0000000000527906
AUTHOR
L.s. Kostenko
Preparation and characterization of organofunctionalized bentonite clay bearing aminophosphonic groups in heavy metal uptake
Abstract Bentonite (Bnt) with covalently immobilized N-propylaminodi(methylenephosphonic) groups (Bnt-ADPA) was obtained through a two-step synthesis including aminosilanization and phosphorylation of resulting aminobentonite through Moedritzer-Irani reaction. The grafting of an aminosilane layer in the interplanar space of the bentonite was investigated by XRD, and the presence of N and P-containing groups was confirmed by FTIR, 31P and 29Si MAS NMR. The immobilization of the organic functional groups increased the interplanar distance in bentonite matrix at 52% that essentially improved filtration properties compared to raw bentonite. The number of surface acid groups was evaluated to 0.8…
Bentonites with grafted aminogroups: Synthesis, protolytic properties and assessing Cu(II), Cd(II) and Pb(II) adsorption capacity
Abstract Bentonites with grafted methylaminopropyl (NHCH3-Bent), aminopropyl (NH2-Bent), ethylenediaminopropyl (En-Bent) and diethylenetriaminopropyl (Dien-Bent) groups were synthesized by silylation procedure. The successful covalent grafting of silylating agents on the bentonite was confirmed by 29Si NMR, FTIR and thermal analysis. The effects of polar (ethanol) and non-polar (dioxane) solvents on grafting process were compared. The samples prepared in ethanol showed the increase of d001 value from initial 1.44 nm to 1.63–2.05 nm proportionally to the loading amount of grafted silane. However, an almost constant value of d001 (1.96–2.10 nm) was observed for all samples obtained in dioxane…