Oligomerization of isobutene with a beta-zeolite membrane: Effect of the acid properties of the catalytic membrane

2011 ◽  
Vol 166 (1) ◽  
pp. 205-208 ◽  
Author(s):  
M. Torres ◽  
M. Gutiérrez ◽  
V. Mugica ◽  
M. Romero ◽  
L. López
Keyword(s):  
Zeolite Membrane ◽  
Beta Zeolite ◽  
Catalytic Membrane ◽  
Acid Properties ◽  
Membrane Effect

Template-free synthesis of beta zeolite membranes on porous α-Al2O3 supports

2014 ◽  
Vol 50 (64) ◽  
pp. 8834-8837 ◽  
Author(s):  
Yanting Tang ◽  
Xiufeng Liu ◽  
Shifeng Nai ◽  
Baoquan Zhang
Keyword(s):  
Seed Layer ◽  
Secondary Growth ◽  
Zeolite Membrane ◽  
Beta Zeolite ◽  
Zeolite Membranes ◽  
Organic Templates ◽  
Template Free ◽  
Α Al2o3

The preferentially (h0l)-oriented beta zeolite membrane was prepared on the porous α-Al2O3 support by secondary growth of a beta seed layer in the absence of organic templates.

The Investigation of Preparing the Beta Zeolite Membrane by the Way of Secondary Growth

2012 ◽  
Vol 608-609 ◽  
pp. 1463-1466 ◽  
Author(s):  
Guo Lin Shao ◽  
Chun Ling Yu ◽  
Ying Huan Fu ◽  
Hong Yi Dai ◽  
Li Ping Zhang
Keyword(s):  
Secondary Growth ◽  
Dip Coating ◽  
Zeolite Membrane ◽  
Beta Zeolite ◽  
Self Assembling ◽  
Large Pore ◽  
Coating Method ◽  
Support Tube ◽  
Dip Coating Method ◽  
The Way

Beta zeolite membrane was prepared on the surface of α-Al2O3support tube with large pore by the way of secondary growth. Different seeding techniques, such as ultrasonic surge, self-assembling and dip-coating, were investigated, and the results indicated that the best one was dip-coating method for the support with large pore. The prepared membrane was characterized by SEM and XRD. It was proved that the beta zeolite membrane prepared by the way of secondary growth is continuous, dense and defect-free.

Rapid, Non-Toxic Synthesis of Beta Zeolites

2018 ◽  
Author(s):  
Felix Hemmann ◽  
Jonathan Hackebeil ◽  
Andreas Lißner ◽  
Florian Mertens
Keyword(s):  
Hydrofluoric Acid ◽  
Molecular Sieves ◽  
Toxic Chemicals ◽  
Lewis Acidity ◽  
Beta Zeolite ◽  
Seeded Growth ◽  
Related Research ◽  
Beta Zeolites ◽  
Growth Method ◽  
Fast Synthesis

Molecular sieves with beta zeolite topology are promising catalysts for various reactions as they exhibits extraordinary Lewis acidity. However, their industrial application and related research in academica is hindered because their synthesis is time consuming and typically involves toxic chemicals as hydrofluoric acid. Therefore, tetraethylammonium fluorid was tested as a non-toxic fluotide source for the synthesis of beta zeolites. In combination with the previously reported nano-seeded growth method, a fast synthesis of beta zeolites only involving non-toxic chemicals was possible. Synthesized zeolites show comparable selectivity in the Bayer-Villinger oxidation as conventional zeolites synthesized with hydrofluoric acid.<br>

Model reactions for the study of hydrogenation and acidic activity of palladium catalysts

1987 ◽  
Vol 52 (8) ◽  
pp. 2019-2027 ◽  
Author(s):  
Libor Červený ◽  
Nguyen Thi Du ◽  
Ivo Paseka
Keyword(s):  
Palladium Catalysts ◽  
Styrene Oxide ◽  
Side Reactions ◽  
Pd Catalysts ◽  
Variable Parameters ◽  
Acid Properties ◽  
Liquid Phase Hydrogenation ◽  
Acid Catalysed Reactions ◽  
Different Content ◽  
Model Reactions

Palladium catalysts have been used to study the hydrogenation of 1-phenyl-2-butene-1-ol which is accompanied by several side reactions considered to be acid-catalysed. Another model reaction studied was dehydration and subsequent hydrogenation or hydrogenolysis of 1-phenyl-1,3-propanediol to 3-phenyl-1-propanol, accompanied by formation of propylbenzene. The dehydration and propylbenzene formation can be again classified as acid-catalysed reactions. Another one is methanolysis of styrene oxide taking place under conditions of liquid phase hydrogenation due to the acid properties of Pd-H systems. Hydrogenation activity of Pd catalysts was tested by hydrogenation of cyclohexene. Sixteen Pd catalysts on different supports and with different content of active component were used, their activity and selectivity was determined and the effect of variable parameters in the synthesis of these catalysts on the activity and selectivity is discussed.

Surface Proteins of the Erythrocyte Membrane Effect of Aging

Vox Sanguinis ◽  
1974 ◽  
Vol 26 (1) ◽  
pp. 1-13 ◽  
Author(s):  
Michael J. Conrad ◽  
John T. Penniston
Keyword(s):  
Erythrocyte Membrane ◽  
Surface Proteins ◽  
Membrane Effect

scholarly journals Influence of Chemical Osmosis on Solute Transport and Fluid Velocity in Clay Soils

2020 ◽  
Vol 18 (1) ◽  
pp. 232-238
Author(s):  
Zhihong Zhang ◽  
Gailei Tian ◽  
Lin Han
Keyword(s):  
Solute Transport ◽  
Transport Model ◽  
Fluid Velocity ◽  
Diffusion Mechanism ◽  
Clay Material ◽  
Chemical Osmosis ◽  
Advection Diffusion Equation ◽  
Test Study ◽  
Proposed Model ◽  
Membrane Effect

AbstractSolute transport through the clay liner is a significant process in many waste landfills or unmanaged landfills. At present, researchers mainly focus on the test study about semi-membrane property of clay material, however, the influence of chemical osmosis caused by membrane effect on solute transport and fluid velocity is insufficient. In this investigation, based on the classical advection-diffusion equation, a one-dimensional solute transport model for low-permeable clay material has been proposed, in which the coupled fluid velocity related with hydraulic gradient and concentration gradient is introduced, and the semi-membrane effect is embodied in the diffusion mechanism. The influence of chemical osmosis on fluid velocity and solute transport has been analyzed using COMSOL Multiphysics software. The simulated results show that chemical osmosis has a significant retarded action on fluid velocity and pollutant transport. The proposed model can effectively reveal the change in process of coupled fluid velocity under dual gradient and solute transport, which can provide a theoretical guidance for similar fluid movement in engineering.

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