Adsorption and photocatalytic degradation of phenol and 2,4 dichlorophenoxiacetic acid by Mg–Zn–Al layered double hydroxides

Geomaterials: their application to environmental remediation

“…To realize photocatalysts, polyoxometalate and semiconductor particles, such as TiO 2 , ZnS and CdS, were immobilized in the interlayer space of LDHs. However, few studies [113,114] have addressed the photocatalytic behaviors of LDHs in regard to organic substances. Patzko et al [115] evaluated the photocatalytic properties of a calcined Zn-Al LDH intercalated with ZnO.…”

“…Patzko et al [115] evaluated the photocatalytic properties of a calcined Zn-Al LDH intercalated with ZnO. Phenol [114] and/or 2,4 dichlorophenoxyacetic acid [116] were photocatalytically degraded using calcined Mg-Zn-Al and Zn-Al-Fe LDHs, respectively. The photodegradation of a methyl orange dye by an untreated Zn-Al LDH was investigated, but the sample was contaminated by a ZnO phase during the synthesis [113], and thus the photocatalytic properties of uncalcined LDHs remain unclear.…”

Tuning the acidic–basic properties by Zn-substitution in Mg–Al hydrotalcites as optimal catalysts for the aldol condensation reaction

“…On the other hand, the modification of the c parameter is directly related with the diminishing of the interlayer distances (Table 1). Valente et al [27] explained this phenomenon as a consequence of an increase in layer charge density due to the larger electronegativity of Zn compared to that of Mg (1.66 and 1.29, respectively). This situation also affects the crystal domain size calculated on the as-synthesized LDHs in direction c, due to the stacking of the layer flakes.…”

Hybrid Inorganic/Organic Composites of Layered Double Hydroxides Intercalated with Organic Acid Anions for the Uptake of Hazardous Substances from Aqueous Solution

“…The materials are known to function as effective anion adsorbents in the uptake of phenols, terephthalate, anionic surfactants, ionizable pesticides and herbicides, humic and fulvic acid, anionic dyes, and colored organics from aqueous solutions (Ulibarri et al, 1995;Hermosin et al, 1996;Pavlovic et al, 1997;Barriga et al, 2002;Crepaldi et al, 2002;You et al, 2002a;Orthman et al, 2003;Pavlovic et al, 2005;Li et al, 2005;Cardoso and Valim, 2006;Vreysen and Maes, 2008;Chao et al, 2009;Gaini et al, 2009;Valente et al, 2009;Setti et al, 2010;Sun et al, 2010). Based on the ability of LDH to intercalate various types of anions in interlayers, organic-inorganic composite materials could be produced by intercalation of organic anions having functional groups in their structure into the interlayers of LDH.…”