الفهرس 
CHAPTER IOnly 14 pages are availabe for public view
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Abstract
All-hydrocarbon-base gasoline (BG) was formulated volumetrically from three local refinery streams, namely, reformate, isomerate and light naphtha produced by Cairo Refining Petroleum Company-Mostorod Refinery. This BG was volumetrically formulated from reformate (70%), isomerate (20%) and light naphtha (10%). Three sets of oxygenated gasoline fuels, were prepared by blending the hydrocarbon base stock with 2.0, 4.0, 6.0 and 8.0 volume % of each of ethyl acetate, iso- butyl acetate and n-butyl acetate. The performance and characteristics of the twelve prepared gasoline ester fuel blends, were examined and compared with that of hydrocarbon- base reference fuel. Also, the impact of concentration and type of ester-oxygenate, were studied.
For ester-free and ester-blended gasoline fuels, ASTM distillation tests were performed and distillation profiles were constructed to determine the distillation characteristics which represent front-end, mid-range and tail-end volatilities. Other volatility criteria values comprise: vapour pressure, temperature for vapour/liquid ratio of 20 (TV/L=20), vapour lock index (VLI), and driveability index (DI), were determined. Also, the formulated gasoline fuel blends, were tested for octane number, oxidation stability, calorific value and corrosivity.
Tailpipe exhaust emission experiments were conducted on a four cylinders, four-stroke spark ignition engine type 1.4 sahin car, and model 2001. The engine has a swept volume of 1400 C.C. and compression ratio of 8.3/1, using KANE portable gas analyzer at Tabbin Institute for Metallurgical Studies (MIMS).
The obtained results revealed that all levels of ester addition tend to lower the boiling temperature slightly after the front-end volatility region. Addition of 8.0 vol.% ester, increases the octane number of hydrocarbon- base gasoline 1.3, 2.0 and 2.6 for n-butyl-, iso-butyl-, and ethyl acetates, respectively. The contribution of these ester-oxygenates in octane number, is satisfactory if compared with that achieved by ether- and alcohol- oxygenates. Addition of the investigated esters resulted in a linear decrease in the calorific value of the obtained fuel blends. In oxidation stability test, the determined induct periods of all the investigated gasoline-ester blends, equate the safe storage time specified in Egypt (i.e. 480 minutes).
Increasing ester concentration from 2.0 to 8.0 vol.%, decreased the driveability index (DI) of the obtained fuel blends. However DI values remain within the normal range (850-1300) which permits good driveability performance for vehicles fueled with these fuel blends. Within the concentration range of added esters, the vapour pressure of gasoline-ethyl acetate blend is higher than that of gasoline-iso-butyl acetate one. Gasoline-n-butyl acetate showed irregular change in vapour pressure.