scholarly journals Preparation of Micro-Porous Alumina Sheet Support for Ceramic Membrane by Extrusion

2007 ◽  
Vol 1 (4) ◽  
pp. 547-555 ◽  
Author(s):  
Khanthima HEMRA ◽  
Duangduen ATONG ◽  
Pavadee AUNGKAVATTANA
2011 ◽  
Vol 695 ◽  
pp. 549-552
Author(s):  
Khanthima Hemra ◽  
Pavadee Aungkavattana ◽  
Duangduen Atong

Ceramic membrane has been extensively studied for a half of century. The research of alumina membranes was improved a great deal, however, they have always been considered as an opportunity in commercial product. In this research, submicron alumina powders, AKP-30 were deposited on the porous alumina tube support containing approximately 40% porosity by dip coating. The effects of solid loading, dispersant, and binder system on colloidal process were evaluated. It was found that the thickness of membrane layer depend on the type of binders (latex binder, polyvinyl alcohol binder, and poly (ethylene oxide) polymer binder) and dipping time when the withdrawal speed was constant. The proper suspension of 30 wt.% AKP-30 alumina powder with 18.8 wt.% latex binder provided proper sintered membrane without cracking or delaminating. The porosity and average pore size of coating layer was about 29% and 0.06 μm, respectively at a sintering temperature of 1400°C for 2 hr. The membrane layer was likely to thicken with increasing dipping time. The thickness of membrane after sintering was about 30-40 μm at a few second of dipping time.


2021 ◽  
Vol 938 (1) ◽  
pp. 012019
Author(s):  
N N Korysheva ◽  
S A Titov ◽  
S V Shakhov ◽  
G S Tikhonov ◽  
I A Glotova ◽  
...  

Abstract During deep processing of whey using microfiltration, the loss of membrane efficiency can take place. In this work, an installation for microfiltration of milk whey has been developed. It includes pumps, containers with liquids, throttling valves, a pressure gauge, and a microfiltration cell with a tubular ceramic membrane. A thin titanium oxide layer was deposited on the inner surface of the porous alumina tube. The outer diameter of the tubes is 10 mm, the wall thickness is 2 mm, the length of the tubes is 45 cm. A homogenized aqueous dispersion of sugar beet fiber was used as an agent that improves the performance of the installation by creating a pulsed backpressure of the filtrate. It is shown that the use of a finely ground suspension of dietary fiber during microfiltration of milk whey through a tubular ceramic membrane prevents the formation of protein deposits on the membrane and in its pores. The installation allows obtaining a suspension of dietary fiber, enriched with milk protein, as an additional product. The protein-enriched fiber suspension left over after microfiltration can be used in food production, for example, as a thickening agent in the production of yogurts.


2019 ◽  
Vol 45 (14) ◽  
pp. 17946-17954 ◽  
Author(s):  
Juan Ma ◽  
Xiuan Xi ◽  
Chao He ◽  
Weiwei Chen ◽  
Wei Tian ◽  
...  

2020 ◽  
Vol 22 (7) ◽  
pp. 1901442
Author(s):  
Juan Ma ◽  
Bin Du ◽  
Chao He ◽  
Shenghui Zeng ◽  
Kaihui Hua ◽  
...  

Membranes ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 872
Author(s):  
Jianzhou Du ◽  
Duomei Ai ◽  
Xin Xiao ◽  
Jiming Song ◽  
Yunping Li ◽  
...  

Air bearing has been widely applied in ultra-precision machine tools, aerospace and other fields. The restrictor of the porous material is the key component in air bearings, but its performance is limited by the machining accuracy. A combination of optimization design and material modification of the porous alumina ceramic membrane is proposed to improve performance within an air bearing. Porous alumina ceramics were prepared by adding a pore-forming agent and performing solid-phase sintering at 1600 °C for 3 h, using 95-Al2O3 as raw material and polystyrene microspheres with different particle sizes as the pore-forming agent. With 20 wt.% of PS50, the optimum porous alumina ceramic membranes achieved a density of 3.2 g/cm3, a porosity of 11.8% and a bending strength of 150.4 MPa. Then, the sintered samples were processed into restrictors with a diameter of 40 mm and a thickness of 5 mm. After the restrictors were bonded to aluminum shells for the air bearing, both experimental and simulation work was carried out to verify the designed air bearing. Simulation results showed that the load capacity increased from 94 N to 523 N when the porosity increased from 5% to 25% at a fixed gas supply pressure of 0.5 MPa and a fixed gas film thickness of 25 μm. When the gas film thickness and porosity were fixed at 100 μm and 11.8%, respectively, the load capacity increased from 8.6 N to 40.8 N with the gas supply pressure having been increased from 0.1 MPa to 0.5 MPa. Both experimental and simulation results successfully demonstrated the stability and effectiveness of the proposed method. The porosity is an important factor for improving the performance of an air bearing, and it can be optimized to enhance the bearing’s stability and load capacity.


Author(s):  
C.E. Voegele-Kliewer ◽  
A.D. McMaster ◽  
G.W. Dirks

Materials other than polymers, e.g. ceramic silicates, are currently being investigated for gas separation processes. The permeation characteristics of one such material, Vycor (Corning Glass #1370), have been reported for the separation of hydrogen from hydrogen iodide. This paper will describe the electron microscopy techniques applied to reveal the porous microstructure of a Vycor membrane. The application of these techniques has led to an increased understanding in the relationship between the substructure and the gas transport properties of this material.


2017 ◽  
Vol 32 (7) ◽  
pp. 731 ◽  
Author(s):  
XIE Yu-Zhou ◽  
PENG Chao-Qun ◽  
WANG Xiao-Feng ◽  
WANG Ri-Chu ◽  
LUO Feng

2015 ◽  
Vol 14 (9) ◽  
pp. 2139-2148 ◽  
Author(s):  
Sourja Ghosh ◽  
Priyankari Bhattacharya ◽  
Swachchha Majumdar ◽  
Somendra Nath Roy ◽  
Sibdas Bandyopadhyay

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