Conference on Membrane Science and Technology 2013 (MST 2013) The effect of SPEEK additive on polyethersulfonenanofiltration membrane for dye removal E. Halakoo,a,bR. Jamshidigohari,a,bA.F. Ismail,a,* W.J. Lau,a D. Emadzadeh,a,b A. Moslehyani,a a
Advanced Membrane Technology Research Center (AMTEC), UniversitiTeknologi Malaysia, 81310 Johor Bahru, Johor, Malaysia b
Department of Chemical Engineering, UniversitiTeknologi Malaysia, 81310 Johor Bahru, Johor, Malaysia *Corresponding author:
[email protected], Tel: 60-75535592, Fax: 60 – 75581463 Abstract The objective of this study is to investigate the effect of sulfonated poly (ether ether ketone) (SPEEK) content on the performance of polyethersulfone (PES) nanofiltration (NF) membrane for removal of dye compounds from a synthesized dyeing wastewater. Flat sheet nanofiltration (NF) membranes were prepared from 20 wt% PES and using variation of SPEEK content. The content of SPEEK, (0 – 2 wt%) was used as an additive in PES dope solution with the aim of producing PES NF membranes with negatively charged properties and higher hydrophilicity. The morphological structure of the membranes was determined using scanning electron microscopy (SEM) and their performances were examined in terms of flux and rejection. Results showed that the water flux of PES NF membrane is increased with increasing the SPEEK content, owing to the improvement in the hydrophilicity of membrane. The results were supported by the water contact angle values which also exhibited an increasing of values with increasing SPEEK content. With respect to dye removal, the charged NF membrane was able to efficiently remove the dye compound from synthesized dyeing wastewater. Rejection of about 99% was achieved thus producing good treated water which is suitable for water reuse. Keywords: Polyethersulfone, SPEEK, Nanofiltration membrane, Dye compound
1.0 INTRODUCTION Nowadays, the use of NF membrane can be found in many industries [1-3], such as chemical production [4], water and wastewater treatment, biotechnology [3], food processing [5], etc. Charged NF membranes have been the main domain of the research among membrane scientists and are widely used to improve solute retention and water permeability [6-7].Nanofiltration membranes are always made of aromatic polymers linked together either in a single chain or in a ladder or step-ladder arrangement, more elastic functional groups that are frequently set among the aromatic rings [8]. Sulfonation is an ordinary method to connect sulfonation group into the polymer organization which supported by characteristics of the sulfonating agent and the polymer base unit. Among the available polyelectrolytes, sulfonated poly(ether ether ketone), (SPEEK) is often chosen to provide negative charges to NF membrane due to its high thermal and mechanical stability, as well as good mixabilitywith many membrane forming polymers.The textile plant is one of the oldest and heaviest polluter in the world. In textile refining processes, substantial amount of water, mineral salts and reactive dyes are used. As a consequence, it generates a large amount of wastewater which contains complex contaminants from its daily operation.The best practical solution has been suggested by membrane method to meet the progressively severe discharge limits and to reclaim the textile wastewater by producing proper treated water. Dye retention, salt
rejection and COD retention are some examples of NF membrane usage in textile wastewater treatment [9]. Briefly, NF is an operative and efficient decontamination process for wastewater treatment process to remove impurities from the effluent discharged so that it can be safely discharged. The goal of this study was to develop hydrophilic PES nanofiltration membrane from high sulfonation degree of SPEEK and to investigate the effect of SPEEK additive on PES nanofiltration membrane for dye removal. Permeability and rejection rate of NF membranes in treating synthetic dyeing solution was studied. SEM images of the membranes also showed the effect of SPEEK additives. 2.0 EXPERIMENTAL 2.1 Materials Materials used in this study are as follows; PEEK in powder form (
