Vol.:(0123456789) 1 3 Nanotechnology for Environmental Engineering (2021) 6:67 https://doi.org/10.1007/s41204-021-00161-w ORIGINAL PAPER Development of titanium dioxide incorporated ultrathin cellulose acetate membrane for enhanced forward osmosis performance Harshita Jain 1  · Renu Dhupper 1  · Anoop Kumar Verma 2  · Manoj Chandra Garg 1 Received: 2 January 2021 / Accepted: 26 September 2021 © The Author(s), under exclusive licence to Springer Nature Switzerland AG 2021 Abstract This study was conducted to develop ultrathin forward osmosis (FO) membrane by phase inversion process. Hydrophilic cellulose acetate (CA) polymer and titanium dioxide (TiO 2 ) nanoparticles were used to form a highly water permeable and stable FO membrane. The physical characteristics of prepared nanomaterial and membrane were characterized by scan- ning electron microscopy, elemental mapping and x-ray diffraction. The FO performance of the developed membrane was evaluated in terms of pure osmotic water flux and reverse salt flux. A consistent water flux was observed during a long-term experiment with the help of the fabricated membrane. Average water flux of 33.63 L/m 2 /h and reverse salt flux of 10.34 g/ m 2 /h were achieved due to extensive hydrogen bonding between cellulose ester and titania particles. The resultant membrane was found to be highly efficient in terms of FO performance and can be utilized for efficient desalinization of water. Keywords Fabrication · Forward osmosis · Membrane · Porous · Salt rejection Introduction One of the first things that humans worry about is the avail- ability of safe drinking water [1]. For this, two harmoni- ous applications are important to protect the water quality. Foremost is the establishment of laws by regulating bodies that establishes the basic standards to protect the minimum water quality for human consumption and uses. Second is the scientific and engineering world that provides the lat- est technological advances to achieve those standards [2]. The aim of water treatment systems is to provide drinking water from raw or untreated water. For this filtration is the lead requirement, which is an effective medium of remov- ing small particles, total dissolved solids and contaminants from water [3]. Different filtration methods are available, among which forward osmosis (FO) has attracted researches because of its dual advantages viz, technological advancement and less energy requirements [4, 5]. FO is a kind of osmotically driven filtration method in which a semi-permeable mem- brane is required to block the total dissolved solids and at the same time allow the passage of clean water [6]. The principle behind this method is the dilution of highly con- centrated draw side and at same time concentrating the feed side with consequent salt rejection by the membrane [7]. The main advantage of this method is that it does not require high energy and electricity like other membrane-based techniques [8, 9]. As it works under no hydraulic pressure, the fouling propensity is highly reduced allowing high water perme- ability and salt rejection. Regarding the membrane used in FO, any dense semi-per- meable material or substrate can be used; however it should give high osmotic water flux, low fouling, less internal con- centration polarization and high salt rejection [10, 11]. The conclusive requirement of FO process lies in the develop- ment of high flux membranes along with high salt rejection. * Manoj Chandra Garg mcgarg@amity.edu Harshita Jain harshita.jain3@student.amity.edu Renu Dhupper rdhupper@amity.edu Anoop Kumar Verma anoop.kumar@thapar.edu 1 Amity Institute of Environmental Sciences, Amity University Uttar Pradesh, Sector-125, Noida, Uttar Pradesh 201313, India 2 School of Energy and Environment, Thapar Institute of Engineering and Technology, Patiala, Punjab 147005, India