Catalytic effect of γ-Al(OH)3, α-FeOOH, and α-Fe2O3 on the ozonation-based decomposition of diethyl phthalate adsorbed on sand and soil

Abstract

Diethyl phthalate (DEP) is a pollutant which can be found on soils as a result of its widespread application in plastic industry. Soil contaminated with DEP requires the application of different chemical methods to attain its remediation. Among these methods, ozonation has proven to be effective against toxic soil pollutants. The presence of metal oxides in soil is a possible source of catalytic effect. In this study, it was analyzed the catalytic effect of goethite (α-FeOOH), hematite (α-Fe 2 O 3 ), and gibbsite (γ-Al(OH) 3 ) in combination with O 3 to achieve DEP decomposition. The DEP elimination efficiency by ozonation on the sand increased according to the following order: without catalyst < γ-Al(OH) 3 < α-Fe 2 O 3 < α-FeOOH. Among these three oxides, goethite has the highest OH groups density. The reaction of OH groups and O 3 favors the formation of oxidant species, such as O 2 • − and OH•. The effect of the moisture content, the catalyst concentration, and the type of soil (sand and calcined soil) were also studied. The latter had a significant influence on the total organic carbon (TOC) removal. The mineralization degree was 84% in the O 3 -soil system, while only 40% was obtained with O 3 -sand (α-FeOOH) in dry sand after 8 h of treatment. Calcined soil promoted the increase of TOC removal due to the presence of different metal oxides, which were active centers for O 3 decomposition. The toxicity tests of the three reaction systems (O 3 -sand, O 3 -sand (α-FeOOH), and O 3 -soil) were evaluated on lettuce seed germination before and after DEP ozonation.

Cu–MnOX/γ-Al2O3 Catalyzed Ozonation of Nitrobenzene in a High-Gravity Rotating Packed Bed

“…Heterogeneous catalytic ozonation is a promising technology for the degradation and mineralization of refractory pollutants in an aqueous solution . The catalysts used for this purpose mainly include (1) metal oxides (e.g., MnO 2 , , Al 2 O 3 , , CeO 2 , , and FeOOH , ); (2) silicate materials (e.g., zeolite, , MCM-41, SBA-15, and cordierite); (3) metal and metal oxides-supported catalysts (e.g., Cu/Al 2 O 3 , MnO X /Al 2 O 3 , Co/AC, and FeOOH/Al 2 O 3 ); − and (4) activated carbon (AC). , Among these catalysts, γ-Al 2 O 3 -supported metal oxides show high activity for the catalytic oxidation of aromatic compounds and MnO 2 has an outstanding performance among the first transition metal. ,− The catalytic activity of MnO 2 is positively correlated with the number of surface hydroxyl groups and oxygen vacancies, and it can be improved by combining other metals such as Cu, Fe, and Ce oxides. , Li et al found that Cu/Mn-loaded γ-Al 2 O 3 showed enhanced catalytic activity for the removal of Acid Red B.…”

“…4 Heterogeneous catalytic ozonation is a promising technology for the degradation and mineralization of refractory pollutants in an aqueous solution. 5 The catalysts used for this purpose mainly include (1) metal oxides (e.g., MnO 2 , 6,7 Al 2 O 3 , 8,9 CeO 2 , 10,11 and FeOOH 12,13 ); (2) silicate materials (e.g., zeolite, 14,15 MCM-41, 16 SBA-15, 17 and cordierite 18 ); (3) metal and metal oxides-supported catalysts (e.g., Cu/Al 2 O 3 , MnO X /Al 2 O 3 , Co/AC, and FeOOH/Al 2 O 3 ); 19−22 and (4) activated carbon (AC). 23,24 Among these catalysts, γ-Al 2 O 3supported metal oxides show high activity for the catalytic oxidation of aromatic compounds and MnO 2 has an outstanding performance among the first transition metal.…”

Remediation of Diethyl Phthalate in Aqueous Effluents with TiO2-Supported Rh0 Nanoparticles as Multicatalytic Materials

“…In the same way, adsorptive removal proves to be effective for PAEs remediation, but presents high costs and requires further treatment. Finally, advanced oxidation processes (AOPs) have been considered as pertinent methodologies to remove phthalates from wastewaters [20,21], including the photochemically enhanced Fenton reaction [22,23], the combinations of TiO 2 or H 2 O 2 with ultraviolet (UV) light irradiation [20,24], ozonation reactions [25,26], and catalytic ozonation processes [27][28][29].…”