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The 12 Principles of Green Chemistry act as a guide for chemists for the design and synthesis of sustainable product. Adoption by chemist is essential for the transition. We chose...

This work concerns the preparation of a mineral membrane by the slip casting method based on zirconium oxide (ZrO2) and kaolin. The membrane support is produced from a mixture of clay (kaolin) and calcium carbonate (calcite) powders using heat treatment (sintering). Membrane and support characterization were performed by Scanning Electron Microscopy (SEM), X-ray Fluorescence (XRF), Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), and Raman Spectroscopy. The prepared mineral membrane was tested to treat drinking water obtained from different zones of the El Athmania (Algeria) water station (raw, coagulated, decanted, and bio filtered water). Experimental parameters such as permeate flux, turbidity, and total coliforms were monitored. The results showed that the mineral membrane was mainly composed of SiO2 and Al2O3 and the outer surface, which represented the membrane support, was much more porous than the inner surface where the membrane was deposited. The permeate flux of the raw water decreased with filtration time, due to a rejection of the organic matters contained in the raw water. Moreover, the absence of total coliforms in the filtrate and the increase in concentration in the concentrate indicate that the prepared mineral membrane can be used for drinking water treatment.

In this study, we investigated the effect of different organic binders on the morphologic structure of ceramic membrane support. Natural raw clay material (kaolin) was used as the main mineral for ceramic membrane support. The physical and chemical properties of kaolin powder and the supports were identified by X-ray fluorescence (XRF), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), Brunauer–Emmett–Teller (BET), thermo gravimetric analysis (TGA), scanning electron microscopy (SEM), particle size and zeta potential distribution. Based on the XRF test, the main composition of kaolin powder was SiO2 (47.41%) and Al2O3 (38.91%), while the rest were impurities. The FTIR spectra showed the functional groups of Si-O and Al-O. The XRD diffractogram of natural raw clay powder identified kaolinite and nacrite were the main mineral phase whereas muscovite and quartz were detected in small quantities in the sample. After prepared the ceramic membrane supports, XRD diffractogram showed that anorthite and gehlenite were detected as the main mineral phases for ethylene glycol (EG), gelatin, methocel and for polyethylene glycol (PEG), respectively. According to BET analyses, the maximum and the minimum pore width were obtained for PEG and gelatin organic binders.

A multilayer polyelectrolyte ceramic membrane using LbL was assembly to test performance of water disinfection capability. The natural raw clay material (kaolin) was used as the main ceramic membrane (CM)support. The impact of the number of polyelectrolyte bilayers (2, 4, 6) on the retention of E. coli was systematically investigated. Test results showed water permeability coefficients (Lp) were 85.3 L/m2.h.bar and 69.5, 28.3, 50.1 L/m2.h.bar for pristine (CM0) and ceramic membranes with 2-bilayers (CM2), 4-bilayers (CM4), 6-bilayers (CM6), respectively. Complete retention of E. coli was achieved by the multilayer polyelectrolyte ceramic membrane with 4 bilayers. The surface morphology of the multilayer polyelectrolyte ceramic membrane was identified by scanning electron microscopy (SEM). The results showed that the multilayer polyelectrolyte ceramic membrane can be safely applied in providing water disinfection.