Synthesis and surface properties of Ti-containing mesoporous aluminophosphates. A comparison with Ti-grafted mesoporous silica Ti-MCM-41

2003 ◽  
Vol 349 ◽  
pp. 259-264 ◽  
Author(s):  
Enrica Gianotti ◽  
Erica C. Oliveira ◽  
Salvatore Coluccia ◽  
Heloise O. Pastore ◽  
Leonardo Marchese
2018 ◽  
Vol 5 (3) ◽  
pp. 172021 ◽  
Author(s):  
Rania E. Morsi ◽  
Rasha S. Mohamed

A series of ordered mesoporous silica such as MCM-41, SBA-3 and SBA-15, in addition to silica micro- (SM) and nano- (SN) mesoporous particles, were prepared. The preparation conditions were found to greatly influence the physical-surface properties including morphological structure, porosity, particle size, aggregate average size, surface area, pore size, pore volume and zeta potential of the prepared silica, while the chemical structure, predicted from FT-IR spectra, and the diffraction patterns, predicted from wide-angle X-ray diffraction spectra, were identical. Surface areas of approximately 1500, 1027, 600, 552 and 317 m 2  g −1 , pore volumes of 0.93, 0.56, 0.82, 0.72 and 0.5 cm 3  g −1 , radii of 2.48, 2.2, 5.66, 6.6 and 8.98 nm, average aggregate sizes of 56, 65.4, 220.9, 73, 61.1 and 261 nm and zeta potential values of −32.8, −46.1, −26.3, −31.4 and −25.9 mV were obtained for MCM-41, SBA-3, SBA-15, SN and SM, respectively. Methylene blue dye uptake capacity of the prepared silica types was investigated using the batch technique and, in addition, the most effective material was further studied by the column flow system. The kinetics and isotherms of the uptake process were studied. The morphological structure, surface area, pore radius and zeta potential values were the most correlated factors.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yige Guo ◽  
Bin Chen ◽  
Ying Zhao ◽  
Tianxue Yang

AbstractAntibiotics are emerging pollutants and increasingly present in aquaculture and industrial wastewater. Due to their impact on the environment and health, their removal has recently become a significant concern. In this investigation, we synthesized nano zero-valent iron-loaded magnetic mesoporous silica (Fe-MCM-41-A) via precipitation and applied the adsorption of oxytetracycline (OTC) from an aqueous solution. The effects of competing ions such as Na+, Ca2+ and Cu2+ on the adsorption process under different pH conditions were studied in depth to providing a theoretical basis for the application of nanomaterials. The characterization of the obtained material through transmission electron microscopy demonstrates that the adsorbent possesses hexagonal channels, which facilitate mass transfer during adsorption. The loaded zero-valent iron made the magnetic, and was thus separated under an applied magnetic field. The adsorption of OTC onto Fe-MCM-41-A is rapid and obeys the pseudo-second-order kinetic model, and the maximum adsorption capacity of OTC is 625.90 mg g−1. The reaction between OTC and Fe-MCM-41-A was inner complexation and was less affected by the Na+. The effect of Ca2+ on the adsorption was small under acidic and neutral conditions. However, the promotion effect of Ca2+ increased by the increase of pH. Cu2+ decreased the removal efficiencies continuously and the inhibitory effects decrease varied with the increase of pH. We propose that surface complexing, ion-exchange, cationic π-bonding, hydrogen bonding, and hydrophobicity are responsible for the adsorption of OTC onto Fe-MCM-41-A.


2011 ◽  
Vol 143 (1) ◽  
pp. 174-179 ◽  
Author(s):  
Marília R. Mello ◽  
Delphine Phanon ◽  
Gleiciani Q. Silveira ◽  
Philip L. Llewellyn ◽  
Célia M. Ronconi

RSC Advances ◽  
2015 ◽  
Vol 5 (8) ◽  
pp. 5494-5500 ◽  
Author(s):  
Xin Yu Ming Dong ◽  
Yan Yan Li ◽  
Feng Wei ◽  
Yu Zhou ◽  
Shi Lu Zhou ◽  
...  
Keyword(s):  

Menthol could be adsorbed in as-synthesized MCM-41 at 373 K, open stored in ambient for 30 days and released at 333 K.


2011 ◽  
Vol 397 (1-2) ◽  
pp. 22-26 ◽  
Author(s):  
Oscar A. Anunziata ◽  
Andrea R. Beltramone ◽  
Maria L. Martinez ◽  
Lisandro J. Giovanetti ◽  
Felix. G. Requejo ◽  
...  

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