Luis A May Ix, Sandra Cipagauta Díaz, Francisco Tzompantzi, Raúl Pérez Hernández, Jorge M Meichtry, Emilia B Halac, Marta I Litter
{"title":"利用源自层状双氢氧化物的 ZnAlFe 混合金属氧化物去除亚砷酸盐。","authors":"Luis A May Ix, Sandra Cipagauta Díaz, Francisco Tzompantzi, Raúl Pérez Hernández, Jorge M Meichtry, Emilia B Halac, Marta I Litter","doi":"10.1016/j.chemosphere.2024.143694","DOIUrl":null,"url":null,"abstract":"<p><p>ZnAlFe mixed metal oxides (ZnAlFe-MMOs) were synthesized from layered double hydroxides (LDHs) prepared by the coprecipitation method at pH 9 using an initial weight composition of Zn<sup>2+</sup> = 75%, Al<sup>3+</sup> = 15% and Fe<sup>3+</sup> = 10%, with or without the addition of citric or oxalic acid. The solids were calcined at 400 °C to obtain the respective MMOs, which exhibited relatively high specific surface areas (165.3 - 63.8 m<sup>2</sup> g<sup>-1</sup>) and semiconductor properties active in the visible region (bandgap values (E<sub>g</sub>) of 2.42 - 1.77 eV). The synthesized materials were tested for the removal of trivalent arsenic by adsorption and by photocatalysis under visible light irradiation (λ ≥ 420 nm). The best removal of As(III) by adsorption (65.9%) and by photocatalysis (99.9%) was obtained with the ZnAlFe-MMOs prepared in the absence of organic acids. The XPS results indicate the coexistence of As<sup>3+</sup> and As<sup>5+</sup> over ZnAlFe-MMOs after the photocatalytic reaction and also confirm the formation of Fe<sup>2+</sup> sites on the hematite surface that enhances the removal of As(III). Raman measurements confirmed that, in the photocatalytic experiments, As is largely retained as As(V) on ZnAlFe-MMOs, bound to Fe. The results of fluorescence of 7-hydroxycoumarin suggest that the photocatalyst produces HO<sup>•</sup>, which can be the main species for As(III) oxidation under UV-Vis irradiation. Moreover, ZnAlFe-MMOs exhibited a good reusability after regeneration making ZnAlFe-MMOs a promising material for arsenic decontamination in polluted water.</p>","PeriodicalId":93933,"journal":{"name":"Chemosphere","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Arsenite removal by using ZnAlFe mixed metal oxides derived from layered double hydroxides.\",\"authors\":\"Luis A May Ix, Sandra Cipagauta Díaz, Francisco Tzompantzi, Raúl Pérez Hernández, Jorge M Meichtry, Emilia B Halac, Marta I Litter\",\"doi\":\"10.1016/j.chemosphere.2024.143694\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p><p>ZnAlFe mixed metal oxides (ZnAlFe-MMOs) were synthesized from layered double hydroxides (LDHs) prepared by the coprecipitation method at pH 9 using an initial weight composition of Zn<sup>2+</sup> = 75%, Al<sup>3+</sup> = 15% and Fe<sup>3+</sup> = 10%, with or without the addition of citric or oxalic acid. The solids were calcined at 400 °C to obtain the respective MMOs, which exhibited relatively high specific surface areas (165.3 - 63.8 m<sup>2</sup> g<sup>-1</sup>) and semiconductor properties active in the visible region (bandgap values (E<sub>g</sub>) of 2.42 - 1.77 eV). The synthesized materials were tested for the removal of trivalent arsenic by adsorption and by photocatalysis under visible light irradiation (λ ≥ 420 nm). The best removal of As(III) by adsorption (65.9%) and by photocatalysis (99.9%) was obtained with the ZnAlFe-MMOs prepared in the absence of organic acids. The XPS results indicate the coexistence of As<sup>3+</sup> and As<sup>5+</sup> over ZnAlFe-MMOs after the photocatalytic reaction and also confirm the formation of Fe<sup>2+</sup> sites on the hematite surface that enhances the removal of As(III). Raman measurements confirmed that, in the photocatalytic experiments, As is largely retained as As(V) on ZnAlFe-MMOs, bound to Fe. The results of fluorescence of 7-hydroxycoumarin suggest that the photocatalyst produces HO<sup>•</sup>, which can be the main species for As(III) oxidation under UV-Vis irradiation. Moreover, ZnAlFe-MMOs exhibited a good reusability after regeneration making ZnAlFe-MMOs a promising material for arsenic decontamination in polluted water.</p>\",\"PeriodicalId\":93933,\"journal\":{\"name\":\"Chemosphere\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2024-11-12\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Chemosphere\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.1016/j.chemosphere.2024.143694\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Chemosphere","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1016/j.chemosphere.2024.143694","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
Arsenite removal by using ZnAlFe mixed metal oxides derived from layered double hydroxides.
ZnAlFe mixed metal oxides (ZnAlFe-MMOs) were synthesized from layered double hydroxides (LDHs) prepared by the coprecipitation method at pH 9 using an initial weight composition of Zn2+ = 75%, Al3+ = 15% and Fe3+ = 10%, with or without the addition of citric or oxalic acid. The solids were calcined at 400 °C to obtain the respective MMOs, which exhibited relatively high specific surface areas (165.3 - 63.8 m2 g-1) and semiconductor properties active in the visible region (bandgap values (Eg) of 2.42 - 1.77 eV). The synthesized materials were tested for the removal of trivalent arsenic by adsorption and by photocatalysis under visible light irradiation (λ ≥ 420 nm). The best removal of As(III) by adsorption (65.9%) and by photocatalysis (99.9%) was obtained with the ZnAlFe-MMOs prepared in the absence of organic acids. The XPS results indicate the coexistence of As3+ and As5+ over ZnAlFe-MMOs after the photocatalytic reaction and also confirm the formation of Fe2+ sites on the hematite surface that enhances the removal of As(III). Raman measurements confirmed that, in the photocatalytic experiments, As is largely retained as As(V) on ZnAlFe-MMOs, bound to Fe. The results of fluorescence of 7-hydroxycoumarin suggest that the photocatalyst produces HO•, which can be the main species for As(III) oxidation under UV-Vis irradiation. Moreover, ZnAlFe-MMOs exhibited a good reusability after regeneration making ZnAlFe-MMOs a promising material for arsenic decontamination in polluted water.