The effect of surfactants that are cationic (Cetyl trimethylammonium bromide (CTAB)), anionic (Sodium Dodecyl Sulphate (SDS)) and non-ionic (Triton X-100) on performance, morphologies and molecular orientation of Polysulfone (PSF) low pressure reverse osmosis (LPRO) membrane were addressed. The experimental data showed that the increasing of 0.5 wt% in surfactant concentration produced higher pure water permeation (PWP) and flux. At 2.5 wt% of SDS, the LPRO membranes achieved the highest PWP of about  64.42 L/m2 × h while 3.0 wt% of CTAB demonstrated the highest flux of 55.28 L/m2 × h. Analysis from morphological results foundthat the optimal performance at 89.6 % rejection was produced by the membrane with 2 wt% SDS which is a good promoter for the fine morphological structures of the membrane, thus producing fine spectrum of molecular orientation factor.

This paper addressed the pioneering work on the effects of dual surfactants component on the performance, morphologies and molecular properties of polyvinylidene fluoride/polyether glycol (PVDF/PEG 200) ultrafiltration (UF) membranes. The PVDF surfactant membranes were prepared via dry/wet via phase inversion technique with the addition of sodium dodecyl sulfate (SDS)/Tween 80 and Triton X-100/Tween 80 into polymer solution. Experimental data revealed that the dual surfactants improved the membrane performance up to 120.84 L/m2 × h and 82 % of permeate flux and rejection of bovine serum albumin, respectively. In addition, 2 wt% of dual surfactants alsofound to induce the growth of fine finger-like and macro-voids cavities inside the membranes while the FTIR spectra proved that the existence of dual surfactants in PVDF membranes produced better molecular alignment which contributed significantly towards better flux and good rejection. In conclusion, the used of dual surfactants in the PVDF ultrafiltration membranes improved the performance-properties of the membranes and extending the possibly versatile for the membrane to be used for more applications.

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Water shortage has become a real problem at global level and therefore, new and innovative technologies were established to provide sustainable solutions to water crisis. One of the effective approaches to resolve the global challenges is introducing the membrane-based desalination. Reverse Osmosis (RO) is a pressure driven membrane process which becoming increasingly popular and widely used for water purification applications that require high salt rejection such as brackish and seawater desalination. In this study, the influence of Sodium dodecyl sulphate (SDS) surfactant in producing the finest membrane for desalination were investigated in terms of performance, morphological structure and molecular orientation. From a polymer blending of polysulfone (PSF)/N-Methyl-2-Pyrrolidone (NMP)/polyvinylpyrrolidone (PVP)/sodium dodecyl sulphate (SDS) were formulated for making of low pressure reverse osmosis (LPRO) membrane. In order to examine the influence of SDS surfactant, different concentration from 0 wt% to 3 wt% were employed for desalination application of 10,000ppm (brackish water) and 50 000ppm (seawater). Experimental data showed that the increasing of 0.5wt% in surfactant produced higher pure water permeation (PWP) and flux. At 2.5wt% of SDS, the LPRO membranes showed the highest PWP of about 44.8L/m2h and brackish water flux at 45.58L/m2h. Meanwhile, at 3.0wt%, the highest flux of seawater at 39.37L/m2h was obtained. Moreover, the optimized LPRO (2wt% of SDS) membrane performed high rejection ratio of 90.9% for brackish water and 90.4% for seawater concentration of 10,000ppm and 50,000ppm, respectively. Therefore, the findings revealed that the fabricated LPRO membrane having a good potential to be used as eco-efficient desalination process of brackish water and seawater technology.