Saqlain Shahid, Zhao Shufang, Kim Soong Yeon, Kim Young Dok
Department of Chemistry, Sungkyunkwan University, Suwon 16419, South Korea.
Department of Chemistry, Sungkyunkwan University, Suwon 16419, South Korea.
J Hazard Mater. 2021 Sep 15;418:126317. doi: 10.1016/j.jhazmat.2021.126317. Epub 2021 Jun 4.
Toluene removal rates using activated carbon (AC) at various relative humidity (RH) levels (0%, 30%, 60%) were compared under dark and visible-light conditions. Light exposure significantly increased toluene-removal efficiency independent of RH. When AC was pre-treated with an optimal concentration of HNO, its toluene-removal efficiency was enhanced further with light, an effect that can be attributed to increased surface-area and porosity. Fourier-transform infrared analysis confirmed that exposure of HNO-modified AC to light induced partial oxidation of toluene. Within visible-light range (380-650 nm), shorter wavelengths were more effective for toluene-removal compared with longer wavelengths. This suggests that hydroxyl groups formed on AC-surface under light strongly interact with aromatic rings of toluene, allowing for greater uptake of toluene. Moreover, AC can sustain its photo-activity when mixed with cement and cured, suggesting its potential applications in air-purifying building materials. An efficient and practical method for regeneration of spent AC is also demonstrated.
在黑暗和可见光条件下，比较了使用活性炭（AC）在不同相对湿度（RH）水平（0%、30%、60%）下的甲苯去除率。光照显著提高了甲苯去除效率，且与相对湿度无关。当用最佳浓度的HNO对AC进行预处理时，其甲苯去除效率在光照下进一步提高，这种效果可归因于表面积和孔隙率的增加。傅里叶变换红外分析证实，HNO改性的AC暴露于光下会导致甲苯的部分氧化。在可见光范围内（380 - 650纳米），与较长波长相比，较短波长对甲苯去除更有效。这表明光照下AC表面形成的羟基与甲苯的芳环强烈相互作用，从而使甲苯的吸附量更大。此外，AC与水泥混合固化后仍能保持其光活性，表明其在空气净化建筑材料中的潜在应用。还展示了一种高效且实用的废AC再生方法。
