Molecular Dynamics Study of Carbon Nanotubes/Polyamide Reverse Osmosis Membranes: Polymerization, Structure, and Hydration.

Carbon nanotubes/polyamide (PA) nanocomposite thin films have become very attractive as reverse osmosis (RO) membranes. In this work, we used molecular dynamics to simulate the influence of single walled carbon nanotubes (SWCNTs) in the polyamide molecular structure as a model case of a carbon nanotubes/polyamide nanocomposite RO membrane. It was found that the addition of SWCNTs decreases the pore size of the composite membrane and increases the Na and Cl ion rejection. Analysis of the radial distribution function of water confined in the pores of the membranes shows that SWCNT+PA nanocomposite membranes also exhibit smaller clusters of water molecules within the membrane, thus suggesting a dense membrane structure (SWCNT+PA composite membranes were 3.9% denser than bare PA). The results provide new insights into the fabrication of novel membranes reinforced with tubular structures for enhanced desalination performance.

[1]  Huajian Gao,et al.  A cohesive law for carbon nanotube/polymer interfaces based on the van der Waals force , 2006 .

[2]  E. Drioli,et al.  MEMBRANE DISTILLATION , 2012 .

[3]  I. E. Ary,et al.  Interfacially synthesized reverse osmosis membrane and processes for their preparation , 1992 .

[4]  Benoît Roux,et al.  Computer simulations of water flux and salt permeability of the reverse osmosis FT-30 aromatic polyamide membrane , 2011 .

[5]  J. G. Powles,et al.  Computer-simulation of osmosis and reverse-osmosis in solutions , 1994 .

[6]  V. Freger,et al.  Does hindered transport theory apply to desalination membranes? , 2014, Environmental Science and Technology.

[7]  Peter G. Kusalik,et al.  The Spatial Structure in Liquid Water , 1994, Science.

[8]  Benoît Roux,et al.  Molecular dynamics study of a polymeric reverse osmosis membrane. , 2009, The journal of physical chemistry. B.

[9]  David Cohen-Tanugi,et al.  Mechanical strength of nanoporous graphene as a desalination membrane. , 2014, Nano letters.

[10]  Fawzi Banat,et al.  Solar thermal desalination technologies , 2008 .

[11]  M. Kazemimoghadam Preparation of nanopore HS zeolite membranes for reverse osmosis processes , 2011 .

[12]  Michael Kotelyanskii,et al.  Molecular dynamics simulation study of the mechanisms of water diffusion in a hydrated, amorphous polyamide , 1999 .

[13]  Jong‐Chan Lee,et al.  High-performance reverse osmosis CNT/polyamide nanocomposite membrane by controlled interfacial interactions. , 2014, ACS applied materials & interfaces.

[14]  S. L. Mayo,et al.  DREIDING: A generic force field for molecular simulations , 1990 .

[15]  M. Hoang,et al.  Synchrotron SAXS to probe cross-linked network of polyamide ‘reverse osmosis’ and ‘nanofiltration’ membranes , 2012 .

[16]  M. Elimelech,et al.  The Future of Seawater Desalination: Energy, Technology, and the Environment , 2011, Science.

[17]  B. Bruggen,et al.  Preparation and characterization of thin-film nanocomposite membranes embedded with poly(methyl methacrylate) hydrophobic modified multiwalled carbon nanotubes by interfacial polymerization , 2013 .

[18]  J. Georgiadis,et al.  Science and technology for water purification in the coming decades , 2008, Nature.

[19]  Noreddine Ghaffour,et al.  Water Desalination using geothermal energy , 2010 .

[20]  Vesselin Kolev,et al.  Hydration, porosity and water dynamics in the polyamide layer of reverse osmosis membranes: A molecular dynamics study , 2014 .

[21]  Michael Kotelyanskii,et al.  Atomistic simulation of water and salt transport in the reverse osmosis membrane FT-30 , 1998 .

[22]  Benny D. Freeman,et al.  Reverse osmosis desalination: water sources, technology, and today's challenges. , 2009, Water research.

[23]  H. Strathmann,et al.  Polymer-water interaction and its relation to reverse osmosis desalination efficiency☆ , 1977 .

[24]  Xiaohong Shao,et al.  Zwitterion functionalized carbon nanotube/polyamide nanocomposite membranes for water desalination. , 2013, ACS nano.

[25]  J. I. Siepmann,et al.  A method for the direct calculation of chemical potentials for dense chain systems , 1990 .

[26]  M. Terrones,et al.  High-performance multi-functional reverse osmosis membranes obtained by carbon nanotube·polyamide nanocomposite , 2015, Scientific Reports.

[27]  D. Morineau,et al.  Liquids in confined geometry: How to connect changes in the structure factor to modifications of local order , 2003 .

[28]  Il Juhn Roh,et al.  Investigation of the specific role of chemical structure on the material and permeation properties of ultrathin aromatic polyamides , 2002 .

[29]  K. Gubbins,et al.  Fast method for computing pore size distributions of model materials. , 2006, Langmuir : the ACS journal of surfaces and colloids.

[30]  C. K. Kim,et al.  Effects of the polyamide molecular structure on the performance of reverse osmosis membranes , 1998 .

[31]  J. Tersoff,et al.  Modeling solid-state chemistry: Interatomic potentials for multicomponent systems. , 1989, Physical review. B, Condensed matter.

[32]  Ilian T. Todorov,et al.  A short description of DL_POLY , 2006 .

[33]  Yaolin Liu,et al.  Molecular dynamics simulations of polyamide membrane, calcium alginate gel, and their interactions in aqueous solution. , 2014, Langmuir : the ACS journal of surfaces and colloids.

[34]  X. Gong,et al.  A charge-driven molecular water pump. , 2007, Nature nanotechnology.

[35]  David Cohen-Tanugi,et al.  Water permeability of nanoporous graphene at realistic pressures for reverse osmosis desalination. , 2014, The Journal of chemical physics.

[36]  Xiao-bo Zhu,et al.  Electrochemical mineral scale prevention and removal on electrically conducting carbon nanotube--polyamide reverse osmosis membranes. , 2014, Environmental science. Processes & impacts.

[37]  Jong-Gyu Kim,et al.  The changes of membrane performance with polyamide molecular structure in the reverse osmosis process , 2000 .

[38]  S. Joo,et al.  Separation of a heavy metal from water through a membrane containing boron nitride nanotubes: molecular dynamics simulations , 2014, Journal of Molecular Modeling.

[39]  Bobby G. Sumpter,et al.  Tunable water desalination across graphene oxide framework membranes. , 2014, Physical chemistry chemical physics : PCCP.

[40]  Y. Cho,et al.  Experimental evidence of rapid water transport through carbon nanotubes embedded in polymeric desalination membranes. , 2014, Small.

[41]  Armand Soldera,et al.  Structure and dynamics of water confined in a polyamide reverse-osmosis membrane: A molecular-simulation study , 2014 .

[42]  Neil M. Wade,et al.  Distillation plant development and cost update , 2001 .

[43]  Araz Jakalian,et al.  Fast, efficient generation of high‐quality atomic charges. AM1‐BCC model: I. Method , 2000 .

[44]  Junwoo Park,et al.  Enhancement of chlorine resistance in carbon nanotube-based nanocomposite reverse osmosis membranes , 2010 .

[45]  I. Pinnau,et al.  Preparation and water desalination properties of POSS-polyamide nanocomposite reverse osmosis membranes , 2015 .

[46]  Menachem Elimelech,et al.  Covalent binding of single-walled carbon nanotubes to polyamide membranes for antimicrobial surface properties. , 2011, ACS applied materials & interfaces.

[47]  Desalination using geothermal energy , 2016 .

[48]  Jean-Paul Ryckaert,et al.  On the convergence of the SHAKE algorithm , 1991 .