Wang Guang-hui

Isolation of microbe for asymmetric reduction of prochiral aromatic ketone and its reaction characters

The favorable microbes for the asymmetric reduction of prochiral aromatic ketones was isolated from soil using acetophenone as the sole carbon source, when the asymmetric reduction of acetophenone (ACP) to chiral α-phenethyl alcohol (PEA) was chosen as the model reaction. Two microbe strains with excellent catalytic activity were obtained. They were Geotrichum candidum and Pichia pastoris identified by bacteria identification. The product of the asymmetric reduction of ACP catalyzed by Pichia pastoris was mainly R-PEA and that by Geotrichum candidum was mainly S-PEA. The yield and enantiomeric excesses (e.e.) could respectively reach 75% and 90% for Pichia pastoris, and 80% and 70% for Geotrichum candidum, much higher than those catalyzed by baker’s yeast.

Biogenic Hierarchical MIL-125/TiO2@SiO2 Derived from Rice Husk and Enhanced Photocatalytic Properties for Dye Degradation

The hierarchical porous heterostructured MIL‐125/TiO2@SiO2 composites are successfully obtained by biogenic‐templated method using rice husk both as biomorphic. The products are characterized by X‐ray diffraction, N2‐adsorption‐desorption analysis, scanning electron microscopy and Fourier transform infrared spectroscopy. The results reveal that MIL‐125/TiO2@SiO2 possesses a hierarchical porous structure in scale from micrometer to nanometer with high Brunauer–Emmett–Teller (BET) surface area (385.7–902.7 m2 g−1). The photocatalytic mechanism was discussed in detail. Meanwhile, the activity of MIL‐125/TiO2@SiO2 for the photocatalytic degradation of rhodamine B in aqueous medium is significantly higher than that of P25. The current work provides some concept and methods in the development of MOF‐based photocatalysts.