壳聚糖基复合光催化剂及光催化纸的制备与性能研究

本研究将壳聚糖与光催化剂(实验室自制硅藻土基-N-掺杂TiO_2)复合制备壳聚糖基复合光催化剂,然后将其以一定比例与纸浆混合抄造光催化纸;采用扫描电子显微镜(SEM)、X射线衍射仪(XRD)和傅里叶变换红外光谱仪(FT-IR)等对复合光催化剂的形貌、结构及组成成分等进行了表征;利用SEM对光催化纸形态结构、催化剂分布状态等情况进行了分析,并分别对亚甲基蓝(MB)和甲醛进行了光催化降解实验。结果表明,复合光催化剂对MB和甲醛都有较好的光催化降解效果。在250 W高压汞灯照射7 h、检测波长分别为664 nm和630 nm条件下,复合光催化剂对MB的降解率达80%以上、对甲醛的降解率达49%以上;壳聚糖用量10%的复合光催化剂在纸张中的添加量20%时,光催化纸对甲醛的降解率为44%,其抗张指数从空白样的32. 4 N·m/g提升到34. 7 N·m/g,耐破指数从空白样的1. 68 kPa·m~2/g提升到2. 36 kPa·m~2/g。

Preparation and Properties of Chitosan-based Composite Photocatalyst and Photocatalytic Paper

In this study, chitosan and photocatalyst (self-made diatomite-N-doped TiO₂ in laboratory) were used to prepare chitosan-based composite photocatalyst.Then it was mixed with pulp in a certain ratio to prepare photocatalytic paper. The surface morphology, structure and composition of the composite photocatalyst were analyzed by scanning electron microscopy(SEM), X-ray diffraction(XRD) and Fourier transform infrared spectroscopy(FT-IR). The surface morphology, structure and composite photocatalyst distribution of the photocatalyst paper were analyzed by SEM. The photocatalytic degradation experiments of methylene blue (MB) and formaldehyde(HCHO) were carried out, which showed that the composite photocatalyst had a good photocatalytic degradation effect on MB and HCHO. Under the condition of 250 W high pressure mercury lamp irradiation for 7 hours and detection wavelength of 664 nm and 630 nm respectively, the degradation rate of MB and HCHO by composite photocatalyst was more than 80% and 49% respectively.The photocatalytic paper adding 20% composite photocatalyst with chitosan dosage of 10% had 44% degradation rate of HCHO.The tensile index of the photocatalytic paper increased from 32.4 N·m/g to 34.7 N·m/g, and the burst index increased from 1.68 kPa·m²/g to 2.36 kPa·m²/g.