The sustainable production of biodiesel from waste materials has become of utmost importance in recent years. In this study, cheap CaO catalysts were prepared by calcination of waste scallop seashells (Noble Pectin). The seashells were thermally treated at different temperatures (600–1000 °C) and then used in the transesterification of sunflower oil for biodiesel production. The catalysts were characterized using Fourier Transform Infrared Spectroscopy (FTIR) and simultaneous Thermal Gravimetric-Differential Scanning Calorimetry (TG-DSC) techniques. The highest Fatty Acid Methyl Esters (FAME) yield (97%) was obtained in the presence of the catalyst calcined at 700 °C under the following conditions: a methanol-to-oil molar ratio (MOMR) of 12:1, a catalyst-to-oil ratio (CTOR) of 10 wt%, a stirring rate of 700 rpm, a reaction temperature of 65 °C and a reaction time of 4 h. The seashell-derived catalyst was practically stable for at least 4 consecutive runs in the reusability study, maintaining a high FAME yield (>92%). The reaction followed pseudo-first order kinetics, with an activation energy (Ea) of 133.57 kJ/mol and a pre-exponential factor (A) of 4.025 × 10¹⁸ min⁻¹. This catalyst additionally exhibited a very high activity in the transesterification of waste cooking oil, with a similar FAME yield of 97%. This shows that this catalyst is promising for potential biodiesel production scale-up schemes and industrial applications.

近年来，利用废料可持续生产生物柴油已变得至关重要。在这项研究中，廉价的 CaO 催化剂是通过煅烧废弃的扇贝贝壳 (Noble Pectin) 制备的。贝壳在不同温度（600-1000°C）下进行热处理，然后用于向日葵油的酯交换反应以生产生物柴油。使用傅立叶变换红外光谱 (FTIR) 和同步热重-差示扫描量热法 (TG-DSC) 技术对催化剂进行了表征。最高脂肪酸甲酯 (FAME) 产率 (97%) 是在催化剂存在的情况下在 700 °C 下在以下条件下煅烧的：甲醇与油的摩尔比 (MOMR) 为 12:1，催化剂-油比 (CTOR) 为 10 wt%，搅拌速率为 700 rpm，反应温度 65 °C，反应时间 4 h。贝壳衍生的催化剂在可重复使用性研究中至少连续运行 4 次实际上是稳定的，保持了高 FAME 产率 (>92%)。该反应遵循伪一级动力学，活化能 (Ea) 为 133.57 kJ/mol，指前因子 (A) 为 4.025 × 10¹⁸分钟^-1。该催化剂在废弃食用油的酯交换反应中还表现出非常高的活性，FAME 产率为 97%。这表明该催化剂有望用于潜在的生物柴油生产放大计划和工业应用。