Properties Of Ceramic Membranes Research Articles

THE EFFECT OF THE TYPE AND CONTENT OF CARBONATES ON THE CHARACTERISTICS OF POROSITY OF CERAMIC MEMBRANES

The main issue considered in the work is the creation of a matrix for ceramic membranes, which would be distinguished by low cost and high porosity. In order to reduce the cost of ceramic membranes, a widespread approach was chosen, which is powerfully used by many researchers, namely the use of natural minerals - kaolin and saponite - as the main components of the matrix. Carbonates were used as pore generating agents to achieve the required porosity value. Three series of ceramic membranes (CM) differing in chemical composition were synthesized in the work: KP1, KP2, and KP3 series. The main composition of CM includes: kaolin, saponite, sodium silicate and carbonates. The effect of the type and amount of carbonates (CaCO3, NH4HCO3, (NH4)2CO3) as pore generating agents on the formation of the porous structure of the samples was studied. The type and content of carbonates varied in different samples from 8 wt% up to 40 wt%. The dry pressing method using pressure equivalent to 8 tons and 15 tons was used to form ceramic membranes. The main parameters by which the properties of ceramic membranes were evaluated: water absorption, total and open porosity. Standard methods were used to determine these parameters for synthesized samples. The chemical composition of the dry mixture of the ceramic membrane, for which the porosity is the maximum in the series of manufactured samples, was established. It was established that the addition of calcium carbonate components to the dry mixture increases the porosity of ceramic membranes and water absorption. The chemical composition of a ceramic membrane sample with the best indicators of total and open porosity in the KP2 series is given. The chemical and phase composition of samples of the KP2 series, as well as their structural and adsorption characteristics, were investigated by X-ray fluorescence and diffraction methods of analysis and low-temperature nitrogen adsorption-desorption. The effect of the addition of silicon carbide on the characteristics of the porosity of the samples was determined.

Ceramic membrane overview and applications in textile industry: a review.

The importance of water recovery and reuse is increasing day by day. Therefore, the use of advanced technologies is applied for the treatment and recovery of textile wastewater. The fact that ceramic membranes are resistant to the challenging characteristics of textile wastewater makes the use of ceramic membranes useful. Within the scope of this review, general information about the textile industry and treatment techniques are mentioned, as well as the properties of ceramic membranes and textile wastewater treatment. In the literature review made in this study, recent studies on the production of ceramic membranes and laboratory applications have been compiled. However, it has been observed that although the real-scale studies are relatively higher in industries such as the food and petrochemical industry, it is rather limited in the textile industry.

Characterization of ceramic pieces shaped from clay intended for the development of filtration membranes

This research work is focused in study of the dilation/retreat properties of ceramic membranes and its characterization. The clay used in this work is collected in the region of Midelt in Morocco. This raw material has been characterized by XRD, FTIR, TGA/DTA and X-ray fluorescence. These analyzes show that this clay consists essentially of Quartz and Kaolinite. Then, the clay pastes containing different proportions of the organic additive are aged and used to develop rods and bricks of known geometric dimensions. However, the pastilles were developed by dry process. After drying in the open air with a different percentage of the organic matter (0–15%), the parts are treated at different temperatures (700, 800, 900, 1000 and 1050 °C) according to a suitable heating program, taking into account the initial mineralogical composition and the TGA/DTA thermograms of the samples. The dilation/retreat properties of the processed samples are discussed according to the variation of predetermined parameters such as weight loss, length, height and diameter. The evolution of the porosity, the mechanical and chemical resistance of the samples is determined. It has been found that the organic additive increases the porosity of the parts prepared by its degradation by the heat treatment and the results obtained show that the prepared materials have a high mechanical strength and chemical resistance and they have improved porosity. Indeed, the clay studied will be used to develop tubular membranes intended for the tangential filtration of wastewater, which will be the subject of the second part of this study.

The influence of feldspar rock additions on densification and mechanical properties of ceramic membrane using economic raw materials

The influence of feldspar rock additions on densification and mechanical properties of ceramic membrane using economic raw materials

Preparation and Characterization of Silicon Nitride Bonded Silicon Carbide Ultrafiltration Membrane

Silicon nitride-bonded silicon carbide multiphase ceramic ultrafiltration membranes were prepared by using SiC, silicon powder and nitrogen as raw materials and yttrium oxide as sintering aids. The membranes were characterized by XRD and SEM. The effects of different amounts of SiC on the crystal growth and properties of multiphase ceramic ultrafiltration membranes were investigated. When SiC is 10g, silica powder is 0.75g and yttria is 0.5g, the properties of the ceramic membranes are better, and the average pore size distribution is about 0.1μm.1

Ceramic membranes for photocatalytic water purification

The structure and photocatalytic properties of ceramic membranes synthesized on the basis of amorphous potassium polytitanate intercalated with nickel ions have been investigated. It is shown that the phase composition of the synthesized ceramic depends on the firing temperature: at 650°C it forms from NiTiO3, TiO2 and a residual potassium titanate amorphous phase; at 850°C—NiTiO3 crystals, mainly present in the surface layer of TiO2 membranes, and a complex oxide with the composition K(Ti, Ni)O16.5, which has a hollandite structure and is present mainly in the structure of the interior layers of the ceramic.

Preparation of Ceramic Membrane by Micro Arc Oxidation on Mg-Alloy

The article introduces the ceramic membrane technology by micro arc oxidation on Mg-Alloy surface and its properties. The important factors of technical parameters on the properties of ceramic membrane are analyzed. The formation and prevention of defects during the process are also discussed.

Stochastic Reconstruction and Permeation of Ceramic Membranes Prepared by the Sol-Gel Method

ABSTRACTIn the present work we study the relation between structural and permeation properties of ceramic membranes made by the sol-gel process. For this purpose, we have developed γ-Al2O3 mesoporous membranes via the sol-gel route, on top of multi-layer asymmetric α-Al2O3 macroporous supports, to induce mechanical stability. Subsequently, we employ stochastic techniques to generate three-dimensional reconstructions of the membrane and the support that share the basic structural properties of the original materials determined directly from SEM and TEM studies. The permeability of each material is estimated by solving numerically the momentum equation in the void space of the reconstructed images. The very good agreement between predicted and experimentally measured permeability values, without the need to resort to any fitting parameter, renders the proposed reconstruction methodology quite promising for reliable characterization and representation of the pore structure of this type of membranes.