Improving the performance of polyamide Nano-filtration membrane in acidic media by incorporation of modified multi-walled carbon nanotubes

Postprint (author's final draft

Recent advancements in the application of new monomers and membrane modification techniques for the fabrication of thin film composite membranes: A review

Thin film composite (TFC) membranes have been experiencing significant modifications recently aiming to improve their structure, properties and separation efficiency. One of the promising modifications to tailor the membranes more efficient is changing the materials used. m-phenylene diamine (MPD), piperazine (PIP), and trimesoyl chloride (TMC) are the most common monomers used to fabricate TFC membranes. Recent studies have introduced several alternatives to these traditional monomers showing significant contribution of these monomers to the physicochemical properties of the membranes (e.g., surface roughness, hydrophilicity, cross-linking density, chemical structure) as well as membranes\u27 separation efficiency. Emergence of more favorable functional groups such as carboxylic and amine groups due to the new materials integration facilitates the polymerization process and is beneficial to the membrane properties. Here, a critical review on the new interfacial polymerization monomers applied for reverse osmosis (RO) and nanofiltration (NF) membranes fabrication is presented. The membrane molecular structure and fabrication mechanism are investigated in details. This is followed by a review of the recent surface modification methods including grafting, coating and additive incorporating into the thin layer of membranes. The application of alternative monomers to MPD, PIP and TMC are investigated and the benefits of using these monomers or co-monomers are discussed

A Study for Water Purification Using Reverse Osmosis Membrane Modified with Carbon Nanotube

Water desalination systems is among the methods used to produce potable water to be used for domestic, agricultural and industrial applications.  Reverse osmosis is a common methods  employed for desalination facilities, mainly because of its low energy consumption, and high efficiency for permeate production. The main aim of this research is to use nanocomposite containing carbon nanotubes to improve membrane wall performance. in addition, the increase in the flux as a result of decreased clogging surface on the membrane was also studied.  To accomplish the objective of the study, the synthesized polyamid reverse osmosis nanocomposite membrane were used for purification of brackish water with the characteristic of having the electroconductivity of 4000 µs/cm. The modified raw-multi walled carbon nanotubes membrane was embedded through polymerization method in order to increase porosities and hydrophilicity. Analysis of Contact angle, SEM, FTIR and AFM were done for recognizing the compounds which were created on the surface of membranes and membranes hydrophilicity. Three sets of samples were prepared for testing in the membrane cell synthesis analysis. Water flux and rejection rates were assessed every 30 minutes. Results of this study showed that the membranes have soft hydrophil surfaces and by increasing nanocomposite concentrations with specified measure, the water flux increased up to 30.8 L/m2h which was noticeable compared to the simple polyamide membranes. Our results also showed that fouling reduced considerably and the clogging condition was reduced by nanocomposite membranes, and the rejection rate was higher than 97 percent for all synthesized membranes with pyrrol