Impact of intermediate products on benzene photocatalytic oxidation in pulp mills: Experimental and adsorption simulation study

The effects of water, substrate, and intermediate adsorption on the photocatalytic decomposition of air pollutants over nano-TiO2 photocatalysts

“…9b and c). 98 The photocatalytic reaction rate of C 6 H 6 in the subsequent stage significantly decreased, according to the experiment (Fig. 9a), which can be attributed to the negative effects of adsorption and photocatalysis.…”

“…9b-e). 98 The photocatalytic reaction rate of C 6 H 6 in the early stage was high and did not obviously change in the experiment (Fig. 9a), which can probably be explained by the opposing effects of adsorption and photocatalysis.…”

“…87 In terms of the complicated intermediates generated during the photocatalytic decomposition of air contaminants generated during papermaking, the photocatalytic and intermediate formation experiments, adsorption simulation of C 6 H 6 and various intermediates at different molar ratios, and the theoretical analysis of photocatalytic pathways were combined to explore the impact of C 6 H 6 intermediates on air-treatment efficiency. 98 The inactivation of the nano-TiO 2 colloid under a high C 6 H 6 concentration (841.97 ppm) was observed in the experiment (Fig. 9a) and was related to the competitive adsorption and surface reaction between C 6 H 6 and its intermediates.…”

“…9b, d, and e). 98 The multifactorial influence of water, substrate, and intermediate adsorption Since a variety of factors coexist in the air environment of papermaking industries, based on the influencing mechanism of a single factor from previous studies, 82,94,98 the multifactorial influence on papermaking air treatment was simultaneously considered by combining the experimental and theoretical results obtained from the adsorption calculation of 1-3 H 2 O (water), 1-3 HCHO (substrate), and 0-1 HCOOH molecules (intermediate) followed by the bandgap calculation of the TiO 2 photocatalyst (band structure and DOS). 99 The experiment results indicate that increasing the humidity (10-90%) originally increases and subsequently decreases both the photocatalytic reaction rate and degradation efficiency of HCHO.…”

“…Based on the discussions in Sections 3.1 to 3.4, the adsorption of water, substrates, and intermediates affecting photocatalytic degradation are usually in connection with the 98 number of active sites, the competitive adsorption of water and substrate, the amount of hydroxyl radicals, the amount of accessible substrate, and the competitive adsorption and photocatalytic reaction between the substrate components, intermediates, and parent molecules. Based on experimental and theoretical analyses the developments in the mechanisms underlying the effects of single and multiple factors related to water, substrate, and intermediate adsorption can provide theoretical guidance for the efficient and sustainable photocatalytic removal of air contaminants by regulating humidity (e.g., dehumidification) and substrate concentration (e.g., dilution) and reducing the aggregation of intermediate products on the catalyst (e.g., direct photolysis) in various industrial environments.…”