Design consideration of photocatalytic oxidation reactors using TiO2-coated foam nickels for degrading indoor gaseous formaldehyde

Technologies for the removal of phenol from fluid streams: A short review of recent developments

“…In a recent paper [187], based on theoretical analyses, a novel photocatalytic oxidation (PCO) reactor for air deodorization (Fig. 8), containing 15 parallel-connected cells was designed.…”

Research on photodegradation of formaldehyde by nanocrystalline N-TiO2 powders under visible light irradiation

“…Many methods have been attempted to decompose and remove these gaseous pollutants. In recent years, the decomposition of formaldehyde by photocatalysts has attracted increasing attention [1][2][3][4]. Many researchers have focused their research on removing indoor air pollutants by using titanium dioxide (TiO 2 ) as a photocatalyst, because a wide range of organic compounds can be decomposed to CO 2 and H 2 O at room temperature on TiO 2 catalysts in the presence of UV illumination [5][6][7][8][9][10].…”

Removal of Low-Concentration Formaldehyde by a Fiber Optic Illuminated Honeycomb Monolith Photocatalytic Reactor

“…and Fujishima, 1998;Ao et al, 2004;Yu et al, 2006a;Zuo et al, 2006;Hodgson et al, 2007;Wang et al, 2007;Yang et al, 2007a;Shie et al, 2008;Zhang and Liu, 2008;Chen et al, 2009;Mo et al, 2009;Lu et al, 2010;Aïssa et al, 2011;Bourgeois et al, 2012;Han et al, 2012;Dozzi et al, 2013). In the photocatalytic oxidation, the ultraviolet (UV) radiation with energy above the band-gap of titanium dioxide (TiO 2 ) (wavelength < 385 nm) can induce the formation of electron-hole pairs and generate hydroxyl radicals further on the UV-illuminated TiO 2 surface, and then the oxidation of organic contaminants to H 2 O, CO 2 and other final products is mediated by hydroxyl radicals (Anpo et al, 1991;Yu et al, 2006b;Zuo et al, 2006;Hodgson et al, 2007;Yu and Lee, 2007;Mo et al, 2009Sun et al, 2010Yu et al, 2010;Kandiel et al, 2013;Klementova and Zlamal, 2013;Silva et al, 2013).…”

“…In the photocatalytic oxidation, the ultraviolet (UV) radiation with energy above the band-gap of titanium dioxide (TiO 2 ) (wavelength < 385 nm) can induce the formation of electron-hole pairs and generate hydroxyl radicals further on the UV-illuminated TiO 2 surface, and then the oxidation of organic contaminants to H 2 O, CO 2 and other final products is mediated by hydroxyl radicals (Anpo et al, 1991;Yu et al, 2006b;Zuo et al, 2006;Hodgson et al, 2007;Yu and Lee, 2007;Mo et al, 2009Sun et al, 2010Yu et al, 2010;Kandiel et al, 2013;Klementova and Zlamal, 2013;Silva et al, 2013). The key photocatalytic oxidation and reduction processes in the degradation of formaldehyde can be expressed as what follows (Noguchi and Fujishima, 1998;Ao et al, 2004) A variety of photocatalytic reactors have been designed for indoor air purification, such as plate (Yu et al, 2006b;Zuo et al, 2006;Yang et al, 2007b;Yu and Lee, 2007;Chen et al, 2009;Yu et al, 2010), honeycomb monolith (Hodgson et al, 2007;Wu et al, 2013;Yu et al, 2014), annular (Yang et al, 2007a;Shie et al, 2008), packed-bed (Han et al, 2012), and optical fiber (Bourgeois et al, 2012). Among these reactors, the performances of plate [once-flow removal efficiency (ORE): 11-19.6% (Yang et al, 2007b); 50% (Chen et al, 2009)] and annular [ORE: 8-14% (Yang et al, 2007a)] reactors on formaldehyde decomposition were lower than those of the packed-bed [ORE: 40-90% (Han et al, 2012)], optical fiber [ORE: 60% (Bourgeois et al, 2012)] and the honeycomb monolith type [ORE: 35-86% (Hodgson et al, 2007;…”

“…The key photocatalytic oxidation and reduction processes in the degradation of formaldehyde can be expressed as what follows (Noguchi and Fujishima, 1998;Ao et al, 2004) A variety of photocatalytic reactors have been designed for indoor air purification, such as plate (Yu et al, 2006b;Zuo et al, 2006;Yang et al, 2007b;Yu and Lee, 2007;Chen et al, 2009;Yu et al, 2010), honeycomb monolith (Hodgson et al, 2007;Wu et al, 2013;Yu et al, 2014), annular (Yang et al, 2007a;Shie et al, 2008), packed-bed (Han et al, 2012), and optical fiber (Bourgeois et al, 2012). Among these reactors, the performances of plate [once-flow removal efficiency (ORE): 11-19.6% (Yang et al, 2007b); 50% (Chen et al, 2009)] and annular [ORE: 8-14% (Yang et al, 2007a)] reactors on formaldehyde decomposition were lower than those of the packed-bed [ORE: 40-90% (Han et al, 2012)], optical fiber [ORE: 60% (Bourgeois et al, 2012)] and the honeycomb monolith type [ORE: 35-86% (Hodgson et al, 2007;Mo et al, 2009)]. In our previous study, we had successfully improved the removal efficiency of α-pinene to > 90% by using a fiber optic illuminated honeycomb monolith photocatalytic reactor (Yu et al, 2014).…”