The synergistic enhancement of catalytic activity and selectivity constitutes a critical challenge in modern heterogeneous catalysis， which directly influences target product yield， reaction energy efficiency， and process economics. Molecular imprinting technology （MIT） has demonstrated exceptional potential in overcoming this limitation by enabling the rational design of molecularly imprinted catalysts （MICs） with high activity， superior selectivity， and favorable thermal stability. These advanced catalysts combine biomimetic recognition with heterogeneous catalysis， wherein precisely engineered imprinted cavities integrate two key structural features， including catalytically active sites with tailored electronic properties and molecular imprinting cavities with specific structure. These imprinted cavities endow MIC exhibit exceptional molecular recognition capabilities， enabling selective binding to substrates， intermediates， and products via reversible covalent bonds， electrostatic interactions， hydrogen bonding， and other noncovalent forces. This precise recognition facilitates the mediation of specific reaction pathways， ensuring high-selectivity synthesis of target compounds. The preparation of MIC typically involves three sequential steps： template molecule assembly， template configuration fixation， and template molecule elution. In the template assembly stage， reversible interactions are commonly employed to drive the self-assembly of template molecules （target-structured molecules） with functional monomers， forming stable imprinted complexes. For template configuration fixation， cross-linking polymerization or surface engineering techniques are predominantly utilized to immobilize the assembled structure， ensuring the preservation of cavity geometry after template removal. Subsequent elution of the template molecules generates imprinted cavities on the MIC surface. By optimizing template assembly methodologies and fixation strategies based on application-specific requirements， both the cavity structure and catalytic binding modes can be precisely modulated， thereby enhancing catalytic activity and selectivity for tailored catalyst design. Additionally， the introduction of precious metals （e.g.， Rh， Ru， Au， Ag） and non-precious metals （e.g.， Fe） as catalytic active sites further augments MIC performance. Despite the promising application potential of MICs in chemical synthesis， their preparation and characterization remain challenged by several key limitations， like the sub-nanostructured imprinted cavities hindering detailed structural elucidation of binding sites， template molecules encapsulation within the polymer matrix during cross-linking resulting in incomplete elution， quantitative analysis of metal species in polymer-based MICs lacking standardized methodologies. To address these challenges and guide design of high-performance MICs， researchers have integrated advanced characterization techniques to comprehensively evaluate MIC structure， including morphology， elemental composition， active site distribution， chemical bonding information， and metal coordination environments. Currently， MICs exhibit tremendous application potential in the synthesis of various fine chemical products， but related review articles focusing on MIC are relatively scarce. This review focuses on the applications of MIT in thermal catalysis， systematically discussing its fundamental principles， theoretical foundations， and historical development. Next， various typical synthetic strategies for MICs， including bulk， suspension， precipitation， and surface imprinting polymerization are summarized. Then series of key characterization methods， such as Fourier transform infrared spectroscopy （FT-IR）， elemental analysis （EA）， and high-resolution mass spectrometry （HRMS） are described to analyze the structure of MICs. Moreover， different types of MICs （noble metal， non-noble metal， and metal free MICs） are used in catalytic reactions， including hydrolysis， oxidation， reduction， coupling， and polymerization. In addition， the photo-/electrocatalysis， artificial enzyme design， sensing， and adsorption/separation are also discussed as emerging applications of MIT. Finally， the research challenges and future directions are proposed in this field.

The dehydrogenation of methylcyclohexane (MCH) is a widely used hydrogen storage technology, but nowadays, precious metal catalysts such Pt are used for this reaction and non-precious metal catalysts suffer from low selectivity and instability problems. Two catalysts, Ni20/TiO2 and Ni20/Al2O3, were prepared through the improved co-precipitation method and their dehydrogenation performance of MCH was compared. It was found that the application of TiO2 carrier could significantly reduce the acidity of the catalysts, and the nickel particles could be stably dispersed on the carriers, which could effectively improve the selectivity of the target product (toluene). In addition, the influences of different Ni contents, reaction temperatures, and weight hourly space velocity (WHSV) on the performance of the catalysts were also evaluated, and the results showed that the catalyst with 17.16 % Ni content exhibited high activity with up to 86.48 % conversion of MCH and 96.51 % selectivity of toluene, under atmospheric pressure condition with the reaction temperature of 375 °C and WHSV of 1.9 h−1, while 96.03 % and only 42.64 %, respectively, for the Ni20/Al2O3 catalyst. In addition, the catalyst exhibited excellent anti-coking ability, indicating that it has a promising future for industrial applications.

Hydroxylation of inert benzene through the activation of the Csp2-H bond is a representative reaction about the transformation of C-H bonds to C-O bonds, which has far-reaching guiding significance but remains a challenging scientific problem. To overcome this problem, a series of VOx-Ga2O3/SiO2-Al2O3 were prepared to achieve an efficient and economical hydroxylation path of benzene to phenol. The results showed that the phenol yield was 72.89% (selectivity >98.1%) under the optimum conditions. The reason is that the C-H bond in the benzene ring is activated by heterolysis over VOx-Ga2O3/SiO2-Al2O3 catalyst. Meanwhile, the introduction of aluminum (Al) and gallium (Ga) made a qualitative change in the catalyst, enhancing the electron motion and spin motion of vanadium species, resulting in the increase of V4+/V5+ ratio. In addition, the catalyst can provide an optimal acidic environment and a 3D cross-linked surface structure that facilitates product diffusion.

Growing demand of short chain olefins such as propylene for plastic production drives the development of high performing catalysts for propane dehydrogenation (PDH). Here, a confinement strategy originating from metalsulfur clusters was employed to fabricate defective MoPtSx phase via anchoring by coordinatively unsaturated Al sites present on alumina, followed by reduction under H2 flow at high temperature. This catalyst with a low Pt content exhibits great ability for C-H activation with high intrinsic activity and facile propylene desorption in PDH reaction. More importantly, this catalyst shows excellent stability during long-term tests with both stable conversion and selectivity. Through combined X-ray absorption spectroscopy, electron microscopy and electron paramagnetic resonance measurements it could be affirmed that the isolated and electron-enriched Pt sites as well as their proximity to adjacent sulfur vacancies is vital for the first and second C-H bond activation, and suppressing of C-C cleavage which otherwise lead to coking.

N-Methyl-pyrrolidone (NMP) is an important coating solvent for the production of lithium batteries, and its water content will greatly affect the coating quality and energy density of lithium batteries, which needs to be reduced to 200 ppm. The current vacuum distillation technology suffers from high operating costs and high energy consumption, whereas the pervaporation technology only achieves solvent dehydration up to 99.5%. Therefore, it is of great significance to carry out the study of trace water removal from NMP solvents. In this paper, the A-type molecular sieve adsorption method was used to remove trace water from the NMP solvent, and the effects of molecular sieve type, particle size, adsorption temperature, feeding amount, and contact time on the dehydration performance of NMP system were first investigated. Adsorbed at 25 degrees C for 240 min at a feeding amount of 120 g/L, 3A molecular sieves were able to reduce the water content of the NMP solvent from 5000 to 140 ppm. Second, Langmuir and Freundlich equations were used to fit the static isothermal adsorption data, and the results showed a better correlation of the Langmuir equation. Then, the adsorption kinetics and diffusion mechanism were analyzed by the kinetic model and the Crank single-pore diffusion model. The R-2 of the pseudo-first-order kinetic model was 0.9993, which was more suitable for describing the process of adsorption of water from the NMP solvent by 3A molecular sieves, and the effective diffusion coefficient D-e = 2.986 x 10(-8) cm(2)/s was calculated for the Crank single-pore adsorption model, which proved water molecules on the 3A molecular sieve. The diffusion of water molecules on the inner surface of the pores is the controlling step of the adsorption process. Finally, the fixed-bed dynamic penetration curves were investigated to obtain the experimental data of fixed-bed adsorption, and the experimental data were fitted using the Thomas and Yoon-Nelson models, which showed that both models could describe the adsorption behavior of trace water in NMP solvents on 3A molecular sieves. This study provides a new idea for the removal of trace water in NMP systems, and a series of model fitting parameters provide basic data for industrial scale-up.

The highly selective hydrogenation to remove olefins is a significant refining approach for the reformate. Herein, a library of transition metal for reformate hydrogenation is tested experimentally to validate the predictive level of catalytic activity from our theoretical framework, which combines ab initio calculations and microkinetic modeling, with consideration of surface H-coverage effect on hydrogenation kinetics. The favorable H coverage of specific alloy surface under relevant hydrogenation condition, is found to be determined by its corresponding alloy composition. Besides, olefin hydrogenation rate is determined as a function of two descriptors, i.e. H coverage and binding energies of atomic hydrogen, paving the way to computationally screen on metal component in the periodic table. Evaluation of 172 bimetallic alloys based on the activity volcano map, as well as benzene hydrogenation rate, identifies prospective superior candidates and experimentally confirms that Zn3Ir1 outperforms pure Pd catalysts for the selective hydrogenation refining of reformate. The insights into H-coverage-related microkinetic modelling have enabled us to both theoretically understand experimental findings and identify novel catalysts, thus, bridging the gap between first-principle simulations and industrial applications. This work provides useful guidance for experimental catalyst design, which can be easily extended to other hydrogenation reaction.

Transition metal oxides (TMOs) are highly dense in energy and considered as promising anode materials for a new generation of alkaline ion batteries. However, their electrode structure is disrupted due to significant volume changes during charging and discharging, resulting in the short cycle life of batteries. In this paper, the hierarchical Ni3V2O8@N-doped carbon (Ni3V2O8@NC) hollow double-shell microspheres were prepared and used as electrode materials for lithium-ion batteries (LIBs). The utilization efficiency and ion transfer rate of Ni3V2O8 were improved by the hollow microsphere structure formed through nanoparticle self-assembly. Furthermore, the uniform N-doped carbon layer not only enhanced the structural stability of Ni3V2O8, but also improved the overall electrical conductivity of the composite. The Ni3V2O8@NC electrode has an initial discharge capacity of up to 1167.3 mAh g-1 at a current density of 0.3 A g-1, a reversible capacity of up to 726.5 mAh g-1 after 200 cycles, and still has a capacity of 567.6 mAh g-1 after 500 cycles at a current density of 1 A g-1, indicating that the material has good cycle stability and high-rate capability. This work presents new findings on the design and fabrication of complex porous double-shell nanostructures.

The selective hydrogenation of alkynes to alkenes is widely applied in the chemical industry; nevertheless, achieving highly selective hydrogenation with high catalytic activity is considerably challenging. Herein, ultrafine PdCu bimetallic nanoparticles encapsulated by high-surface-area mesoporous α-Al2O3 were prepared by high-temperature calcination-reduction using a porous organic framework (POF) as the template. As-obtained PdCu@α-Al2O3 exhibited a high selectivity of 95% for the semi-hydrogenation of phenylacetylene as a probe reaction under mild reaction conditions. The separation of continuous Pd atoms and modification of the Pd electronic state by Cu atoms suppressed β-hydride formation and alkene adsorption, contributing to high selectivity for the catalytic hydrogenation of alkynes. The catalytic activity was maintained after 7 cycles due to the strong interaction between the PdCu bimetallic nanoparticles and α-Al2O3 as well as the encapsulation effect of mesoporous α-Al2O3. Thus, the current work provides a facile strategy for fabricating high-surface-area mesoporous α-Al2O3-supported catalysts for industrial catalysis applications.

Alloying is an effective approach to improve the catalysis performance of Pd-based catalysts for the selective hydrogenation of diolefins towards monoolefines. Herein, PdAgCu ternary nanoalloy catalysts were synthesised by a stepwise impregnation method for isoprene selective hydrogenation. The addition of a moderate amount of Ag and Cu to Pd significantly enhances the isoamylene selectivity in the isoprene hydrogenation, and decreases the non-desired over-hydrogenation. In addition, the loading molar ratio of PdAgCu with 3 : 2 : 3 as the optimal ternary nanoalloy composition maximizes the isoprene conversion (98%) and the monoolefins yield (92%). The surface structure of the catalyst was probed using H2-TPR, TEM, XRD, and XPS characterization methods, and it was confirmed that the surface Pd composition ratio between the metallic and oxidized states shows significant effects on the monoolefines yield. This work demonstrates the advantages of PdAgCu ternary nanoalloy catalysts for isoprene selective hydrogenation, which also provides guidelines for the development of other Pd-based ternary nanoalloys for diolefins selective hydrogenation.

分析了某 120 万t/a重整抽余油加氢装置紧急停车原因,利用H2-程序升温还原、X射线衍射、N2物理吸附等分析方法,表征了卸出催化剂的性质,并采取了相应对策.结果表明:由于加氢原料中不饱和烃含量严重超标,引起反应放热量剧增,高温条件下又引发了不饱和烃的聚合、生焦,释放热量叠加,发生了床层飞温,以及结焦使床层堵塞、压差快速上升;在卸出催化剂前的通空气钝化过程中,催化剂床层底部因堵塞引起空气偏流,局部富氧条件下还原态镍过度氧化以及焦炭燃烧的大量放热,使催化剂经历了 700℃以上的高温氧化,导致催化剂结块、变色;部分卸出催化剂物化性质与新鲜催化剂较为接近,可以回填继续使用,回填量约占新鲜催化剂首次装填质量的 70%.

Selective hydrogenation of alkynes to obtain alkenes is a key reaction in petrochemical and fine chemical industries. However, the development of stable and highly selective catalysts with uniformly dispersed active sites is still immensely challenging for the semi-hydrogenation of alkynes. In this study, N-doped porous carbon nanospheres (NPCNs) were synthesized by the nanoemulsion self-assembly and subsequently carbonization method. Ultrafine PdCu bimetallic nanoparticles (NPs) were uniformly dispersed and immobilized on NPCNs. The obtained PdCu/NPCNs catalyst exhibited an open framework and abundant active sites originating from ultrafine PdCu NPs. In the semi-hydrogenation of alkynes, the PdCu/NPCNs catalyst exhibited a remarkable performance and stability, outperforming most of the classical catalysts. The excellent performance was related to the introduction of a secondary metal Cu, which can regulate the electronic state of Pd active sites to further enhance the hydrogenation activity and selectivity. Hence, the facile approach reported herein may be useful for constructing highly dispersed bimetallic NP-based catalysts for selective hydrogenation of alkynes in the petrochemical industry.

通过简便、经济的方法合成了 MWCNTs/ZIF-67复合材料,并运用SEM、TEM、XRD、XPS等技术手段对该复合材料进行了表征.为了评估MWCNTs/ZIF-67催化剂的催化活性,在NaBH4存在下进行了对硝基苯酚(4-NP)的还原实验.结果表明,MWCNTs/ZIF-67催化剂具有很好的催化性能,在6min内对4-NP的催化效率高达99.82％,表观速率系数达到0.4973min-1.此外,该材料可以通过磁铁从水溶液中收集,便于回收和再利用.且经过5次循环后,复合材料的催化活性仍很高,表明该复合材料有较好的稳定性,可以作为去除环境污染物的新型催化材料.

The composition effect of PdPt alloys on preferential hydrogenation of C6 olefins over benzene is studied by combining density functional theory calculations and microkinetic modeling. A trade-off between activity and selectivity is found with increasing Pt component. Pd3Pt1 is identified with high selectivity (low aromatic depletion), while Pd1Pt1 and Pd1Pt3 are more active for olefin hydrogenation. The PdPt alloys present superior sulfur tolerance compared to Pd.

The catalytic partial hydrogenation of alkynols is a key approach for the synthesis of enols, which are crucial chemical intermediates for pharmaceuticals and essences. Low selectivity is the main challenge of the partial hydrogenation of alkynols due to the easy over-hydrogenation of alkynyl groups. Herein, ultrafine PdZn bimetallic nanoparticles (NPs) were anchored on a S-doped mesoporous carbon catalyst (PdZn/Meso_S-C) and used for the partial hydrogenation of alkynols. Zn metal with a high electron density was used to modify the active metal Pd to change the electronic and geometric configuration of the Pd active sites, which improve the selectivity of enols during the partial hydrogenation of alkynols. Furthermore, the use of a S-doped mesoporous carbon support dispersed and stabilized the ultrafine PdZn NPs due to strong interactions between the metal atoms and S sites. This also prevented PdZn ultrafine NPs from aggregating and increased the partial hydrogenation selectivity. The partial hydrogenation of propynol ethoxylate (PME) catalyzed by PdZn/Meso_S-C reached 96.0% enol selectivity, while the alkynol conversion reached 97.5%. The general applicability of PdZn/Meso_S-C for the partial hydrogenation of various alkynols has also been demonstrated. Thus, this work has great application prospects for the high-efficiency catalytic partial hydrogenation of alkynols.

Semi-hydrogenation of alkynes to prepare alkenes is an important reaction in the petrochemical and fine chemical industries. The use of conventional Pd nanoparticle-based catalysts is limited by alkyne over-hydrogenation and low Pd utilization. In this study, a nitrogen-doped mesoporous carbon material (m-NC), which was rich in defect sites after Zn volatilization, was fabricated by the carbonization of ZIF-8. Ultrafine PdCo bimetallic nanoclusters with Co atom-modified Pd active site electronic and compositional structure were highly dispersed and confined in m-NC. As-obtained Pd0.43Co1/m-NC was used for the semi-hydrogenation of alkynes and it exhibited high selectivity with high conversion under mild reaction conditions. Pd0.43Co1/m-NC also exhibited excellent stability in leaching tests and maintained its catalytic activity for at least nine reaction cycles. The highly dispersed active sites in Pd0.43Co1/m-NC served as the active sites for the catalytic semi-hydrogenation of alkynes; as a regulator, the second metal Co effectively improved selectivity, and m-NC endowed the catalyst with excellent stability. The research work presented here may provide a foundation for the design of highly active, selective, and stable Pd-based bimetallic catalysts for selective hydrogenation.

概述了裂解汽油一段选择加氢钯系和镍系催化剂在我国的工业化应用情况,并从载体材料、制备工艺优化以及添加助剂改性3个方面,综述了此系列钯系和镍系催化剂在国内外的研究进展,预测了今后需持续注重及改进的相关方面;最后展望指出,针对特定原料性质开发与之相匹配的选择加氢工艺及其配套专用催化剂,将是未来裂解汽油一段选择加氢催化剂研发的主方向.

以镍盐和铝盐为原料,采用共沉淀法制备出镍系重整抽余油加氢精制催化剂(牌号为LY-2005 B),并在中国石油大庆石化120万t/a连续重整装置配套的抽余油加氢装置中进行了工业化应用.结果表明:以溴价为(15～20)×10-2 g/g的混合碳六为原料,在反应压力为0.3 MPa,反应器入口温度为115～120℃,床层温升为40～50℃,氢气流量为200 m3/h,进料流量为1.0～2.0 t/h,加氢原料含苯量波动较大且经常超标的生产条件下,正己烷产品中含苯量为0μg/g,溴价不高于0.01×10-2 g/g,赛波特颜色号为30,能够满足技术协议要求.

The composition-dependent adsorption and catalytic properties of PdAg bimetallic surfaces for the partial hydrogenation of 1,3-butadiene to 1-butene were studied by density functional theory. With the increase of Ag content, the activity and selectivity for the partial hydrogenation of 1,3-butadiene to 1-butene were enhanced with the decrease in binding strength of adsorbates. The increase of surface Ag content in PdAg catalysts can thus enhance the catalytic performance of the hydrogenation of 1,3-butadiene.

对碳四(C4)馏分中的炔烃进行选择性催化加氢是实现混合C4资源高附加值利用的有效途径,具有显著的经济效益和社会效益.通过介绍C4炔烃的利用现状,并从选择性加氢机理入手,对国内外现有C4炔烃催化剂的研究与应用进行了概述;对非贵金属镍(Ni)、铜(Cu)催化剂与贵金属钯(Pd)催化剂的优缺点进行了对比,指出了Pd系列催化剂是目前最适合作为C4炔烃选择加氢的催化剂.针对Pd系催化剂目前存在的不足,提出了一些改进策略与今后的研究方向.分析研究表明,Pd系纳米催化剂的载体预处理、助剂改性、微观调控以及单原子催化剂的可控制备是国内C4资源充分利用的重要途径.

Pyrolysis gasoline is applied to extract aromatics and to be gasoline blending stock, and its stabilization by catalytic hydrogenation under mild temperature is an important reaction in petrochemical field. Thereinto, styrene hydrogenation was considered as an example for the assessment of the catalysis performance for pyrolysis gasoline hydrogenation. In this work, the adsorption and diffusion of reactants (styrene and H) and the activation energy of styrene hydrogenation on Pd(111), Pd(100), and Pd(110) surfaces are discussed by density functional theory calculations. The adsorption energy of reactants (styrene and H) decreases in the order of Pd(110) > Pd(111) > Pd(100). The activation barriers with feasible intermediate products are investigated and the reaction activity based on the activation barriers follows the order of Pd(111) > Pd(100) > Pd(110). In addition, the diffusion barrier for styrene or H is smaller than the reaction barrier of styrene hydrogenation, indicating the true rate limiting step is the process of hydrogenation rather than the diffusion. Our results provide theoretical guide for the prepared catalyst with feasible surfaces by careful selection of preparation techniques in experiments.