Various key scientific issues in the resource utilization processes including the synergistic enhancement of multiphase transport and reaction, the control mechanism of nano/micro-structure interface in separation processes, process intensification and integration in pollution control, etc. have been investigated. Key technologies as well as novel equipment and processes on green separation and reaction engineering have been developed to tackle the industrial challenge of high energy and material consumption and pollution caused by low efficiency in separation and low reaction selectivity. These will serve as the theoretical and technical basis to support the research and development of chemical, metallurgical and environmental industries.
Artificial electrochemical nitrogen fixation technology
Aiming at the problem of high bond energy of inert N2 molecules and difficulty in activation of N≡N bonds, the novel strategy for regulating the atomic architecture and local electronic state of the catalyst is proposed. We designed the NiTe nanocrystal (Adv Funct Mater., 2020,30,2004208), Ni2P/N,P-C hybrids (J Mater Chem A., 2020,8,2691) and metal @NCNTs heterostructure for high activity and selective electrocatalytic nitrogen fixation to ammonia under ambient conditions. They are beneficial for clarifying the adsorption and activation mechanism of N2 molecules on the catalyst surface.
Fig. 1 Electrocatalytic nitrogen fixation performance of NiTe nanocrystals with different surface atomic architectures (left) and the related work was selected as the cover picture of Advanced Functional Materials (right).
Key technology of enzymatic synthesis and green separation of bulk antibiotics & its industrial application
Key technology of bulk API cefalexin enzymatic synthesis and green separation had successfully broken-through, and the whole clean process integration was achieved further. The demonstration project of enzymatic synthesis cefalexin with 1000 tons per year was established. The steady operation of this process showed that COD in wastewater was reduced by more than 40%, organic solvents and sub-raw materials declined by 70% and 100% respectively, and the production cost per unit of cefalexin was reduced by 4.7%.
Fig. 2 Antibiotics enzymatic synthesis equipment
Equilateral docosahedral strontium titanate single crystal material
Strontium titanate (SrTiO3) is a typical perovskite semiconductor material with anisotropic transport of electrons and holes on the interface, and known for its ultra-high quantum efficiency and photocatalytic activity. Regular shaped 22-facet single-crystalline SrTiO3 particles were successfully produced. The photocatalytic activity was 3.42 times larger than ordinary cubic single crystals and 4.23 times larger than commercial SrTiO3 nanoparticles. The band structure as well as the anisotropic nature of the density of states have been studied on the basis of the density functional theory (DFT). The use of high-performance 22-facet SrTiO3 crystals would be promising in various applications including degradation of organic compounds, hydrogen production by photoelectrolysis, and photocatalytic conversion of CO2.
Fig. 3 HRTEM images, SAED pattern and the shape diagram of 22-facet single-crystalline SrTiO3 particles
Fig. 4 Band structures of 22-facet single-crystalline SrTiO3