CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Huihui Deng,Baozhen Li,Wenchun Zheng,Qin Sun,Mengjia Zhu,Jun Zuo,Yu Tang,Lizhi Wu,Li Tan
Propane dehydrogenation is one of the most promising routes for propylene production due to its single reactant, product and high economic efficiency. For Co-based catalysts, the state of Co species is one of the important factors affecting the performance of propane dehydrogenation. Here, we designed zeolite Silicalite-1 (S-1) with different silanol nests content as support to investigate the effect of silanol nests content to form Td-Co(II) species. It is found that the content of silanol nests in the S-1 supports have a linear correlation with the formation of T d -Co(II) species and corresponding PDH catalytic activity through the study of the catalyst structure-performance relationship. And the silanol nests of S-1 could be fully coordinated with 0.5 wt% Co content over 0.5Co/S-1-1-HTS in the form of T d -Co(II) species to maximize the Co atomic utilization. Correspondingly, 0.5Co/S-1-1-HTS shows the most excellent catalytic activity and stability, with C 3 H 6 generation rate of 3014 mmol C 3 H 6 g Co −1 h −1 and deactivation rate of 0.07 h −1 at 550 °C.
研究领域:
化学工程
·
催化科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS A-GENERAL
·
2022
·
IF 5.723
Guoqiang Hou,Tingjun Fu,Xin Li,Qian Ma,Zhong Li
HZSM-5 catalysts with abundant silanol nests were fabricated by removing framework Al, which effectively promoted the selective alkylation of toluene with methanol by inhibiting the deep alkylation of aromatics to heavy aromatics and the conversion of methanol to light hydrocarbons. Correspondingly, the alkylation efficiency reached 65.3% at a toluene conversion of 31.3% over dealuminated HZSM-5, higher than the 55.2% efficiency and 28.0% conversion of parent zeolites, respectively. In situ DRIFTS and single-factor experimental clarified that toluene adsorption was enhanced and methanol to hydrocarbons was inhibited with the presence of silanol nests. Additionally, by increasing the crystal size of HZSM-5 with silanol nests from 2 to 5 µm, para-xylene selectivity was increased from 36.1% to 65.5% because of the enhanced diffusion barrier . The finding of the positive effect of the silanol nests on toluene alkylation can provide a solid fundamental basis for the rational design of catalysts.
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Nature Communications
·
2023
·Vol. 14
·期 1
·1-9
·
IF 16.6
Liu Yifeng,Liu Zhiqiang,Hui Yu,Wang Liang,Zhang Jian,Yi Xianfeng,Chen Wei,Wang Chengtao,Wang Hai,Qin Yucai,Song Lijuan,Zheng Anmin,Xiao Feng-Shou
Hydroformylation is one of the largest industrially homogeneous processes that strongly relies on catalysts with phosphine ligands such as the Wilkinson’s catalyst (triphenylphosphine coordinated Rh). Heterogeneous catalysts for olefin hydroformylation are highly desired but suffer from poor activity compared with homogeneous catalysts. Herein, we demonstrate that rhodium nanoparticles supported on siliceous MFI zeolite with abundant silanol nests are very active for hydroformylation, giving a turnover frequency as high as ~50,000 h −1 that even outperforms the classical Wilkinson’s catalyst. Mechanism study reveals that the siliceous zeolite with silanol nests could efficiently enrich olefin molecules to adjacent rhodium nanoparticles, enhancing the hydroformylation reaction.
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INORGANIC CHEMISTRY
·
2025
·
IF 4.7
Muchun Zhang,Chengqin Zhong,Huifang Wu,Xin Yan,Siyang Yan,Jingfeng Han,Xiang Wang,Jiaxu Liu,Limin Ren
Self-pillared pentasil (SPP) zeolites show great promise for sustainable catalysis but face challenges in stabilizing strong Lewis acid (L-acid) sites due to weak metal-surface interactions. This study develops an “energy-driven migration” strategy to construct confined Zr-Lewis acid sites through defect engineering of boron-containing SPP precursors. By combining controlled Zr grafting with subsequent nitric acid treatment, we achieved selective deboronation to generate tailored silanol nests, directing the migration of surface Zr species into framework-confined sites. DFT calculations confirmed that silanol defects provide a strong thermodynamic driving force for Zr migration (ΔE of −14.7 eV). Through regulation of the boron content and nanosheet thickness, we achieved precise control over Zr migration while balancing efficient mass transfer and site stabilization. The optimized Zr-SPP catalyst exhibits exceptional performance in Meerwein–Ponndorf–Verley (MPV) reduction of cyclohexanone (97% conversion, TOF = 11.28 h–1), a 12-fold improvement over surface-type counterparts. Key design principles, including dissociable Zr precursors, acid-induced migration, silanol nest density optimization, and nanosheet thickness regulation, are identified as being critical for stabilizing active sites. The universality of this strategy is further validated in BEA zeolites, establishing silanol nest engineering as a general paradigm for designing durable l-acid catalysts in biomass valorization and green chemistry applications.
研究领域:
催化
·
材料科学
·
绿色化学
·
化学工程
·
理论化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FUEL
·
2023
·
IF 7.4
Jiaxing Zhang,Songcheng Bo,Weiping Liao,Kaixuan Yang,Ting Su,Hongying Lü,Zhiguo Zhu
As robust heterogeneous catalysts, stannosilicate zeolites (in particular Sn-Beta) exhibit excellent catalytic performance in aqueous Baeyer-Villiger oxidation due to their unique activation ability of carbonyl group. For a specific Sn-containing zeolite, pore-engineering and hydrophobicity are generally two coupled factors to impact catalytic behavior. How to distinguish the function of each factor in this selective oxidation is still a pending question. Bearing this in mind, five stannosilicate zeolites (Sn-MFI, Sn-MWW, Sn-Beta, Sn-MCM-41, and Sn-Y) were prepared to establish the relationship between the structure (Lewis acidity, pore-engineering, and hydrophobicity) and catalytic performance. Particularly, hierarchical Sn-Y zeolite was post-synthesized by a simple solid-state ion-exchange method, where Sn 4+ ions were incorporated into zeolite framework via reacting with silanol nests derived from dealumination process. In comparison with other stannosilicate zeolites, the obtained Sn-Y possessed excellent catalytic activity in Baeyer-Villiger oxidation irrespective of using aqueous hydrogen peroxide or bulky tert -butyl hydroperoxide as the oxidant. Structure-performance relationship revealed that Lewis acid site was the catalytically active center and the catalytic activity was depended on zeolite pore-engineering and hydrophobicity in aqueous B-V oxidation system. The relatively high catalytic activity of Sn-Y zeolite was ascribed to its excellent hydrophobicity and opened channel system. The former can be further enhanced by silanization treatment. Finally, the recyclability and deactivation mechanism were given insight. This work is aimed to provide some guidance for elaborately designing efficient stannosilicate zeolite catalyst for Baeyer-Villiger oxidation by precisely modulating pore-engineering and hydrophobicity.
研究领域:
催化
·
材料科学
·
化学工程
·
无机化学
✓ 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）