Contents lists available at ScienceDirect Chemical Engineering & Processing: Process Intensification journal homepage: www.elsevier.com/locate/cep Anti-biofouling of 2-acrylamido-2-methylpropane sulfonic acid grafted cellulose acetate membranes used for water desalination Mahmoud Shaban a , El Sayed H. El Ashry a , H. Abdel-Hamid a , Ashraf Morsy b,c, *, Sherif Kandil b a Department of Chemistry, Faculty of Science, Alexandria University, Egypt b Materials Science Department, Institute of Graduate Studies & Research, Alexandria, Egypt c Department of Chemistry, Egyptian Petrochemicals Company, Alexandria, Egypt ARTICLE INFO Keywords: Cellulose acetate 2-Acrylamide-2-methylpropane sulfonic acid Protein adsorption Membrane Anti-biofouling ABSTRACT Cellulose acetate based membranes are used for water desalination. Cellulose diacetate (CDA) was prepared from cellulose powder. Reverse osmosis (RO) membranes were prepared on polyester sheets using CDA based through phase inversion technique. The structural, morphological and hydrophilic properties of the prepared membranes were characterized by Fourier transform infrared spectroscopy (FTIR), Nuclear magnetic resonance (NMR), scanning electron microscopy (SEM), and contact angle measurements. The FTIR and NMR revealed the presence of the carbonyl groups and degree of substitution (DS) in CDA. Modified membranes by Grafted to improve the performance and the anti-biofouling properties of cellulose acetate reverse osmosis (RO) membranes. The anti- biofouling properties were studied by measurements of static protein adsorption. The effect of grafting the membrane on the salt rejection and water flux was studied using a cross flow RO unit. The results indicated that 15 wt% of 2-acrylamido-2-methylpropanesulfonic acid (AMPS)Grafted membranes have lower adsorption of protein and microbes, in addition to increased salt rejection to 99.24 % and water flux to 17.12 l/m 2 h. 1. Introduction Reverse osmosis (RO) has been developed as a practical separation technology since the symmetric cellulose acetate RO membrane was developed by Loeb and Sourirajan in 1960 [1]. The top dense layer governs the permeation properties of the asymmetric membrane, the porous sub-layer only provides the membrane with mechanical strength [2]. Currently, the mainstream of RO membrane transport theory is the solution–diffusion model. According to the model, mass transfer occurs in three steps: absorption to the membrane, diffusion through the membrane, and desorption from the membrane. The chemical potential gradient from the feed side of the membrane to the permeate side of the membrane is the driving force for the mass transfer. When the differ- ence in hydrostatic pressure is greater than the difference in osmotic pressure between the upstream and downstream sides of the mem- brane,a chemical potential difference of water across the membrane drives water against the natural direction of water flow. Pressure-driven membrane processes, particularly ultrafiltration (UF), are separation techniques that are currently utilized in biotechnology,food processing, and pharmaceutical industry [3,4] A number of materials were tested as candidate materials for RO membranes, but still CA membranes are widely popular [5]. The separation process by membrane is essentially both the surface chem- istry and morphology of the membrane play a crucial role in de- termining the membrane performance. Therefore, it is a natural con- sequence to modify membrane surface for reducing the fouling and increase membrane surface hydrophilicity by surface modification techniques [4]. The main emphases of the developed RO membranes have been directed at improvements of RO performance, namely high salt rejection and permeate flux [6]. However, biofouling resulting from the attachment of microorganism communities to the membrane sur- face is the major obstacle for the widespread application of membrane technology [7]. The biofouling adds filtration resistance and increases the operational costs because of the need for frequent cleaning and maintenance [8,9]. The use of biocides and cleaning protocols for biofouling control may be reduced by membranes resistant to bio- fouling. Smooth surfaces have historically shown resistance to protein and bacterial adhesion. CA membranes offer several advantages as they are relatively easy to make and they have excellent mechanical prop- erties. They are also relatively more resistant to attack by chlorine. Composed to other membranes such as those based on aromatic poly- amides [10]. The enhanced surface hydrophilicity of the membranes results in the improvement of their antifouling performance. There are many surface modification techniques for the membrane surface such as https://doi.org/10.1016/j.cep.2020.107857 Received 10 September 2019; Received in revised form 12 January 2020; Accepted 10 February 2020 ⁎ Corresponding author at: Materials Science Department, Institute of Graduate Studies & Research, Alexandria, Egypt. E-mail address: drashrafm8@gmail.com (A. Morsy). Chemical Engineering & Processing: Process Intensification 149 (2020) 107857 Available online 11 February 2020 0255-2701/ © 2020 Elsevier B.V. All rights reserved. T