Development and characterization of tubular composite ceramic membranes using natural alumino-silicates for microfiltration applications

Abstract

The preparation and characterization of porous tubular ceramic composite microfiltration membranes, using kaolins and calcium carbonates, were reported. The porous gehlenite (2CaO·Al 2 O 3 ·SiO 2 ) and anorthite (CaO·Al 2 O 3 ·2SiO 2 ) based ceramics were obtained by a solid state reaction. A ceramic support, sintered at 1250°C, within an average pore size of about 8 μm, a porosity of about 47% and a compression strength around 40 MPa, was prepared. The microfiltration active top layer was added on the support by a slip casting from clay powder suspensions. The novel microfiltration membrane layer has a thickness of 40 μm and an APS value of about 0.2 μm. This average pore size value was improved and considerably lower than those reported in the literature (0.5 μm). The performance of the novel microfiltration ceramic membrane was determined for evaluating both the water permeability and rejection. This proved the potentiality of the membrane produced in the microfiltration field. Moreover, the good adhesion, between the support and the active microfiltration layer membranes, was also proved. A correlation between microstructures of used powders and physicochemical properties was discussed. Finally, the origin of the unique two powder order membrane depositions was also proposed.

Mechanical properties of anorthite based ceramics prepared from kaolin DD2 and calcite

“…The new elaborated microfiltration membrane layer has a thickness of about 40 μm and an average pore size (APS) value of about 0.2 μm. The performance of the new microfiltration ceramic membrane was determined by evaluating both the water permeability and rejection [42]. This proved the potentiality of the membrane produced in the microfiltration field.…”

“…In this work, the long-term goal is the development of a low cost anorthite from inexpensive raw materials, such as kaolin and calcite (CaCO 3 ) using a modified milling system. Many works have already been published for appreciating these native raw materials including bioceramics [9][10][11][12][13][14][15][16][17], advanced ceramics [18][19][20][21][22][23][24][25][26][27] and ceramic membranes [28][29][30][31][32][33][34][35][36][37][38][39][40][41][42]. Most of these publications are closely related to this work and clearly highlight their possible applications.…”

“…As far as ceramic membranes publications are concerned [28][29][30][31][32][33][34][35][36][37][38][39][40][41][42], a lot of low cost materials were also fabricated using the abundantly available raw materials as mentioned above. More recently, porous tubular ceramic composite microfiltration membranes were prepared by an extrusion method using kaolin and calcium carbonates as starting materials, carried out in [42]. The porous gehlenite (2CaO.Al 2 O 3 .SiO 2 ) and anorthite based ceramics were obtained by a solid-state reaction.…”

Membranas cerámicas de bajo coste para el tratamiento de aguas residuales

“…Normalmente, se usan derivados de la celulosa como ligantes (metilcelulosa, carboximetilcelulosa, etc.,) y polímeros orgánicos como plastificantes o lubricantes (polivinil alcohol, polietilenglicol, etc.,) [4,22,112]. Existen también productos derivados del almidón que se emplean en numerosos trabajos como ligantes (por ejemplo, amijel Cplus 12072, Cerestar) [22,31,38,53,115].…”

“…Así, se han obtenido capas a partir de arcilla procedente de Túnez [45,118], caolín procedente de Argelia [115], margas limosas [119], apatita [78], anortita [55], tierra de diatomea [67], fosfatos [75] e incluso composiciones con diferentes materias primas (arcilla, bentonita, alúmina y cuarzo) [48] o residuos de la industria de fosfatos [86].…”