This study discusses a new finding for nanofiltration membrane development using phase inversion technique whereby polyethersulfone (PES) polymer was added with surfactant and additive. This research focuses on the development of a membrane that is efficient in treating oily wastewater and reducing membrane's low permeation flux issues. Five PES nanofiltration membranes were synthesized with pluronic F108 surfactant and different amounts of chitosan additive for each formulation. Subsequently, the effect of adding surfactant and additive on membrane performance was studied. Results showed that the membrane with the optimal amount of chitosan gave the highest flux and the rejection of oily wastewater with up to 90%. In addition, Fourier transform-infrared (FTIR) spectroscopy technique was used to characterize and analyse the membrane's properties. Hence, the developed membranes were successfully characterized and proved to be a good treatment for oily wastewater.

Nanofiltration is a membrane-based separation process that has been used widely in the separation and purification fields for various applications such as dye desalting, applications of water softening, pharmaceuticals and wastewater treatment. In this research, polyethersulfone (PES), polyethylene glycol (PEG), Pluronic F108 and silver nanoparticles (AgNPs) nanofiltration membrane was prepared using casting solution technique with N-methyl-2-pyrrolidone (NMP) was used as a solvent. The effects of Pluronic F108 and silver nanoparticles (AgNPs) concentrations in the casting solutions on the membrane performance/properties were also studied. The membrane pure water permeation (PWP) and salt rejection tests were carried out for membrane performance analysis. Scanning electron microscopy (SEM) was used for the membrane morphology characterization. Fourier transform infrared spectroscopy was utilized to identify functional groups in the membrane. Membrane with 2.0 wt.% of Pluronic F108 and 0.05 wt.% of AgNPs showed the best performances for both PWP (40.89 L/m2h) as well as permeation flux of salts solution of NaCl (43.95 L/m2h), Na2SO4 (21.16 L/m2h), MgCl2 (26.46 L/m2h) and MgSO4 (20.41 L/m2h). All fabricated membranes with different formulation of dope composition obtained high salts rejection in the range of 79% to 91%. SEM images showed addition of AgNPs has improved fabricated membrane morphology with higher pore density and larger macro-void structure.

This study reported on the preparation of newly low pressure active reverse osmosis (LPARO) membrane by phase inversion technique. The effect of cetyl trimethylammonium bromide (CTAB) and sodium dodecyl sulphate (SDS) as surfactants on performance and morphological structure were examined. Using brackish water as a sample, the membrane performance was evaluated in terms of pure water permeation (PWP), flux and salt rejection. Experimental data revealed that at 2.0 wt. % of SDS, the LPARO membrane achieved the optimum performance and produced the finest membrane. � 2016, Malaysian Society of Analytical Sciences. All rights reserved.

This research project was conducted to study the effects of irradiation on chitosan and its potential application as a plant growth promoter. Chitosan in the form of flakes was irradiated with gamma rays at irradiation dosage of 50 kGy, 100 kGy, 200 kGy and 400 kGy. The effect of irradiation on chitosan in terms of intrinsic viscosity and average molecular weight was measured using Ubbelohde capillary viscometry technique and the results obtained showed irradiation at doses of up to 50 kGy had caused an extremely significant reduction of both parameters and this trend continued at higher irradiation doses, although the decrease were not significant. The effect of various concentrations of chitosan and irradiated chitosan on growth promotion of Chinese kale (Brassica alboglabra) was hydroponically grown and cultivated for 50 days. Statistical analysis showed addition of 10 ppm of irradiated chitosan of 200 kGy and 400 kGy, respectively, resulted in an extremely significant increase in the percentage weight gain of Chinese kale (Brassica alboglabra). Results obtained in this study showed the potential use of irradiated chitosan as a plant growth promoter for plants grown hydroponically. � 2016 AIP Publishing LLC.

In this study, an asymmetric nanofiltration-surfactant (NFS) membrane was prepared via simple dry/wet phase inversion technique. A newly dope formulation consisting of different surfactants (SDS, CTAB) and polymer concentration (17 wt%-21 wt%) were developed. The effect of these parameters on dyes performance in terms of dyes flux, rejection and morphological structure were examined. Experimental data showed that, at different ranges of polymer concentration, NFS membranes shows low permeation flux of dyes ranging from 9.256 L/m2h to 14.315 L/m2h at 4 bar operating pressure. Significantly, the addition of SDS and CTAB surfactants were found to promote the increasing of dyes flux and rejection up to 79.698 L/m2h and 99.5% respectively. Addition of surfactant shows the membrane surface morphology with upper layer and support layer consists of finger-like structure, finger-like channel, macrovoids and spongy structure. � 2016, Malaysian Society of Analytical Sciences. All rights reserved.

Recently, dyes are generally used in various industries and release of these dyes into streams will pose a serious threat to the environment. In this research, a nanofiltration membrane was fabricated via phase inversion as it is one of the most convenient methods for membrane fabrication. It is used in removing dyes by using pluronic as a surfactant and chitosan as an additive. By varying the concentration of pluronic as a surfactant at 1 wt%, 2 wt%, and 3 wt%, and a constant amount of chitosan as an additive, three newly dope solutions were formulated. The fabricated membranes were analyzed by evaluating the membrane in terms of pure water permeation (PWP), permeation flux, salts rejection and dyes rejection. The introduction of pluronic as a surfactant and chitosan as an additive to the nanofiltration membrane produced high PWP and presented high salts rejection and dyes removal. Generally, high dyes rejections were achieved by M3 which contained high weight percentage (wt%) of pluronic as it showed highest percentage rejection for acid red, methyl blue and reactive black 5. The functional groups of the membranes were characterized and verified by using Fourier transform infrared spectroscopy (FTIR).

The role of surfactants in the formation of active Poly(vinylidene fluoride) (PVDF) ultrafiltration (AUF) membranes was studied. The effect combination of surfactants that are Sodium dodecyl sulfate (SDS)/Tween 80 and Tween 80/Triton X-100 formulations on performance and morphological structures were investigated for the first time. The influence of surfactants blends on the membrane pores was also examined. Experimental data showed that combination of Tween 80/Triton X-100 give the highest BSA permeation flux with a value of 285.51 Lm-2h-1. With combination of SDS/Tween 80, the AUF membrane showed the highest protein rejection up to 93% and 79% for Bovine Serum Albumin (BSA) and Egg Albumin (EA), respectively. Moreover, membranes characterization demonstrated that the addition of SDS/Tween 80 and Tween 80/Triton X-100 were found to affect the performance, surface morphologies and membrane pores of AUF PVDF membranes. � 2016, Malaysian Society of Analytical Sciences. All rights reserved.

The aim of this study was to establish a simple, accurate and reproducible method for the identification and quantification of surfactin using high-performance liquid chromatography (HPLC). Previously reported method of identification and quantification of surfactin were time consuming and requires a large quantity of mobile phase. The new method was achieved by application of Chromolith® high performance RP-18 (100 × 4.6 mm, 5 μm) as the stationary phase and optimization of mobile phase ratio and flow rate. Mobile phase consisted of acetonitrile (ACN) and 3.8 mM trifluroacetic acid (TFA) solution of 80:20 ratio at flow rate of 2.2 mL/min was obtained as the optimal conditions. Total elution time of the obtained surfactin peaks was four times quicker than various methods previously reported in the literature. The method described here allowed for fine separation of surfactin in standard sample (98% purity) and surfactin in fermentation broth.