Abstract
The transesterification experiments of triolein with ethanol using various ion-exchange resins were conducted to produce the ethyl oleate which is available as a biodiesel fuel. The anion-exchange resins, Diaion PA308, PA306s and HPA25, showed much more catalytic activities than the cation-exchange resin, Diaion PK208. Among the anion-exchange resins, PA306s with the lowest crosslinking degree was most active. For PA306s of 4 g, the conversion of triolein to ethyl oleate reached about 90 % at 1.5 hours, which was reasonably comparable to the results using the conventional homogeneous catalysts, NaOH and KOH. The continuous transesterification experiments were carried out using an expanded-bed reactor packed with PA306s. The bed expansion was linearly related with the flow rate and the bed voidage and the residence time through the expanded-bed was calculated by this relation. The concentration of ethyl oleate in the effluent solution increased with the residence time and then hardly changed over 20 min. The transesterification was considered to be in the equilibrium state at this residence time. The equilibrium conversion of triolein to ethyl oleate was about 60 %.
