Abstract Ultra-violet photocatalytic oxidation (UV PCO) technology has been receiving extensive attention for indoor air purification in recent two decades. However, the formation of by-products during the UV-PCO process darken its prospect of providing healthy indoor air quality (IAQ). This study examines by-product generation and operational parameters from 36 UV-PCO tests using a pilot duct system with the objectives of developing reliable by-product predictive models. The statistical analysis aimed at establishing linear and non-linear regression models to predict the concentrations of formaldehyde and acetaldehyde based on factors such as concentration, RH, airflow, and irradiance. The developed linear models provided satisfactory estimations of acetaldehyde and the sum of formaldehyde and acetaldehyde (FA) levels with regression coefficients (R2) of 0.74 and 0.84, respectively. Parametric study and bivariate analysis further confirm the statistical significance of independent variables on the acetaldehyde and FA productions. The PCO reaction pathway was proposed to explain that the presence of some strongly bounded intermediates on the surface decreased the reactivity of acetaldehyde to be further oxidized to formaldehyde.

中文翻译：

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光催化氧化 (PCO) 室内空气净化器副产品的建模：乙醇案例研究

摘要 近二十年来，紫外光催化氧化（UV PCO）技术在室内空气净化领域受到广泛关注。然而，UV-PCO 过程中副产品的形成使其提供健康室内空气质量 (IAQ) 的前景黯然失色。本研究使用先导管道系统检查 36 次 UV-PCO 测试的副产品生成和操作参数，目的是开发可靠的副产品预测模型。统计分析旨在建立线性和非线性回归模型，根据浓度、相对湿度、气流和辐照度等因素预测甲醛和乙醛的浓度。开发的线性模型提供了令人满意的乙醛估计值以及甲醛和乙醛 (FA) 水平的总和，回归系数 (R2) 分别为 0.74 和 0.84。参数研究和双变量分析进一步证实了自变量对乙醛和 FA 产量的统计显着性。提出PCO反应途径来解释表面上一些强结合中间体的存在降低了乙醛进一步氧化成甲醛的反应性。