Abstract

Airborne microorganisms can cause various adverse effects, including infectious, allergic, and immunotoxic diseases. Bioaerosols are also one of the main causes of morbidity and mortality, as well as a heavy burden on health costs. The present study models and compares the inactivation performance of three commercial air filters, industrial and domestic use (vacuum cleaner) with and without catalyst (TiO₂) deposition for a model microorganism under UVA radiation. The filters were studied regarding catalysis load, adherence, optical properties, morphology, and cost. The microorganism used was E. coli, it was distributed emulating Flügge droplets on coated and uncoated filters and then exposed to UVA radiation at different humidity conditions. Different methods of bacterial spreading and counting on filters were tested. A simple kinetic model was proposed and validated to compare the inactivation performances of photocatalysis and photolysis; the modeling results enabled the prediction of inactivation efficiency and analysis of several parameters. To compare the photocatalytic activity of the functionalized filters we calculated D₉₀, the dose to reduce one bacterial log, and a pseudo-constant of the inactivation rate per unit mass of catalyst deposited. Our experimental findings of TiO₂-coated fiberglass filters presented in this study suggest that scaling up and its subsequent development in ventilation systems would be successful.

中文翻译：

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各种功能化过滤介质光催化灭活空气微生物的研究：比较分析

摘要

空气中的微生物可引起各种不良影响，包括传染性、过敏性和免疫毒性疾病。生物气溶胶也是发病和死亡的主要原因之一，也是健康成本的沉重负担。本研究模拟并比较了三种商用空气过滤器、工业和家用（真空吸尘器）在 UVA 辐射下有和没有催化剂 (TiO ₂ ) 沉积的模型微生物的灭活性能。研究了过滤器的催化负载、粘附性、光学特性、形态和成本。使用的微生物是大肠杆菌，将其模拟 Flügge 液滴分布在涂层和未涂层​​的过滤器上，然后在不同的湿度条件下暴露于 UVA 辐射。测试了不同的细菌传播和过滤器计数方法。提出并验证了一个简单的动力学模型来比较光催化和光解的失活性能；建模结果可以预测灭活效率并分析多个参数。为了比较功能化过滤器的光催化活性，我们计算了D ₉₀、减少一份细菌日志的剂量以及每单位质量沉积的催化剂的失活率的伪常数。_{我们在本研究中提出的 TiO 2}涂层玻璃纤维过滤器的实验结果表明，扩大规模及其在通风系统中的后续开发将会成功。