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Fatty alcohol is an important raw material for the production of surfactants, and is currently in demand by markets and has a high potential for growth. Moreover, fatty alcohol can be made from methylester that is produced from fats and natural oil. The production of fatty alcohol involved hydrogenation using the suspension method process and methyl ester in palm oil as the raw material. Copper chromite was used as the catalyst for the hydrogenationreaction and the experiment was proceeded in a close system pressure reaction vessel. The reaction was conducted at approximately 150-250oC, 1100-1700 psig, 2-8% catalyst W/V of methyl ester and reaction timefrom 5-20 hr. After the reaction, the products were analysed to check for percent conversion using gas chromatography (GC). The hydrogenation reaction began at 200oC. The best hydrogenation reaction for theproduction of fatty alcohol occurred at 250oC, 1700 psig, 6% catalyst and reaction time of 20 hr, which gave a purity greater than 97%.

The evaporations of volatile organic compounds (VOCs) from a simulated water basin with uniform temperature and concentration under mixed VOCs and unsteady wind conditions were studied experimentally to assess the validity of previously proposed mass transfer coefficient correlations for predicting the evaporation flux of VOC from a water basin. Two sets of VOC evaporation experiments were performed in a wind tunnel-water tank system. First, the evaporation fluxes of acetone and methyl ethyl ketone (MEK) were measured individually from the evaporation experiment of a mixture of acetone and MEK in water and compared with the values predicted by the two-film model. The results have shown that the mass transfer coefficient correlations obtained previously from evaporation of single VOC from water predict the evaporation rate of an individual VOC in mixture quite well. This indicated that the presence of a second VOC in the aqueous solution does not have any significant effect on the evaporation rate of the individual components possibly because their concentrations may be too dilute to exhibit any appraciable interaction. The second set of the experiments was the evaporation of acetone from water under unsteady wind speed with a windspeed range of 0-4.8 m.s-1. This study leads to a procedure for VOC evaporation determination under un steady wind condition using the mass transfer coefficient correlations proposed previously. The results have shown that the mass transfer coefficients based on the VOC evaporation from a water basin under steady wind conditions can actually be applied to predict the time-average volatilization flux under unsteady wind speed condition as well. The results from these two sets of the experiments suggest that the mass transfer coefficient correlations proposed previously could be applied to water basin with univorm temperature and concentration under mixed VOC and unsteady wind conditions.

Volatile organic compounds (VOCs) have been found in wastewater of many chemical industries. Evaporation of VOCs from open water basin in waste treatment facilities causes air-pollution and has been regulated in many countries. Reduction or prevention of VOCs evaporation from open water basin is then necessary. The aim of this research was to investigate the influence of surface film generated by an insoluble surfactant on the mass transfer coefficient of VOCs evaporating from water. Hexadecanol and octadecanol were used as surfactant in this investigation with the amount in the range of 0 to 35 μg/cm2 and 0 to 25 μg/cm2, respectively. The VOCs used in this study were methanol, acetone, methyl ethyl ketone and toluene. The experimental results showed that the surfactant film can reduce the gas film and liquid coefficients by 56 and 80 %, respectively. The suitable amounts of the surfactant were 25 μg/cm2 for hexadecanol and 15 μg/cm2 for octadecanol. From this investigation we can conclude that covering the water surface with a film of hexadecanol or octadecanol could significantly reduce the VOCs evaporation rate.Finally, the empirical equations correlating gas film and liquid film coefficient to amount of surfactants were developed and verified against the experimental data. The predicted values of the overall mass transfer coefficients, obtained by using these empirical equations, were in good agreement with the measured values. Thus the empirical equations of mass transfer coefficients developed in this work can be used to predict the evaporation rates of VOCs from water surface covered by hexadecanol or octadecanol film.

Stearin adulteration in refined palm oil crystallization was investigated for industrial separation of stearin and olein. The important standard properties of olein are the iodine value which must be higher than 55-57, and the cloud point which must be lower than 9ºC. The crystallization temperature is the most important parameter of the process to obtain the standard olein properties and should not exceed 20ºC. Longer crystallization time is possibly the cause of lower yields but higher quality. The stearin adulteration at the ratio of 1:9 leads to higher yields, but the quality of stearin adulteration shows unimportant effects. The uniformity of heat and mass transfer in the crystallization process are important factors in obtaining higher yields and quality of olein.

Methyl ester was produced from many sources of oil palm products, namely used frying oil, RBD palm oil, degummed and deacidified palm oil, palm stearin and superhard palm stearin. Production process was a conventional transesterification batch process using methanol as reactant and sodium hydroxide as catalyst. Production procedure consisted of oil preparation, solvent preparation, reaction step, glycerol separation, washing step and finishing step. Thin layer chromatograph was used to determine the composition of product and nearly 100% methyl ester was obtained at a suitable condition. Molar ratio of oil: methanol was about 1:6, which equal to 20% by weight of methanol. Sodium hydroxide was 0.5-1 %wt. of oil. The production temperature was 60-80ºC, mixing time was only 15-30 minutes and reaction time was 3-4 hours. Many fuel properties of methyl ester were very close to high-speed diesel such as viscosity, density, heating value and boiling point range. Pour point of methyl ester was higher than diesel owing to the high composition of saturated methyl ester that has a high melting point.

Recently, volatile organic compound (VOC) evaporation from open water basin such as an equalization basin in wasterwater treatment plant has been recognized as an important source of air polution. The amount of VOC evaporation from open water basin can be predicted by using the two-film theory that requires two mass transfer coefficients includint kG and kL. This paper studies the effect of wind speed over sater surface on the gas-film (kG) and the liquid-film (kL) mass transfer coefficient. A series of volatile organic compounds evaporation experiments were performed in a wind tunnel-water tank system in which the wind speed above the water surface can be easily controlled. The wind speeds were varied from 0 to 4.8 m/s. The water and the air temperature were constant at 25?1 and 28?1 OC, respectively.The kG and kL for various wind speeds were determined from unsteady state volatilization of methanol and toluene from water, respectively. The results indicated that kG increased lineraly with wind speed over the entire range while the relationship between kL and wind speed fell into two regimes with a break at the wind speed of 2.58 m/s. The mass transfer coefficient correlations (kG and kL) were developed from the experimental data and validated by comparing the predicted value of KOL, and the evaporation flux (Nvoc), which were predicted from kG and kL correlations, against the experimental data from evaporation of accetone and chloroform from water. The predicted value of KOL and NVOC provided good agreement with the experimental data.

A laboratory scale two-stage anaerobic process was studied in order to treat biodiesel wastewater. The first stage represented an acidogenic reactor while the second stage was a methanogenic reactor. The effect of nitrogen and phosphorus on the performance of both reactors was investigated. Biodiesel wastewater was adjusted so that its COD:N and COD:P within 100:0.1–1.1 and 100:0–1, respectively, and fed into the acidogenic reactor. After COD and pH adjustment, wastewater discharged from the acidogenic reactor was fed into the methanogenic reactor. The highest VFA concentration of 8.32 g/l was obtained from the acidogenic reactor at COD:N:P of 100:1.1:0.5. However, the highest CH4 yield of 0.170 l CH4 /g CODremoved was found at COD:N:P of 100:0.6:0.5 from the methanogenic reactor. Moreover, both nitrogen and phosphorus affected the acid composition produced in the acidogenic reactor and the long chain fatty acid consumption in the acidogenic and methanogenic reactors.