Characterization of meso- and macroporous ceramic membranes in terms of flux measurement: A moment-based analysis

MCM-41 “LUS”: Alumina Tubular Membranes for Metal Separation in Aqueous Solution

“…The proton concentration (pH) was monitored potentiometrically by means of a glass electrode. The experimental setup used to carry out these tests is similar to that used in a previous study . At excess HCl concentration in the feed stream, the proton diffusion pattern can be modeled as ln false( normalΩ false) = ln true[ C H F false( 0 false) − C H P false( t false) C H F false( 0 false) − C H P false( 0 false) true] ≈ − ε D̅ HCl τ l S V 2 t with the time lag (θ H ) defined by the expression θ H = τ l 2 6 ε D̅ HCl In eqs and , the term τ l /ε D̅ HCl corresponds to the overall resistance of the membrane system (support + active layer) to the transfer of the electrolyte.…”

“…The experimental setup used to carry out these tests is similar to that used in a previous study. 55 At excess HCl concentration in the feed stream, the proton diffusion pattern can be modeled as with the time lag (θ H ) defined by the expression In eqs 2 and 3, the term τl/εD j HCl corresponds to the overall resistance of the membrane system (support + active layer) to the transfer of the electrolyte. This parameter can be expressed as a combination in series of the corresponding resistances of the support and the active layer The HCl diffusivity in eqs 2-4 can be expressed as a function of the H + and Cldiffusivities under aqueous solvation using an expression derived from the Nernst-Planck equations for a monovalent electrolyte The combination of the slopes in eqs 2 and 3 allows the determination of the overall membrane thickness as 2.7.…”

Zeolite Composite Membranes with a Nanoporous Fluorinated Carbonaceous Sheath for Organic Solvent Filtration

“…Porous ceramic membranes, e.g., α-Al 2 O 3 , ZrO 2 , and TiO 2 , have been commercially applied in the micro- and ultrafiltration processes, such as Membralox. However, pristine ceramic filtration membranes usually bearing an asymmetric structure are often not competent for concentrating nonaqueous solutions owing to the low permeability and selectivity caused by the nanoporous selective layer comprising of rigid nanopores developed by sol-gel dip-coating , and hydrothermal synthesis approaches. The resulting nanopores lack the necessary chemical character and are often inherently hydrophilic, which therefore calls for a surface functionalization step to implement various organic functional groups over the pore surface or/and membrane surface by applying organic reactions.…”

High virus retention mediated by zirconia microtubes with tailored porosity

“…However, the cost factor can be compensated by the long-term stability of the ceramic membranes and the obtained high membrane permeate fluxes. [10][11][12][13][14] Based on the membrane geometry and outer diameter, tubular membranes are classified into hollow fibres (<0.5 mm), capillaries (0.5-5 mm) and tubes (>5 mm). They feature a high surface area/volume ratio and an easy scale up as compared to flat-sheet membranes.…”