优化制备粒度均匀分布的Ce-Cu/TiO_2空心微球及其光-湿性能

Optimizing preparation of Ce-Cu/TiO_2 hollow microspheres with uniform particle size distribution and its photocatalysis and humidity control performance

以Ce(NO_3)_3×6H_2O和Cu(NO_3)_2×3H_2O为改性剂制备Ce-Cu/TiO_2空心微球,通过均匀设计与BP神经网络模型优化Ce-Cu/TiO_2空心微球的制备工艺参数。用激光粒度分析仪对Ce-Cu/TiO_2空心微球的粒度分布进行测试,用SEM和TEM对Ce-Cu/TiO_2空心微球的微观形貌进行表征,用比表面积及孔径测定仪对Ce-Cu/TiO_2空心微球的孔结构进行测试,采用等温吸放湿法对粒度均匀分布的Ce-Cu/TiO_2空心微球的湿性能进行测试,用紫外-可见分光光度计测试其光性能。结果表明,粒度均匀分布的Ce-Cu/TiO_2空心微球制备工艺参数为:磁力搅拌速度VMS=910 r/min、溶液B加入溶液A的速度VAB=1.32 mL/min、溶液D加入溶液C的速度VCD=0.86m L/min、煅烧升温速度VTC=2.47℃/min和煅烧温度TC=485℃,所制空心微球d10=103.74nm,d50=141.46 nm和d90=188.84 nm,粒径分布区间d90-d10为85.10 nm,空心微球具有良好的光-湿性能,1～6 h对甲醛气体的降解率为21.6%～53.9%,相对湿度32.28%～84.34%的平衡含湿量为0.0364～0.2746 g/g。

Cerous nitrate Ce(NO3)3?6 H2 O and cupric nitrate Cu(NO3)2?3 H2 O were used as modifier to make Ce-Cu/TiO2 hollow microspheres. The preparation scheme of Ce-Cu/TiO2 hollow microspheres with uniform particle size distribution was optimized by conducting uniform design and building BP neural network model. Particle size distribution of Ce-Cu/TiO2 hollow microspheres was tested and characterized by laser particle size analyzer(LPSA), the microstructure was characterized by SEM and TEM, the pore structure was tested by brunauer-emmett-teller surface areas analyzer(BET). Humidity performance of Ce-Cu/TiO2 hollow microspheres with uniform particle size distribution was tested by isothermal absorption-desorption,the photocatalysis performance was tested by ultraviolet-visible spectrophotometer(UV-Vis). Finally, optimal technology parameters of Ce-Cu/TiO2 hollow microspheres were obtained. The results showed that the magnetic stirring rate(VMS), dropping rate of solution B added to solution A(VAB), dropping rate of solution D added to solution C(VCD), calcination heating rate(VTC), and calcination temperature(TC) were 910 r/min, 1.32 mL/min, 0.86 mL/min, 2.47℃/min and 485℃, respectively. Besides, for Ce-Cu/TiO2 hollow microspheres with uniform particle size distribution, other sizes were shown as follows: d10 =103.74 nm, d50=141.46 nm and d90 =188.84 nm. Particle size distribution interval of d90-d10 was 85.10 nm. It was also proved that Ce-Cu/TiO2 hollow microspheres with uniform particle size distribution had good photocatalysis and humidity control performance. Specifically, degradation rate of formaldehyde gas was 21.6%~53.9% after 1~6 h, and equilibrium moisture content under the relative humidity of 32.28%~84.34% reached 0.0364~0.2746 g/g accordingly. The above research provided certain theoretical basis and technical support for further systematic research on particle size distribution of Ce-Cu/TiO2 hollow microspheres and photocatalysis-humidity control performance.