Read by QxMD icon Read


Linh Duy Nguyen, Sana Gassara, Minh Quang Bui, François Zaviska, Philippe Sistat, André Deratani
The shortage of drinking water is a major problem in the rural areas of the Mekong Delta, especially, when surface water, a main local direct drinking water source is being threatened by pesticide pollution and salinity intrusion. A hybrid process coupling electrodialysis (ED) and nanofiltration (NF) is proposed as an effective process easy to setup in a small plant to treat complex matrix with high salinity and pesticide concentration as is the Mekong Delta surface water. Performance of the ED-NF integration was evaluated with synthetic solutions based on the comparison with a single NF step generally used for pesticide removal...
December 13, 2018: Environmental Science and Pollution Research International
Goji Y Shangkum, Patchanee Chammingkwan, Dai X Trinh, Toshiaki Taniike
Deposition of UiO-66 metal⁻organic framework nanoparticles onto a porous polymer support is a promising approach to designing highly-permeable, size-selective, flexible, and stable membranes for water filtration. In this article, a series of UiO-66 nanoparticles having different particle sizes were synthesized and employed to prepare UiO-66-deposited composite membranes. It was found that the size of the UiO-66 nanoparticles had great influences on the performance of the composite membranes for the filtration of a methylene blue aqueous solution...
December 12, 2018: Membranes
Haiguang Zhang, Xie Quan, Xinfei Fan, Gang Yi, Shuo Chen, Hongtao Yu, Yongsheng Chen
Nanofiltration (NF) is considered a promising candidate for brackish and sea water desalination. NF exhibits high multivalent ion rejection, but the rejection rate for monovalent ions is relatively low. Besides, great challenges remain for conventional NF membranes to achieve high ion rejection without sacrificing water flux. This work presents an effective strategy for improving the ion rejection of conductive NF membrane without decreasing the permeability through electrically-assisted enhancement of surface charge density...
December 12, 2018: Environmental Science & Technology
Xuechen Zhou, Yang-Ying Zhao, Sang-Ryoung Kim, Menachem Elimelech, Shu Hu, Jae-Hong Kim
Enhancing the chemical and physical properties of the polyamide active layer of thin-film composite (TFC) membranes by surface coating is a goal long-pursued. Atomic layer deposition (ALD) has been proposed as an innovative approach to deposit chemically robust metal oxides onto membrane surfaces due to its unique capability to control coating conformality and thickness with atomic scale precision. This study examined the potential to coat the surface of TFC reverse osmosis (RO) and nanofiltration (NF) membranes via ALD of TiO2 ...
December 5, 2018: Environmental Science & Technology
Lianpei Zou, Sitong Zhang, Jianyong Liu, Yi Cao, Guangren Qian, Yu-You Li, Zhi Ping Xu
A commercial nanofiltration (NF) membrane was modified using poly(sodium 4-styrenesulfonate) (PSS) to improve the nitrate rejection from groundwater. Fourier transform infrared spectroscopy, thermogravimetric analysis, zeta potential, and water contact angle analyses were performed, showing that PSS was successfully coated onto the membrane with the surface negative charge density being enhanced. The results of nitrate removal tests showed that the best PSS concentration was 1.5 mg/L, with the nitrate rejection rate of 88...
December 4, 2018: Environmental Science and Pollution Research International
Lifang Chen, Xiaokai Bian, Xiaofeng Lu
The performance of different nanofiltration (NF) membranes for the treatment of strontium-containing radioactive wastewater was investigated. The effects of the initial strontium concentration, solution pH and complexation phenomena on strontium removal were described. For all the three membranes, the strontium rejection increased with decreasing initial strontium concentration. Meanwhile, the strontium rejection was minimum at the membrane isoelectric point (pH 5) primarily due to decreased co-ion electrostatic repulsion...
November 2018: Water Science and Technology: a Journal of the International Association on Water Pollution Research
Hyun-Kyung Woo, Juhee Park, Ja Yoon Ku, Chan Ho Lee, Vijaya Sunkara, Hong Koo Ha, Yoon-Kyoung Cho
Androgen-receptor splice variant 7 (AR-V7) is associated with castration-resistant prostate cancer (CRPC) and resistance to anti-androgen therapy. Despite its clinical importance, the lack of efficient methods for AR-V7 analysis remains a challenge for broader use of this biomarker in routine clinical practice. Herein, we suggest a practical and non-invasive liquid biopsy method for analysis of AR-V7 in the RNA of urine-derived extracellular vesicles (EVs) without the need for blood withdrawal. Urine-derived EVs were isolated by a lab-on-a-disc integrated with six independent nanofiltration units (Exo-Hexa) allowing simultaneous processing of six individual samples...
November 30, 2018: Lab on a Chip
Dongsheng Zhao, Chang Su, Guicai Liu, Youbing Zhu, Zhengyang Gu
In this study, the long-term operational performance of an on-site NF facility at a full-scale oil-field wastewater desalination plant was monitored. The NF facility with poor permeability due to membrane fouling enables efficient multivalent salt removal (rejections of Mg2+ , Ca2+ , Fe3+ , and Al3+ were approximately 100%). Moreover, a comparison of the cleaning efficiencies of two on-site cleaning modes indicated that PL-007 cleaning helped to improve the effectiveness of subsequent acid cleaning in the removal of inorganic foulants...
November 27, 2018: Environmental Science and Pollution Research International
Antónia Macedo, Joana Monteiro, Elizabeth Duarte
The amount of cheese whey generated from the production of speciality sheep and goat cheese is significantly growing due to the acclaimed nutritional and medicinal benefits of the milk from these species. However, most of the cheese whey generated has no applications, thus giving rise to environmental problems. This work focuses on the study of the performance of the nanofiltration process for recovering the permeates of ultrafiltration from sheep and goat cheese whey. Nanofiltration experiments were carried out with membranes of nanofiltration (NF) in total recirculation and concentration modes, at 25 °C...
November 20, 2018: Membranes
Xiao Wang, Palitha Jayaweera, Radwan A Alrasheed, Saad A Aljlil, Yousef M Alyousef, Mohammad Alsubaei, Hamad AlRomaih, Indira Jayaweera
High-performance polybenzimidazole (PBI) hollow-fiber membranes (HFMs) were fabricated through a continuous dry-jet wet spinning process at SRI International. By adjusting the spinning air gap from 4″ (10.2 cm) to 0.5″ (1.3 cm), the HFM pore sizes were enlarged dramatically without any significant change of the fiber dimensional size and barrier layer thickness. When fabricated with an air gap of 2.5″ (6.4 cm) and a surface modified by NaClO solution, the PBI HFM performance was comparable to that of a commercial reverse osmosis (RO) HFM product from Toyobo in terms of salt (NaCl) rejection and water permeability...
November 19, 2018: Membranes
Sang Hee Park, Yeojin Kim, Soon Jin Kwon, Min Gyu Shin, Seung Eun Nam, Young Hoon Cho, You In Park, Jeong F Kim, Jung-Hyun Lee
Organic solvent nanofiltration (OSN) has made significant advances recently, and it is now possible to fabricate thin film composite (TFC) membranes with a selective layer thickness below 10 nm that gives ultrafast solvent permeance. However, such high permeance is inadvertently limited by the support membrane beneath the selective layer, and thus there is an urgent need to develop a suitable support to maximize TFC performance. In this work, we employed a commercially available polyethylene (PE) battery separator as a porous support to fabricate high performance TFC OSN membranes...
November 21, 2018: ACS Applied Materials & Interfaces
Qisong Xu, Kang Zhang, Jianwen Jiang
The need to understand and describe permeation through membranes has driven the development of many well-established transport models. The modelling parameters such as solubility, diffusivity and permeability represent the intrinsic nature of molecular interactions between membrane and permeants. In this study, we report a simulation and analysis methodology for liquid permeation. Based on a single simulation of liquid sorption process into a membrane, the solubility and diffusivity are estimated simultaneously, then the permeability is predicted by the solution-diffusion model...
November 21, 2018: Journal of Physical Chemistry. B
Stefan Beisl, Sílvia Monteiro, Ricardo Santos, Ana Sofia Figueiredo, María Guadalupe Sánchez-Loredo, Maria Amélia Lemos, Francisco Lemos, Miguel Minhalma, Maria Norberta de Pinho
The present work addresses the synthesis of nanofiltration composite membranes with bactericide properties. The cellulose acetate based membranes with polyvinylpyrrolidone coated silver nanoparticles, silver ion-exchanged β-zeolite and β-zeolite are casted by the phase inversion technique and subjected to an annealing post-treatment. They are characterized in terms of the nanofiltration permeation performance and antibacterial properties. The incorporation of silver nanoparticles produces a threefold increase in the membrane hydraulic permeability when compared to the silver-free membranes and the incorporation of silver ion loaded zeolite resulted in a 56...
November 5, 2018: Water Research
Önder Tekinalp, Sacide Alsoy Altinkaya
The aim of this study is to prepare high flux, stable, antifouling nanofiltration membranes through single bilayer polyelectrolyte deposition. To this end, a tight ultrafiltration support membrane was prepared from a polysulfone/sulfonated polyethersulfone blend. Deposition of a polyethyleneimine and alginate pair on this support has reduced the molecular weight cut off from 6 kDa to below 1 kDa. The pure water permeability and polyethylene glycol 1000 rejection of the coated membrane were found to be 15...
October 29, 2018: Journal of Colloid and Interface Science
Bingbing Yuan, Chi Jiang, Pengfei Li, Honghong Sun, Peng Li, Tao Yuan, Haixiang Sun, Qingshan Jason Niu
Poly(piperazine-amide)-based nanofiltration membranes exhibit a smooth surface and superior antifouling properties, but often have lower Ca2+ and Mg2+ rejection due to their larger inner micropore, and thus cannot be extensively used in water softening applications. To decrease the pore size of poly(piperazine-amide) membranes, we designed and synthesized a novel monomer, 1,2,3,4-cyclobutane tetracarboxylic acid chloride (BTC), which possesses a smaller molecular conformation than trimesoyl chloride (TMC). The thickness of the prepared BTC-piperazine (PIP) polyamide nanofilm via interfacial polymerization is as thin as 15 nm, significantly lower than the 50 nm thickness of the TMC-PIP nanofilm...
November 12, 2018: ACS Applied Materials & Interfaces
Zhenzhen Zhang, Md Mushfequr Rahman, Clarissa Abetz, Barbara Bajer, Jiali Wang, Volker Abetz
Isoporous integral asymmetric membranes derived from the self-assembly of block copolymers combined with the non-solvent-induced phase separation (SNIPS) have gained great attention. To extend their utility, good control over pore size and surface functionality in a facile manner is highly desirable. Here, an approach is proposed to achieve this by quaternization of the poly(4-vinylpyridine) moiety of a polystyrene-block-poly(4-vinylpyridine) SNIPS membrane using alkyl iodides via a scalable gas-solid heterogeneous reaction...
November 12, 2018: Macromolecular Rapid Communications
Michele Galizia, Kelly P Bye
The vast majority of industrial chemical synthesis occurs in organic solution. Solute concentration and solvent recovery consume ~50% of the energy required to produce chemicals and pose problems that are as relevant as the synthesis process itself. Separation and purification processes often involve a phase change and, as such, they are highly energy-intensive. However, novel, energy-efficient technologies based on polymer membranes are emerging as a viable alternative to thermal processes. Despite organic solvent nanofiltration (OSN) could revolutionize the chemical, petrochemical, food and pharmaceutical industry, its development is still in its infancy for two reasons: (i) the lack of fundamental knowledge of elemental transport phenomena in OSN membranes, and (ii) the instability of traditional polymer materials in chemically challenging environments...
2018: Frontiers in Chemistry
Isaac Owusu-Agyeman, Michael Reinwald, Azam Jeihanipour, Andrea Iris Schäfer
In the context of decentralised brackish water treatment in development applications, the influence of water quality on membrane separation was investigated with real waters. High ionic strength (low net driving pressure) on fluoride (F) retention by nanofiltration (NF) and reverse osmosis (RO) was investigated over a wide pH range (2-12). Further, the influence of pH on the permeation of natural organic matter (NOM) fractions, in particular low molecular weight (LMW) neutrals, was elucidated. Natural and semi-natural waters from Tanzania with similar F concentrations of about 50 mg L-1 but varying NOM and inorganic carbon (IC) concentration were filtered with an NF and RO, namely NF270 and BW30...
October 19, 2018: Chemosphere
Xu Xie, Jordan M Dennison, Jungwoo Shin, Zhu Diao, David G Cahill
We developed an optical pump-probe technique, frequency-domain probe beam deflection (FD-PBD) to measure the diffusion of water vapor in nanoscale polymer films with microsecond temporal resolution and micrometer spatial resolution. We describe the quantitative model of beam deflection for multilayer structures, the experimental approach, and the application of FD-PBD to measure the diffusivity ( D m ) of saturated water vapor in various glassy polymer films including polyimide (PI, D m = 7.0 × 10-13 m2 s-1 ), poly(methyl methacrylate) (PMMA, D m = 1...
October 2018: Review of Scientific Instruments
Lihua Lan, Xianwang Kong, Haoxiang Sun, Changwei Li, Dezhao Liu
Swine wastewater treatment plant has become one of the main sources of antibiotic resistance genes (ARGs). Membrane treatment processes are promising solutions for removal of the emerging contaminants. However, limited studies have investigated the effects of nanofiltration and reverse osmosis treatment in removing ARGs in swine wastewater. In this study, the presence and the fate of common ARGs including sul1, sul2, tetA, tetM and tetW, as well as intI1 and 16S rRNA gene, were investigated in a medium-sized (6500) pig farm wastewater treatment plant (WWTP) equipped with conventional biological treatment and advanced membrane processing system...
October 24, 2018: Journal of Environmental Management
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"