Productıon Of Glycerın-Free Bıofuel Wıth Transmethylatıon Reactıon Usıng Heterogenous Catalysts

Institution Of The Thesis: Gazi University, Turkey

Approval Date: 2017

Thesis Language: Turkish

Student: Alkin Özgen



In this study, the glycerol free biodiesel production by the transmethylation reaction, catalyst design and characterization of the resulting fuel were investigated. In the first phase of the study, a series of basic catalysts having different basicity were prepared by hydroxyapatite synthesis as catalyst support material and by impregnation of this support material with different potassium compounds. Maximum methyl ester yield of 94.5% has been achieved in the presence of HAP-A-KOH-%35 at the best reaction condition such as 7% by mass of catalyst relative to oil, DMC / canola oil ratio: 12/1, temperature: 85°C and reaction time: 9 hours. In the second phase of the study, commercially available basic and acidic catalysts were tested in the transmethylation reaction of oils with DMC. These catalysts gave methyl ester yields of about 48-70%. In the third phase of the study, the effects of different oil (such as canola, sunflower and soybean oil) on methyl ester yield were investigated. It has been found that the oil type has no effect on methyl ester yield. In addition, the oleic acid was added to the canola, sunflower and soya oil in proportions of 1, 3, 5, 7, 10 and 20% by mass and waste vegetable oil models with different free fatty acids were formed. As the amount of free fatty acid increases, the % methyl ester yield decreases to an average of 50% for each oil. This is due to the formation of a saponification side reaction between the free fatty acid and the KOH in the basic medium and the water is released in this reaction. In the last phase of the study, the fuel properties of the obtained fuel were investigated. The pour point and flash point of the produced fuel were found higher than of the other studies. Hence, the resulting fuel has been found to be more successful in terms of both cold air flow characteristics and safe handling and storage.