双配体仿酶催化剂的制备及其光催化降解水中对苯二酚

Preparation of Dual Ligand Imitation Enzyme Catalysts and Its Use in Photodegradation of Hydroquinone in Water

以天然氯化血红素和咪唑为原料,制备了咪唑轴向五配位型的双配体配合物,并将其负载于羟基功能化的纤维素磁微球表面。通过紫外-可见分光光度、傅里叶变换红外光谱、透射电子显微镜、热重分析和振动样品磁强(VSM)对催化剂进行表征。在模拟太阳光照射下,以水中溶解氧为氧化剂,考察了该催化剂降解模拟废水中有机污染物对苯二酚(HQ)的性能。结果表明,在300 W氙灯照射下,当催化剂用量0.2 g/L、HQ初始浓度20 mg/L及pH值为6的条件下,6 h后HQ的降解率达到96.97%,催化剂重复使用5次后,降解率仍可达92%以上。同时对该催化剂光催化降解对苯二酚的机理进行了初步研究。

An axial imidazole five-coordinate biomimetic catalyst was prepared from natural hemin and imidazole, and was immobilized on the surface of magnetic cellulose nanospheres. These modified nanospheres were characterized by UV-visible （UV-Vis） spectrophotometer, Fourier transform infrared spectroscopy （FT-IR）, transmission electron microscopy（ TEM）, thermal gravimetric analysis （TGA） and vibrating sample magnetometry（VSM）. Their photocatalytic activity and stability were evaluated by the catalytic degradation of hydroquinone under visible light irradiation. The results show that 96. 97% of HQ was degraded with an initial concentration of HQ at 20 mg/L under simulated sunlight irradiation for 6 h at pH = 6 in the presence the catalyst at 0.2 g/L. After five-recycle, the photocatalyst still provides up to 92% degradation of HQ. The photocatalytic degradation mechanism of HQ under visible light irradiation was also investigated.