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Tempranillo red wines were partially dealcoholized (−3 v/v%) by osmotic distillation (OD) with membranes. First, polypropylene (PP) Liqui-Cel3M (3M) hollow fiber membrane modules were applied at 11 and 15 °C to study the effect of the removal of ethanol on the aroma of a certain wine. The influence of both temperatures was evaluated in terms of ethanol flux and aroma losses. Afterwards, two additional wines with different compositions were dealcoholized. The impact of the initial concentration of aromas on achieving a final product with an appealing aroma profile was studied, displaying the three wines a comparable aroma retention. Membrane OD was carried out with two additional hollow fiber membrane modules: another PP module (Zena) with a higher pore size, and a superhydrophobic PVDF module (Polymem). The latter gave rise to a partial dealcoholized wine with an aroma profile very similar to that of the pristine wine.

This study presents a sustainable microwave-assisted synthesis, based on the use of acetone and a water/acetic acid mixture instead of typical harmful DMF, to fabricate Zr-metal–organic frameworks (MOFs) UiO-66 and MOF-808 as fillers in a PIM-1 matrix for gas separation application. The mixed matrix membranes (MMMs) were prepared with varying loadings (2.5–10 wt%) of MOFs. The physicochemical properties (1H NMR, FTIR, XRD, N2 adsorption, TGA and SEM) of the resulting PIM-1, MOFs and MMMs were analyzed. The CO2/CH4 separation performance and membrane aging characteristics of the MMMs were evaluated. The incorporation of MOF fillers significantly improved CO2 permeability and CO2/CH4 selectivity, attributed to their CO2-philicity and narrow pore size (UiO-66 ≈ 0.6 nm and MOF-808 ≈ 1.8 nm). The MMMs with higher filler loadings (7.5 and 10 wt%) exhibited the most favorable separation performance. Due to the better crystallinity and textural properties, MOF-808 produced the best separation results at 10 wt% filler loading (a CO2/CH4 separation selectivity of 16.2 at 9090 Barrer of CO2 permeability). Aging led to a decrease in CO2 permeability but a slight increase in CO2/CH4 selectivity for all MMMs. Overall, the study highlights the potential of PIM-1/UiO-66 and PIM-1/MOF-808 MMMs as efficient materials for (CO2/CH4) separation comparing with the pristine PIM-1.

[Background] This work addresses the use of self-supported single-wall carbon nanotube (SWCNT) buckypapers as filters or membranes to treat air or water streams to reduce the concentration of pollutants., [Results] The fabrication of the buckypapers was carried out by a facile filtration method. The performance of the buckypaper as an air filter was tested with a NaCl aerosol obtaining a permeance of 241 m3 m−2 h−1 bar−1 and a filtration efficiency of 99.9991%. The performance of the buckypaper as a water ultrafiltration (UF) membrane was studied separating ZIF-8 nanoparticles of 30, 50 and 120 nm in diameter, achieving a permeance of 124 L·m−2 h−1 bar−1 and a rejection of 99.99%., [Conclusions] A simple technique is described for the rapid fabrication of self-supported SWCNT buckypaper membranes with a filtration method resulting in an excellent performance in both air and water filtration. In addition, because of the acquired control of ZIF-8 crystallization, particles of different sizes of this material were synthesized ad hoc to serve as a reference solute of UF separation.

The development of membranes for nanofiltration applications requires not only selective layers but also suitable supports to control their synthesis as well as to enable efficient and competitive membrane performances. Single-walled carbon nanotube free-standing films (denoted as buckypaper) have been used as supports for the preparation of polyamide (PA) layers by interfacial polymerization (IP) and tested for dead-end nanofiltration for dyes removal (265–1017 Da) from water and organic solvents. The arrangement of the phases during the IP is essential, thus impregnation on the buckypaper support, first with the organic phase and then with the aqueous phase (denoted as inverse IP, iIP) leads to permeances (of up to 28.0 and 31.4 L m−2 h−1 bar−1 for water and methanol, respectively) and rejection values (>96%) that exceed those of the membranes prepared by reversing the impregnation order. Secondly, a double layer PA/zeolitic imidazolate framework (ZIF-8 or ZIF-93) was prepared on the buckypaper (bp). The design of this double layer led to superior membrane performance, in particular for the hydrophilic ZIF-93, as it changes the PA layer properties (increasing both hydrophilicity and surface roughness) providing higher permeances (up to 59.3 and 76.0 L m−2 h−1 bar−1 for water and methanol, respectively) and dye rejections (>98.5%) than the bare PA layer prepared by iIP. This attractive performance of the PA/ZIF-93/bp membrane has been corroborated with experiments in cross-flow nanofiltration and dead-end nanofiltration of aqueous salt solutions, long-term stability nanofiltration and the study the membrane separation performance after a chlorine treatment. The results reported here therefore show the enormous potential of these membrane architectures for a variety of selective separation processes.

We aimed to determine the risk factors for postoperative overactive bladder (OAB) in patients treated with an adjustable trans-obturator male system (ATOMS) for stress incontinence after radical treatment of prostate cancer. A prospective study was performed on 56 patients implanted with an ATOMS for PPI. Clinical and urodynamic information was recorded before and after ATOMS implantation. We built a multivariate model to find out the clinical and urodynamic factors that independently influenced postoperative OAB and the prognostic factors that influenced the efficacy of medical treatment of OAB. We found that the clinical risk factors were the preoperative intensity of urinary incontinence (number of daily pads used and amount of urinary leakage), International Consultation on Incontinence Questionnaire (ICIQ) score, postoperative number of ATOMS adjustments, final cushion volume, and incontinence cure. The urodynamic data associated with OAB were cystometric bladder capacity, voided volume, volume at initial involuntary contraction (IC), maximum flow rate, bladder contractility index (BCI), and urethral resistance (URA). The prognostic factors for the efficacy of oral treatment of OAB were the volume at the first IC (direct relationship) and the maximum abdominal voiding pressure (inverse relationship). The multivariate model showed that the independent clinical risk factors were the daily pad count before the implantation and the ICIQ score at baseline and after treatment. The independent urodynamic data were the volume at the first IC (inverse relationship) and the URA value (direct relationship). Both predictive factors of treatment efficacy were found to be independent. Detrusor overactivity plays an important role in postoperative OAB, although other urodynamic and clinical factors such as the degree of urethral resistance and abdominal strength may influence this condition., Depto. de Cirugía, Fac. de Medicina, TRUE, pub, Descuento UCM

Single-walled carbon nanotube buckypapers (SWCNT-bps) coated with a metal–organic framework ZIF-8 layer were used as supports for the preparation of Pebax® 3533 TFC membranes by both phase inversion and spin coating techniques. Upon proper characterization of the materials by X-ray diffraction, IR spectroscopy, thermogravimetry and electron microscopy, the obtained membranes were tested in gas separation experiments with a 15:85 CO2/N2 mixture. These experiments proved that the ZIF-8 layer prevented from the penetration of the polymer selective film into the SWCNT-bp support, giving rise to a highly permeable selective membrane. The optimum membrane was achieved by the spin-coating method, with better permeation results than that prepared by the phase inversion method, obtaining a CO2 permeance of 566 GPU together with a CO2/N2 selectivity of 20.9.

ZIF-94 is a zeolitic imidazolate framework with the same SOD type topology than ZIF-8 but with an aldehyde group functionalized organic ligand. This turns ZIF-94 less thermally stable than ZIF-8 but with interesting properties of water and carbon dioxide adsorption, making the former a material highly suitable for carbon capture technologies. In this work, an alternative procedure for the synthesis of ZIF-94 was developed based on the use of NaOH as deprotonator. Besides, the crystallization was carried out in a very short time (1–20 min) at room temperature while centrifuging at 10,000 rpm. This made possible the simultaneous crystallization and separation of the product material giving rise, together with the use of the inorganic deprotonator, to a very efficient process with crystallization yields higher than 65%. For the best conditions tested (crystallization-centrifugation time of 5 min), 66 ± 24 nm in particle size, highly crystalline ZIF-94 with 485 m2 g−1 of specific surface area was obtained at a crystallization yield of 66.9%. Similar properties were obtained for ZIF-94 when prepared from recycled reagents (solvent, ligand and Zn salt).

Figure S1. Photographs of the experimental rig for the synthesis of the ZIF-8 layer on the SWCNT buckypaper (A). The buckypaper placed between the disc and the ring (B). ZIF-8 layer being synthesized on the buckypaper (C) at room temperature; Figure S2. Arrhenius model linear fit for the calculation of the apparent activation energy of permeance in the Pebax®/ZIF-8/SWCNT-bp-SC for CO2 (A) and N2 (B). R2 fitting parameter is 0.97 and 0.94, respectively for CO2 and N2; Figure S3. CO2/N2 bound defined in GPU at 35 °C, adapted from the data published in Robeson [7]; Table S1. Gas permeation and selectivity results at 35 °C and 3 bar feed pressure.

Thin film composite (TFC) polyamide (PA) membranes in combination with zeolitic imidazolate frameworks (ZIF), such as ZIF-8 and ZIF-93, have been fabricated using a novel approach based on vapor phase interfacial polymerization (VIP). These membranes have been investigated for nanofiltration (NF) of aqueous solutions of organic dyes, such as Rose Bengal (RB, 1017 Da), Sunset Yellow (SY, 452 Da) and Acridine Orange (AO, 265 Da). The preparation of the PA layer by VIP technique avoids the use of any organic solvent that is typically required in the conventional PA synthesis. Both ZIF-8 and ZIF-93 were initially synthesized using conventional procedures (methanol-based route) and incorporated to the PA layer in two different configurations: i) thin film nanocomposite with ZIF embedded within the PA film, and ii) bilayer membranes with a layer of ZIF between the support and the PA layer. The synthesis of ZIF-93 using a water-based route was developed for the bilayer configuration allowing for an organic solvent-free fabrication of PA/ZIF-93 bilayer VIP-TFC. These membranes showed the highest water permeances of 2.6, 3.4 and 2.2 L m-2h−1 bar−1 for RB, SY and AO, respectively. As compared to the control membrane VIP-TFC, this represents permeance increases of 69–117% and maintains high (greater than 99%) rejection of all the organic dyes. Membrane characterization demonstrated that the permeance enhancement for bilayer PA/ZIF-93 VIP-TFCs is related to an improved hydrophilicity, higher surface roughness and thinner selective layers. The prepared membranes demonstrated excellent cycle stability, maintaining their initial water permeance and dye rejection throughout 34 h of long-term operation, and being able to operate across the entire pH range studied (pH 3 to 9) without any detrimental effects on performance.

This paper presents as main contribution the combination of membrane osmotic distillation (OD) to dealcoholize red wine with hydrophobic-hydrophilic pervaporation (PV) carried out to add value to the wastewater (extracting water) produced in OD, recycling water and generating bioethanol. Membrane OD with a commercial polypropylene hollow fiber module was applied to partially dealcoholize red wine from 14.0 to 11.0 v/v% ethanol. The OD extracting water, containing only ca. 5.3 wt% ethanol, was treated by sequential PV with both hydrophobic (PDMS or zeolite silicalite-1) and hydrophilic (zeolites mordenite or faujasite) membranes. This hydrophobic-hydrophilic PV produced two main products: bioethanol (recovering 88% of the ethanol removed from the wine) and a 99.4 wt% water-rich product. This water-rich product, with a very low ethanol content, was used as extracting water in the OD, giving rise to an analogous partially dealcoholized wine, in terms of aroma contents (as determined by gas chromatography for 25 compounds), to that achieved when using fresh water.