We report a study on the desorption properties, crystallography and chemical state of MgH2 and 1 mol% Nb2O5 ball-milled composites. Desorption temperatures of the composites decreased with increase of ball-milling time. Size of MgH2 crystallites decreased during ball-milling. Reduction of Nb2O5 after ball-milling was confirmed by tracing the chemical state of Nb and was further supported by TEM...

The effective management of sewage sludge materials in an environmentally and economically acceptable way is through the pyrolytic conversion of the sludge to biochar and its use for agricultural purposes. The aims of this work were: (1) to assess the effect of biochar prepared from sewage sludge at two different temperatures (350 ºC and 650 ºC) on the adsorption/desorptio...

Polycyclic aromatic hydrocarbons (PAHs), abundant in mixed contaminant sites, often coexist with heavy metals. The fate and remediation of PAHs depend heavily on the sorption and desorption behavior of these contaminants. The sorption behavior can in turn be highly affected by certain soil components and properties, such as soil organic matter (SOM) and the presence of heavy metals. Through rev...

Adsorption and desorption of atrazine and its metabolites in vegetated filter strip soil (VFS) has not been evaluated, yet these data are needed to predict the transport of these compounds through the VFS. Adsorption and desorption parameters for atrazine, desethylatrazine (DEA), deisopropylatrazine (DIA), and hydroxyatrazine (HA) were compared between a cultivated Houston Black clay (CS) and a...

The bioavailability and ultimate fate of heavy metals in the environment are controlled by adsorption-desorption process. Batch equilibrium experiments were performed to assess the effects of pH and low molecular weight organic acids (LMWOAs) on competitive adsorption and desorption of cadmium and lead in paddy soils from China. The results indicated that both soils exhibited greater sorption c...

An in-situ derivatization thermal desorption method followed by gas chromatography and time-of-flight mass spectrometry (IDTD-GC-TOFMS) was developed for determination of polar organic compounds together with non-polar compounds in one measurement. Hydroxyl and carboxyl groups of compounds such as anhydrous sugars, alcohols and phenols, fatty acids and resin acids are targets of the derivatizat...

An understanding of sorptive processes is key to describing the fate of chlorpyrifos [O,O-diethyl-O-(3, 5, 6-trichloro-2-pyridyl) phosphorothioate] in aquatic environments. The objectives of this study were to evaluate isotherms for adsorption and desorption of chlorpyrifos on colloidal materials and to advance understanding of interaction mechanisms between chlorpyrifos and colloidal materials...

Directly measuring the rate of a surface chemical reaction remains a challenging problem. For example, even after more than 30 years of study, there is still no agreement on the kinetic parameters for one of the simplest surface reactions: desorption of CO from Pt(111). We present a new experimental technique for determining rates of surface reactions, the velocity-selected residence time metho...