Current Advances in Biofouling Mitigation in Membranes for Water Treatment: An Overview

Membranes, as the primary tool in membrane separation techniques, tend to suffer external deposition of pollutants and microorganisms depending on the nature of the treating solutions. Such issues are well recognized as biofouling and is identified as the major drawback of pressure-driven membrane processes due to the influence of the separation performance of such membrane-based technologies. Herein, the aim of this review paper is to elucidate and discuss new insights on the ongoing development works at facing the biofouling phenomenon in membranes. This paper also provides an overview of the main strategies proposed by “membranologists” to improve the fouling resistance in membranes. Special attention has been paid to the fundamentals on membrane fouling as well as the relevant results in the framework of mitigating the issue. By analyzing the literature data and state-of-the-art, the concluding remarks and future trends in the field are given as well.

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Photocatalytic Membranes in Degradation of Organic Molecules

Materials Research Foundations - Photocatalysis ◽

10.21741/9781644901359-1 ◽

2021 ◽

pp. 1-56

Author(s):

G. Abdi

Keyword(s):

Wastewater Treatment ◽

Water Purification ◽

Membrane Fouling ◽

Membrane Separation ◽

Environmental Pollutants ◽

Heterogeneous Photocatalysis ◽

Pollutant Removal ◽

Separation Performance ◽

Membrane Fabrication ◽

Degradation Of Dyes

Heterogeneous photocatalysis is a technology widely applied to water puriﬁcation and wastewater treatment under ultraviolet (UV) or even sunlight irradiation for the removal of a variety of environmental pollutants into harmless species. Application of membrane for immobilization of semiconductors and their suitability in photocatalytic degradation of dyes have recently been developed. Integration of photocatalysis with membrane processes signiﬁcantly improve the membrane separation performance with reducing membrane fouling and improving permeate quality. This paper reviews recent progress in the photocatalytic membranes for wastewater treatment and water puriﬁcation with an emphasis on the type of membranes, membrane fabrication, and applications in pollutant removal.

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New Trends in Biopolymer-Based Membranes for Pervaporation

Molecules ◽

10.3390/molecules24193584 ◽

2019 ◽

Vol 24 (19) ◽

pp. 3584 ◽

Cited By ~ 17

Author(s):

Roberto Castro-Muñoz ◽

José González-Valdez

Keyword(s):

State Of The Art ◽

Future Trends ◽

Specific Production ◽

Fermentation Products ◽

Bacterial Fermentation ◽

Organic Mixtures ◽

Current State ◽

Production Processes ◽

Polybutylene Succinate ◽

Ongoing Development

Biopolymers are currently the most convenient alternative for replacing chemically synthetized polymers in membrane preparation. To date, several biopolymers have been proposed for such purpose, including the ones derived from animal (e.g., polybutylene succinate, polylactic acid, polyhydroxyalcanoates), vegetable sources (e.g., starch, cellulose-based polymers, alginate, polyisoprene), bacterial fermentation products (e.g., collagen, chitin, chitosan) and specific production processes (e.g., sericin). Particularly, these biopolymer-based membranes have been implemented into pervaporation (PV) technology, which assists in the selective separation of azeotropic water-organic, organic-water, organic-organic mixtures, and specific separations of chemical reactions. Thereby, the aim of the present review is to present the current state-of-the-art regarding the different concepts on preparing membranes for PV. Particular attention is paid to the most relevant insights in the field, highlighting the followed strategies by authors for such successful approaches. Finally, by reviewing the ongoing development works, the concluding remarks and future trends are addressed.

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Recent Progress in One- and Two-Dimensional Nanomaterial-Based Electro-Responsive Membranes: Versatile and Smart Applications from Fouling Mitigation to Tuning Mass Transport

Membranes ◽

10.3390/membranes11010005 ◽

2020 ◽

Vol 11 (1) ◽

pp. 5

Author(s):

Abayomi Babatunde Alayande ◽

Kunli Goh ◽

Moon Son ◽

Chang-Min Kim ◽

Kyu-Jung Chae ◽

...

Keyword(s):

Membrane Fouling ◽

Water Reuse ◽

Recent Progress ◽

Membrane Separation ◽

Separation Performance ◽

Two Dimensional ◽

Responsive Membranes ◽

Membrane Technologies ◽

Alternative Water ◽

Global Water

Membrane technologies are playing an ever-important role in the field of water treatment since water reuse and desalination were put in place as alternative water resources to alleviate the global water crisis. Recently, membranes are becoming more versatile and powerful with upgraded electroconductive capabilities, owing to the development of novel materials (e.g., carbon nanotubes and graphene) with dual properties for assembling into membranes and exerting electrochemical activities. Novel nanomaterial-based electrically responsive membranes have been employed with promising results for mitigating membrane fouling, enhancing membrane separation performance and self-cleaning ability, controlling membrane wettability, etc. In this article, recent progress in novel-nanomaterial-based electrically responsive membranes for application in the field of water purification are provided. Thereafter, several critical drawbacks and future outlooks are discussed.

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Separation of Biologically Active Compounds by Membrane Operations

Current Pharmaceutical Design ◽

10.2174/1381612822666161027153823 ◽

2017 ◽

Vol 23 (2) ◽

pp. 218-230 ◽

Cited By ~ 4

Author(s):

Xiaoying Zhu ◽

Renbi Bai

Keyword(s):

Energy Consumption ◽

Bioactive Compounds ◽

Membrane Fouling ◽

Membrane Separation ◽

Separation Efficiency ◽

High Energy ◽

Separation Processes ◽

Membrane Processes ◽

Separation Technology ◽

Pressure Driven

Background: Bioactive compounds from various natural sources have been attracting more and more attention, owing to their broad diversity of functionalities and availabilities. However, many of the bioactive compounds often exist at an extremely low concentration in a mixture so that massive harvesting is needed to obtain sufficient amounts for their practical usage. Thus, effective fractionation or separation technologies are essential for the screening and production of the bioactive compound products. The applicatons of conventional processes such as extraction, distillation and lyophilisation, etc. may be tedious, have high energy consumption or cause denature or degradation of the bioactive compounds. Membrane separation processes operate at ambient temperature, without the need for heating and therefore with less energy consumption. The “cold” separation technology also prevents the possible degradation of the bioactive compounds. The separation process is mainly physical and both fractions (permeate and retentate) of the membrane processes may be recovered. Thus, using membrane separation technology is a promising approach to concentrate and separate bioactive compounds. Methods: A comprehensive survey of membrane operations used for the separation of bioactive compounds is conducted. The available and established membrane separation processes are introduced and reviewed. Results: The most frequently used membrane processes are the pressure driven ones, including microfiltration (MF), ultrafiltration (UF) and nanofiltration (NF). They are applied either individually as a single sieve or in combination as an integrated membrane array to meet the different requirements in the separation of bioactive compounds. Other new membrane processes with multiple functions have also been developed and employed for the separation or fractionation of bioactive compounds. The hybrid electrodialysis (ED)-UF membrane process, for example has been used to provide a solution for the separation of biomolecules with similar molecular weights but different surface electrical properties. In contrast, the affinity membrane technology is shown to have the advantages of increasing the separation efficiency at low operational pressures through selectively adsorbing bioactive compounds during the filtration process. Conclusion: Individual membranes or membrane arrays are effectively used to separate bioactive compounds or achieve multiple fractionation of them with different molecule weights or sizes. Pressure driven membrane processes are highly efficient and widely used. Membrane fouling, especially irreversible organic and biological fouling, is the inevitable problem. Multifunctional membranes and affinity membranes provide the possibility of effectively separating bioactive compounds that are similar in sizes but different in other physical and chemical properties. Surface modification methods are of great potential to increase membrane separation efficiency as well as reduce the problem of membrane fouling. Developing membranes and optimizing the operational parameters specifically for the applications of separation of various bioactive compounds should be taken as an important part of ongoing or future membrane research in this field.

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PET Radiochemistry Automation: State of the Art and Future Trends in 18F-nucleophilic Fluorination

Current Organic Chemistry ◽

10.2174/13852728113179990102 ◽

2013 ◽

Vol 17 (19) ◽

pp. 2097-2107 ◽

Cited By ~ 18

Author(s):

Raisa Krasikova

Keyword(s):

State Of The Art ◽

Future Trends ◽

Nucleophilic Fluorination

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Application of Microextraction-Based Techniques for Screening-Controlled Drugs in Forensic Context—A Review

Molecules ◽

10.3390/molecules26082168 ◽

2021 ◽

Vol 26 (8) ◽

pp. 2168

Author(s):

Samir M. Ahmad ◽

Oriana C. Gonçalves ◽

Mariana N. Oliveira ◽

Nuno R. Neng ◽

José M. F. Nogueira

Keyword(s):

Environmental Sustainability ◽

Illicit Drugs ◽

State Of The Art ◽

Cost Benefit ◽

Future Trends ◽

Present Contribution ◽

Controlled Drugs ◽

Related Compounds ◽

Innovative Techniques ◽

Great Simplicity

The analysis of controlled drugs in forensic matrices, i.e., urine, blood, plasma, saliva, and hair, is one of the current hot topics in the clinical and toxicological context. The use of microextraction-based approaches has gained considerable notoriety, mainly due to the great simplicity, cost-benefit, and environmental sustainability. For this reason, the application of these innovative techniques has become more relevant than ever in programs for monitoring priority substances such as the main illicit drugs, e.g., opioids, stimulants, cannabinoids, hallucinogens, dissociative drugs, and related compounds. The present contribution aims to make a comprehensive review on the state-of-the art advantages and future trends on the application of microextraction-based techniques for screening-controlled drugs in the forensic context.

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Effect of Pre-Oxidation on Coagulation/Ceramic Membrane Treatment of Yangtze River Water

Membranes ◽

10.3390/membranes11050369 ◽

2021 ◽

Vol 11 (5) ◽

pp. 369

Author(s):

Shengji Xia ◽

Xinran Zhang ◽

Yuanchen Zhao ◽

Fibor J. Tan ◽

Pan Li ◽

...

Keyword(s):

Water Treatment ◽

Membrane Fouling ◽

Membrane Filtration ◽

Ceramic Membrane ◽

Membrane Separation ◽

Membrane System ◽

Coagulation System ◽

Fouling Control ◽

Filtration System ◽

Membrane Treatment

The membrane separation process is being widely used in water treatment. It is very important to control membrane fouling in the process of water treatment. This study was conducted to evaluate the efficiency of a pre-oxidation-coagulation flat ceramic membrane filtration process using different oxidant types and dosages in water treatment and membrane fouling control. The results showed that under suitable concentration conditions, the effect on membrane fouling control of a NaClO pre-oxidation combined with a coagulation/ceramic membrane system was better than that of an O3 system. The oxidation process changed the structure of pollutants, reduced the pollution load and enhanced the coagulation process in a pre-oxidation-coagulation system as well. The influence of the oxidant on the filtration system was related to its oxidizability and other characteristics. NaClO and O3 performed more efficiently than KMnO4. NaClO was more conducive to the removal of DOC, and O3 was more conducive to the removal of UV254.

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