Coexistence of adsorption and coagulation processes of both arsenate and NOM from contaminated groundwater by nanocrystallined Mg/Al layered double hydroxides.

摘要: In this study, nanocrystallined Mg/Al layered double hydroxides (LDH-CO3) and chloridion intercalated LDHs (LDH-Cl) were synthesized used for simultaneous removal of arsenic natural organic matter (NOM) from contaminated groundwater. Humic acid (HA) was selected as a model compound NOM. The maximum adsorption capacities arsenate (As(V)) on LDH-CO3 LDH-Cl are 44.66 88.30 mg/g, respectively, those HA 53.16 269.24 mg/g, respectively. It found that more than 98% 94% NOM eliminated by both NOM-rich groundwater, which is drinking water in Togtoh County, Inner Mongolia, China. concentration declined 231 to 4 μg/L, meets the standard. mechanisms determined using X-ray diffraction (XRD), Fourier transformed infrared (FTIR) spectroscopy, photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission (TEM) extended absorption fine structure techniques (EXAFS). results showed mainly via surface complexation well coagulation at LDHs, while As(V) ion-exchange process. presence exhibited little inhibiting effect occupying partial binding sites LDH surfaces. Nevertheless, it could not affect process with interlayer anions LDHs. can be carried out independently due different mechanisms. By integrating experimental results, clear potentially cost-effective material purification