Instituto de Desarrollo Tecnológico para la Industria Química (INTEC, UNL-CONICET), Colectora RN 168 Km 472, 3000, Santa Fe, Argentina.
Environ Sci Pollut Res Int. 2021 May;28(19):23859-23867. doi: 10.1007/s11356-020-11663-6. Epub 2020 Nov 21.
Since COVID-19 pandemic, indoor air quality control has become a priority, and the development of air purification devices effective for disinfecting airborne viruses and bacteria is of outmost relevance. In this work, a photocatalytic device for the removal of airborne microorganisms is presented. It is an annular reactor filled with TiO-coated glass rings and irradiated internally and externally by UV-A lamps. B. subtilis spores and vegetative cells have been employed as model biological pollutants. Three types of assays with aerosolized bacterial suspensions were performed to evaluate distinct purification processes: filtration, photocatalytic inactivation in the air phase, and photocatalytic inactivation over the TiO-coated rings. The radiation distribution inside the reactor was analysed by performing Monte Carlo simulations of photon absorption in the photocatalytic bed. Complete removal of a high load of microorganisms in the air stream could be achieved in 1 h. Nevertheless, inactivation of retained bacteria in the reactor bed required longer irradiation periods: after 8 h under internal and external irradiation, the initial concentration of retained spores and vegetative cells was reduced by 68% and 99%, respectively. Efficiency parameters were also calculated to evaluate the influence of the irradiation conditions on the photocatalytic inactivation of bacteria attached at the coated rings.
自 COVID-19 大流行以来，室内空气质量控制已成为当务之急，开发有效消毒空气中病毒和细菌的空气净化设备至关重要。本工作提出了一种用于去除空气中微生物的光催化装置。它是一个填充有 TiO 涂层玻璃环的环形反应器，内部和外部均受到 UV-A 灯的照射。枯草芽孢杆菌孢子和营养细胞被用作模型生物污染物。进行了三种气溶胶细菌悬浮液的测试，以评估不同的净化过程：过滤、空气中的光催化失活和 TiO 涂层环上的光催化失活。通过对光催化床中光子吸收进行蒙特卡罗模拟分析了反应器内部的辐射分布。在 1 小时内可实现空气中高负荷微生物的完全去除。然而，要使反应器床中保留的细菌失活，则需要更长的照射时间：在内部和外部照射 8 小时后，保留的孢子和营养细胞的初始浓度分别减少了 68%和 99%。还计算了效率参数，以评估照射条件对附着在涂层环上的细菌的光催化失活的影响。
