چكيده به لاتين
In modem societies, one of the evaluadian criterion of the development is the energy consumption. The energy is the essential input in the field of industry and technology. Considering the growing demands for energy in the countries, as a result of technology development, the demand for fossil fuels has been grown. According to the limitations of fossil energy resources, and the importance of the alcohols as a fuel, researchers have started to investigate the fossil fuel/alcohol blends to increase the efficiency of such fuels and to decrease the amount of its pollutant. The present study is devoted to the experimental investigation of alcohol gasoline blends. Therefore, the effect of adding different alcohols on the gasoline characteristics of Imam Khomeini oil refinery ( Shazand, Arak) have been studied. After full analysis of the base gasoline specifications, ethanol with volumetric percentages of 10, 15, and 20 was mixed with gasoline, and different characteristics of the blended fuel such as density, research octane number (RON), motor octane number (MON)and Reid vapor pressure (RVP), closed cup flash point at atmospheric pressure, corrosion of copper blade, gross and net thermal value, distillation profile at atmosphere pressure, chromatography test, amount of water, amount of ash, and amount of sulfur have been investigated. Then, gasoline was mixed with the mentioned percentages by other alcohols including methanol, n-butanol, isobutanol, tert-butanol, and isopropanol. The research octane number (RON), motor octane number, and Reid vapor pressure have been measured for the blended fuels. It was found that the trend of RON for different gasoline/alcohol fuels was as follows: tert-butanol > isopropanol > methanol > ethanol. It was also found that RON was constant for isobutanol and it was decreased for n-butanol. The trend of MON for different gasoline/alcohol fuels was as follows: tert-butanol> isopropanol > ethanol > methanol > isobutanol > n-butanol. It was found that the addition of methanol and ethanol to gasoline leads to an increase in RVP. However, a derease in RVP is observed by addition of isobutanol and n-butanol. Besides, the RVP shows constant trend for tert butanol and isopropanol to 20 percent mixture and a decreasing trends was observed at this composition. Furthermore, by investigating the phase stability of the blended fuels, it was found that fuels containing methanol turned into two phases by decreasing temperature. For other alcohols, one phase was observed by decreasing temperature to -30 °C. In conclusion, it should be noted that tert-butanol, isopropanol, and ethanol can be added to the gasoline without any change. However, in other cases, binary or ternary mixture of alcohols should be provided in order to achieve suitable characteristics for the blended fuels.
Key words: ethanol, methanol, n-butanol, isobutanol, tert-butanol, isopropanol, Reid vapor pressure, octane number
