Abstract
Improvement of reaction system for the fixed bed high quality biodiesel (HiBD) production has been investigated. When the HiBD production, catalytic cracking of waste cooking oil over a MgO/SiO2 catalyst, was conducted with a conventional down flow type fixed bed reactor, yield of oil (C4-C18hydrocarbons) obtained at 450 °C was 55% with a large amount of C19+ oxygenated compounds (about 30 %). On the other hand, the oil yield at 430 °C with an up flow type reactor was higher (above 60 %), and the oxygenates yield decreased. Addition of water to the reactant oil in the form of emulsion was found to promote the hydrolysis of triglycerides to free fatty acids and the oil yields also improved for both down flow and up flow reactors. In the latter case, although yield of oxygenates increased compared without water, acid value did not increase. These findings show that the up flow type reactor is suitable for the formation of HiBD using a fixed bed reaction system.
