Recent Developments in Nanomaterials-Modified Membranes for Improved Membrane Distillation Performance

Abstract

<jats:p>Membrane distillation (MD) is a thermally induced membrane separation process that utilizes vapor pressure variance to permeate the more volatile constituent, typically water as vapor, across a hydrophobic membrane and rejects the less volatile components of the feed. Permeate flux decline, membrane fouling, and wetting are some serious challenges faced in MD operations. Thus, in recent years, various studies have been carried out on the modification of these MD membranes by incorporating nanomaterials to overcome these challenges and significantly improve the performance of these membranes. This review provides a comprehensive evaluation of the incorporation of new generation nanomaterials such as quantum dots, metalloids and metal oxide-based nanoparticles, metal organic frameworks (MOFs), and carbon-based nanomaterials in the MD membrane. The desired characteristics of the membrane for MD operations, such as a higher liquid entry pressure (LEPw), permeability, porosity, hydrophobicity, chemical stability, thermal conductivity, and mechanical strength, have been thoroughly discussed. Additionally, methodologies adopted for the incorporation of nanomaterials in these membranes, including surface grafting, plasma polymerization, interfacial polymerization, dip coating, and the efficacy of these modified membranes in various MD operations along with their applications are addressed. Further, the current challenges in modifying MD membranes using nanomaterials along with prominent future aspects have been systematically elaborated.</jats:p>

Recent Improvement Strategies on Metal-Organic Frameworks as Adsorbent, Catalyst, and Membrane for Wastewater Treatment

“…Various methods have been extensively employed for the POPs removal in wastewater such as flocculation/coagulation [6], adsorption [5,7], photocatalytic [8,9], Fenton-like catalysts [10,11], membrane separation [12,13], and reverse osmosis [14]. Among these methods, adsorption, catalytic degradation, and membrane separation are promising techniques for eliminating harmful pollutants from wastewater due to their low cost and simple process [13,15,16].…”

Stability of Ar/O2 Plasma-Treated Polypropylene Membranes Applied for Membrane Distillation

“…As has been indicated by Yao et al [4], key factors influencing fouling and wetting in the MD process are classified as: membrane surface properties, process parameters and feed characteristics. An increasing number of studies have found that reducing of the fouling intensity can be achieved by various methods of modifying the surface properties of the membranes [13][14][15][16][17][18][19]. For example, it has been demonstrated [20,21] that fouling caused by hydrophobic compounds present in the feed can be successfully limited by improving the membrane's surface hydrophilicity.…”

An Improved Modelling Approach for the Comprehensive Study of Direct Contact Membrane Distillation

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