Coconut dregs, soya dregs and lala clam shells have been used as low cost sorbents for the removal of heavy metals from aqueous solution. The effect of pH, contact time, initial metal concentration and temperature on sorption process was studied in batch experiments. Results of the equilibrium experiments showed that the solution pH was the key factor affecting the sorption characteristics. The kinetics data were best described by pseudo-second order, while the equilibrium data were best fitted by Langmuir isotherm. The thermodynamic studies indicated that the sorption is spontaneous and endothermic. Desorption studies showed that heavy metals are retained on the sorbents' surface following interaction with eluents. FTIR analysis confirmed that 0- and N-containing functional groups are the main sorption sites in coconut dregs and soya dregs. The presence of calcium carbonate in lala clam shells favours ion exchange mechanism. Based on effectiveness study using industrial wastewater, it.....

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In the present study, the feasibility of amphiphilic chitosan derivatives, namely oleoyl carboxymethyl chitosan (OCMCs), N,N-dimethylhexadecyl carboxymethyl chitosan (DCMCs) and deoxycholic acid carboxymethyl chitosan (DACMCs) as carrier agents for rotenone in water-insoluble pesticide formulations was investigated. Fourier Transform Infrared (FTIR) Spectrometer, CHN-O Elemental Analyser (CHN-O) and Transmission Electron Microscope (TEM) were used to characterise amphiphilic chitosan derivatives. The critical micelle concentration (CMC) of amphiphilic chitosan derivatives was determined using a Fluorescence Spectrometer. A High Performance Liquid Chromatography (HPLC) was used to determine the ability of OCMCs, DCMCs and DACMCs to load and release rotenone in an in vitro system. Based on TEM analysis, results have shown that amphiphilic chitosan derivatives formed self-assembly and exhibited spherical shape. The CMC values determined for OCMCs, DCMCs and DACMCs were 0.093, 0.098 and 0......

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This study investigates the potential of N-octyl chitosan derivatives, namely N-octyl-O-sulfate chitosan (NOOSC), N-octyl-N-succinyl chitosan (NONSC) and N-octyl-O-glycol chitosan (NOOGC) as amphiphilic carrier agents for atrazine in water-insoluble herbicide formulations. The N-octyl chitosan derivatives were characterised using several analytical instruments such as Fourier Transform Infrared (FTIR) Spectrometer, CHNS-O Elemental Analyser (CHNS-O), Transmission Electron Microscope (TEM), Thermogravimetric Analyser (TGA), Differential Scanning Calorimeter (DSC) and Fluorescence Spectrometer. The encapsulation of atrazine by N-octyl chitosan derivatives was studied using a High Performance Liquid Chromatography (HPLC). The FTIR spectra of N-octyl chitosan derivatives confirmed the presence of hydrophobic and hydrophilic groups on chitosan backbone. TEM images revealed that N-octyl chitosan derivatives have formed self-aggregates with a spherical shape. The CMC values for N-octyl chitos.....

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In the present study, gelatin–carboxymethyl cellulose blend film was synthesized, characterized and applied for the first time to preserve cherry tomatoes (Solanum lycopersicum var. cerasiforme) and grapes (Vitis vinifera). Gelatin (Gel) film forming solution was incorporated with carboxymethyl cellulose (CMC) at three volume per volume (Gel:CMC) ratios, namely 75:25, 50:50 and 25:75. CMC treatment has improved the transparency, tensile strength (TS), elongation at break (EAB), water vapor permeability and oxygen permeability of gelatin films. A pronounced effect was obtained for 25Gel:75CMC film. The TS and EAB values were increased from 25.98 MPa and 2.34% (100Gel:0CMC) to 37.54 MPa and 4.41% (25Gel:75CMC), respectively. A significant improvement in antimicrobial property of gelatin films against two food pathogens, namely Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) was obtained in the presence of CMC. The effectiveness of gelatin–CMC blend films to extend th.....

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In this study, gelatin-chitosan (Gel-Cs) blend films were prepared at three volume per volume ratios (Gel:Cs) namely 75:25, 50:50 and 25:75. The gelatin-chitosan blend films were applied for the first time to preserve cherry tomatoes (Solanum lycopersicum) and grapes (Vitis vinifera) in a 14- day preservation study. The addition of chitosan has improved the transparency value, tensile strength, percentage elongation at break, water vapour, oxygen permeability and antimicrobial properties of gelatin film. Of blended films studied, 25Gel:75Cs film exhibited the best functional and mechanical properties. The tensile strength and elongation at break values of 25Gel:75Cs film showed a significant increased by 26% and 63%, respectively. The presence of chitosan has enhanced the ability of gelatin film to inhibit two common food pathogenic microorganisms, namely Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). Results from preservation study suggest that the gelatinchitosan b.....

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Development of low-cost, sustainable and environmentally friendly biodiesel is a key focus in the energy industry worldwide. It is known that selecting suitable raw feedstock materials and optimising an efcient transesterifcation process are crucial in biodiesel production. Efective and realistic strategies are imperative in order to boost the quantity and quality of biodiesel production. In fact, scientists and researchers have put great efort to improve the market value of their biodiesel products. In recent years, the feasibilities of several raw materials as feedstocks to produce biodiesel have been assessed by researchers.These materials were reported able to produce biodiesel that met international standards, namely  the American Society for Test and Materials D6751 and European Standard 14214. Although these biodiesel products have met the quality criteria, their fatty acid methyl ester (FAME) contents difer. This review focuses on optimum conditions (methanol/oil molar ratio, .....

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