CHINESE JOURNAL OF CATALYSIS
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2020
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IF 6.146
Xiaona Liu,Yi Cao,Nana Yan,Chao Ma,Lei Cao,Peng Guo,Peng Tian,Zhongmin Liu
The high-temperature (HT) and low-temperature (LT) hydrothermal stabilities of molecular-sieve-based catalysts are important for the selective catalytic reduction of NO x with ammonia (NH 3 -SCR). In this paper, we report a catalyst, Cu 2+ loading SAPO-17, synthesized using cyclohexylamine (CHA), which is commercially available and inexpensive and is utilized in NH 3 -SCR reduction for the first time. After systematic investigations on the optimization of Si and Cu 2+ contents, it was concluded that Cu-SAPO-17-8.0%-0.22 displays favorable catalytic performance, even after being heated at 353 K for 24 h and at 973 K for 16 h. Moreover, the locations of CHAs, host–guest interaction and the Brönsted acid sites were explored by Rietveld refinement against powder X-ray diffraction data of as-made SAPO-17-8.0%. The refinement results showed that two CHAs exist within one eri cage and that the protonated CHA forms a hydrogen bond with O4, which indicates that the proton bonding with O4 will form the Brönsted acid site after the calcination .
研究领域:
催化化学
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环境科学
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材料科学
✓ 已验证
DOI
高影响因子
Inorganic Chemistry Frontiers
·
2023
·Vol. 10
·期 15
·4519-4525
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IF 7
Chaoran Wang,Xiao Li,Shiyue Liu,Tingting Wang,Puxu Liu,Xiaowei Song,Zhiqiang Liang
Silicoaluminophosphate (SAPO) zeolites with small pores (8-ring window), such as SAPO-34, SAPO-17, and SAPO-RHO, have attracted a lot of attention due to their unique structural features, and their applications in the field of small-molecule gas adsorption and separation. However, the fast, efficient and green synthesis of SAPO zeolites remains a great challenge. In this work, SAPO-17 zeolites were synthesized within 1 min for the first time by a seed-assisted microwave method, and the resulting samples possessed excellent performance in the application of CO2 adsorption and separation for flue gas and natural gas. The microwave-assisted route can shorten the crystallization time of traditional hydrothermal methods from a few hours to 30 min. Furthermore, the crystallization time could be drastically shortened to 1 min with the addition of seeds, which represents the shortest time for the preparation of a SAPO-17 zeolite up to now. SAPO-17 synthesized within 1 min (SAPO-17-S-1) possessed the smallest crystal size, and the largest micropore volume and specific surface area among all the samples, which enhanced mass transfer and exposed more active sites, and thus it possessed prominent performance for CO2 adsorption (3.47 mmol g−1 at 273 K and 1 bar) and gas separation. At 298 K and 100 kPa, SAPO-17-S-1 exhibited the highest gas selectivity for CO2/N2 (276) and CO2/CH4 (63) over the other samples, which were synthesized in a relatively long time. Transient binary breakthrough experiments on SAPO-17-S-1 further verified the highly-efficient gas separation performance. This work proposes a green and ultrafast strategy for the synthesis of SAPO-17 zeolites with highly selective CO2 adsorption over N2 and CH4.
研究领域:
材料科学
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环境科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
CHINESE JOURNAL OF CATALYSIS
·
2025
·
IF 17.7
Ye Wang,Pan Gao,Dan Zhao,Tongrui Liu,Sitong Zhou,Miao Yang,Shiping Liu,Bing Li,Yida Zhou,Wenhao Cui,Guangjin Hou,Peng Tian,Zhongmin Liu
Silicoaluminophosphate (SAPO) molecular sieves possess diverse architectures and exceptional high-temperature hydrothermal stability, rendering them important acid catalysts. However, enhancing acid concentration of certain SAPO materials remains challenging, which limits their catalytic applications. Here, we report the synthesis of a series of SAPO materials using a developed SAPO precursor plus dual template (SPDT) strategy. A variety of SAPO materials characterized by high silica content and enhanced acidity, such as SAPO-34/56 intergrowths, SAPO-56, and SAPO-17, have been synthesized and thoroughly characterized using various techniques including integrated differential phase-contrast scanning transmission electron microscopy, two-dimensional solid-state nuclear magnetic resonance spectroscopy, and continuous rotation electron diffraction. The use of silica-enriched SAPO precursor combined with the flexible selection of the second template enables the crystalline phase regulation and improves the Si atoms incorporation into the framework. Notably, the synthesized SAPO-17 with abundant Si(4Al) species and unprecedentedly high acid density exhibits exceptional DeNO x activity after Cu loading, with NO x conversion exceeding 90% at 175–700 °C. This outstanding performance can be attributed to the unique ERI structure and the increased acidity of SAPO-17. This work not only presents an effective method for synthesizing SAPO molecular sieves with enhanced acidity but also offers a new perspective for expanding the active temperature range of the ammonia selective catalytic reduction reaction.
研究领域:
材料化学
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催化化学
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无机非金属材料
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环境催化
·
分子筛科学
✓ 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）