MICROPOROUS AND MESOPOROUS MATERIALS
·
2016
·
IF 3.349
Xiaopeng Zhang,Hua Wang,Xiao Liu,Jinyu Han,Xinli Zhu,Qingfeng Ge
Co/NaY catalysts prepared by impregnation of NaY with a cobalt nitrate-ethanol solution were used to catalyze liquid-phase hydrogenation of ethyl lactate to 1,2-propanediol (1,2-PDO). To elucidate the effect of calcination conditions and cobalt loading, the catalysts were characterized using XRD , N 2 physical adsorption, H 2 -TPR, XPS , H 2 -TPD, and TEM . The results show that both high calcination temperature and high amount of Co loading result in relatively large Co 3 O 4 particles. The reduced cobalt catalysts consist of three cobalt species, including metallic Co, cobalt oxides and cobalt species interacting with zeolite (cobalt aluminate/silicate), due to incomplete reduction of cobalt species. The absence of the characteristic peak of metallic Co in the XRD pattern confirms its high dispersion on NaY, in agreement with the TEM results. H 2 -TPD effectively quantifies the number of surface metallic Co sites, which correlates linearly with the ethyl lactate conversion. This correlation indicates that metallic Co is the active site for ethyl lactate hydrogenation. A complete conversion of ethyl lactate with a selectivity of 96% to 1,2-PDO has been achieved over the 6Co/NaY-673-5 catalyst.
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
CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Yushan Li,Qingqing Xie,Mengyu Wang,Zhenyang Wang,Jiefeng Liu,Yiyao Du,Dongpei Zhang,Mengyuan Liu,Guangyu Zhang,Xin Jin,Chaohe Yang
Solketal is known as a promising non-BPA plasticizer . However, fast and robust synthesis of solketal from bio-oxygenates remains a grand challenge, as strong surface polarization often deactivates acidic catalysts. We proposed and validated a dual designing strategy, involving (1) Fe 3+ modified Bronsted acidity and (2) chlorotrimethylsilane (CTS) altered hydrophilicity for enhanced activity and stability of NaY catalysts. As one of the key findings, Fe 3+ exchanged NaYs display an unusual shortened Si-OH bond and electronically reconfigured Fe 3+ sites for a 4-fold activity enhancement. Furthermore, CTS modified FeY materials further alleviate surface passivation of glycerol and water, leading to an 18-fold activity improvement and better durability for acetalization of glycerol. CTS modified FeY catalysts display remarkable stability against varies impurity molecules. The dual modification methodology provides useful information on rational design of durable catalysts for synthesis of various other non-BPA derivatives.
研究领域:
催化化学
·
绿色化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
CHINESE JOURNAL OF CATALYSIS
·
2024
·
IF 15.7
Ke Huang,Shicheng Yuan,Rongyan Mei,Ge Yang,Peng Bai,Hailing Guo,Chunzheng Wang,Svetlana Mintova
A chlorine-free catalyst consisting of zeolite Y modified with Pd (Pd/NaY) catalyst has been prepared and used in the indirect oxidative carbonylation of methanol to dimethyl carbonate (DMC). The activity and stability of the catalyst were further improved by introducing molybdenum into Pd/NaY using a top-down approach (Pd-Mo/NaY catalyst). The Pd-Mo/NaY catalyst exhibited higher stability compared to the Pd/NaY. A high CO conversion of 97% and DMC selectivity of 80% during a 30-hour catalytic test for the Pd-Mo/NaY were obtained. Furthermore, the incorporation of Mo was found to partially heal the silanols and hinder the aggregation of Pd in the Pd-Mo/NaY catalyst. The interactions between Mo and Pd increased the amount of active Pd 2+ species and enhanced the adsorption of CO reactant on the Pd-Mo/NaY catalyst. The key reaction intermediate of COOCH 3 * was captured by in situ diffuse reflectance infrared Fourier transform spectroscopy . The stabilization of active Pd 2+ species contributed to the enhanced catalytic activity of the Pd-Mo/NaY catalyst in the indirect oxidative carbonylation of methanol to DMC reaction.
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
Journal of Environmental Chemical Engineering
·
2022
·
IF 7.968
Shixiong Tang,Fang Li,Jidong Liu,Bao Guo,Zenan Tian,Jianhua Lv
The treatment and reuse of polyester wastes have received widespread attention. In this work, MgO/NaY catalysts with different MgO contents were prepared by the incipient-wetness impregnation method and used in the methanolysis of PET for the first time, proposing a convenient and feasible method to solve the plastic recycling crisis. To characterize the surface and structural properties of the prepared MgO/NaY catalysts by EDXRF, BET, XRD, SEM, FT-IR and TEM. The acid-base properties of the catalysts were also characterized by CO 2 -TPD and NH 3 -TPD. The relationship between acid-base and catalytic activity showed that the conversion of PET and the yield of DMT increased with the increase of alkalinity of the catalyst. The results showed that the PET conversion and the DMT yield could reach 99% and 91%, respectively, under the reaction conditions of 200 °C, 30 min, catalyst dosage of 4 wt%, and the mass ratio of methanol to PET of 6 with 21%MgO/NaY as the catalyst. The recyclability of the catalyst was investigated, and the 21%MgO/NaY catalyst still had excellent catalytic activity for the methanolysis of PET after 6 cycles.
研究领域:
材料科学
·
环境科学
·
化学工程
✓ 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）