CATALYSIS LETTERS
·
2011
·Vol. 141
·期 12
·1821-1827
·
IF 1.907
Duan Chao,Zhang Xin,Zhou Rui,Hua Yuan,Chen Jie,Zhang Li
HZSM-5/SAPO-34 zeolite composites were prepared by hydrothermal synthesis (ZS-HS) and mechanical mixture (ZS-MM), respectively. ZS-HS showed higher propylene yield and better catalytic stability in ethanol conversion than ZS-MM as well as HZSM-5 and SAPO-34. In case of ZS-HS, SAPO-34 at least partially overlapped on HZSM-5, which resulted in the interfacial interaction of HZSM-5 and SAPO-34. Such interaction significantly modified the texture and the acidity of ZS-HS, which in turn affected its catalytic reactivity. ZS-HS showed the higher apparent formation rate of propylene, due to its moderate concentration and strength distribution of acid sites. Propylene, ethylene and butylenes might produce through the parallel reaction pathways and the common intermediate on ZS-HS. Graphical [Time course of ethanol conversion on ZS-HS and ZS-MM catalysts.]
✓ 已验证
DOI
高影响因子
JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY
·
2014
·Vol. 14
·期 9
·6900-6906
·
IF 1.339
Chu Yue,Zhang Qiang,Wu Tongwei,Nawaz Zeeshan,Wang Yao,Wei Fei
Ultra-dispersed precious metal nanoparticles with good thermal stability are highly required for heterogeneous catalysis. However, the efficient and effective strategy to disperse ultra-fine precious metal nanoparticles at high reaction temperature is still not fully understood yet.
In this contribution, a family of catalysts with ultra-small Pt nanoparticles were prepared using impregnation method by adjusting the zeolite content in the SAPO-34 and γ-Al2O3 mixed support. The effect of Pt nanoparticle size on the catalytic activity,
selectivity, and stability was investigated in the propane dehydrogenation reaction. Catalyst with smaller Pt particles exhibits better catalytic performance. Both the highest Pt dispersion and the best catalytic activity can be achieved by using SAPO-34 and γ-Al2O3
mixed support with 70 wt.% of SAPO-34. The size and structure of the Pt nanoparticles on the optimal catalyst were characterized by transmission electron microscopy. Pt nanoparticles with an average size of 1.32 nm were observed. There were stronger metal-support interactions between the oxidized
tin species and Pt particles on SAPO-34 support compared to that on γ-Al2O3 catalyst. These lead to high Pt dispersion and consequently good catalytic performance.
研究领域:
催化化学
·
材料科学
·
化学工程
·
纳米技术
·
多相催化
✓ 已验证
DOI
高影响因子
FUEL PROCESSING TECHNOLOGY
·
2022
·
IF 8.129
Hao Qin,Nengjie Feng,Quan Lv,Hui Wan,Guofeng Guan
Single atomic catalysts (SAC) isolated in zeolite have been reported for hydroisomerization of n-alkanes. However, it is widely found that metal species located outside zeolite crystals have beneficial effects on catalytic performance, rather than inside zeolite. Herein, we introduce cerium oxide as a binder to anchor Pt single atoms on the catalyst surface . Pt species were atomically dispersed on catalyst surface certified by AC HAADF-STEM and XAS. Pt 1 @CeO x /SAPO-11 not only shows significant activity but also effectively inhibits the selectivity of cracking or hydrogenolysis . The turnover frequency value of 0.05%Pt 1 @CeO x/ SAPO-11 reaches 9511 h −1 , 13 times higher than reported catalyst prepared with the space-confined strategy. Reaction mechanisms have been proposed to explain the different effects of platinum status and location on the reaction. Platinum single atoms located outside the catalyst crystal are speculated more favourable to this reaction. Conceptually, catalytic efficiency of this reaction can be improved by dispersing the active sites to reduce the local concentration of the product of a reversible step in an intermediate reaction. An appropriate loading of 0.05 wt% is needed to achieve the high efficiency of the metal and acid sites simultaneously.
研究领域:
催化
·
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2018
·
IF 5.091
Yuxiang Liu,Yuchao Lyu,Baojie Wang,Yi Wang,Xinmei Liu,Mark J. Rood,Zhen Liu,Zifeng Yan
It is important to develop new promoters of fluid catalytic cracking (FCC) catalyst to increase iso-paraffin yield and avoid the decrease of research octane number (RON) caused by olefin saturation in gasoline hydrofining. SAPO-11 and LaAPO-11 molecular sieves were used as promoters to FCC catalyst to increase gasoline RON and were tested in the cracking reaction of n-dodecane on FCC conditions. LaAPO-11 molecular sieve has less and weaker acidity than SAPO-11 molecular sieve. LaAPO-11’s metallic sites polarize the C H bonds to form carbenium ions for isomerization reaction and weak acid sites make less contributions to the cracking of iso-paraffin. LaAPO-11 promoter increases the yield of iso-paraffin (C 5-9 ) from 6.4% to 10.2%. Besides that, a high yield of arene (2.0%) is caused by the dehydrogenation activity of LaAPO-11 promoter. The new contributions of this paper are the synthesis of a hydrothermal stable LaAPO-11 molecular sieve with isomerization activity and proposing the reaction routes of iso-paraffin. These new contributions are important for developing more effective RON promoters of FCC catalyst.
研究领域:
化学工程
·
催化材料科学
✓ 已验证
DOI
高影响因子
APPLIED ENERGY
·
2017
·
IF 7.182
Xiaowen Zhang,Xin Zhang,Helei Liu,Wensheng Li,Min Xiao,Hongxia Gao,Zhiwu Liang
In this work, the regeneration of rich CO 2 -loaded monoethanolamine (MEA) solvent with two catalysts (e.g. SAPO-34 and SO 4 2− /TiO 2 ) was investigated in order to reduce the energy requirement for solvent regeneration. The regeneration behavior with and without catalyst of a 5M MEA solution with an initial CO 2 loading of 0.5 mol CO 2 /mol amine at 96 °C was studied to compare their CO 2 desorption rate and heat duties. The results show that the two solid acid catalysts can reduce the heat duty for solvent regeneration and increase the CO 2 desorption rate in comparison with blank test. The mechanism of CO 2 desorption with catalyst in 5M MEA was proposed based on the result of catalyst characterization (e.g. N 2 absorption/desorption experiment, Py-IR, NH 3 -TPD, FT-IR and XRD) to better understand the desorption process. The results indicate that SAPO-34 with the higher joint value of Brϕnsted/Lewis acid sites ratio (B/L) and mesopore surface area (MSA) shows the faster CO 2 desorption rate and lower heat duty than SO 4 2− /TiO 2 . Based on the experimental results, the addition of solid acid catalysts into amine solution could be considered as one of choices to reduce the heat duty for CO 2 desorption from CO 2 -loaded amine solvent.
研究领域:
化学工程
·
环境科学
·
催化
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2021
·
IF 3.764
Xiaonan Zhao,Wei Liu,Xiufeng Liu,Baoquan Zhang
Mixed matrix membranes (MMMs) are challenged by the poor compatibility between fillers and a polymer matrix that leads to the weakened performance for gas separation. The surface modification of fillers with aminosilane should be an effective approach to improve their compatibility within the polymer matrix. 3-(2-Aminoethylamino)propyl-dimethoxymethylsilane (APDS) was used as a silane coupling agent for modification of sheet-like silicoaluminophosphate-34 (SAPO-34) crystal grains, and novel MMMs were fabricated by incorporating APDS-modified SAPO-34 crystal grains into a Pebax MH 1657 polymer. Based on characterization using scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and mechanical tests, the incorporation of an APDS-modified SAPO-34 into Pebax matrix led to much enhanced interfacial adhesion within the MMM. In addition, the effect of the filler content in the MMM on the separation performance of a CO2/CH4 gas mixture and pure gases (CO2 and CH4) was investigated. Compared with available Pebax-based MMMs in the literature, the prepared MMM containing 8 wt % APDS-modified SAPO-34 exhibited the satisfactory CO2 permeability of ca. 137 Barrer and the highest selectivity of 34.7 for the CO2/CH4 gas mixture. It was believed that the excellent separation performance and good stability of the prepared MMM in this study should be due to the good interfacial compatibility of APDS–SAPO-34 fillers together with their strong affinity for CO2 within the MMM.
研究领域:
材料科学
·
化学工程
·
膜技术
✓ 已验证
DOI
高影响因子
ACS Catalysis
·
2025
·
IF 13.1
Chun-Mu Guo,Ming-Hui Sun,Zhan Liu,An-Kang Jiang,Bo Ye,Chang Xu,Xiao-Yu Yang,Bao-Lin Sun,Ying Jiang,Wei Wu,Xiao-Yun Li,Yu Li,Li-Hua Chen,Bao-Lian Su
The persistent challenge of catalyst deactivation in methanol-to-olefins (MTO) conversion, primarily arising from restricted molecular transport and subsequent coke accumulation in conventional microporous SAPO-34 zeolites, necessitates innovative structural solutions. Herein, we demonstrate a synthesis strategy that employs sucrose-derived carbon as a hard template combined with vapor-phase transport to fabricate hierarchical SAPO-34 single crystals, thereby overcoming the low crystallinity and poor pore connectivity that have previously plagued hierarchical SAPO-34 zeolites. This intracrystalline hierarchical architecture with highly interconnected pores demonstrates molecular highway functionality and exhibits a 77.5% increase in propylene diffusion coefficient compared to conventional samples. Such hierarchical molecular highway architecture effectively regulates coke distribution within SAPO-34 crystals during MTO reactions. The optimized hierarchical SAPO-34 exhibits a 505 min operational lifetime, a 3.3-fold enhancement in catalytic durability over traditional microporous systems. Our findings establish a materials design paradigm for overcoming diffusion-reaction trade-offs in zeolite catalysis, with implications extending beyond conventional MTO processes.
✓ 已验证
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2023
·
IF 9.5
Xi Chen,Nana Wang,Guining Chen,Zhenggang Wang,Gongping Liu,Rongfei Zhou,Wanqin Jin
Mixed-matrix formulation is a promising method to overcome permeability-selectivity trade-off of polymers with incorporation of fillers with well-defined nanopores . The filler properties play a key role in determining the performance of mixed-matrix membrane (MMM). In this work, for the first time, we explored the critical effect of filler structural integrity on separation performance of MMM. Typically, micron as-synthesized, submicron as-synthesized and submicron ground SAPO-34 zeolites were incorporated into 6FDA-DAM polyimide , respectively. The interface compatibility between two phases was ensured by (3-aminopropyl) trimethoxysilane (APTMS) modification on SAPO-34 fillers. It was found that the directly synthesized micron and submicron fillers contributed to enhance the CO 2 /CH 4 separation performance whereas the submicron ground filler lowered the CO 2 permeability. Notably, incorporating 30 wt% micron as-synthesized SAPO-34 into 6FDA-DAM enhanced the CO 2 permeability by 68% and CO 2 /CH 4 by 37%, surpassing the performance upper-bound. Moreover, the hydrogen bonding between the filler and polymer matrix endowed the membrane with outstanding plasticization resistance with CO 2 partial pressure up to 20 bar. Adsorption isotherms and Maxwell model prediction revealed that the filler transport properties could be significantly affected by commonly-used methods of reducing the filler size. A decreased structural integrity was identified in the sequence of micron as-synthesized, submicron as-synthesized and submicron ground fillers. This work highlights the importance of a careful balance between structural integrity and crystal size of filler, and reliable routes to obtain nanofillers with desirable structural integrity as pursuing high-performing MMM toward practical application.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
ACS Applied Nano Materials
·
2026
·
IF 5.8
Yihang Jiang,Xia Zhang,Wenzhi Li,Liang Yuan
Low-concentration coalbed methane, an underused energy resource, poses environmental risks due to its potent greenhouse effect upon direct atmospheric release, creating an urgent need for efficient utilization. Converting methane to methanol offers a viable solution to this challenge. This research examines how the silicon content affects the catalytic activity of Cu/SAPO-34 in the continuous direct oxidation of methane into methanol. Yield and selectivity of methanol exhibit a distinct volcano-shaped dependence on silicon content, among which Cu/SA2 showed excellent activity and selectivity, achieving a space-time yield of methanol 293.6 ± 5.9 μmol/(gcat·h) and selectivity 78.9% ± 1.5%. Silicon content tunes SAPO-34’s acid site distribution and silicon coordination environment, which govern copper species anchoring during solid-state ion exchange. Moderate silicon content promotes the optimized dispersion of copper species, effectively enhancing the content of isolated Cu2+ active sites. In situ DRIFTS elucidates the methane activation mechanism involving Cu(I)-methyl intermediates, along with the critical role of trace oxygen (1000 pm) and water vapor in promoting the catalytic redox cycle of the active sites. This work clarifies the zeolite composition–activity relationship, guiding rational design of high-performance catalysts for methane valorization.
✓ 已验证
产品关联
DOI
高影响因子
Petroleum Science
·
2021
·Vol. 18
·期 2
·654-666
·
IF 4.09
Wen Cheng-Long,Xu Jun-Dong,Wang Xue-Man,Fan Yu
To enhance the gasoline octane number, low-octane linear n-alkanes should be converted into their high-octane di-branched isomers via n-alkane hydroisomerization. Therefore, hierarchical SAPO-11-based catalysts are prepared by adding different contents of sodium dodecylbenzene sulfonate (SDBS), and they are applied in n -nonane hydroisomerization. When n (SDBS)/ n (SiO 2 ) is less than or equal to 0.125, the synthesized hierarchical molecular sieves are all pure SAPO-11, and as the SDBS content increases, the submicron particle size decreases, and the external surface area (ESA) increases. Additionally, these hierarchical SAPO-11 have smaller submicron particles and higher ESA values than conventional SAPO-11. When n (SDBS)/ n (SiO 2 ) is greater than 0.125, with increasing SDBS content ( n (SDBS)/ n (SiO 2 ) = 0.25), the synthesized SAPO-11 contains amorphous materials, which leads to a decline in the ESA; with the further increase in SDBS content ( n (SDBS)/ n (SiO 2 ) = 0.5), the products are all amorphous materials. These results indicate that in the case of n (SDBS)/ n (SiO 2 ) = 0.125, the synthesized SAPO-11 molecular sieve (S–S 3 ) has the most external Brønsted acid centers and the highest ESA of these SAPO-11, and these advantages favor generation of the di-branched isomers in hydrocarbon hydroisomerization. Among these Pt/SAPO-11 catalysts, Pt/S–S 3 displays the highest selectivity to entire isomers (83.4%), the highest selectivity to di-branched isomers (28.1%) and the minimum hydrocracking selectivity (15.7%) in n -nonane hydroisomerization.
研究领域:
催化化学
·
石油化工
·
材料科学
·
多相催化
✓ 已验证
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2025
·
IF 4.7
Panpan Zhai,Yapeng Li,Zhipan Liu,Zhanling Ma,Dehua Wang,Beibei Gao
A series of hierarchical SAPO-34 molecular sieves were successfully synthesized through the organosilane-assisted method, employing low-cost 3-aminopropyltriethoxysilane (APTES) as a mesoporous template and partial silica source. The influence of APTES content on the crystallinity, pore structures, acidity, and catalytic performance of the products in the methanol-to-olefins (MTO) reaction was systematically investigated by XRD, XRF, SEM, N 2 adsorption-desorption, NH 3 -TPD measurements and a fixed-bed reactor. It revealed that the introduction of APTES created mesopores and simultaneously modulated the acidic properties, notably reducing both the strength and density of strong acid sites. Compared to the conventional microporous SAPO-34-C, the hierarchical SAPO-34 catalysts, particularly SAPO-34-0.1, demonstrated a superior catalytic lifetime and enhanced selectivity to light olefins in the MTO reaction. This performance enhancement could be attributed to their hierarchical pore systems and the moderated acidities. However, excessive APTES addition (SAPO-34-0.2) led to a decline in crystallinity and a consequent reduction in catalytic stability.
研究领域:
催化化学
·
材料科学
·
化学工程
·
多孔材料
·
多相催化
✓ 已验证
产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2025
·
IF 2.5
Yi Xiang,Zidan Mei,Lulu Zhou,Yue Li,Yongdong Chen
The hydrogenation of CO2 to light olefins is a promising method for CO2 resource utilization. Tandem catalysts composed of metal oxides and zeolites have been widely studied for the hydrogenation of CO2 to light olefins, but there are bottleneck problems in terms of CO2 conversion and light olefins yield. ZnO-ZrO2 catalyst is extensively employed in CO2 hydrogenation because of its excellent stability at high temperatures, but there is still a "seesaw" problem between the CO2 conversion and light olefins selectivity. In addition, the synergetic effect between Zn and Zr sites on the reaction process remains unclear. In this work, a series of ZnO-ZrO2 catalytic materials with various Zn: Zr ratios were synthesized by co-precipitation, and the interaction between Zn and Zr could be regulated by altering the Zn: Zr ratio. XRD and TEM results confirmed the successful synthesis of ZnO-ZrO2 composite oxide and the existence of a certain interaction between Zn and Zr. CO2-TPD, H2-TPR and XPS results indicated that the interaction between Zn and Zr could improve the hydrogenation capacity of the catalyst and also induce the generation of abundant oxygen vacancies to effectively promote the adsorption and activation of CO2. Catalytic performance results showed that ZnO-ZrO2(1:4)/SAPO-34 exhibits the best CO2 to light olefins activity with a CO2 conversion rate of 26.4% and a C2=-C4=selectivity of 72.6%. This work provides a feasible strategy for rational designing and optimizing of CO2 hydrogenation catalyst.
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）