in this study, the batch equilibrium method was used to conduct metribuzin adsorption/desorption experiments with eight soils from different regions of iran. the results indicated that the organic carbon (oc) content, clay content, cation exchange capacity (cec), and ph had a combined effect on the metribuzin adsorption on soil. under the experimental conditions, the adsorption amount of metrib...

The present study examined the adsorption of silver ion in aqueous solution onto natural clinoptilolite zeolite from Futatsui Mine, Akita Prefecture, Japan. The effects of various parameters, i.e., solution pH, adsorbent dosage, adsorption time, silver ion solution concentration, and temperature, on silver ion adsorption process onto clinoptilolite were examined. Additionally, the thermodynamic...

Adsorption characteristics of potentially toxic metals in single- and multi-metal forms onto ferronickel slag were evaluated. Competitive sorption of metals by ferronickel slag has never been reported previously. The maximum adsorption capacities of toxic metals on ferronickel were in the order of Cd (10.2 mg g(-1)) > Cu (8.4 mg g(-1)) > Zn (4.4 mg g(-1)) in the single-metal adsorption isotherm...

We report the density-functional calculations of NO2 adsorption on single-walled carbon nanotube walls. A single molecular adsorption was endothermic with an activation barrier, but a collective adsorption with several molecules became exothermic without an activation barrier. We find that NO2 adsorption is strongly electronic structure- and strain-dependent. The NO2 adsorption on metallic nano...

The contribution of variable grain sizes to uranium adsorption/desorption was studied using a sediment from the US DOE Hanford site. The sediment was wet sieved into four size fractions: coarse sand (1-2 mm), medium sand (0.2-1 mm), fine sand (0.053-0.2 mm), and clay/silt fraction (<0.053 mm). For each size fraction and their composite (sediment), batch and flow-cell experiments were performed ...

a type of novel hypercross-linked fiber adsorbent was obtained by sulfonation and cross-linking reaction of polypropylene fiber grafted styrene-divinylbenzene. the aim of the fiber sulfonation and cross-linking method was to prepare rigid three dimensional networks in the entire fiber and change the ion exchange capacity of fiber. the hypercross-linked fiber adsorbent possesses a principally di...

Many important industrial separation processes based on adsorption operate close to saturation. In this regime, the underlying adsorption processes are mostly driven by entropic forces. At equilibrium, the entropy of adsorption is closely related to the enthalpy of adsorption. Thus, studying the behavior of the enthalpy of adsorption as a function of loading is fundamental to understanding sepa...

BACKGROUND In order to remove heavy metals, water treatment by adsorption of zeolite is gaining momentum due to low cost and good performance. In this research, the natural mordenite was used as an adsorbent to remove lead ions in an aqueous solution. METHODS The effects of adsorption temperature, time and initial concentration of lead on the adsorption yield were investigated. Response surfa...

the work focuses on the removing of cu(ii) from aqueous solution by linde f(k) zeolite. the zeolite is synthesized from fly ash by hydrothermal process. the adsorption experiments discuss several factors including the optimal solution ph, zeolite dosage, adsorption temperature, adsorption kinetics and adsorption isotherm equation. the results show that, the optimal solution ph is 6 and the effi...

The adsorption of polymers to surfaces is crucial for understanding many fundamental processes in nature. Recent experimental studies indicate that the adsorption dynamics is dominated by non-equilibrium effects. We investigate the adsorption of a single polymer of length N to a planar solid surface in the absence of hydrodynamic interactions. We find that for weak adsorption energies the adsor...