Co-based catalysts have shown promising application prospects in propane dehydrogenation (PDH) due to their excellent C-H bond activation ability and environmental friendliness. However, issues such as unclear active sites and insufficient stability during the reaction process limit the application. In this work, a Co2+ embedding strategy was proposed to suppress carbon deposition, thereby achieving high propylene selectivity and long-term stability. Utilizing the "memory effect" of ammonium aluminum carbonate hydroxide (AACH), cobalt species are embedded into the lattice during the crystal reconstruction of AACH, successfully achieving a Co2+-embedded Co/Al-0.1 catalyst. By systematically adjusting the Co/Al molar ratio (0.05-0.6), rational regulation of Co2+ content is achieved. The Co/Al-0.1 with stably embedded Co2+ maintains propylene selectivity of above 90%, with a coking rate of 1.32 h-1, one third that of Co/Al2O3-IMP prepared by impregnation. Correspondingly, Co/ Al-0.1 exhibits a high long-term stability with a deactivation rate constant kd of 0.0075 h-1, less than one fifth that of Co/Al2O3-IMP (kd = 0.0406 h-1). In situ propylene adsorption-desorption infrared spectroscopy and theoretical calculations indicate that propylene easily desorbed from the stable embedded Co2+, thereby inhibiting deep dehydrogenation of propylene and C-C bond cleavage, which enhances propylene selectivity and anti-coking performance.

The balance between catalytic activity and product selectivity remains a challenge in partial oxidation reactions, because its products are prone to be further oxidized. In this paper, a small amount of Ni was introduced on the surface of the supported AuPd alloy nanoparticles (NPs) as a promoter to construct the Ni/AuPd interface for benzyl alcohol partial oxidation, which helped to improve the selectivity of benzaldehyde. The results showed that the introduction of a small amount of Ni (<0.5 wt%) led to no obvious change of the catalytic activity, but the selectivity of benzaldehyde was greatly improved. When Ni content exceeds 1.0 wt%, the benzyl alcohol conversion decreased significantly. This is mainly because a large amount of Ni led to an obvious aggregation of Pd on the catalyst and a large amount of surface Ni species partially covered the active components, resulting in a low catalytic activity. Introducing a small amount of Ni improved the benzaldehyde selectivity and Ni species presented as NiO and NiOOH on catalyst xNi/AuPd/MCF-H. Theoretical calculation results show that the improved benzaldehyde selectivity was attributed to the easy desorption of benzaldehyde from NiO and NiOOH surfaces.

Addressing the global challenge of waste plastic management, catalytic cracking by utilizing zeolite catalysts offers a sustainable approach for converting plastics into valuable products. The acidity and diffusion of zeolites play a critical role in determining the efficiency of this process. However, conventional aluminium-containing zeolites exhibit excessive acidity, promoting excessive cracking and secondary bimolecular reactions, leading to coke formation. Additionally, microporous zeolites with limited diffusion of large molecules significantly impair their activity and overall utilization efficiency. In this study, we developed gallium-modified MFI zeolite catalysts (Ga-MFI) that possess a well-balanced micro- and mesoporosity along with controlled acidity. These Ga-MFI catalysts exhibited enhanced diffusion properties and moderate acidity, which contributed to an improved gasoline yield (64.84-77.69%), alongside a significant reduction in liquefied gas yield (from 23.21% to 13.07%) during the catalytic cracking of low-density polyethylene (LDPE) when compared to the ZSM-5 catalyst. Furthermore, the Ga-MFI catalysts demonstrated a significant enhancement in the selectivity for cycloalkenes within the liquid products, increasing from 35.62% to 51.53%. This improvement can be attributed to the promotion of bimolecular cracking reactions occurring on moderate acidic sites, which facilitate olefin formation, as well as the high concentration of Lewis acid sites that aid in the dehydrogenation of cycloalkanes to cyclo-olefins. These findings underscore the potential of Ga-MFI zeolite as a promising catalyst for the sustainable conversion of plastic wastes.

In the utilisation of most oxide-based propane dehydrogenation (PDH) catalysts, each reaction-regeneration cycle necessitates both coke combustion and hydrogen reduction to achieve complete regeneration of the catalyst. However, the need for hydrogen reduction makes it difficult to use such catalysts in chemical looping oxidative dehydrogenation (CL-ODH) processes. This study prepared a series of CrZrOx catalysts with Cr/Zr atomic ratios ranging from 0.02 to 1 using a co-precipitation method. Electron paramagnetic resonance (EPR) analysis revealed that the catalyst surface in its oxidised state is rich in oxygen vacancies. These vacancies created numerous coordinated unsaturated Zr (Zrcus)-based active sites directly linked to the catalyst's unique catalytic activity. This catalyst was paired with a Cu2MnOx@Na2WO4 oxygen carrier to perform the CL-ODH of propane. The results demonstrated that the catalyst-oxygen carrier coupling system significantly enhanced single-pass propane conversion in the PDH process, increasing the initial propane conversion from 27.2% to 35.9%. The enhanced conversion, along with the observed hydrogen consumption over time, confirmed that the PDH process was coupled with hydrogen oxidation via the lattice oxygen of the oxygen carrier. This coupling broke through the thermodynamic equilibrium, thereby significantly improving the single-pass propane conversion. These findings provide valuable insights for designing novel catalyst systems tailored for the CL-ODH of propane.

Porous alumina with high specific surface area (SSA) and large pore volume (PV) is highly desired in various applications; however, its synthesis without an organic template faces a great challenge. Herein, we propose a novel template-free strategy based on intercalation-exfoliation with silica to weaken boehmite (alumina precursor) interlayer forces and achieve the exfoliation of boehmite into two-dimensional (2D) nanosheets, which can easily be scaled up. The as-prepared 2D nanosheets with 2-nm thickness could be assembled to form boehmite with 542 m 2 g −1 SSA and 2.43 cm 3 g −1 PV. The porous alumina obtained from the thermal/hydrothermal treatment of the 2D nanosheets at different temperatures possesses a hierarchical porous structure superior to most of the reported alumina synthesized with organic templates, exhibiting excellent performance in the adsorption of large organic molecules. This research provides a new strategy for synthesizing 2D boehmite nanosheets and porous alumina materials, demonstrating great potential in catalysis and adsorption.

Due to the excellent diffusion performance, carbon materials with interconnected large pores are widely used, however, the synthesis of mesoporous carbonis always cumbersome and costly. In this work, the pyrolysis behavior of rice husk (RH) was studied and exploited to construct interconnected meso-macroporous structure. The rice husk carbon (RHC) presents a foam-like morphology with unprecedented porosity that has not been reported before.The meso-macroporous structure of RHC is highly correlated with the degree of RH pyrolysis, demonstrating that the pore structure originates from the pyrolysis process. In addition, due to the abundant oxygen-containing functional groups on pyrolyzed RH, the amount of NaOH used for subsequent activation is much lower compared with previous works. Due to the interconnected meso-macroporous channels, RHC materials display exceptional adsorption capacity and fast diffusion rate, exceeding CMK-3, a typical mesoporous carbon material.

Plastics are widely used in daily life and industry. However, the natural degradation of waste plastics is very slow, causing considerable environmental problems. Catalytic cracking is able to convert waste plastics into fuels and chemicals, being an efficient and sustainable utilization route for waste plastics. Zeolites are commonly used as catalysts for this process, with the performance mainly affected by diffusion and acidity properties. It is necessary to elucidate the combinatorial effect of these two factors. Herein, zeolite Beta was used as the model catalyst for the catalytic cracking of low-density polyethylene (LDPE). The synergistic effect of diffusion and acidity on the catalytic performance was explored by systematically controlling the Si/Al ratio (SAR) and particle size of zeolite Beta. By correlating the acidity and pore structure of Beta zeolites with the catalytic performance, a gasoline yield descriptor - gasoline factor (GF) was proposed, and GF fitted well with the gasoline yields of LDPE cracking by Beta zeolites, demonstrating that GF may provide theoretical guidance for the optimized design of zeolite catalysts in the LDPE cracking. Through fine analysis of the gasoline composition with M4 multidimensional chromatography, for the first time, a high proportion of cyclo-olefins was discovered in the gasoline products of all zeolite catalysts, which was ascribed to the unique long hydrocarbon chains of LDPE. Considering that cyclo-olefin copolymers possess high thermal stability and excellent chemical resistance, the cyclo-olefin monomers produced by the cracking of LDPE exhibit high potential in commercial applications.

Propane dehydrogenation (PDH) is a vital petrochemical process. As an alternative to Pt and Cr-based catalysts, Ni-based catalysts used in PDH, however, exhibit low propylene selectivity with severe coking. This work aims to understand the role of different Ni species in PDH and achieve high propylene selectivity by inhibiting coking. Specifically, we obtained NiOx/Al2O3 catalysts with solely tetrahedrally coordinated Ni2+ (Ni-IV) by selectively removing microcrystalline NiOx using the impregnation-complexation strategy. The Ni sigma+ species derived from Ni-IV exhibited high propylene selectivity (similar to 88 %) and low coke yield (2.26 %) in PDH. In contrast, reducing microcrystalline NiOx to Ni-0 resulted in high methane selectivity and high coke yield (14.90 %). Theoretical calculations and experimental results indicate that this difference is attributed to the faster propylene desorption from Ni sigma+ as compared to that from Ni-0. Therefore, catalysts with well-confined Ni sigma+ are selective in PDH. This study offers a rational strategy for designing Ni-based PDH catalysts.

An environmentally friendly clay stabilizer ZWS-2 was synthesized by the reaction of γ-（2,3-epoxypropoxy） propyltrimethoxysilane（KH560） with trimethylamine hydrochloride. The anti-swelling performance and washing resistance of clay stabilizer under different conditions were studied. It is found that the optimum synthesis conditions are as follows: the molar ratio of KH560 to trimethylamine hydrochloride is 1.1∶1, the reaction temperature is 70 ℃, and the reaction time is 6 h. The anti-swelling rate of ZWS-2 aqueous solution with mass fraction of 4% is 96.6% at 150 ℃ and 90.3% at 300 ℃. The optimal compounding scheme is 1.5% ZWS-2 + 4% KCl. After compounding with the main agent of slippery hydraulic fracturing fluid, the anti-swelling rate is 99.6% and the 1st washing resistance rate is 99.5%.

为强化工科学生的工程意识,满足柴油超深度加氢脱硫催化剂载体的性能要求,作者系统设计了富B酸载体材料合成大学生创新实验,并进行教学实践.实践结果表明,市场调研与环境评估环节可以培养学生的实践意识,文献查阅与催化剂设计环节可以培养学生的创新能力,催化剂载体制备与表征环节可以培养学生的动手能力,团队协作过程可以培养学生的合作意识,实验风险评估环节可以培养学生的安全意识.从市场调研到催化剂设计,从实验设计、原料处理到材料制备和风险评估,一体化的实验教学过程增强了学生的工程意识,使学生在解决问题的过程中锻炼了创新能力.

Well-dispersed PdIn bimetallic alloy nanoparticles (1-4 nm) were immobilized on mesostructured silica by an in situ capture-alloying strategy, and PdIn-In2O3 interfaces were rationally constructed by changing the In2O3 loading and reduction temperature. The catalytic performance for benzyl alcohol partial oxidation was evaluated, and a catalytic synergy was observed. The Pd-rich PdIn-In2O3 interface is prone to be formed on the catalyst with a low In2O3 loading after being reduced at 300 °C. It was demonstrated that the Pd-rich PdIn-In2O3 interface was more active for benzyl alcohol partial oxidation than In-rich Pd2In3 species, which was likely to be formed at a high reduction temperature (400 °C). The high catalytic activity on the Pd-rich PdIn-In2O3 interface was attributed to the exposure of more Pd-enriched active sites, and an optimized PdIn-In2O3/Pd assemble ratio enhanced the oxygen transfer during partial oxidation. The density functional theory (DFT) calculation confirmed that the Pd-rich Pd3In1(111)-In2O3 interface facilitated the activation of oxygen molecules, resulting in high catalytic activity.

The improvement of methyl lactate yield was achieved by constructing water-tolerant Lewis acid sites, which were generated by reducing hydroxyl groups and increasing coordinatively unsaturated sites.

为了实现氢键的"可视化",加强本科生理论联系实践的能力,系统地设计了低共熔溶剂体系的建立与应用综合型教学实验,并通过大学生创新实验的形式对该教学内容进行了实践教学.实践结果表明,从实验方案设计、配体的选择、低共熔溶剂的配制及苯甲醇的萃取分离一体化的实验设计,可以把抽象的理论转化为直观的现象,"看见"氢键的存在.实验过程不仅可以加强学生对基础理论知识的理解,而且能够拓展学生的科学思维,有利于本科生实践创新能力的培养.

Ordered “nest-like” hierarchical ZSM-48 (NSH-ZSM-48) hollow spheres stacked by uniform nanorods with superior accessibility were synthesized utilizing a novel bolaform s-triazine based surfactant, and the proper formation mechanism was proposed.

A series of γ-Al2O3 supported gold-palladium (Au-Pd) alloy nanoparticles (NPs) catalysts were synthesized by a one-pot approach applying mercapto-propyl-trimethoxysilane (MPTMS) as an anchoring ligand. Homogeneously dispersed Au-Pd alloy NPs were observed on the prepared catalysts and their catalytic performance in benzyl alcohol partial oxidation was investigated. Results showed that the highest benzaldehyde yield was achieved on catalyst Au-Pd/7%MPTMS-γ-Al2O3 with a benzaldehyde selectivity of 90%. By establishing the structure-performance relationship, the high activity of catalysts with MPTMS modification was attributed to the anchoring and dispersion effect of MPTMS on Au-Pd NPs, while the high benzaldehyde selectivity was due to the formation of more surface Lewis acid sites after introducing MPTMS, protecting the benzaldehyde from over-oxidation to byproducts.

为强化学生的"碳中和"理念和科研创新能力,文章设计了过渡金属硫化物基光敏剂制备及光催化性能综合型教学实验,并通过大学生创新实验形式对该教学内容进行了实践教学.实验教学结果表明:通过对近红外光催化剂制备、结构和光化学性质表征及性能评价等多个环节的设计,使学生切身感受到了光能的魅力;通过探讨光催化过程中选择性氧化的机理,加深了学生对光催化理论知识的理解,激发了他们的科研兴趣,促进了他们创新能力的提升.

Zeolite exhibits excellent catalytic performance in the catalytic cracking of polyolefins, but the reaction results are often controversial due to the differences in the lab-scale synthesized zeolites and the types of reactors selected. In this work, in order to eliminate the differences of catalysts synthesized by individual researchers, we studied the catalytic performance of four typical commercial zeolites (HZSM-5, Hβ, HY and SAPO-11) in the cracking of low-density polyethylene (LDPE) by self-designed batch reactor. By comparing the reaction performance of four zeolites under the same condition and correlating with the pore structure and acidity of the zeolites, it was found that the acid strength of zeolites was positively correlated with the cracking conversion. HZSM-5 and Hβ zeolites with high acid strength achieved a LDPE conversion of above 94%. Large micropore is beneficial to the formation of isomerized products, but promotes the formation of coke precursors, resulting in serious coking. By analyzing the product distribution over different zeolites, it was observed that Hβ achieved the highest yield of gasoline components. HZSM-5 and HY exhibited high yields of aromatization products. The high aromatization activity of HZSM-5 was attributed to its strong acidity which enhanced the hydrogen transfer process, while HY possesses high concentrations of both Brönsted and Lewis acid sites, and the synergistic effect of these two acid sites promotes the aromatization process.

The VOX/Al2O3 is known as an active catalyst in the propane dehydrogenation, however, with poor stability due to the severe coking problem. In this study, the VOX/Al2O3 catalyst was modified by boric acid, and the catalyst exhibited significantly improved stability and less coke deposition than the unmodified counterpart. The experimental results and theoretical modeling (DFT) suggested that the boron decreased the polymerization degree of VOX species, generated a high proportion of isolated vanadium species that reduced the initial activity but enhanced the stability of VOX/Al2O3 catalyst. Boron interacted with Al and V forming B-O-Al and B-O-V bonds, which significantly reduced the amounts of both Brønsted and Lewis acid sites, alleviating the coke deposition rate on the catalyst surface. The boron on VOX/Al2O3 promoted the desorption of propylene that inhibited further cracking and its polymerization, thus improving the propylene selectivity and catalyst stability.