International Journal of New Chemistry

83-90

Authors: Ehsan Darouneh; Mahmood Zargan

Abstract In this study the wastewater treatment of a gas refinery was investigated by using an aerobic trickle bed filter bioreactor. Using a methanothrophic bacterium was the only difference of this experiment from the common aerobic wastewater treatment processes. In addition to reach the standards of wastewater treatments the other goal of using this special bacterium was the production of a bacterial biomass which can be used as a biofertilizer. The optimization of major effective parameters such as inoculum size, ammonium sulfate, sodium hydrogen phosphate and methanol concentration and hydraulic and retention time was carried out by using the simple experiment design method of one variable at the time in a trickle bed bioreactor. The results of this study showed that the maximum biofertilizer production of 0.45 g/lit was obtainable in the optimum conditions including inoculum size of 0.27g/lit, ammonium sulfate concentrations of 0.25g/lit, sodium hydrogen phosphate concentration of 0.1g/lit, methanol concentration of 0.1g/lit, hydraulic time of 1.6 minutes and retention time of 24 hours.

103-112

Authors: Maryam Negar Saberiyan Sani; Mohammad Hussein Sayadi Anari

Nanotechnology could be a very important field of recent research dealing with medical, industrial, environment. Silver nanoparticles are the topics of researchers because of their distinctive properties (size, shape depending optical, antimicrobial, and electrical properties). The synthesis of safe nanoparticles by biological organisms is recommended due to the environmental friendliness and low costs compared to physical and chemical methods. Recently, researchers tend to use a biological synthesis of nanoparticles by biological methods such as plants. This research aimed to study on the rainfall level on the biosynthesis of silver nanoparticles by Lamiaceae family plants in different regions of Iran. T-test student was used to examining the relationship between the size of nanoparticles and rainfall, using spss version 22 software. The study shows phenol concentration in low rainfall areas is more than high rainfall area, which is the main factor for the synthesis of nanoparticles. The result of the study demonstrated that the highest size of synthesized nanoparticle is 50 nm and the lowest size 10 nm, which are related to high rainfall and low rainfall regions respectively. The results showed the relationship between synthetic nanoparticles sizes and rainfall are significant p-value

124-139

Authors: Asadollah Beiraghi; Mina Roshdi

In the present study a cloud-point extraction process using non-ionic surfactant Triton X-114 for selective extraction of gallium from aqueous solutions was developed. The method is based on the complex formation of Ga (III) with N, N′ -bis (salycilidene)-1, 2-phenylenediamine (salophen) as a chelating agent in buffer media of pH 5. After phase separation and dilution of the surfactant-rich phase with 0.2 mL of a (80-20) propanol-water mixture containing 0.02 mL HNO3, the enriched analyte was determined by inductively coupled plasma-atomic emission spectrometry (ICP-AES). The variables affecting the complexation and extraction steps were optimized. Under the optimum conditions (i.e. 7.5×10-5 mol L-1 salophen, 0.5% (v/v) Triton X-114, 45ºC equilibrium temperature, incubation time 15 min) the calibration graph was linear in the range of 20–120 ng mL-1 with detection limit of 1.5 ng mL-1. The precision (R.S.D. %) for five replicate determinations at 60 ng mL-1 of Ga (III) was better than 4%. In this manner, the preconcentration factor was 22.2. Under the presence of foreign ions, no significant interference was observed. Finally, the proposed method was utilized successfully for the determination of gallium in water and rice samples.