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A novel ceramic microfiltration (MF) membrane was prepared from natural phosphate and its properties were thoroughly characterized. An investigation of the effect of sintering temperature on the features of phosphate membrane was carried out in the range from 900 to 1100 °C. The optimized membrane sintered at 1000 °C exhibits 697 L h−1 m-2 bar−1 of permeability, 25.6 % of porosity, 0.26 μm of average pore size and 19.7 MPa of flexural strength. When evaluated for filtration of raw seawater as a potential pretreatment for reverse osmosis desalination, the prepared membrane reduced total organic carbon (TOC) and turbidity by 73 and 98 %, respectively, as well as reducing silt density index (SDI) from 5.41 to 3.25. Furthermore, the fouling mechanism and the flux recovery were also studied. Finally, simple cleaning of the prepared membrane performed after the MF experiment led to recover 74 % of its original water flux.

Drinking water treatment sludge (DWTS) was used for the preparation of ceramic microfiltration membrane. The DWTS powder was firstly characterized to determine its chemical and mineralogical composition, and to understand its thermal behavior. DWTS powder was mixed with clay as binder and starch as porosity agent, then pressed to shape flat membrane, and sintered at different temperatures from 950 to 1150 °C. The optimal sintering temperature (1050 °C) provides ceramic membrane with a porosity of 46.7%, a pore size of 0.92 μm, a mechanical strength of 14.5 MPa and a permeability of 724.5 L/h.m2.bar. This membrane was successfully used to clarify a synthetic baking powder suspension and an textile effluent. DWTS-based membrane was able to remove completely the turbidity from feeds, to reduce significantly the chemical oxygen demand (COD), and to discolor completely textile wastewater. Furthermore, four empirical models were applied to describe the fouling mechanism occurred during filtration experiments.

International audience; The aim of this work is the manufacturing of flat microfiltration membrane made from Moroccan natural kaolinite clay and corn starch as porosity agent. The membrane was prepared by uniaxial pressing technique and sintering at 1,100 degrees C. The effect of starch on membrane features was investigated from 0 to 15 wt.%. The membrane has a diameter of 37.8 mm and a thickness of 2.3 mm. In order to optimize its properties, prepared membrane was characterized in terms of apparent porosity, water absorption, apparent density, mechanical strength, pore size, microstructure, and water permeability measurements. Experimental results showed that the membrane prepared with 10 wt.% of starch is considered as an optimized membrane which has an average pore size of 2.3 mu m, the mechanical strength of 20.2 MPa, and permeability of 2,129 L h(-1)m(-2) bar(-1). The optimized membrane was applied for pretreatment of raw seawater for desalination and clarification of agro-food effluent using dead-end filtration under pressure of 0.12 bar. Filtration results showed that turbidity rejection achieves 73% and 99%, respectively for raw seawater and agro-food model effluent.

This study concerns the development and characterization of composite ultrafiltration membrane made of polymer blend of polysulfone (PSf) and polyetherimide (PEI) as membrane layer and flat pozzolan support. The organic layer was deposed on ceramic support by spin/spray-coating method. The effect of PEI content (5–20 wt.%) on membrane proprieties in terms of microstructure and filtration performance was investigated. The prepared membrane was characterized using several techniques such as Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance spectroscopy (NMR), scanning electron microscope (SEM) and contact angle. The morphology analysis showed that PSf/PEI membrane layer is homogeneous and strongly adherent on the pozzolan support. The thickness layer is uniform and found to be between 10.3 and 11.2 μm. Furthermore, performances of the prepared composite membranes were evaluated by filtration of acid orange 74 (AO74) and methyl orange (MO) solutions at pressure of 3 bar. The optimized membrane (prepared with 20 wt.% of PEI) has water permeability of 24.2 L/h m2 bar and maximum rejection of 96.1 and 75.8% respectively for AO74 and MO. Based on promising filtration results as well as the low cost of prepared membrane, industrial applications for treatment of wastewater particularly colored wastewater generated from textile industries may take place.

This work describes the elaboration of flat ceramic microfiltration membrane based on natural perlite for microfiltration of industrial wastewater. The ceramic membrane was obtained by an uniaxial pressing process and sintering at optimized temperature. The sintering temperature was investigated in the range from 850 to 1050 °C. The elaborated membrane of 38.4 mm in diameter and 2.2 ± 0.3 mm in thickness was characterized by environmental scanning electron microscopy (ESEM), porosity, water permeability, mechanical strength, and chemical resistance. The porosity of optimized membrane (sintered at 950 °C) is 52.11% with an average pore size of 1.70 μm. The water permeability reached a value of 1433.46 L/hm2.bar. In addition, the membrane has a mechanical resistance of 21.68 MPa and exhibits good chemical resistance both in an acidic and basic medium. The performance of prepared membrane was evaluated by frontal microfiltration of two industrial wastewater effluents (agro-food and tannery). Experimental results show that retention of turbidity was superior to 97 and 96% respectively for agro-food and tannery effluents. The filtration results are quite promising that could allow using the prepared membrane as an alternative process in industrial wastewater treatment.

This paper reports the preparation and characterization of a low-cost nano-TiO 2 ultrafiltration membrane deposited on a bentonite support. The ultrafiltration layer was obtained by dip-coating process using nano-TiO 2 , followed by sintering at 750 °C. Environmental Scanning Electron Microscope (ESEM) analysis of prepared ultrafiltration membrane showed that the deposited layer is homogeneous and shows a good adhesion on the support presenting a mean thickness of 4 ± 0.2 μm. The average pore diameter and water permeability of the obtained membrane are respectively 10 ± 0.5 nm and 16.08 L/h m 2 bar. The membrane performance was evaluated by filtration of three different dyes: two anionic (Direct red 80 and Acid orange 74) and a cationic one (Methylene blue). Effect of feed pH and dyes concentration on membrane rejection was investigated at a pressure of 4 bar. The experimental filtration results showed that rejection of Direct Red 80, Acid Orange 74 and Methylene Blue achieved maximum values of 98%, 85% and 94% respectively, depending on filtration conditions and each dye characteristics.

The present work reports the preparation and characterization of flat ceramic membrane via dry pressing method made from natural phosphate as based material and kaolinite as additive to enhance membrane characteristics. Response surface methodology based on Box–Behnken design was used to optimize the preparation conditions notably amount of kaolinite (5–15 wt%), sintering temperature (900–1000 °C) and time of sintering (2–4 h). The optimized membrane has 40.2 MPa of flexural strength, 41.3% of porosity, 1045 L h−1 m−2 bar−1 of permeability and 0.35 µm of average pore size. The phosphate/kaolinite membrane was subjected to the filtration of industrial textile wastewater and it showed excellent performance as microfiltration membrane. It is able to remove 98.99% of turbidity, 69.39% of total organic carbon, 74% of chemical oxygen demand and 77.11% of biological oxygen demand.

The development of high performance ultrafiltration membranes using low-cost products and naturally abundant materials has utmost importance for sustainable development and environmental applications. In this work, a new composite membrane was successfully synthesized by deposition of a polypyrrole layer on a flat porous support based on a natural geomaterial. The thin layer of polypyrrole was synthesized by the chemical polymerization of pyrrole. The obtained composite membrane was characterized by Infrared Spectroscopy, X-Ray Diffraction and energy dispersive X-Ray analysis to confirm the polymerization reaction of pyrrole. Scanning electron microscopy and contact angle that the membrane surface has typical cauliflower morphology with 20 μm in thickness and high hydrophobicity (108°). The performance of the polypyrrole membrane in terms of dye permeance and effluent textile treatment was investigated by measurement of the water permeability and congo red rejection from aqueous solutions. Experimentally, the water permeability reaches 10.3 ± 3 L/m2.h.bar, and the polypyrrole membrane removes up to 98 % of congo red at optimized conditions.

γ alumina microporous membranes, produced from a sol–gel process, were grafted by means of chloro-, methoxy- or ethoxy-organosilanes. The grafting conditions were first tested on γ alumina powders which were characterised by means of thermogravimetric analysis and nitrogen adsorption. The membrane material was studied by means of infrared spectrometry, nitrogen adsorption and nitrogen permeation. The performances of grafted and ungrafted membranes were examined for the separation by pervaporation of binary mixtures such as water/ethanol, cyclohexane/toluene, ethanol/cyclohexane and methylethylketone/cyclohexane.