الفهرس 
I. INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Biodiesel is a cleaner burning fuel than diesel and a suitable replacement. It is made from non-toxic, biodegradable, renewable resources, such as new and used cooking oil, and animal fats. Oils chemically react with alcohols (methanol was used in this study) to produce chemical compound known as fatty acid methyl esters (biodiesel). Glycerol, used in the pharmaceutical and cosmetics industry along with many other applications after purification process, is produced in this reaction as by-product.
The relative high cost of refined oils, fats and production methods makes biodiesel more expensive than petroleum-derived fuel.
So preliminary studies was done using the waste cooking oils as feed stocks for biodiesel production. As the free fatty acids in used cooking oils was higher than 1 mg /g KOH which obstacle the production by soap formation, two step production process was studied. Esterification process was studied using various affecting parameters on the reaction. Alcohol to oil molar ratio, catalyst amount, reaction temperature, mixing intensity, catalyst type and alcohol type was varied, and the highest free fatty acid conversion percentage was 94.83% for model acid oil after 60 mm and further time is not required, while for WCOI was 52.14 % after 90 mm and for WCO2 was 83.37 % also after 60 mm this was by using 6:1 methanol to oil, 2.5% H2S04, 300 rpm and 60±1 °C.
The second step of the reaction was transestrification process using different parameters, alcohol to oil molar ratio, catalyst amount, reaction temperature, reaction time and catalyst type. Thermo gravimetric analysis (TGA) is demonstrated as a potential method for monitoring biodiesel production by transestrification comparing the results with Gas chromatography (GC). The highest yield was 98.65 % using TGA analysis and 97.6% using GC at 10:1 methanol to oil, 300 rpm, 1% KOH , reaction temperature 55±1 °C and reaction time 60 mm.
The produced biodiesel with previous conditions using model acid oil was characterized using FTIR comparing the fingerprint with ASTM figure for fatty acid methyl ester, also comparing different factors studied according to peak intensity. Also thermal properties were studied by changing the heating rate and heating atmosphere. Finally biodiesel properties was studied for model acid oil , WCO1 and WCO2 according to ASTM comparing with diesel and biodiesel standard values and also comparing with different types of oil used in biodiesel preparation with different processes and it was found that the produced biodiesel has highest flash point and lower cloud and pour point than the other prepared ones. Other properties of biodiesel as water content, ash content and distillation temperature have values within the ranges of standard method for diesel and biodiesel.
Finally, kinetic study was done for esterification reaction, the reaction was assumed to be pseudo-homogeneous, first-order in the forward direction and second-order in the reverse direction. The values for the rate constant (K) was calculated at best fit for different 13 values with highest R2 comparing the calculated and theoretical values.
While for transestrification reaction, factors studied were fitted by using polynomial function with different degree according to the drawn points for each factor, then a model equation was used to join this factors, this model concluded that the most effective factor is the molar ratio.