In this work, the synthesis of sodium titanate for the biodiesel production was evaluated with emphasis on the synthesis parameters of titanates in the conversion of vegetable oil to biodiesel. Sodium titanate catalysts were synthesized via sol–gel hydrothermal method and tested as heterogeneous catalysts for biodiesel production, using a factorial design 2^k. Four experimental factors were considered: NaOH concentration, hydrothermal temperature, TiO₂/NaOH ratio, and calcination temperature, using as response variable the catalysts activity in soybean oil conversion to biodiesel. Titanates were characterized by XRD, SEM, and N₂ physisorption techniques. The presence of tri and hexatitanate were confirmed. Trititanate was the most efficient in the conversion of soybean oil to biodiesel, achieving around 80% with an alcohol:oil molar ratio of 6:1 at 55°C for 5 hr and 300 rpm. Among the trititanate catalysts, the best performing sample showed a surface area of 217 m²/g with a porous size average of 4.8 nm related to nanotube structure with inter and intra particle mesoporosity. Conditions to prepare the efficient performing catalyst were as follows: NaOH concentration, 7.5 M; hydrothermal temperature, 130°C; TiO₂/NaOH ratio, 0.06 g/mL; and calcination temperature, 600°C.

中文翻译：

---

使用析因设计合成钛酸钠催化剂用于生物柴油生产

在这项工作中，评估了用于生物柴油生产的钛酸钠的合成，重点是在植物油转化为生物柴油的过程中钛酸酯的合成参数。钛酸钠催化剂是通过溶胶-凝胶水热法合成的，并通过2 ^k析因设计作为生物柴油生产的非均相催化剂进行了测试。考虑了四个实验因素：NaOH浓度，水热温度，TiO ₂ / NaOH比率和煅烧温度，使用响应值作为催化剂的作用，将大豆油转化为生物柴油的催化剂活性。钛酸盐通过XRD，SEM和N ₂表征物理吸附技术。确认存在三和六钛酸酯。Trititanate在将大豆油转化为生物柴油方面最有效，在55°C下以5：300和300 rpm的乙醇：油摩尔比为6：1达到了80％左右。在三钛酸酯催化剂中，性能最好的样品显示的表面积为217 m ² / g，其平均孔径为4.8 nm，这与具有颗粒间和颗粒间介孔的纳米管结构有关。制备高效催化剂的条件如下：NaOH浓度为7.5M； NaOH为7.5M。水热温度130°C; TiO ₂ / NaOH比率为0.06g / mL；煅烧温度为600℃。