Vol. 1 Issue 1 Jan.-Mar. 2010

year 2010

P. Boonnoun, C. Muangnapoh, P. Prasitchoke, V. Tantayakom and A. Shotipruk

Abstract: This study deals with the development of a novel carbon based catalyst for use in reactive extraction, to separate 1,3-PDO from a model solution of the fermentation broth. The catalyst was synthesized by incomplete carbonization of naphthalene, in sulfuric acid at 523 K. The surface area and pore volume of the catalyst were found to be 1.1 m2 g-1 and 0.07 cm3 g-1, respectively. The acidity of the catalyst was 1.46 mmol/g. The test of the catalyst for the acetalization of acetaldehyde and 1,3-PDO in an aqueous solution indicated its applicability for such a reaction. The optimal quantity of the catalyst required for this reaction was 0.7 g/ g 1,3-PDO, giving a conversion of approximately 92%, after 2 h of reaction at 35°C. In addition to acetalization reaction, a reactive extraction was also carried out, using ethyl-benzene as an extractant. At 40 g/L of initial 1, 3-PDO solution, a typical concentration of 1, 3-PDO was derived from the fermentation process, the conversion was found to be 78.92% after 60 min for a reactive extraction at 35°C. The results of this study thus confirm the potential application of the lower cost carbon-based catalyst to replace the expensive polymeric ion exchange resins, for 1,3-PDO reactive extraction.

Key words: 1,3-propanediol, fermentation broth, separation, solvent extraction.

M. Zhang*, H. Mu and Y. Ning

Abstract: Because the transportation sector consumes more and more energy, it is important to predict future transport energy demand for sustainable transport. In this paper, a new method PLSRGM (0, N) is proposed by integrating PLSR (partial least square regression) into GM (0, N). Then TEDM (transport energy demand model) based on PLSRGM(0,N) will be activated using GDP, population, urban per capita disposal, rural per capita net income, passenger-kilometers and freight ton-kilometers with historical energy data available from 1997 to 2006. The results of posteriori checks show that the model is more reliable and has higher forecasting accuracy. The projections are made with two scenarios until 2030. It is expected that this paper will provide an effective tool to develop energy model that will greatly assist policy-makers.

Keywords: Transport energy demand; Socio-economic indictors; PLSRGM (0, N).

M. Abdullah*, Khairurrijal, F.A. Noor, A.R. Marully and M. Sanny

Abstract: A catalyst of CuO/ZnO/Al2O3 has been synthesized using the simple heating of a nitrates precursor in a polymer solution. A steam reforming reactor for converting methanol into hydrogen using an ultrasonic nebulizer as a liquid feeder and the prepared catalyst was also be designed. The produced catalyst particles had relatively small sizes (ranging from about 70 – 120 nm) and were softly agglomerated. Testing of the conversion reacting performance showed the presence of the starting temperature for methanol to hydrogen conversion to be 300oC, above which the conversion occurred and below which the conversion disappeared. These two works (synthesis of catalyst and design of reactor) are promising developments of direct methanol fuels cells to be used in automobiles technology.

Keywords: steam reforming methanol reactor, direct methanol fuel cell, catalyst.

M.K. Ahmad*, M.L.M. Halid, N.A.Rasheid, A.Z. Ahmed, S. Abdullah and M. Rusop

Abstract:The effects of annealing temperatures on the surface morphology and the electrical properties of titanium dioxide (TiO2) thin films prepared by the sol-gel method were studied. TiO2 thin films were deposited on silicon substrates using the spin coater technique. By varying the parameters of the annealing temperatures, The TiO2 thin films were deposited onto silicon substrates. Characterization was done using current-voltage (I-V) measurement and scanning electron microscopy (SEM). TiO2 thin films were annealed at 300°C, 350°C, 400°C, 450°C and 500°C. The result indicated that the electrical properties of the TiO2 thin films were changed with the increasing of the annealing temperature. As the annealing temperature increased, the resistivity decreased. The SEM investigation showed that the grain size of the TiO2 increased with higher annealing temperatures. The results showed that surface porosity, electrical properties and surface morphology of TiO2 could be affected by changing the annealing temperature.

Keywords: Titanium Dioxide Thin Film; Sol Gel Method; Electrical Properties.

S. Yavinchan*, R.H.B. Exell and D. Sukawat

Abstract: Numerical weather predictions have been made to evaluate selected convective parameterization schemes in forecasts of typical heavy rainfall events in Thailand. The Betts-Miller (BM), Grell (GR), Kain-Fritsch (KF), and new Kain-Fritsch (KF2) schemes were used in the Penn State/NCAR non-hydrostatic mesoscale model (MM5) with grid resolutions of 45 km and 15 km. The examples studied were in four important convective conditions, namely days with heavy rain in the hot season (NE region), the cold season (S region), the rainy season (E region), and a tropical depression (NE region).
Total rain patterns from the models were compared qualitatively with rain patterns derived from records at rain gauge stations, and with cloud patterns derived from geostationary meteorological satellite infrared images. Quantitative evaluation was obtained by calculating the bias and the Peirce skill score in small study areas with heavy rain as a function of accumulated rainfall over thresholds in the range zero to 80 mm every 12 h up to 48 h.
The four convective parameterization schemes gave widely different results. In the hot season case, none of the schemes predicted the rainfall well. In the other cases, the GR scheme was usually the best. The new KF2 scheme usually gave better results than the original KF scheme, indicating a potential for improvement in this scheme. The BM scheme was less successful than the other schemes.

Keywords: Numerical weather prediction; tropical precipitation; MM5; Betts-Miller; Grell; Kain-Fritsch; forecast verification.

S. Ummartyotin, S. Sangngern, A. Kaewvilai, N. Koonsaeng, H. Manuspiya and A. Laobuthee*

Abstract: Cobalt aluminate (CoAl2O4) was successfully prepared through a Co-Al-TEA complex. The possible structure of the Co-Al-TEA complex determined by FTIR and MS was proposed as a trimetallic species consisting of one TEA group per metal center. The bluish-violet powders of CoAl2O4 generated by calcination at different temperatures ranging from 600 to 1200°C for 2 h in air were investigated by XRD, SEM and BET. The CoAl2O4 pellets sintered at 1300°C at different times were preliminarily studied for their dielectric property as a function of frequency (1 kHz – 1 MHz) at ambient temperature.

Keywords: Co-Al-TEA complex, CoAl2O4, dielectric property.