MgO/CaO nanorods (MgO/CaO NRs) were synthesized using a diatomite substrate under the microwave irradiation. The synthesized composite exhibits well-developed rod-like morphology with 112.8 m²/g BET surface area. The synthetic MgO/CaO NRs were evaluated as a potential catalyst in the transesterification of non-edible castor oil into biodiesel. The catalyst achieved stunning catalytic performance with biodiesel yield of 96.2 % within 70 min using 6 wt.,% of it as loading value after fixing the temperature at 70 °C and the ethanol-to-the used castor oil molar ratio at 15:1 by normal mixing. The sonication effect resulted in an enhancement in the yield to about 98.8 % after 60 min only and reduced the required ethanol, catalyst dosage and temperature. The characterization of the resulted castor oil-based biodiesel by the two mixing technique is of strong matching with the qualifications of EN 14214 as well as the ASTM D-6571 international standards of biodiesel.

MgO / CaO纳米棒（MgO / CaO NRs）是在硅藻土的微波辐射下合成的。合成的复合材料具有112.8 m ²的发达的棒状形态/ g BET表面积。合成的MgO / CaO NRs被评估为非食用蓖麻油酯交换为生物柴油的潜在催化剂。将温度固定在70°C且乙醇与废蓖麻油的摩尔比固定为15：1后，该催化剂以70％的生物柴油收率达到了惊人的催化性能，生物柴油收率为96.2％，其中6 wt。％作为负载量。通过正常混合。仅在60分钟后，超声处理的结果将收率提高到约98.8％，并降低了所需的乙醇，催化剂的用量和温度。通过两种混合技术对所得的蓖麻油基生物柴油的表征与EN 14214的资格以及ASTM D-6571国际生物柴油标准高度匹配。