Research on removal of fluoride in aqueous solution by alumina-modified expanded graphite composite

Iron–silver oxide nanoadsorbent synthesized by co-precipitation process for fluoride removal from aqueous solution and its adsorption mechanism

“…Structural analysis of an adsorbent and the information of various functional groups in the adsorbent were conveyed by Fourier transform infrared spectroscopy with spectral grade KBr in an agate mortar (FTIR, FTS-165, BIO-RAD, USA). The amount of Fluoride adsorbed onto the prepared MBON and the removal percentage (%) was calculated through the equation (1) or (2): The binding energies of the elements and specific functional groups before and after adsorption were obtained by using X-ray Photoelectron Spectroscopy with a monochromatic Al K-alpha X-ray source (1486.6 eV) (XPS, AXIS 165 (Kratos)).…”

“…Linear equations of isotherm models following from below formula: q e =k F (C e ) 1/n (10) q e =(q m k L C e )/(1+k L C e ) (11) q e =q m ln K T +q m ln C e (12) ln q e = ln q m −Dε 2 (13) Where, K F ((mg/g) (L/g) 1 Fig.11 presents the isotherms resulted of the Fluoride adsorption onto Fe-Ag MBON. Langmuir, Freundlich, Temkin and Dubinin-Radushkevich models used to investigate the behavior of Fluoride sorption and determine the maximum adsorption capacity of Fe-Ag MBON at room temperatures in 10 mg/L initial concentration.…”

“…Fluoride (F − ) has been recognized as one of the serious problem in surface/ground water [1].Different minerals (e.g., fluorite, biotites, topaz) are the natural geological sources of Fluoride which can be released into the groundwater [2]. Moreover various industries such as glass and ceramic production, fertilizer and semiconductor manufacturing are also contributing in fluoride pollution to a large extent.…”

Controllable synthesis of mesoporous alumina with large surface area for high and fast fluoride removal

“…The solution pH is extremely important for fluoride removal in solid/aqueous separation process, since it determines the adsorption potential at adsorbent-water interface and is related to the pH zpc (the pH point of zero charge) of the adsorbents [41]. Therefore, the fluoride adsorption onto MA at pH values ranging from 3 to 11 was investigated systematically when the initial fluoride concentration was maintained at 60 mg L -1 .…”

Enhancement in copper ion removal by PPy@Al2O3 polymeric nanocomposite membrane

“…high adsorption capacity, hydrophilicity and resistance to chemical agents [22][23][24][25][26][27], in this study, alumina nanoparticles [21]. Moreover, as a heavy metal, copper ions might be considered as a representative for bunch of heavy metals.…”