Surfactant recovery from mesoporous metal-modified materials (Sn–, Y–, Ce–, Si–MCM-41), by ultrasound assisted ion-exchange extraction and its re-use for a microwave in situ cheap and eco-friendly MCM-41 synthesis

2014 ◽  
Vol 2 (19) ◽  
pp. 7020-7033 ◽  
Author(s):  
J. González-Rivera ◽  
J. Tovar-Rodríguez ◽  
E. Bramanti ◽  
C. Duce ◽  
I. Longo ◽  
...  
Keyword(s):  
Low Temperature ◽  
Ion Exchange ◽  
Ultrasound Assisted ◽  
Exchange Extraction ◽  
Mesoporous Metal ◽  
Mcm 41 ◽  
Surfactant Recovery

Metal substituted (Y, Sn and Ce) MCM-41 materials were synthesized and detemplated by a low temperature methodology.

Facile in situ Encapsulation of Highly Dispersed Ni@MCM-41 for the Trans-Decalin Production from Hydrogenation of Naphthalene at Low Temperature

ChemCatChem ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 1286-1294 ◽  
Author(s):  
Xiaoyun Song ◽  
Qingxin Guan ◽  
Yu Shu ◽  
Xiaojing Zhang ◽  
Wei Li
Keyword(s):  
Low Temperature ◽  
Highly Dispersed ◽  
Mcm 41

Effective catalysts for the low-temperature NH3-SCR process based on MCM-41 modified with copper by template ion-exchange (TIE) method

2018 ◽  
Vol 237 ◽  
pp. 927-937 ◽  
Author(s):  
Andrzej Kowalczyk ◽  
Aneta Święs ◽  
Barbara Gil ◽  
Małgorzata Rutkowska ◽  
Zofia Piwowarska ◽  
...  
Keyword(s):  
Low Temperature ◽  
Ion Exchange ◽  
Nh3 Scr ◽  
Mcm 41

In situ ultrasound-assisted ion exchange synthesis of sphere-like AgClxBr1-x composites with enhanced photocatalytic activity and stability

2020 ◽  
Vol 27 (35) ◽  
pp. 43615-43624
Author(s):  
Abulikemu Abulizi ◽  
Kuerbangnisha Kadeer ◽  
Hujiabudula Maimaitizi ◽  
Yalkunjan Tursun ◽  
Dilinuer Talifu
Keyword(s):  
Photocatalytic Activity ◽  
Ion Exchange ◽  
Ultrasound Assisted

scholarly journals Spherical Al-MCM-41 Doped with Copper by Modified TIE Method as Effective Catalyst for Low-Temperature NH3-SCR

Molecules ◽  
2021 ◽  
Vol 26 (6) ◽  
pp. 1807
Author(s):  
Aleksandra Jankowska ◽  
Andrzej Kowalczyk ◽  
Małgorzata Rutkowska ◽  
Marek Michalik ◽  
Lucjan Chmielarz
Keyword(s):  
Low Temperature ◽  
Ion Exchange ◽  
Ammonia Oxidation ◽  
Surface Acidity ◽  
Ammonia Solution ◽  
Exchange Method ◽  
Copper Species ◽  
Nh3 Scr ◽  
Side Process ◽  
Mcm 41

Aluminum containing silica spherical MCM-41 was synthesized and modified with copper by the template ion-exchange method (TIE) and its modified version, including treatment of the samples with ammonia solution directly after template ion-exchange (TIE-NH3). The obtained samples were characterized with respect to their chemical composition (ICP-OES), structure (XRD), texture (low temperature N2 sorption), morphology (SEM-EDS), form and aggregation of deposited copper species (UV-vis DRS), reducibility of copper species (H2-TPR), and surface acidity (NH3-TPD). The deposition of copper by the TIE-NH3 method resulted in much better dispersion of this metal on the MCM-41 surface comparing to copper introduced by TIE method. It was shown that such highly dispersed copper species, mainly monomeric Cu2+ cations, deposited on aluminum containing silica spheres of MCM-41, are significantly more catalytically effective in the NH3-SCR process than analogous catalysts containing aggregated copper oxide species. The catalysts obtained by the TIE-NH3 method effectively operated in much broader temperature and were less active in the side process of direct ammonia oxidation by oxygen.

Propene production at low temperature by bimetallic Ni-Mo and Ni-Re catalysts on mesoporous MCM-41 prepared using template ion exchange

Fuel ◽  
2021 ◽  
Vol 284 ◽  
pp. 119031
Author(s):  
L. Alvarado Perea ◽  
M. Felischak ◽  
T. Wolff ◽  
J.A. López Gaona ◽  
C. Hamel ◽  
...  
Keyword(s):  
Low Temperature ◽  
Ion Exchange ◽  
Mcm 41

Enhanced catalytic performance in low-temperature NH3-SCR process of spherical MCM-41 modified with Cu by template ion-exchange and ammonia treatment

2021 ◽  
Vol 315 ◽  
pp. 110920
Author(s):  
Aleksandra Jankowska ◽  
Agata Chłopek ◽  
Andrzej Kowalczyk ◽  
Małgorzata Rutkowska ◽  
Włodzimierz Mozgawa ◽  
...  
Keyword(s):  
Low Temperature ◽  
Ion Exchange ◽  
Catalytic Performance ◽  
Ammonia Treatment ◽  
Nh3 Scr ◽  
Mcm 41

In situ Tensile Experiments at Low Temperatures on Niobium Single Crystals by H.V.E.M.

1975 ◽  
Vol 33 ◽  
pp. 58-59
Author(s):  
F. H. Louchet ◽  
L. P. Kubin
Keyword(s):  
Electron Microscope ◽  
Transition Temperature ◽  
Low Temperature ◽  
Slip System ◽  
Low Temperatures ◽  
Tensile Axis ◽  
Image Intensifier ◽  
Screw Dislocations ◽  
Source Operation

Experiments have been carried out on the 3 MeV electron microscope in Toulouse. The low temperature straining holder has been previously described Images given by an image intensifier are recorded on magnetic tape.The microtensile niobium samples are cut in a plane with the two operative slip directions [111] and lying in the foil plane. The tensile axis is near [011].Our results concern:- The transition temperature of niobium near 220 K: at this temperature and below an increasing difference appears between the mobilities of the screw and edge portions of dislocations loops. Source operation and interactions between screw dislocations of different slip system have been recorded.

Role of boundaries in the crystallization of amorphous films

1988 ◽  
Vol 46 ◽  
pp. 626-627
Author(s):  
D. A. Smith
Keyword(s):  
Low Temperature ◽  
Amorphous State ◽  
Nucleation And Growth ◽  
Amorphous Films ◽  
Island Nucleation ◽  
Surface Steps ◽  
Transmission Electron ◽  
Component Systems ◽  
Temperature Deposition

The nucleation and growth processes which lead to the formation of a thin film are particularly amenable to investigation by transmission electron microscopy either in situ or subsequent to deposition. In situ studies have enabled the observation of island nucleation and growth, together with addition of atoms to surface steps. This paper is concerned with post-deposition crystallization of amorphous alloys. It will be argued that the processes occurring during low temperature deposition of one component systems are related but the evidence is mainly indirect. Amorphous films result when the deposition conditions such as low temperature or the presence of impurities (intentional or unintentional) preclude the atomic mobility necessary for crystallization. Representative examples of this behavior are CVD silicon grown below about 670°C, metalloids, such as antimony deposited at room temperature, binary alloys or compounds such as Cu-Ag or Cr O2, respectively. Elemental metals are not stable in the amorphous state.

scholarly journals Insight into the Promoting Role of Er Modification on SO2 Resistance for NH3-SCR at Low Temperature over FeMn/TiO2 Catalysts

Catalysts ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 618
Author(s):  
Huan Du ◽  
Zhitao Han ◽  
Xitian Wu ◽  
Chenglong Li ◽  
Yu Gao ◽  
...  
Keyword(s):  
Low Temperature ◽  
Catalyst Surface ◽  
Impregnation Method ◽  
In Situ Drifts ◽  
Tio2 Catalyst ◽  
Nh3 Scr ◽  
Nh3 Adsorption ◽  
So2 Resistance ◽  
Fast Scr

Er-modified FeMn/TiO2 catalysts were prepared through the wet impregnation method, and their NH3-SCR activities were tested. The results showed that Er modification could obviously promote SO2 resistance of FeMn/TiO2 catalysts at a low temperature. The promoting effect and mechanism were explored in detail using various techniques, such as BET, XRD, H2-TPR, XPS, TG, and in-situ DRIFTS. The characterization results indicated that Er modification on FeMn/TiO2 catalysts could increase the Mn4+ concentration and surface chemisorbed labile oxygen ratio, which was favorable for NO oxidation to NO2, further accelerating low-temperature SCR activity through the “fast SCR” reaction. As fast SCR reaction could accelerate the consumption of adsorbed NH3 species, it would benefit to restrain the competitive adsorption of SO2 and limit the reaction between adsorbed SO2 and NH3 species. XPS results indicated that ammonium sulfates and Mn sulfates formed were found on Er-modified FeMn/TiO2 catalyst surface seemed much less than those on FeMn/TiO2 catalyst surface, suggested that Er modification was helpful for reducing the generation or deposition of sulfate salts on the catalyst surface. According to in-situ DRIFTS the results of, the presence of SO2 in feeding gas imposed a stronger impact on the NO adsorption than NH3 adsorption on Lewis acid sites of Er-modified FeMn/TiO2 catalysts, gradually making NH3-SCR reaction to proceed in E–R mechanism rather than L–H mechanism. DRIFTS.

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