Sulfuric acid and methanol were used for the pretreatment of
the fleshing oil and chicken fat. Certain amounts of the feedstock
were transferred to main reaction (120 l) tank for pretreatment
reactions. The feedstock was dried under vacuum to remove any
potential water. The required amount of alcohol was transferred
from the alcohol tank (200 l) to methoxide tank (120 l). The acid
catalyst was added to the tank manually. Methanol and catalyst
were mixed in the tank named as methoxide tank. The reactant
amounts differ from each other due to different FFA levels of the
feedstocks and those will be mentioned in the next sections. The
alcohol and catalyst mixture were stirred about 20 min in the
methoxide tank and then it was transferred to the reaction tank
when the temperature of the feedstock in the reaction tank