Sol was analysed with a dynamic light-scattering method using a Zetasizer Nano ZS device (Malvern Instruments, Worcestershire, UK). Stability of particle distribution has been found after long-term storage. The membrane was impregnated with sol, treated with a NH4OH solution (1,000 mol m−3), dried at ≈ 298 K and heated at 423 K [6, 7]. A layer of the ion exchanger was removed from
the outer surface of the membrane with ultrasonic activation at 30 kHz. The procedure, which involves impregnation, HZD deposition, drying, heating and ultrasonic treatment, was repeated two and seven times. The samples were marked as TiO2 (matrix), TiO2-HZD-2 and TiO2-HZD-7 (modified membranes). Similar growth of HZD content (2.2 to 2.4 mass%) was reached both for TiO2-HZD-2 (in comparison with the matrix) and TiO2-HZD-7 (in comparison with TiO2-HZD-2). RG7204 molecular weight Electron microscopy SCH772984 nmr After dehydration of sol at room temperature, its solid constituent was investigated using a JEOL JEM 1230 transmission electron microscope (JEOL Ltd., Tokyo, Japan). Finely dispersed powders obtained both from initial and modified membranes were also researched. Before the investigations, the powders of ceramics were treated with a CH3COOH solution (100 mol m−3) to shade the modifier particles.
Transverse section of the membranes was investigated using a Zeiss EVO 50XVP scanning electron microscope (Carl Zeiss AG, Oberkochen, Germany). Small-angle X-ray scattering Finely dispersed powders of the membranes were inserted into cuvettes, the thickness of which was 0.1 to 0.2 mm, with 17-μm-thick Mylar windows. Small-angle X-ray scattering (SAXS) curves were obtained in a vacuum Kratky camera using a Cu-anode tube. Recording of SAXS data has been carried out under the conditions of multiple scanning Progesterone of a scintillation detector at scattering angles of 0.03° to 4.0°. The first treatment of the SAXS data was carried out by means of the FFSAXS11 program. The exclusion of parasitic scattering
by the camera and cuvette windows, normalization of the scattered intensity to absolute units, and the introduction of the collimation correction were performed. Standard contact porosimetry The membranes were heated at 423 K before the measurements. Octane was used as a working liquid [8–11]. The curves of differential pore volume (V) distribution ( , where r is the pore radius) were resolved by Lorentz components using the PeakFit v. 4.12 program. Treatment of the curves involved resolution within the intervals of pore radius of 1 to 100 nm and 1 to 105 nm and comparison of the data for peaks with a maximum at ≈ 100 nm. Data adequacy is confirmed by coincidence of these maxima in two diapasons and high correlation coefficient (0.99). This procedure was necessary because the values are rather low at 1 to 100 nm.