Influence of preparation methods on physicochemical properties of zirconia for transesterification of Nannochloropsis oculata microalga's oil

Abstract

In this study, zirconia was successfully synthesized using precipitation, sol-gel and hydrothermal methods. The effect of different preparation methods on the physicochemical properties of zirconia were studied using FTIR, surface area and pore analyzer, XRD, FESEM, NH 3 -TPD and CO 2 -TPD. The performance of synthesized zirconia as heterogeneous catalyst to convert Nannochloropsis oculata (N. oculata) oil to biodiesel was also investigated. FTIR results confirmed that the selected calcination temperature is suitable for complete decomposition of organic components and the formation of zirconia phase. It was found that zirconia synthesized using precipitation method shows the highest surface area. However, zirconia synthesized by sol-gel method shows the highest composition of tetragonal crystallite structure. All the samples possess both the acid and basic sites with different strength. The highest lipid conversion (67.86 %) is obtained using zirconia synthesized using sol-gel method.