Preparation and Characterization of ZrO₂ Polycrystalline Ceramic Foam Catalyst for Production of Biodiesel

Characteristics of ZrO₂ polycrystalline ceramic foam catalyst including crystal structure, phase composition, and microstructure were analyzed by Py-IR, XRD, SEM, and BET. Effects of preparation conditions such as calcination temperature, calcination time, ZrO₂ (catalyst matrix), Al₂O₃ (flux), TiO₂ (stabilizer), NaHCO₃ (low-temperature pore-forming agents), and NaCl (high-temperature pore-forming agents) on catalytic activity were investigated. The optimum composition of ZrO₂ polycrystalline ceramic foam catalyst were optimized using response surface methodology (RSM) to be 88.47% ZrO₂, 9.62% Al₂O₃, 3.31% TiO₂, 10% NaHCO₃, and 25% NaCl (compared with the standard number 100). After calcination at 1550°C for 120 min, fatty acid methyl ester conversion rates were substantially maintained at around 97.31%, The FAME content in the product oil exceeded 97% after five successive reuses of the catalyst. In addition, catalytic activity did not significantly fluctuate. The proposed catalyst presents a new type of solid catalyst with excellent catalytic activity and stability.