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Fatty acid methyl esters (FAMEs) are sustainable biofuel that can alleviate high oil cost and environmental impacts of petroleum-based fuel. A modified 1,200 W high efficiency fruit blender was employed for continuous transesterification of various refined vegetable oils and waste cooking oil (WCO) using sodium hydroxide as a homogeneous catalyst. The following factors have been investigated on their effects on FAME yield: baffles, reaction volume, total reactant flow rate, methanol-oil molar ratio, catalyst concentration and reaction temperature. Results indicated that the optimal conditions were: 2,000 mL reaction volume, 50 mL/min total flow rate, 1% and 1.25% catalyst concentration for refined palm oil and WCO, respectively, 6:1 methanol-to-oil molar ratio and 62 - 63oC, obtaining yield efficiency over 96.5% FAME yield of 21.14 ´ 10-4 g.J-1 (for palm oil) and 19.39 ´ 10-4 g.J-1 (for WCO). All the properties of produced FAMEs meet the EN 14214 and ASTM D6751 standards. The modified household fruit blender could be a practical and low-cost alternative biodiesel production apparatus for continuous biodiesel production for small communities in remote areas.

The amidoximated polymer gel for uranium recovery from natural seawater was successfully synthesized from radiation-polymerization and crosslinking of acrylonitrile (AN) and methacrylic acid (MAA) monomers with N,N’-Methylene bisacrylamide (MBA) as the crosslink agent. The optimum condition to prepare the polymer gel is: the gamma ray dose of 40 kGy, the AN:MAA ratio of 80:20, and the crosslink agent concentration of 8 g/L. The polymer gel can be reused for at least 8 times without significant performance decrease. The kinetic of seawater absorption by the adsorbent was quite rapid, reaching the equilibrium swelling ratio of approximately 250% in about 30 min. By submersion of this polymer gel in the seawater sample with only 300 and 840 ppb of added uranium for 4 weeks, the adsorption capacity reached as much as 6.96 and 9.64 mg/g, respectively. By submersion of this polymer gel in the seawater sample with 30 and 2140 ppm of added uranium for 1 week, the adsorption capacity reached as much as 334 and 409 mg/g, respectively. This high-efficiency amidoxime polymer gel offers a possibility of being utilized as a seawater uranium recovery agent on an industrial scale. Suitable elution conditions to minimize mass loss as well as suitable locations with clear seawater and no algae growth will need to be identified. Moreover, the research outcome presents a novel environmental remediation process to adsorb uranium ions released into seawater following a nuclear accident.

Enhancement of uranium extraction from seawater using chromic-acid-treated amidoxime adsorbent was studied. Chromic-acid-treated amidoxime fibers were synthesized based on the simultaneous irradiation grafting method at a low temperature. Low-density polyethylene (LDPE) fibers were treated with chromic acid for up to 90 minutes. After the treatment, the fibers were submerged in 60:40 acrylonitrile:methacrylic acid monomer by volume and irradiated with 40 kGy γ-ray. The maximum grafting efficiency of about 90% occurred at 20 minutes of acid treatment time, as a significant enhancement of 30% compared to the literature-reported value of about 70%. When submerged in shallow seawater with an average temperature of 30 °C for 4 weeks, the amidoxime adsorbent exhibited the adsorption capacity of 2.06 g-U/kg-adsorbent, which was 37% higher than the literature-reported value. These significantly increased grafting and adsorption efficiencies were attributed to the increased surface area of chromic-acid-etched LDPE...