Hydrothermal growth of flower-like CaO for biodiesel production

摘要

Flower-like CaO has been fabricated by a simple hydrothermal approach. Detailed structural characterization revealed that, the flower-like products were constructed by conical-like crystals, with the angle between adjacent lateral edges being 30° or 25°. When flower-like CaO was used as the solid base catalyst to synthesize biodiesel, a high biodiesel yield of 95.5% was achieved. Preferred nucleation and growth of CaO nuclei along [2 2 2] and [4 0 0] growth directions led to conical-like CaO, which coalesced into fiower-like architectures by their further contacting and "welding" behavior. Flower-like CaO architectures predominantly exposed active O~(2-) on (2 2 2) and (4 0 0) favorable planes of CaO, resulting in obvious enhancement of catalytic activity and high yield of biodiesel.