature. Then, the pressure was released and the reactor was opened. The liquid product and catalyst were separated. The liquid product was qualitatively and quantitatively analyzed using mass spectrometry-gas chromatography-mass spectrometry, and the substrate conversion and 1,2,6-hexanetriol yield were calculated. The reaction results are shown in Table 10.

[0205] Table 10. Pd SA Results of Co / CeO2-catalyzed conversion of 5-hydroxymethylfurfural

[0206]

[0207] Example 20

[0208] 5-Hydroxymethylfurfural bond cleavage and ring-opening reaction

[0209] a) Take 0.1 g of Rh obtained according to Example 4 SA Co / CeO2 catalyst and 10 mL of isopropanol solution containing 0.126 g 5-hydroxymethylfurfural and 0.213 g n-dodecane were added to a high-temperature and high-pressure reactor.

[0210] b) Replace the air in the reactor with hydrogen three times, then fill the reactor with hydrogen until the initial pressure is 3 MPa, raise the temperature to 140℃, stir at 500 r / min, and react for 4 h.

[0211] c) After the reaction was complete, stirring was stopped and the mixture was cooled to room temperature. Then, the pressure was released and the reactor was opened. The liquid product and catalyst were separated. The liquid product was analyzed qualitatively and quantitatively using mass spectrometry-gas chromatography-mass spectrometry, and the substrate conversion and 1,2,6-hexanetriol yield were calculated. The reaction results are shown in Table 11.

[0212] Table 11. Rh SA Results of Co / CeO2-catalyzed conversion of 5-hydroxymethylfurfural

[0213]

[0214] Example 21

[0215] 2,5-Dihydroxymethylfuran ring-opening reaction

[0216] a) Take 0.1 g of Pt obtained according to Example 5 SA Co / CeO2 catalyst and 10 mL of isopropanol solution containing 0.128 g 2,5-dihydroxymethylfuran and 0.213 g n-dodecane were added to a high-temperature and high-pressure reactor.

[0217] b) Replace the air in the reactor with hydrogen three times, then fill the reactor with hydrogen until the initial pressure is 3 MPa, raise the temperature to 150°C, stir at 500 r / min, and react for 4 h.

[0218] c) After the reaction was complete, stirring was stopped and the mixture was cooled to room temperature. Then, the pressure was released and the reactor was opened. The liquid product and catalyst were separated. The liquid product was analyzed qualitatively and quantitatively using mass spectrometry-gas chromatography-mass spectrometry, and the substrate conversion and 1,2,6-hexanetriol yield were calculated. The reaction results are shown in Table 12.

[0219] Table 12. Pt SA Results of Co / CeO2-catalyzed conversion of 2,5-dihydroxymethylfuran

[0220]

[0221] Example 22

[0222] 2,5-Dihydroxymethyltetrahydrofuran ring-opening reaction

[0223] a) Take 0.1 g of Pt obtained according to Example 5 SA Co / CeO2 catalyst and 10 mL of isopropanol solution containing 0.132 g 2,5-dihydroxymethylfuran and 0.213 g n-dodecane were added to a high-temperature and high-pressure reactor.

[0224] b) Replace the air in the reactor with hydrogen three times, then fill the reactor with hydrogen until the initial pressure is 3 MPa, raise the temperature to 180℃, stir at a rate of 500 r / min, and react for 5 h.

[0225] c) After the reaction was complete, stirring was stopped and the mixture was cooled to room temperature. Then, the pressure was released and the reactor was opened. The liquid product and catalyst were separated. The liquid product was analyzed qualitatively and quantitatively using mass spectrometry-gas chromatography-mass spectrometry, and the substrate conversion and 1,2,6-hexanetriol yield were calculated. The reaction results are shown in Table 13.

[0226] Table 13. Pt SA Results of Co / CeO2 catalytic conversion of 2,5-dihydroxymethyltetrahydrofuran

[0227]

[0228] Example 23

[0229] 2,5-Dimethylfuran ring-opening reaction

[0230] a) Take 0.1 g of Pt obtained according to Example 1 SA Co / CeO2 catalyst and 10 mL of isopropanol solution containing 0.098 g 2,5-dimethylfuran and 0.213 g n-dodecane were added to a high-temperature and high-pressure reactor.

[0231] b) Replace the air in the reactor with hydrogen three times, then fill the reactor with hydrogen until the initial pressure is 3 MPa, raise the temperature to 150°C, stir at 500 r / min, and react for 4 hours.

[0232] c) After the reaction is complete, stop stirring and cool to room temperature. Then, release the pressure and open the vessel to separate the liquid product and catalyst. Use mass spectrometry-gas chromatography to perform qualitative and quantitative analysis on the liquid product and calculate the substrate conversion rate and the yield of C6 linear polyol.

[0233] The reaction results are shown in Table 14.

[0234] Table 14. Pt SAResults of Co / CeO2 catalytic conversion of 2,5-dimethylfuran

[0235]

[0236] Example 24

[0237] 2,5-Dimethyltetrahydrofuran ring-opening reaction

[0238] a) Take 0.1 g of Pt obtained according to Example 1 SA Co / CeO2 catalyst and 10 mL of isopropanol solution containing 0.101 g 2,5-dimethyltetrahydrofuran and 0.213 g n-dodecane were added to a high-temperature and high-pressure reactor.

[0239] b) Replace the air in the reactor with hydrogen three times, then fill the reactor with hydrogen until the initial pressure is 4 MPa, raise the temperature to 180℃, stir at a rate of 500 r / min, and react for 5 h.

[0240] c) After the reaction is complete, stop stirring and cool to room temperature. Then, release the pressure and open the vessel to separate the liquid product and catalyst. Use mass spectrometry-gas chromatography to perform qualitative and quantitative analysis on the liquid product and calculate the substrate conversion rate and the yield of C6 linear polyol.

[0241] The reaction results are shown in Table 15.

[0242] Table 15. Pt SA Results of Co / CeO2 catalytic conversion of 2,5-dimethyltetrahydrofuran

[0243]

[0244] Example 25

[0245] 5-Methylfurfural bond breaking and ring-opening reaction

[0246] a) Take 0.1 g of Pt obtained according to Example 7 SA Co / CeO2 catalyst and 10 mL of isopropanol solution containing 0.11 g 5-methylfurfural and 0.213 g n-dodecane were added to a high-temperature and high-pressure reactor.

[0247] b) Replace the air in the reactor with hydrogen three times, then fill the reactor with hydrogen until the initial pressure is 3 MPa, raise the temperature to 140℃, stir at 500 r / min, and react for 5 h.

[0248] c) After the reaction is complete, stop stirring and cool to room temperature. Then, release the pressure and open the vessel to separate the liquid product and catalyst. Use mass spectrometry-gas chromatography to perform qualitative and quantitative analysis on the liquid product and calculate the substrate conversion rate and the yield of C6 linear polyol.

[0249] The reaction results are shown in Table 16.

[0250] Table 16. Pt SA Results of Co / CeO2-catalyzed conversion of 5-methylfurfural

[0251]

[0252] Example 26

[0253] 5-Methylfurfural bond cleavage and ring-opening reaction

[0254] a) Take 0.1 g of Ru obtained according to Example 7 SA Co / CeO2 catalyst and 10 mL of isopropanol solution containing 0.112 g 5-methylfurfural and 0.213 g n-dodecane were added to a high-temperature and high-pressure reactor.

[0255] b) Replace the air in the reactor with hydrogen three times, then fill the reactor with hydrogen until the initial pressure is 3 MPa, raise the temperature to 150℃, stir at 500 r / min, and react for 3 h.

[0256] c) After the reaction is complete, stop stirring and cool to room temperature. Then, release the pressure and open the vessel to separate the liquid product and catalyst. Use mass spectrometry-gas chromatography to perform qualitative and quantitative analysis on the liquid product and calculate the substrate conversion rate and 2,5-hexanediol yield.

[0257] The reaction results are shown in Table 17.

[0258] Table 17. Ru SA Results of Co / CeO2-catalyzed conversion of 5-methylfurfural

[0259]

[0260] Example 27

[0261] Cyclic stability test of pentoxymethylfurfural selective ring-opening reaction catalyst

[0262] The catalyst after reaction 17 was filtered and separated, washed multiple times with ethanol, and dried under vacuum to obtain the catalyst after one cycle. This catalyst was used for the selective ring-opening reaction of pentahydroxymethylfurfural under the same operating conditions as in Example 17. The operation was repeated 10 times, and the activity data of the catalyst after 10 cycles were measured. The reaction results are shown in Table 18.

[0263] Table 18. Pt SA Stability test results of Co / CeO2 catalysis for pentahydroxymethylfurfural

[0264]

[0265] The results in Table 13 show that the catalyst maintained stable catalytic activity after multiple cycles, and the substrate conversion and product yield remained at a high level, indicating that the catalyst has good cycle stability. Figure 2 Pt as described in Example 1 SA X-ray photoelectron spectroscopy (XPS) analysis results of Pt 4f in fresh samples and samples after 10 cycles of reaction of Co / CeO2 catalyst. After 10 cycles of reaction, the chemical environment of Pt species in the catalyst did not change significantly, and the positions and peak area ratios of Pt-related characteristic peaks remained basically stable, with no obvious Pt-related peaks appearing. 0 The increase in species or the change in Pt oxidation state indicate that Pt single atoms can remain stable during the reaction. These results demonstrate that a strong interaction exists between Pt single atoms and the Co / CeO2 interface, effectively inhibiting the migration, aggregation, and deactivation of Pt species during the reaction. This further proves that the constructed Pt–Co–CeO2 interface structure has good structural stability and recyclability.

[0266] The above embodiments verified the feasibility of the technical solution of the present invention from the aspects of catalyst preparation, structural characterization, catalytic performance, stability, and mechanism analysis. The results show that the noble metal single-atom-Co / CeO2 interfacial catalyst constructed in this invention has a well-defined interfacial structure, excellent catalytic activity, and good cycle stability. It can efficiently catalyze the hydrogenation ring-opening reaction of various biomass furan platform compounds to prepare corresponding C5 / C6 straight-chain alcohol products. Different noble metal types and doping amounts can effectively control the catalyst performance, demonstrating that the catalytic system of this invention has good universality, controllability, and industrial application potential.

[0267] In summary, this invention focuses on the construction of a single-atom-doped Co / CeO2 interfacial catalyst and its application in the selective hydrogenation and ring-opening of biomass-derived furan platform compounds to prepare straight-chain C5 / C6 alcohols. In terms of application performance, this catalytic system exhibits excellent catalytic performance and broad substrate applicability. From a reaction performance perspective, the catalyst of this invention can achieve efficient and targeted conversion of various biomass-derived furan platform compounds, including furfural, furfuryl alcohol, tetrahydrofurfuryl alcohol, 5-hydroxymethylfurfural, 2,5-dihydroxymethylfuran, 5-methylfurfural, 5-methylfurfuryl alcohol, and other furan ring derivatives, under relatively mild reaction conditions (reaction temperature 140–180 °C, hydrogen pressure 3 MPa), and with high selectivity, to generate C5 / C6 straight-chain polyols such as 1,5-pentanediol, 1,2-pentanediol, 1,2-hexanediol, 2,5-hexanediol, and 1,2,6-hexanetriol. Compared with existing Pt-based, Co-based and traditional bimetallic catalytic systems, the catalyst of this invention can achieve higher substrate conversion and target product selectivity under milder conditions, while effectively suppressing side reactions such as excessive hydrogenation, cracking and condensation, and has superior catalytic performance.

[0268] Regarding catalyst stability, the catalyst of this invention can still maintain high catalytic activity and target product selectivity after multiple cycles of use, and the active components do not show obvious aggregation or loss. This indicates that a stable interaction has been formed between the Pt single atom and the Co / CeO2 interface, which effectively improves the structural stability and deactivation resistance of the catalyst, laying the foundation for the long-term stable operation and industrial application of the catalyst.

[0269] Furthermore, by introducing a single metal atom, this invention achieves synergistic regulation of the electronic structure of the Co active center and the oxygen vacancies at the CeO2 interface, constructing an M–Co–O structure with well-defined structural characteristics. v Interfacial synergistic active center. This interfacial catalytic center combines multiple functions, including efficient hydrogen activation, rapid active hydrogen migration, substrate selective adsorption, and furan ring C–O bond activation. It can achieve efficient coupling of multiple key reaction steps, such as hydrogen activation, active hydrogen overflow, selective ring opening of furan ring, and subsequent hydrogenation, thereby realizing one-step efficient and directional conversion of biomass-derived furan platform compounds into straight-chain C5 / C6 alcohols in a single reaction system.

[0270] Overall, this invention provides a single-atom-doped Co / CeO2 interfacial catalyst system that is simple to prepare, structurally stable, exhibits excellent catalytic performance, and has broad substrate applicability. It establishes an interfacial catalytic strategy based on the regulation of Co active centers and interfacial oxygen vacancies by doped metal single atoms. This provides a technical route for the high-value conversion of biomass-derived furan platform compounds into straight-chain C5 / C6 alcohols, characterized by mild reaction conditions, simplified process flow, high atom economy, and promising industrial application prospects. Furthermore, this catalyst design strategy can provide new design ideas and theoretical basis for the selective catalytic conversion of other biomass platform molecules and the development of interfacial catalysts.

[0271] The technical solutions disclosed and proposed in this invention can be implemented by those skilled in the art by appropriately modifying the conditions and routes, etc. Although the methods and preparation techniques of this invention have been described through preferred embodiments, those skilled in the art can obviously modify or recombine the methods and technical routes described herein without departing from the content, spirit, and scope of this invention to achieve the final preparation technique. It should be particularly noted that all similar substitutions and modifications are obvious to those skilled in the art and are considered to be included within the spirit, scope, and content of this invention.

Claims

1. A single-atom-doped Co / CeO2 interfacial catalyst, characterized in that, With M SA Co / CeO2 means that the loading of Co is 10 to 30% of the total mass of the catalyst; M is the doped single atom, including Pt, Ru, Pd, and Rh, with a doping amount of 0.2 to 1.0 wt%.

2. The single-atom doped Co / CeO2 interface catalyst as claimed in claim 1, characterized in that M in the catalyst is dispersed in the Co / CeO2 interface in the form of oxygen-coordinated single atoms, and Co is loaded on the CeO2 surface in the form of nanoclusters, forming an atomic-level noble metal single atom-metal nanocluster-oxide support interface structure.

3. The method for preparing the single-atom doped Co / CeO2 interfacial catalyst of claim 1, characterized in that, Includes the following steps: 1) Add cerium nitrate hexahydrate, cobalt nitrate hexahydrate, and polyvinylpyrrolidone in a mass ratio of 1.6-2.4:1:0.4-1.2 to ethylene glycol solvent and stir at room temperature to form a homogeneous mixed solution; 2) At room temperature, stir continuously at a speed of 400-500 rpm, while adding deionized water to the above mixed solution, and continue stirring for 0.5-2 h to obtain a uniform and transparent solution; 3) Transfer the transparent solution to a stainless steel hydrothermal reactor and heat it in a rotary oven at 140-160 ℃ for 20-24 h to obtain a solid product; 4) The obtained solid product was washed by centrifugation with ethanol 5 to 7 times to remove unreacted substances and organic residues, and then dried at 60 to 100 °C for 10 to 20 h to obtain the Co / CeO2 precursor; 5) The noble metal precursor solution is added to the Co / CeO2 precursor by an equal-volume impregnation method; wherein the noble metal precursor is selected from one of sodium hexachloroplatinate, ruthenium trichloride, palladium chloride or rhodium trichloride. 6) The impregnated precursor was dried and then calcined in air in a muffle furnace to obtain M. SA Co / CeO2 precursor; 7) Take the obtained M SA The Co / CeO2 precursor was reduced in a 5% (v / v) H2 / N2 mixed atmosphere at 350–400 °C to obtain a single-atom-doped Co / CeO2 interfacial catalyst, denoted as M. SA Co / CeO2.

4. The preparation method according to claim 3, characterized in that, Step 1) The purity of the ethylene glycol is not less than 99.8%, and the total concentration of metal salt in the mixed solution is 0.02-0.10 mol / L; Step 1) After adding deionized water, the stirring conditions are 400-500 rpm for 0.5-1.5 h.

5. The preparation method according to claim 3, characterized in that, Step 2) The volume ratio of deionized water to ethylene glycol is 1:5 to 1:

8.

6. The preparation method according to claim 3, characterized in that, In step 6), the calcination temperature is 450-550 ℃ and the calcination time is 2-3 h.

7. The preparation method according to claim 3, characterized in that, In step 7), the reducing atmosphere is a 5% hydrogen / nitrogen mixture, and the reduction time is 3-5 hours.

8. The application of the single-atom doped Co / CeO2 interfacial catalyst of claim 1 in the preparation of C5 / C6 linear polyols.

9. The application as described in claim 8, characterized in that, The single-atom-doped Co / CeO2 interfacial catalyst, furan platform compound substrate, and reaction solvent were added to a high-pressure reactor and thoroughly mixed. The reactor was heated to 120-180 °C and stirred for 1-8 h. After sealing the reactor, the air inside was replaced with hydrogen and the pressure was increased to 2-4 MPa. After the reaction was completed, stirring was stopped, the reactor was cooled to room temperature, and then the pressure was released and the reactor was opened to separate the liquid product and the catalyst.

10. The application as described in claim 8, characterized in that, The catalyst-to-substrate mass ratio is 1:0.82-1.32; the substrate concentration is 0.05-2 mol / L; the biomass-derived furan platform compound includes one or more of the following furan derivatives: furfural, furfuryl alcohol, tetrahydrofurfuryl alcohol, 2-methylfuran, 2-methyltetrahydrofuran, 5-hydroxymethylfurfural, 2,5-dihydroxymethylfuran, 2,5-dihydroxymethyltetrahydrofuran, 2,5-dimethylfuran, 2,5-dimethyltetrahydrofuran, 5-methylfurfural, 5-methylfurfuryl alcohol; the linear polyol includes 1,2-pentanediol, 1,5-pentanediol, 1,2-hexanediol, 1,5-hexanediol, 2,5-hexanediol, 1,2,6-hexanetriol, and mixtures thereof.

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