Nanostructured silica materials in olefin polymerisation: From catalytic behaviour to polymer characteristics

2012 ◽  
Vol 37 (12) ◽  
pp. 1764-1804 ◽  
Author(s):  
João M. Campos ◽  
João Paulo Lourenço ◽  
Henri Cramail ◽  
M. Rosário Ribeiro
2008 ◽  
Vol 8 (11) ◽  
pp. 5993-6002 ◽  
Author(s):  
R. Roque-Malherbe ◽  
F. Marquez-Linares ◽  
W. Del Valle ◽  
M. Thommes

Our focus in the present study is to apply high specific surface area silica nanostructured porous materials (about 2,200 m2/g, as synthesized, and 600–700 m2/g, after stabilization) to adsorb ammonia (NH3) for hydrogen storage and other chemical and pollution abatement applications. We describe here the synthesis, and characterization of these silica materials, and the adsorption study of N2 and NH3. These materials were obtained with the help of a modification of the Stöber-Fink-Bohn (SFB) method. The main change, made here to the SFB method, was the use of amines, i.e., triethylamine as catalysts instead of ammonium hydroxide. The silica materials have been characterized with the help of SEM and FTIR Spectrometry. The N2 adsorption study was carried out with the help of the Quantachrome-Autosorb-1 and the NH3 adsorption with the Quantachrome-Autosorb-1-C. The amount of hydrogen adsorbed in the form of NH3 in the studied silica samples at: P = 760 [Torr] (1.01325×105 [Pa]), was 2 [wt.%] and the amount of hydrogen stored in the form of NH3 at about: P = 7500 [Torr] (10.0×105 [Pa]), in the studied stabilized silica samples was 11 wt.%, a magnitude higher than the goal figure of 6.5 [wt.%] established by the United States of America, Department of Energy.


Langmuir ◽  
2013 ◽  
Vol 29 (6) ◽  
pp. 2007-2023 ◽  
Author(s):  
Julien Schmitt ◽  
Marianne Impéror-Clerc ◽  
Florentin Michaux ◽  
Jean-Luc Blin ◽  
Marie-José Stébé ◽  
...  

2011 ◽  
Vol 115 (11) ◽  
pp. 4616-4623 ◽  
Author(s):  
Ana R. Brás ◽  
Esther G. Merino ◽  
Paulo D. Neves ◽  
Isabel M. Fonseca ◽  
Madalena Dionísio ◽  
...  

2012 ◽  
Vol 1371 ◽  
Author(s):  
A. Mendoza-Nieto ◽  
I. Puente-Lee ◽  
C. Salcedo-Luna ◽  
T. Klimova

ABSTRACTIn the present work, a comparison study of the NiMo hydrodesulfurization (HDS) catalysts supported on different nanostructured supports of MCM-41 and SBA-15-types and the same ones modified by TiO2 grafting was undertaken. The aim of this study was to inquire on the effect of the characteristics of the primary silica supports on the activity and selectivity of the NiMo catalysts modified with titania in deep HDS. Supports and catalysts were characterized by nitrogen physisorption, small-angle and powder XRD, TPR, UV-vis DRS, and HRTEM, and tested in the simultaneous HDS of dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (4,6-DMDBT). It was found that titania grafting on all silica supports resulted in a slight decrease of BET surface area and total pore volume. However, the characteristic p6mm hexagonal pore arrangement of the used nanostructured silica materials was not affected. Powder X-ray diffraction pointed out a good dispersion of Mo and Ni oxide species in all prepared catalysts. TPR characterization of the NiMo catalysts revealed some increase in the metal-support interaction after titania grafting on the silica surface. Further DRS characterization indicated that the best dispersion of Mo oxide species was obtained on the TiSBA-15 support. Titania addition to the silica supports also produced an increase in the dispersion of the sulfided NiMo phase, which was more marked for SBA-15 support than for the MCM-41 (HRTEM). The most active NiMo/Ti-SBA-15 catalyst resulted to be significantly more active (∼40 %) than the conventional NiMo/γ-Al2O3 catalyst in HDS of 4,6-DMDBT.


Nano Letters ◽  
2009 ◽  
Vol 9 (8) ◽  
pp. 2877-2883 ◽  
Author(s):  
Timo Lebold ◽  
Christophe Jung ◽  
Jens Michaelis ◽  
Christoph Bräuchle

2014 ◽  
Vol 2 (37) ◽  
pp. 6283-6292 ◽  
Author(s):  
Ágnes Szegedi ◽  
Margarita Popova ◽  
Krassimira Yoncheva ◽  
Judit Makk ◽  
Judith Mihály ◽  
...  

Sulfadiazine-loaded silver nanoporous silica carriers have similar antibacterial properties as silver sulfadiazine.


2009 ◽  
Vol 2 (3) ◽  
pp. 99-106 ◽  
Author(s):  
Eugenia Fagadar-Cosma ◽  
Corina Enache ◽  
Dana Vlascici ◽  
Gheorghe Fagadar-Cosma ◽  
Hartmut Stadler ◽  
...  

2021 ◽  
Vol 138 ◽  
pp. 111222
Author(s):  
Violeta Purcar ◽  
Valentin Rădiţoiu ◽  
Alina Rădiţoiu ◽  
Florentina Monica Raduly ◽  
Raluca Manea ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document