Pillaring of bentonite clay with Zr, Ti, and Ti/Zr by ultrasonic technique for biodiesel production

The current study concentrated on employing metal pillared bentonite catalysts to transform waste cooking oil. The goal of this research was to create pillared bentonite catalyst for effective low temperature conversion. The ultrasonic technique was used to prepare pillared bentonite with varied polycations (Zr, Ti, and mixed Ti/Zr) and varied sonication time (10, 30, 50 min) as catalysts for biodiesel production. The characterization of pillared bentonite (Zr-pillared interlayered clay (PILC), Ti-pillared interlayered clay (PILC), Ti/Zr-pillared interlayered clay (PILC)) and calcium bentonite (Ca-B) was conducted by NH₃-TPD, XRF, BET, X-ray diffractometer (XRD), FTIR, and RAMAN analysis. The pillared bentonite as catalyst had powder and pore structure with high surface area, acidity, and excellent performance. The pillared bentonite catalysts increased in specific surface area of two to seven times, and the basal spacing expanded. In comparison to Ca-B, their morphology surfaces significantly changed, resulting in smaller pore size and greater total acidity values. Ti-PiLC and Ti/ZrPiLC catalysts were sonicated for 10 min, whereas Zr-PILC was sonicated for 30 min and produced the highest surface area results when compared to the other variations. The acidity of the Ti/Zr-PILC catalyst is 949–1117 µmol/g, and its surface area is 158–169 m²/g. According to the catalytic test, the total conversion formed for 6-hour reaction at 100 °C, and 60 bar of initial CO₂ pressure was 78.43%.