NANO
·
2024
·
IF 1
Xuecong Ma,Linlin Geng,Yu Li,Jianwen Wei,Lei Liao,Dunqiu Wang
Micro/mesoporous materials are low-cost functional materials with the potential for CO 2 adsorption. Modifying micro/mesoporous materials is significant for enhancing CO 2 adsorption and their high-value utilization. Herein, the micro/mesoporous material of composite molecular sieve ZSM-5/MCM-48 (ZM) was synthesized by a two-step crystallization method using cetyltrimethylammonium bromide as a template, tetraethyl orthosilicate as a silicon source and ZSM-5 seed as part of silicon aluminum source. Tetraethylenepentamine (TEPA) and polyethyleneimine (PEI) were used as impregnation modifiers to modify ZM with amine groups. The results showed that with the increase of amine loadings, both ZM-T60 (Impregnated with TEPA) and ZM-P60 (Impregnated with PEI) functionalized adsorbents exhibited the best adsorption capacities of 4 . 9 7 mmol ⋅ g − 1 and 3 . 2 8 mmol ⋅ g − 1 at 60, respectively, when the loading of ZM sample was 60%. The adsorption kinetic analysis showed that the adsorption of CO 2 by ZM-T60 and ZM-P60 was a chemisorption-dominated process accompanied by physical adsorption. After 10 adsorption/desorption cycles, the CO 2 adsorption capacity of ZM-T60 and ZM-P60 decreased by 8.7% and 2.6%, respectively. This work demonstrates that impregnation modification of the composite molecular sieve to achieve efficient CO 2 adsorption has practical application significance.
研究领域:
材料科学
·
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
APPLIED CATALYSIS A-GENERAL
·
2016
·
IF 4.012
Alberto Romero,Antonio Nieto-Márquez,Esther Alonso
Three different bimetallic Ru:Ni catalysts supported on a mesoporous silica MCM-48 were prepared by consecutive wet impregnations, with a total metal loading of ca. 3% (w w −1 ). Ru:Ni ratios spanned in the range of 0.15–1.39 (w w −1 ) and were compared with the corresponding monometallic Ni/MCM-48. The catalysts so prepared were characterized by X-Ray Diffraction, Transmission Electron Microscopy, adsorption/desorption of N 2 , Temperature Programmed Reduction, NH 3 − TPD and Atomic Absorption, and tested in the liquid phase hydrogenation of d -glucose into sorbitol in the temperature range 120–140 °C under 2.5 MPa of H 2 pressure. Bimetallic catalysts with Ru:Ni ratios higher than 0.45 enhanced the catalytic behavior of the monometallic Ni/MCM-48 in the reaction, increasing the reaction rate and showing complete selectivity to sorbitol by minimizing the production of mannitol. Ru:Ni/MCM-48 (0.45) was recovered from the reaction media and tested for three reaction cycles, showing good stability under the selected experimental conditions.
研究领域:
催化化学
·
材料科学
✓ 已验证
DOI
高影响因子
CHEMOSPHERE
·
2018
·
IF 4.427
Xukai Li,Weirui Chen,Yiming Tang,Laisheng Li
Fe-MCM-48 catalyst with a three-dimensional cubic pore structure was directly synthesized via a hydrothermal method, and the mineralization efficiency of diclofenac (DCF) in the catalytic ozonation process (Fe-MCM-48/O 3 ) was assessed. X-ray diffraction (XRD), N 2 adsorption desorption, transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) characterizations revealed that Fe existed in the framework of MCM-48, and Fe-MCM-48 possessed a large surface area and a highly ordered cubic mesoporous structure, which could accelerate reactants and products diffusion. Regarding mineralization efficiency, the addition of Fe-MCM-48 significantly improved total organic carbon (TOC) removal, and approximately 49.9% TOC were removed through the Fe-MCM-48/O 3 process at 60 min, which was 2.0 times higher than that in single ozonation. Due to this catalyst's superior structure, Fe-MCM-48 showed the better catalytic activity compared with Fe-MCM-41 and Fe loaded MCM-48 (Fe/MCM-48, Fe existed on the surface of MCM-48). DCF removal in the Fe-MCM-48/O 3 process was primarily based on ozone direct oxidation. The improvement of mineralization efficiency was attributed to the function of generated hydroxyl radicals (•OH), which indicated that the presence of Fe-MCM-48 accelerated ozone decomposition . Moreover, the negatively charged surface of Fe-MCM-48 and the proper pH value of the DCF solution played an essential role in OH generation.
研究领域:
环境科学
·
催化材料
✓ 已验证
DOI
高影响因子
DESALINATION
·
2016
·
IF 4.412
Lu Liu,Guiru Zhu,Zhaofeng Liu,Congjie Gao
Monodispersed spherical MCM-48 nanoparticles with three-dimensional cubic mesostructure were synthesized and used as nanofillers dispersed in the aqueous or organic phase to prepare thin film nanocomposite (TFN) membranes through the interfacial polymerization of m -phenylenediamine and trimesoyl chloride. Scanning and transmission electron microscope images of the isolated polyamide (PA) active layer confirm that MCM-48 nanoparticles were embedded throughout the PA layer with dispersion in the organic phase as they were clipped between the PA layer and the polysulfone support with dispersion in the aqueous phase . Water flux was measured at 16 bar with 2000 ppm NaCl solution. Furthermore, water flux increased gradually from 24 L/m 2 ·h to 40 L/m 2 ·h with the increase in MCM-48 content in the organic phase, without significantly affecting salt rejection (>95%). Water flux increased from 24 L/m 2 ·h to 68 L/m 2 ·h, whereas salt rejection decreased from 97% to 80% with the increase in MCM-48 content in the aqueous phase. Less MCM-48 can be used in the aqueous phase than in the organic phase with similar performances. The two kinds of TFN membranes exhibit enhanced long-term durability, which confirms that MCM-48 can stably reside in the TFN membranes by dispersing whether in the organic or aqueous phase.
研究领域:
材料科学
·
环境工程
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2019
·
IF 3.375
Xingchi Qian,Junhao Yang,Zhaoyang Fei,Qing Liu,Zhuxiu Zhang,Xian Chen,Jihai Tang,Mifen Cui,Xu Qiao
Polyethylenimine (PEI) impregnated MCM-48 samples without calcination (MCM-48-W) whose pores are covered with cetyltrimethylammonium bromide (CTAB with long-alkyl chains) were verified to be more efficient CO2 adsorbents than PEI impregnated conventional MCM-48 samples. The samples were characterized by thermogravimetric analysis (TGA), X-ray powder diffraction (XRD), nitrogen adsorption–desorption, and Fourier transform infrared spectroscopy (FTIR) analysis. Also, CO2 adsorption behaviors including adsorption capacity, adsorption thermodynamics, and adsorbent stability were studied to reveal the CO2 adsorption performance on as-synthesized PEI supported materials. The experimental results indicated that the CO2 adsorption and amine efficiency of MCM-48-W were always higher than those of conventional MCM-48 samples at the same PEI loading. MCM-48-W impregnated with 40 wt % PEI (MCM-48-W(40)) exhibited 2.59 mmol·g–1 of CO2 adsorption capacity (6.9 mmol CO2/g PEI), the highest amine efficiency ever reported for MCM-48 impregnated PEI in pure CO2, which may be because the existence of long-alkyl chains improved the dispersion of PEI loading. We presented a simple strategy with the advantages of less consumption of PEI and omission of the calcination step for the improvement of PEI dispersion on MCM-48 with long-alkyl chains template for high efficiency CO2 adsorption.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2020
·
IF 16.683
Shangyi Li,Jun Huang,Zhuoxing Ye,Yaozhong Wang,Xukai Li,Jing Wang,Laisheng Li
In the peroxone process (O 3 /H 2 O 2 ), OH yield ratio with respect to O 3 consumption was low due to the competition experiments. Singular effectiveness of Co Ce as a supporting ligand in the interface of ozone-H 2 O 2 -catalysts and related complexes formed on catalysts enhanced the electron transfer between ozone chain reaction and various chemical state of Ce/Co. A computationally determined stereochemical structure corroborated that the Co Ce synergistic effect led to the region around Co atom (electron donor) with low Gibbs free energy to form OH. Meanwhile, reactive oxygen species (ROSs) were tend to attack the sites with very negative natural population charge or high frontier electron density (FED) values of sulfamethazine (SMT) by LC–MS/MS and density functional theory (DFT) calculations. Benefiting from the unique superoxide complexes and synergetic effect of Co Ce, the Co10Ce10@MCM-48 catalysts showed superior performance of SMT mineralization (64.1 %, 120 min), which resolved the low-efficient ROSs generation in bare peroxone reaction.
研究领域:
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2012
·
IF 2.103
Zhen Wang,Xinbo Ci,Hongjun Dai,Lu Yin,Huixiang Shi
A highly photoactive Ti-containing Cr-modified MCM-48 photocatalyst (Si/Ti = 3.4, Si/Cr = 50) was prepared by a facile one-step method at room temperature. A combination of various physicochemical techniques such as X-ray diffraction (XRD), N 2 physisorption, diffuse reflectance UV–vis spectra (DRS) and X-ray photoelectron spectra (XPS) were used to characterize the properties of the synthetic catalysts. The characterization and experimental results indicated that tetrahedral Ti oxide moieties as dominant Ti oxide were loaded into the mesoporous structure and there was a synergistic interaction between the Ti species anchored on the walls and the Cr ions presented in the MCM-48 framework, which was considered to be directly correlated to the photoactivity. The Ti-Cr-MCM-48 sample can remove H 2 S with the efficiency of 92% under visible light, being the Cr 6+ species primarily responsible for this photoactivity. A deactivation was observed as a consequence of sulfate accumulation on the surface of the catalyst and reduction of Cr 6+ .
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2015
·Vol. 39
·期 6
·4519-4525
·
IF 3.086
Yansheng Liu,Xinlin Li,Xuanduong Le,Wei Zhang,Hao Gu,Ruiwen Xue,Jiantai Ma
MCM-48 mesoporous microspheres (M48N) with a pore size of 3.77 nm, an ultra-high surface area of 1250.77 m2 g−1 and a super-large pore volume of 1.52 cm3 g−1 were synthesized. The M48N microspheres were then modified with Pd, Pt and Ru nanoparticles using an incipient wetness impregnation technique. The modified M48N microspheres were investigated to determine their catalytic effect in the aqueous phase hydro-dechlorination (HDC) of 4-chlorophenol. The Pd–M48N, Pt–M48N and Ru–M48N catalysts were characterized by transmission electron microscopy, X-ray diffraction, nitrogen adsorption–desorption and X-ray photoelectron spectroscopy. The HDC experiments were performed using the fairly mild conditions of room temperature and an atmospheric pressure of H2. Pd–M48N showed a higher catalytic performance than Pt–M48N and Ru–M48N and various other Pd-based catalysts. The high catalytic performance of Pd–M48N resulted from the ultra-high surface area, super-large pore volume and unique pore structure of the M48N, which improved the mass transfer and increased the rate of adsorption–desorption of the compounds. This method has potential applications in the treatment of industrial wastewaters contaminated with chlorinated organic compounds.
研究领域:
环境科学
·
催化化学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 10.652
Shangyi Li,Jun Huang,Xukai Li,Laisheng Li
Co-Ce as the dominant active sites immobilized MCM-48 (Co-Ce/MCM-48) was fabricated via H-bonding by the hydrothermal and incipient wetness co-impregnation method. The incorporation of Co-Ce/MCM-48 (67.2%) provided higher mineralization of sulfamethazine (SMT) than Co/MCM-48 (62.2%) and Ce/MCM-48 (39.4%) in O 3 /peroxymonosulfate (O 3 /PMS) system at 90 min reaction time. The catalytic efficiency could be further improved owing to enhanced PMS decomposition rate when initial pH increased to 9.4. The electron transfer capacity in Co-Ce/MCM-48/O 3 /PMS was improved according to in-situ electrochemical tests. In situ-Raman characterization implied that PMS was bonded to the Co⋯HO-Si-O-Si-OH⋯Ce to generate the Ce-OH⋯HSO 5 − and Co-OH⋯HSO 5 − complexes, which was decomposed by O 3 and one-electron transfer reaction into reactive oxygen species (ROSs). LC-MS analysis indicated that the breakage of N-S bond, SO 2 extrusion and -CH 3 oxidation on rings were the major degradation pathway during SMT degradation. To uncover the relationship of interface electron transfer with Co-Ce/MCM-48 and PMS activation by O 3 , electron paramagnetic resonance (EPR) spectra was recorded to investigate the variation of ROSs in different processes. Simultaneous PMS reduction and oxidation over the solid-liquid-gas interface occurred for the generation of free and non-free radicals in Co-Ce/MCM-48/O 3 /PMS process.
研究领域:
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2023
·
IF 8.6
Weirui Chen,Muxin Lin,Jiaxin Zhou,Xukai Li,Xipeng Wei,Gaozu Liao,Jing Wang,Laisheng Li
Lewis acid site was vital center for activating O 3 during catalytic ozonation process. Herein, we proposed a strategy to enhance the Lewis acid strength of Fe-MCM-48 (FeM) by fluorination. Fluorinated Fe-MCM-48 (FFeM) exhibited the better catalytic ozonation efficiency towards Ketoprofen (KET), a kind of nonsteroidal anti-inflammatory drug. 87.4 % TOC removal was obtained by F 2.5 Fe 0.8 M/O 3 process, but only 27.5 % and 52.7 % were found by sole ozonation and Fe 0.8 M/O 3 processes, respectively. Comparative characterizations, experiments and DFT calculations showed that fluorinated FFeM was regular sphere with three dimensional duct channel and large S BET . Doping of F reduced particle size, implanted electron withdrawing Si-F group and formed the electron poor center around Fe atom, which enhanced Lewis acid strength of FFeM. Protonated hydroxyl groups on Lewis acid sites were the main active sites for O 3 activation. Greater amount of O 3 were absorbed on the surface of FFeM and the greater O 3 utilization rate, •OH and •O 2 – generation rates were obtained by FFeM/O 3 process. Common anions such as Cl − , SO 4 2− and NO 3 – and Humic acids (HA) had little effect on KET removal but inhibited TOC removal in FFeM/O 3 process. •OH, •O 2 – and Fe(IV) = O oxidation were accounted for KET degradation. 16 kinds of intermediates generated from KET degradation and 4 pathways were deduced.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2015
·
IF 2.587
Z. B. Huang,B. S. Liu,X. H. Wang,X. Y. Tang,R. Amin
In order to improve the desulfurization efficiency of 50% MnxOy/MCM-48 sorbent, the preparation parameters including synthesis method (excessive impregnation, precipitation, and sol–gel), precursor selection (Mn(Ac)2 and Mn(NO3)2), heating rate during calcination (2°/min, 4°/min, 6°/min, and 8°/min), and calcination temperature (450 °C, 550 °C, 650 °C, and 750 °C) of sorbents were investigated systematically. The structure and composition of different sorbents were characterized by XRD, BET, TG/DSC, H2-TPR, UV–vis, TPSR, and FT-IR techniques. The results indicated that synthesis methods and precursors influenced remarkably the dispersion of active particles while the stable structure of MCM-48 and the dispersion of active particles correlated closely with the heating rate during calcination and calcination temperature of sorbents, which will influence the desulfurization efficiency of sorbents. Therefore, the better dispersion of active particles and integrity of MCM-48 structure will result in better desulfurization performance of sorbents. Thus, the best condition was the calcination temperature of 550 °C with a heating rate of 2°/min using Mn(Ac)2 as precursor by a sol–gel method.
研究领域:
环境化学
·
材料科学
·
化学工程
·
能源技术
✓ 已验证
DOI
高影响因子
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
·
2019
·Vol. 411
·期 13
·2817-2826
·
IF 3.286
Yu Hao,Jia Yuqian,Wu Ri,Chen Xiangfeng,Chan T.-W. Dominic
In this study, a magnetic molecular sieve material (Fe 3 O 4 @MCM-48) was synthesized by a combination of solvothermal and self-assembly methods. The physicochemical properties of the magnetic molecular sieve material were characterized by scanning electron microscopy, energy-dispersive spectroscopy, magnetic hysteresis loop measurements, transmission electron microscopy, powder X-ray diffraction, N 2 adsorption–desorption analysis, and Fourier transform infrared spectroscopy. The as-synthesized nanocomposite showed various advantages, including easy magnetic-assisted separation, high specific surface area, and a highly interwoven and branched mesoporous structure. The Fe 3 O 4 @MCM-48 nanocomposite was then used as an effective adsorbent material for magnetic solid-phase extraction of fluoroquinolones (FQs) from water samples. The FQs in the extract were determined via liquid chromatography–tandem mass spectrometry. Adsorption and desorption factors that affected the extraction performance were systematically optimized using spiked purified water samples. Good linearity (with R 2 > 0.99) was shown by this FQ detection system for FQ concentrations from 5 to 1000 ng L −1 . Moreover, low detection limits (0.7–6.0 ng L −1 ) and quantitation limits (2.5–20.0 ng L −1 ) and satisfactory repeatability (relative standard deviation < 10%, n = 6) were achieved for water samples. The developed method was also validated for the analysis of FQs in meat and milk samples. Finally, FQs in food and drinking water samples were successfully determined using the developed method.
Graphical abstract
研究领域:
分析化学
·
食品安全
·
环境科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）