Amorphous hydrous manganese oxide (HMO) is an important mineral in soils and sediments influencing the mobility and bioavailability of metal contaminants. In this study, nickel and lead sorption to discrete HMO and HMO-coated montmorillonite was investigated mechanistically. The effect of pH and concentration revealed that when normalized to the mass of oxide present, the HMO-coated montmorillo...

The adsorption process is an alternative treatment method used to remove heavy metals of industrials effluents. In the present paper, sorption processes nickel (II), copper (II) and lead in aqueous solutions, utilizing montmorillonite like substrates, including isotherms single metal solutions were studied. According X ray diffraction principal constituent quartz (SiO2) that surface area create...

Sorption characteristics of phenanthrene (PHE) were studied on eight soils with organic carbon contents spanning over an order of magnitude using phase distribution relationships (PDRs) at 1 h, 48 h, and 720 h contact times. A new algebraic method was employed to describe the sorption characteristics at different time intervals (between 1 h and 48 h, and 1 h and 720 h). It was found that nonlin...

In this study kinetic investigations were combined with X-ray Absorption Fine Structure (XAFS) measurements to determine Ni sorption processes on pyrophyllite, gibbsite, and montmorillonite over extended time periods (min-months). The kinetic investigations revealed that Ni sorption reactions (pH 5 7.5, [Ni]initial 5 3 mM, I 5 0.1 M (NaNO3)) were initially fast (8–35% of the initial Ni was remo...

In situ chemical oxidation is a commonly applied soil and groundwater remediation technology, but can have significant effects on soil properties, which in turn might affect fate and transport of organic contaminants. In this study, it was found that oxidation treatment resulted mainly in breakdown of soil organic matter (SOM) components. Sorption of naphthalene and phenanthrene to the original...

Nonhydrolyzable organic carbon (NHC) and sorption isotherms of phenanthrene (Phen) on six size-fractionated NHC fractions in two sediments from the Pearl River and Estuary, South China, were investigated. It was found that NHC including ancient organic carbon, black carbon, resistant aquatic organic carbon, and aged soil organic carbon consists mainly of aliphatic and aromatic carbon using 13C ...

make better predictions about the mobility of contaminants, it is critical that time-dependent metal sorption To improve predictions of the toxicity and threat from Pb contamiand desorption behavior on soil be understood, as well nated soil, it is critical that time-dependent sorption and desorption behavior be understood. In this paper, the sorption and desorption as the mechanism of the sorpt...

This study investigates the dissolution, sorption, leachability, and plant uptake of tungsten and alloying metals from canister round munitions in the presence of model, well characterized soils. The source of tungsten was canister round munitions, composed mainly of tungsten (95%) with iron and nickel making up the remaining fraction. Three soils were chosen for the lysimeter studies while fou...

This study compared the abilities of two low-cost materials: a dried activated sludge and sunflower leaves to remove cadmium from aqueous solutions. Kinetic data and equilibrium sorption isotherms were measured in batch conditions. Kinetics of cadmium sorption was time contact and initial cadmium concentration dependent. The cadmium uptake of these two low-cost materials was quantitatively eval...

t The effect of sesquioxidic i i ic gravels (>2 mm size fraction) on phosphorus sorption by two gravelly lateritic soils was investigated by phosphorus sorption experiments, X-ray diffraction, ti , autoradiography and electron microscopy. In one soil the abundance and size of gravels l decreased downslope. As the gravel content of both soils increased (13-61%), ), the proportion of large (>8 mm...