CATALYTIC SURFACE MODIFICATION OF ALUMINA MEMBRANE FOR OXYGEN SEPARATION

Two types of alumina ceramic membrane in hollow fibre shape was used in this study. Both alumina hollow fibres (AHF) were sintered at different temperatures; (a) 1350oC and (b) 1450oC. In order to improve the catalytic activity of the alumina membrane for oxygen separation purposes, surface modification of the membranes was carried out using La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF) perovskite catalyst. LSCF was synthesised using simple Pechini sol-gel method. The evaporation time and temperature of the LSCF-sol were varied to obtain various viscosity of catalytic sol. From XRD analysis, pure LSCF perovskite structure formed at temperature at 850oC. The morphological of unmodified and surface-modified alumina hollow fibre membranes (AHF) were studied using FESEM. The effect of LSCF catalytic sol viscosity was studied and it was found that as the viscosity of the sol increases, the amount of catalyst deposited on the alumina hollow fibre were increased. Besides, the amount of catalyst deposited on 1350 AHF was found to be higher than 1450 AHF. This result is supported by the result of pore distribution data whereby 1350 AHF was observed to be more porous than 1450 AHF, with porosity percentage of 40.38% and 28.80%, respectively. Although higher viscosity of catalytic sol could lead to a high amount of catalyst deposited on the AHF substrate, there is a tendency for micro-cracks to develop. Thus, the viscosity of the catalytic sol is important to control in order to have higher oxygen permeation flux.

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Surface Modification of SiC Powder for Use in Electrophoretic Deposition

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.412.287 ◽

2009 ◽

Vol 412 ◽

pp. 287-290 ◽

Cited By ~ 3

Author(s):

Saki Sakakibara ◽

Tohru Suzuki ◽

Atsunori Matsuda ◽

Tetsuo Uchikoshi

Keyword(s):

Surface Modification ◽

Isoelectric Point ◽

Electrophoretic Deposition ◽

Hot Pressing ◽

Sol Gel ◽

Argon Atmosphere ◽

Green Compact ◽

Gel Method ◽

Sol Gel Method ◽

Surface Modified

The surface modification of SiC powder with an alumina precursor was achieved by a sol-gel method to apply the electrophoretic deposition (EPD) technique to the shaping of the SiC powder. The isoelectric point of the surface-modified SiC powder with sol-gel-derived alumina precursor was shifted to around pH 9, which is close to that of alumina. The alumina-coated SiC deposited on a cathodic substrate by EPD. The green compact of surface-modified SiC powder was sintered by hot pressing in an argon atmosphere at 2000oC.

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Preparation and applications of wettability-controlled fluoroalkyl end-capped oligomer/cellulose nanofiber composites

Journal of Composite Materials ◽

10.1177/0021998320951602 ◽

2020 ◽

pp. 002199832095160

Author(s):

Hideo Sawada ◽

Yui Endo ◽

Yuri Oikawa

Keyword(s):

Surface Modification ◽

Sol Gel ◽

Composite Films ◽

Cellulose Nanofiber ◽

Composite Surface ◽

Pet Fabric ◽

Methanol Solutions ◽

Poly Ethylene ◽

Surface Modified ◽

Fabric Surface

Sol-gel reaction of two fluoroalkyl end-capped vinyltrimethoxysilane oligomer [RF-(CH2CHSi(OMe)3) n-RF; RF = CF(CF3)OC3F7; n = 2, 3: RF-(VM) n-RF] in the presence of cellulose nanofiber (CNF) under non-catalytic conditions was found to provide the corresponding fluorinated oligomeric silica/CNF composites [RF-(VM-SiO3/2) n-RF/CNF]. The obtained composites were applied to the surface modification of glass to give a good oleophobic/superhydrophobic characteristic on the composite surface due to the fabrication of the roughness architecture. The RF-(VM-SiO3/2) n-RF/CNF composites were also applied to the surface modification of poly(ethylene terephthalate) [PET] fabric swatch, affording a superoleophilic/superhydrophobic characteristic on the modified fabric surface. Modified PET fabric swatch thus obtained was applicable to not only the separation membrane to separate the mixture of oil/water but also the perfect adsorption of oil droplets spread on water interface. In addition, we have prepared the RF-(VM-SiO3/2) n-RF/CNF composites films by casting homogeneous aqueous methanol solutions containing the corresponding composites. Pristine CNF film afforded the superoleophilic property on the surface; however, it was demonstrated that the obtained transparent colorless CNF composite films can supply highly oleophobic characteristic on the surface.

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Thin Film of Palladium on Alumina Ceramic Membrane Tube: Effect of Combine Sol-Gel Process with Electroless Plating on Deposits Morphology

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.447-448.700 ◽

2010 ◽

Vol 447-448 ◽

pp. 700-704

Author(s):

Sari Ratna ◽

Zahira Yaakob ◽

Ismail Manal ◽

Wan Ramli Wan Daud

Keyword(s):

Electroless Plating ◽

Ceramic Membrane ◽

Sol Gel ◽

Composite Membranes ◽

Alumina Ceramic ◽

Hydrogen Yield ◽

Alumina Membrane ◽

High Hydrogen ◽

Sol Gel Process ◽

Hydrogen Selectivity

In this work, the potential of utilizing the porous alumina ceramic membrane coated with palladium as a hydrogen permselective membrane has been studied. The ceramic membrane is characterized by high permeability but at low hydrogen selectivity. In order to increase the pure hydrogen selectivity and to obtain high hydrogen yield on the ceramic membrane, palladium was coated on the alumina membrane surface. Such an arrangement would also enable the ceramic membrane to be operated at higher temperature. The preparation of the palladium coated ceramic membrane was carried out using combine sol-gel process and the electroless plating technique. The effect of combine sol-gel process with electroless plating towards deposits morphology, hydrogen permeability, and hydrogen permselectivity were analysed. The thickness and morphology of the α- Alumina and Pd composite membranes were analysed using a scanning electron microscopy (SEM) and atomic force microscopy (AFM).

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Novel silica sand hollow fibre ceramic membrane for oily wastewater treatment

Journal of Environmental Chemical Engineering ◽

10.1016/j.jece.2020.104975 ◽

2021 ◽

Vol 9 (1) ◽

pp. 104975

Author(s):

Saber Abdulhamid Alftessi ◽

Mohd. Hafiz Dzarfan Othman ◽

Mohd. Ridhwan Adam ◽

Twibi Mohamed Farag ◽

Ahmad Fauzi Ismail ◽

...

Keyword(s):

Wastewater Treatment ◽

Ceramic Membrane ◽

Hollow Fibre ◽

Silica Sand ◽

Oily Wastewater ◽

Oily Wastewater Treatment

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Synthesis and characterization of superoleophobic fumed alumina nanocomposite coated via the sol-gel process onto ceramic-based hollow fibre membrane for oil-water separation

Ceramics International ◽

10.1016/j.ceramint.2021.05.319 ◽

2021 ◽

Author(s):

Yusuf Olabode Raji ◽

Mohd Hafiz Dzarfan Othman ◽

Nik Abdul Hadi Sapiaa Md Nordin ◽

Mohd Ridhwan Adam ◽

Khairul Anwar Mohd Said ◽

...

Keyword(s):

Sol Gel ◽

Hollow Fibre ◽

Synthesis And Characterization ◽

Water Separation ◽

Hollow Fibre Membrane ◽

Fibre Membrane ◽

Sol Gel Process ◽

Oil Water Separation ◽

Oil Water

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Aqueous Sol-Gel Synthesis of Different Iron Ferrites: From 3D to 2D

Materials ◽

10.3390/ma14061554 ◽

2021 ◽

Vol 14 (6) ◽

pp. 1554

Author(s):

Justinas Januskevicius ◽

Zivile Stankeviciute ◽

Dalis Baltrunas ◽

Kęstutis Mažeika ◽

Aldona Beganskiene ◽

...

Keyword(s):

Magnetic Measurements ◽

Substrate Surface ◽

Sol Gel ◽

Synthesis Method ◽

Xrd Analysis ◽

Dip Coating ◽

Yttrium Iron ◽

Iron Garnet ◽

Dip Coating Technique ◽

Sol Gel Synthesis

In this study, an aqueous sol-gel synthesis method and subsequent dip-coating technique were applied for the preparation of yttrium iron garnet (YIG), yttrium iron perovskite (YIP), and terbium iron perovskite (TIP) bulk and thin films. The monophasic highly crystalline different iron ferrite powders have been synthesized using this simple aqueous sol-gel process displaying the suitability of the method. In the next step, the same sol-gel solution was used for the fabrication of coatings on monocrystalline silicon (100) using a dip-coating procedure. This resulted, likely due to substrate surface influence, in all coatings having mixed phases of both garnet and perovskite. Thermogravimetric (TG) analysis of the precursor gels was carried out. All the samples were investigated by X-ray powder diffraction (XRD) analysis. The coatings were also investigated by scanning electron microscopy (SEM), atomic force microscopy (AFM) and Mössbauer spectroscopy. Magnetic measurements were also carried out.

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Hard Coating Materials Based on Photo-Reactive Silsesquioxane for Flexible Application: Improvement of Flexible and Hardness Properties by High Molecular Weight

Polymers ◽

10.3390/polym13101564 ◽

2021 ◽

Vol 13 (10) ◽

pp. 1564

Author(s):

Jong Tae Leem ◽

Woong Cheol Seok ◽

Ji Beom Yoo ◽

Sangkug Lee ◽

Ho Jun Song

Keyword(s):

Molecular Weight ◽

Surface Morphology ◽

High Molecular Weight ◽

Sol Gel ◽

Xrd Analysis ◽

Polyhedral Oligomeric Silsesquioxanes ◽

Coating Materials ◽

Pencil Hardness ◽

Coated Film ◽

Flexible Application

EPOSS of polyhedral oligomeric silsesquioxanes (POSS) mixture structure and LPSQ of ladder-like polysilsesquioxane (LPSQ) structure were synthesized via sol–gel reaction. EPSQ had a high molecular weight due to polycondensation by potassium carbonate. The EPSQ film showed uniform surface morphology due to regular double-stranded structure. In contrast, the EPOSS-coated film showed nonuniform surface morphology due to strong aggregation. Due to the aggregation, the EPOSS film had shorter d-spacing (d1) than the EPSQ film in XRD analysis. In pencil hardness and nanoindentation analysis, EPSQ film showed higher hardness than the EPOSS film due to regular double-stranded structure. In addition, in the in-folding (r = 0.5 mm) and out-folding (r = 5 mm) tests, the EPSQ film did not crack unlike the EPOSS coated film.

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