International Journal of New Chemistry

151-155

Authors: Ehsan Darouneh; Tahereh Pirhooshyaran; Hashem Shalagheh

The objective of this research was the economic analysis of two different methods for the clarification of sugarcane juice. The first method was the method of using 700 ppm of CaO (final pH=7.9) and 1 ppm of Separan flocculant which previouly was being used. The other method was using 500 ppm of CaO (final pH=7.4) and 3 ppm of Separan flocculant. This study was carried out on an industrial scale in the Karoon sugar industry in south west of Iran. The results showed that increasing the amount of Separan and reducing the amount of lime directly increases the purification and the brix of the juice besides reducing the amount of lime precipitation in the evaporators. Economic analysis of the total process showed that the second method of clarification was 5 % more economical.

163-177

Authors: Asadollah Beiraghi; Ali Reza Shirkhani; Azim Ziyaei Halimehjani

In this study a cloud-point extraction process using non-ionic surfactant Triton X-114 for extraction of mercury (II) from aqueous solutions was developed. The method is based on the complex formation of Hg (II) with benzyl (pyridin-2-yl) methylcarbamodithioate at pH 5.5. After preconcentration and dilution of the surfactant-rich phase, the enriched analyte was determined by spectrophotometer. The effects of different parameters such as concentration of surfactant, electrolyte, temperature and pH on the cloud point extraction were studied in detail and a set of optimum conditions were established. Under the optimum conditions, the calibration graph was linear in the range of 0.25–3 µg mL-1 with detection limit of 0.02 µg mL-1. The precision (R.S.D. %) for 1 µg mL-1 of Hg (II) was 1.6% (n=5) and the preconcentration factor was found to be 20. Under the presence of foreign ions, no significant interference was observed. Finally, the proposed method was applied successfully for the determination of Hg (II) in real water samples.

190-197

Authors: Azita Salimian

Vanadium oxide nanotubes belong to inorganic nanotubes. One inorganic nanotubes (WS2) synthesized in 1992.Vanadium oxide nanotubes discovared by spahr in 1998.Vanadium oxide nanotubes are used in chemical, bio, electronics and catalysts industry. Many applications of these nanotubes have not yet been discovered. Especially when these nanotubes are doped with different elements. The structure of these nanotubes is flexible. This makes it possible to explore different ideas. In this research study zirconium – doped vanadium oxide nanotubes (VONTs) with different percentages were synthesized. Zr-doped VONTs were performed by hydrothermal method. Zr-VONTs prepared (0, 2, 10, 20, 30, 50 and 60) %wt. The structure and morphology of the nanotubes were investigated by x- ray diffraction (XRD), scanning electron microscopy (SEM). The results showed that zirconium 2%wt doped VONTs complately but in others amount in addition doped, was forming zirconium oxide phase. Also with increase percent of doping Zr into vanadium oxide nanotubes were formed monoclinic structure of ZrO2.The increase of doping level of the ZrO2 phase leads to change interlayer distances.