Utilization of Smartphone Light Sensors as Light Transmission Analyzer During the Obtaining of Polymeric Phase Inversion Membranes

2020 ◽  
Vol 43 (3) ◽  
pp. 5-9
Author(s):  
Ștefan PINTILIE ◽  
◽  
Geanina Laurenția PINTILIE ◽  
Ștefan BALTĂ ◽  
◽  
...  
Keyword(s):  
Phase Inversion ◽  
Light Transmission ◽  
Pure Water ◽  
Light Transmittance ◽  
Membrane Properties ◽  
Water And Wastewater Treatment ◽  
Sem Images ◽  
Cross Sectional ◽  
Polysulfone Membrane ◽  
Best Available Technologies

Smartphone sensors are gaining research interest due to continuous sensor upgrades, leading to more precise readings of these sensors. For this study, the light sensor of a smartphone was used in determining light transmittance during the phase inversion process of ultrafiltration polysulfone - membrane manufacturing. Membrane separation is one of the best available technologies when it comes to water and wastewater treatment. The purpose of this study was to correlate light transmit tance, at certain demixing steps during phase inversion, with membrane porosity, pure water flux and cross - sectional SEM images. Results show close relation between light transmittance and the mentioned membrane properties.

Study on the Fabrication of Superhydrophobic Microporous Polypropylene Flat Membrane Using In Situ Synthesis of Modified Fluorinated Silica Nano Particles

2013 ◽  
Vol 829 ◽  
pp. 371-375 ◽  
Author(s):  
Saba Raveshiyan ◽  
Reza Yegani ◽  
Behzad Pourabbas ◽  
Akram Tavakkoli
Keyword(s):  
Pure Water ◽  
Sol Gel ◽  
Nano Particles ◽  
Sem Images ◽  
Cross Sectional ◽  
Transfer Resistance ◽  
Thermally Induced ◽  
Coated Membranes ◽  
Membrane Contactors

The wettability is the most important features of membrane, when it works as contactors. Although the membrane contactors offer many advantages over conventional contacting equipments, additional mass transfer resistance is introduced when micropores are filled with aqueous absorbents. Therefore, fabrication of superhydrophobic membrane which prevents diffusion of aqueous absorbent into membrane pores is a highly challenging task. In this work, superhydrophobic polypropylene (PP) membrane was fabricated using in situ synthesis of silica nano particles via thermally induced phase separation (TIPS) method. Flat sheet fabricated PP membranes were casted with methanolic solution containing various ratios of perfluorooctyltriethoxysilane (PFOTES)/ tetraethylortosilicate (TEOS) and then sol-gel reaction between the mixed silances was completed. The contact angle of coated membrane was reached to 168 degree, when the percentage of PFOTES/TEOS was fixed at 50% (mol/mol). Interestingly, due to the microporous structure of PP membrane, the synthesized fluorinated silica nanoparticles were observed on the surface as well as in the cross-sectional area of the membrane. Field emission scanning electron microscopy (FE-SEM) images were confirmed this point. Chemical structure of the coated membranes with 50% PFOTES was compared with pure PP membrane using ATR-IR. In order to evaluate the operational performance, coated membranes were immersed in aqueous solutions of mono ethanol amine (MEA), di ethanol amine (DEA) and pure water. In comparison with pure PP membrane, obtained results showed that the wettability of coated membranes was considerably decreased.

scholarly journals Characteristic properties of ceramic membrane derived from fly ash with different loadings and sintering temperature

2019 ◽  
Vol 15 (3) ◽  
pp. 414-420
Author(s):  
Siti Nur Afiqah Zulkifli ◽  
Azeman Mustafa ◽  
Mohd Hafiz Dzarfan Othman ◽  
Siti Khadijah Hubadillah
Keyword(s):  
Fly Ash ◽  
Mechanical Strength ◽  
Phase Inversion ◽  
Ceramic Membrane ◽  
Sintering Temperature ◽  
Pure Water ◽  
Bending Test ◽  
Sintering Process ◽  
Cross Sectional ◽  
Water Separation

Nowadays, ceramic membrane developed from wastes has gained attention, especially towards water separation applications. With abundant and high silica content of fly ash, low cost ceramic membrane was successfully prepared via phase inversion and sintering technique. Prior to both phase inversion and sintering process, ceramic suspension was prepared at different loadings, ranging from 40wt% to 50 wt% fly ash and subsequently sintered at temperature ranging from 1150°C to 1350°C. By varying fly ash content and sintering temperature, the morphology, mechanical strength and phase transformation characteristics of the prepared membrane were affected. The characterisation of prepared membrane were investigated by using scanning electron microscopy, three-point bending test, and X-ray diffraction (XRD). The mechanical strength of the membrane increased with increasing fly ash loading (up to 45 %), however too much fly ash loading resulted in decrease of its mechanical strength probably due the presence of unburnt at higher fly ash contents. This unburnt carbon contributed to the vacant space during sintering process and had the tendency to increase formation of pores, simultaneously reduced its mechanical strength. In addition, the SEM results also illustrated a cross-sectional image of the membrane which had become more elastic with increasing fly ash loading and denser as sintering temperature gradually increased. In addition, increasing the fly ash loading likely discouraged the formation of desired finger-like structure. The XRD results however showed continuous presence of mullite with the increasing sintering temperature which contributed higher mechanical strength. The preliminary performance tests indicated that the optimum conditions to produce hollow fibre ceramic membrane from fly ash were at 45 wt % fly ash loading sintered at 1350°C and has a pure water flux of 131 L/m2h.

scholarly journals Dynamics of Melting Process in Phase Change Material Windows Determined Based on Direct Light Transmission

Energies ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 721
Author(s):  
Dariusz Heim ◽  
Michał Krempski-Smejda ◽  
Pablo Roberto Dellicompagni ◽  
Dominika Knera ◽  
Anna Wieprzkowicz ◽  
...  
Keyword(s):  
Phase Change ◽  
Phase Change Material ◽  
Light Transmission ◽  
Melting Process ◽  
Refraction Index ◽  
Light Transmittance ◽  
Reference Case ◽  
Solar Radiation Intensity ◽  
Direct Light ◽  
Change Material

Detailed analyses of melting processes in phase change material (PCM) glazing units, changes of direct transmittance as well as investigation of refraction index were provided based on laboratory measurements. The main goal of the study was to determine the direct light transmittance versus time under constant solar radiation intensity and stable temperature of the surrounding air. The experiment was conducted on a triple glazed unit with one cavity filled with a paraffin RT21HC as a PCM. The unit was installed in a special holder and exposed to the radiation from an artificial sun. The vertical illuminance was measured by luxmeters and compared with a reference case to determine the direct light transmittance. The transmittance was determined for the whole period of measurements when some specific artefacts were identified and theoretically explained based on values of refractive indexes for paraffins in the solid and liquid state, and for a glass. The melting process of a PCM in a glass unit was identified as a complex one, with interreflections and refraction of light on semi layers characterized by a different physical states (solid, liquid or mushy). These optical phenomena caused nonuniformity in light transmittance, especially when the PCM is in a mushy state. It was revealed that light transmittance versus temperature cannot be treated as a linear function.

THE FEASIBILITY OF KAOLIN AS MAIN MATERIAL FOR LOW COST POROUS CERAMIC HOLLOW FIBRE MEMBRANE PREPARED USING COMBINED PHASE INVERSION AND SINTERING TECHNIQUE

2017 ◽  
Vol 79 (1-2) ◽  
Author(s):  
Siti Khadijah Hubadillah ◽  
Mohd Hafiz Dzarfan Othman ◽  
A. F. Ismail ◽  
Mukhlis A. Rahman ◽  
Juhana Jaafar
Keyword(s):  
Phase Inversion ◽  
Low Cost ◽  
Pure Water ◽  
Porous Ceramic ◽  
Water Flux ◽  
Hollow Fibre ◽  
Hollow Fibre Membrane ◽  
Fibre Membrane ◽  
Pure Water Flux ◽  
And Performance

Ceramic hollow fibre membrane (CHFM) demonstrated superior characteristics and performance in any separation application. The only problem associated with this kind of technology is the high cost. In order to effectively fabricate and produce low cost porous CHFM, a series of CHFMs made of kaolin were fabricated via combined phase inversion and sintering technique. The CHFMs from kaolin named as kaolin hollow fibre membranes (KHFMs) were studied at different kaolin contents of 35 wt.%, 37.5 wt.% and 40 wt.% sintered at 1200ºC. The result indicated that by varying kaolin contents, different morphologies were obtained due to changes in the viscosity of ceramic suspension containing kaolin. The optimum kaolin content for KHFM was identified. It was found that KHFM prepared at 37.5 wt% has a mechanical strength and pure water flux of A and B respectively.  

scholarly journals Incorporation of Lipids into Wheat Bran Cellulose/Wheat Gluten Composite Film Improves Its Water Resistance Properties

Membranes ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 18
Author(s):  
Guanghui Shen ◽  
Guoxian Yu ◽  
Hejun Wu ◽  
Shanshan Li ◽  
Xiaoyan Hou ◽  
...  
Keyword(s):  
Composite Film ◽  
Wheat Bran ◽  
Food Packaging ◽  
Water Resistance ◽  
Wheat Gluten ◽  
Vapor Permeability ◽  
Scanning Calorimetry ◽  
Sem Images ◽  
Water Contact ◽  
Cross Sectional

This work evaluated the improvement effects of lipids incorporation on water resistance of composite biodegradable film prepared with wheat bran cellulose/wheat gluten (WBC/WG) using an alkaline–ethanol film forming system. Four types of lipids, paraffin wax (PW), beeswax (BW), paraffin oil (PO), and oleic acid (OA), were tested. We found that PW, BW, and PO incorporation at 5–20% improved water vapor permeability (WVP) and surface hydrophobicity of prepared films. Particularly, incorporation of 15% BW could best improve the water resistance properties of the film, with the lowest WVP of 0.76 × 10−12 g/cm·s·Pa and largest water contact angle (WCA) of 86.18°. Incorporation of OA led to the decline in moisture barrier properties. SEM images revealed that different lipids incorporation changed the morphology and of the composite film, and cross-sectional morphology indicated BW-incorporated film obtained more uniform and compact structures compared to other films. Moreover, Fourier transform infrared spectra indicated that the incorporation of PW or BW enhanced the molecular interactions between the film components, confirmed by the chemical shift of characteristic peaks at 3277 and 1026 cm−1. Differential scanning calorimetry results revealed that incorporation of PW, BW, and PO increased films’ melting point, decomposition temperatures, and enthalpy values. Furthermore, the presence of most lipids decreased tensile strength and elongation at the break of the film. Overall, the composite film containing 15% BW obtained the most promising water resistance performance and acceptable mechanical properties, and it thus most suitable as a hydrophobic biodegradable material for food packaging.

scholarly journals Preparation and Characterization of MWCNTs/PVDF Conductive Membrane with Cross-Linked Polymer PVA and Study on Its Anti-Fouling Performance

Membranes ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 703
Author(s):  
Yi Ding ◽  
Zhansheng Guo ◽  
Xinan Dong ◽  
Hong You ◽  
Junxue Mei ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Mass Loss Rate ◽  
Pure Water ◽  
Water Flux ◽  
Membrane Properties ◽  
Elongation Ratio ◽  
Functional Layer ◽  
Conductive Membranes ◽  
Pure Water Flux ◽  
Conductive Membrane

Based on carboxylated multi-walled carbon nanotubes (MWCNTs-COOH), a MWCNTs/PVDF conductive membrane was prepared by a vacuum filtration cross-linking method. The surface compositions and morphology of conductive membranes were studied by X-ray photoelectron spectroscopy and high-resolution field emission scanning electron microscopy, respectively. The effects of cross-linked polymeric polyvinyl alcohol (PVA) on the conductive membrane properties such as the porosity, pore size distribution, pure water flux, conductivity, hydrophilicity, stability and antifouling properties were investigated. Results showed that the addition of PVA to the MWCNTs/PVDF conductive membrane decreased the pure water flux, porosity and the conductivity. However, the hydrophilicity of the modified MWCNTs/PVDF conductive membrane was greatly improved, and the contact angle of pure water was reduced from 70.18° to 25.48° with the addition of PVA contents from 0 wt% to 0.05 wt%. Meanwhile, the conductive membranes with higher content had a relatively higher stability. It was found that the conductive functional layer of the conductive membrane had an average mass loss rate of 1.22% in the 30 min ultrasonic oscillation experiment. The tensile intensity and break elongation ratio of the conductive membrane are improved by the addition of PVA, and the durability of the conductive membrane with PVA was superior to that without PVA added. The electric assisted anti-fouling experiments of modified conductive membrane indicated that compared with the condition without electric field, the average flux attenuation of the conductive membrane was reduced by 11.2%, and the membrane flux recovery rate reached 97.05%. Moreover, the addition of PVA could accelerate the clean of the conductive membranes.

Effect of solution chemistry and operating conditions on the nanofiltration of acid dyes by a nanocomposite membrane

2011 ◽  
Vol 64 (12) ◽  
pp. 2404-2409 ◽  
Author(s):  
A. Akbari ◽  
M. Homayoonfal ◽  
V. Jabbari
Keyword(s):  
Uv Irradiation ◽  
Separation Efficiency ◽  
Irradiation Time ◽  
Membrane Surface ◽  
Operating Conditions ◽  
Solution Chemistry ◽  
Polymerization Process ◽  
Inversion Method ◽  
Sem Images ◽  
Polysulfone Membrane

A composite nanofiltration membrane was developed by a poly(acrylic acid) in situ ultraviolet (UV) graft polymerization process using an ultrafiltration polysulfone membrane as a porous support, by a phase inversion method. SEM images showed that the PSf membranes had numerous finger-like pores. Atomic force microscopy (AFM) showed that the roughness of the surface was reduced by an increase in UV irradiation times. The rejections of sodium chloride and sodium sulfate were moderate and declined with the increase of concentration. We observed that by increasing UV irradiation time and nanofiltration pressure applied, retention of dyes was enhanced and in the most irradiated membrane (M-4 membrane) at 4 bars, color removal with a high rejection of about 99.80% was achieved. It was found that the separation efficiency of dyes in the mixture of salt and dyes decreased with the salt concentration due to a decrease in the Donnan effect. It was also found that by varying the pH, the membrane surface and the dyes' charges are changed, which meant that the membrane surface and dyes had different interactions at various pHs.

Proton Exchange Membrane Development and Processing for Fuel Cell Application

2007 ◽  
Vol 539-543 ◽  
pp. 1327-1331
Author(s):  
Philippe Bébin ◽  
Hervé Galiano
Keyword(s):  
Fuel Cell ◽  
Proton Conductivity ◽  
Proton Conduction ◽  
Proton Exchange ◽  
Membrane Properties ◽  
Organic Polymer ◽  
Polysulfone Membrane ◽  
Sulfonated Polysulfone ◽  
Membrane Processing ◽  
Conductive Fillers

The development of new proton exchange membranes for PEMFC has to be related to the membrane processing as it can change drastically the final properties of the material. Indeed, for the same material, a membrane prepared by a solvent-casting process has a lower lifetime than an extruded one. The proton conduction of the membrane can also be dependent on the membrane processing, especially when some removable plasticizers are used to perform the membrane extrusion. Some residual porosity, left in the material after removing the plasticizer, is suspected to enhance the proton conduction of the film. Fuel cell experiments have shown that extruded sulfonated polysulfone membrane can give the same performance as a Nafion® reference membrane whereas the proton conductivity of PSUs is twenty times lower than the Nafion® one. Additional improvements of the membrane properties can also be expected by adding some proton conductive fillers to the organic polymer. This approach enhances the proton conductivity of sulfonated polysulfone to values similar to Nafion®. On the other hand, when Nafion® is used as a matrix for the proton conductive fillers, a very significant improvement of fuel cell performance is obtained.

The Optimization of RHS-polysulfone Membrane towards Operating Condition for Humic Acid Removal

2021 ◽  
Vol 02 (01) ◽  
Author(s):  
Mohd Riduan Jamalludin ◽  
◽  
Siti Khadijah Hubadillah ◽  
Zawati Harun ◽  
Muhamad Zaini Yunos ◽  
...  
Keyword(s):  
Response Surface Methodology ◽  
Ionic Strength ◽  
Membrane Separation ◽  
Pure Water ◽  
Water Flux ◽  
Separation Process ◽  
Transmembrane Pressure ◽  
Polysulfone Membrane ◽  
Optimal Value ◽  
Pure Water Flux

This study investigates the effects of rice husk silica (RHS) as additive in the polysulfone membrane to enhance antifouling properties in membrane separation process. The performance (of what?) was evaluated in term of pure water flux (PWF), rejection and antifouling properties. The optimized of normalized flux (Jf /Jo) at different parameter in filtration (pH, ionic strength and tranmembrane-pressure) was carried out by using the response surface methodology (RSM). The results showed that the addition of 4 wt. % RHS give the highest flux at 300.50 L/m².hour (LMH). The highest rejection was found at 3 wt. % of RHS membrane with value 98% for UV254 and 96% for TOC. The optimal value of Jf/Jo was found at 0.62 with the condition of pH: 6.10, ionic strength: 0.05 mol/L and transmembrane-pressure: 2.67 bars. Optimize of RSM analysis from ANOVA also proved that the error of model is less than 0.05% which indicates that the model is significant.

scholarly journals Filterability of Polysulfone Membrane in a Tilted Panel System for Activated Sludge Filtration

Water ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 3533
Author(s):  
Ahmad Aliyan Alif Ismail ◽  
Sri Mulyati ◽  
Sri Aprilia ◽  
Mohd Hizami Mohd Yusoff ◽  
Normi Izati Mat Nawi ◽  
...  
Keyword(s):  
Activated Sludge ◽  
Pore Size ◽  
Membrane Fouling ◽  
Aeration Rate ◽  
Membrane Properties ◽  
Mean Flow ◽  
Clear Trend ◽  
Polysulfone Membrane ◽  
Tilting Angle ◽  
Filtration System

Membrane bioreactors (MBRs) are established technology for treatment of domestic and industrial wastewater because they offer a small footprint and high quality of effluent, in addition to lower excess sludge. However, their widespread applications are still limited by higher expenditure for compensating for membrane fouling. In this study, polysulfone (PSF)-based ultrafiltration membranes were developed and integrated with a tilted panel system for fouling control in activated sludge filtration. The results show an enhanced performance of filtration system thanks to the mutual advantage of the tilted panel system and the membrane properties. Both membranes showed a clear trend of higher permeability with respect to the tilted panel parameters, namely, higher tilting angle, higher aeration rate, and shorter intermittent/switching period. PSF-1 (1 wt% polyethylene glycol (PEG) additive) shows significantly better performance than PSF-3 (3 wt% PEG additive) although their mean flow pore size, structural properties, and contact angle do not differ significantly. PSF-1 shows superior filterability performance of about 45% for panel tilting angles of 20° at an aeration rate of 1.8 L·min−1, and 11% for a switching period of 1 min compared with PSF-3. The key property enhancing the performance of the PSF-1 is its narrower distribution of pore size. Overall results suggest that an optimum system could be achieved by optimizing both the filtration system and the membrane material properties.

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