1 Utilization of Pomacea Sp Shell as Catalyst for Biodiesel Production: Full Factorial Design Optimization Ong Lu Ki, Suryadi Ismadji*, Aning Ayucitra, Felycia Edi Soetaredjo, Yosephine Yulia Margaretha, Henry Sanaga Prasetya Department of Chemical Engineering, Widya Mandala Surabaya Catholic University, Kalijudan 37, Surabaya 60114, Indonesia Abstract Utilization of golden snail (Pomacea Sp) shell as catalyst for biodiesel production was studied using full factorial design optimization to determine the optimum condition of biodiesel production. CaO catalyst was produced by calcination of golden snail (Pomacea Sp) shell at 900 o C for 2 h in a tubular furnace. The catalyst and golden snail shell were characterized using nitrogen sorption analysis, FTIR analysis, X-Ray Fluorescense (XRF) spectrometry and X-Ray Diffraction method. The optimum condition of the model is obtained by employing 5% catalyst and methanol/oil ratio of 5:1 and those from real data are 4% catalyst and methanol/oil ratio of 7:1 with a difference of FAME yield percentage of 2.07%. Keywords: golden snail shell; biodiesel; CaO catalyst *corresponding author: suryadiismadji@yahoo.com, Tel. +62 313891264, Fax. +62 313891267