11 research outputs found
Process Optimization for Ethyl Ester Production in Fixed Bed Reactor Using Calcium Oxide Impregnated Palm Shell Activated Carbon (CaO/PSAC)
: The continuous production of ethyl ester was studied by using a steady-state fixed bed reactor (FBR). Transesterification of palm stearin (PS) and waste cooking palm oil (WCPO) with ethanol in the presence of calcium oxide impregnated palm shell activated carbon (CaO/PSAC) solid catalyst was investigated. This work was determined the optimum conditions for the production of ethyl ester from PS and WCPO in order to obtain fatty acid ethyl ester (FAEE) with the highest yield. The effects of reaction variables such as residence time, ethanol/oil molar ratio, reaction temperature, catalyst bed height and reusability of catalyst in a reactor system on the yield of biodiesel were considered. The optimum conditions were the residence time 2-3 h, ethanol/oil molar ratio 16-20, reaction temperature at 800C, and catalyst bed height 300 mm which yielded 89.46% and 83.32% of the PS and WCPO conversion, respectively. CaO/PSAC could be used repeatedly for 4 times without any activation treatment and no obvious activity loss was observed. It has potential for industrial application in the transesterification of triglyceride (TG). The fuel properties of biodiesel were determined
Correlated conformation and charge transport in multiwall carbon nanotube - conducting polymer nanocomposites
The strikingly different charge transport behaviors in nanocomposites of
multiwall carbon nanotubes (MWNTs) and conducting polymer polyethylene
dioxythiophene - polystyrene sulfonic acid (PEDOT-PSS) at low temperatures are
explained by probing their conformational properties using small angle X-ray
scattering (SAXS). The SAXS studies indicate assembly of elongated PEDOT-PSS
globules on the walls of nanotubes, coating them partially thereby limiting the
interaction between the nanotubes in the polymer matrix. This results in a
charge transport governed mainly by small polarons in the conducting polymer
despite the presence of metallic MWNTs. At T > 4 K, hopping of the charge
carriers following 1D-VRH is evident which also gives rise to a positive
magnetoresistance (MR) with an enhanced localization length (~ 5 nm) due to the
presence of MWNTs. However, at T < 4 K, the observation of an unconventional
positive temperature coefficient of resistivity (TCR) is attributed to small
polaron tunnelling. The exceptionally large negative MR observed in this
temperature regime is conjectured to be due to the presence of quasi-1D MWNTs
that can aid in lowering the tunnelling barrier across the nanotube - polymer
boundary resulting in large delocalization.Comment: Accepted J. Phys.: Condens. Matte
Process Optimization for Ethyl Ester Production in Fixed Bed Reactor Using Calcium Oxide Impregnated Palm Shell Activated Carbon (CaO/PSAC)
The continuous production of ethyl ester was studied by using a steady-state fixed bed reactor (FBR). Transesterification of palm stearin (PS) and waste cooking palm oil (WCPO) with ethanol in the presence of calcium oxide impregnated palm shell activated carbon (CaO/PSAC) solid catalyst was investigated. This work was determined the optimum conditions for the production of ethyl ester from PS and WCPO in order to obtain fatty acid ethyl ester (FAEE) with the highest yield. The effects of reaction variables such as residence time, ethanol/oil molar ratio, reaction temperature, catalyst bed height and reusability of catalyst in a reactor system on the yield of biodiesel were considered. The optimum conditions were the residence time 2-3 h, ethanol/oil molar ratio 16-20, reaction temperature at 800C, and catalyst bed height 300 mm which yielded 89.46% and 83.32% of the PS and WCPO conversion, respectively. CaO/PSAC could be used repeatedly for 4 times without any activation treatment and no obvious activity loss was observed. It has potential for industrial application in the transesterification of triglyceride (TG). The fuel properties of biodiesel were determine