Sequential adsorption experiments were performed to determine the kinetics of polymer displacement. Protiopolystyrene (PSI and deuterio-cis-polyisoprene (PI) were allowed to adsorb sequentially at 12 O C , from dilute solution in carbon tetrachoride, onto a single surface of oxidized silicon. Whereas the net surface excess equilibrated rapidly, the individual populations of PS and PI equilibrat...

The rate of reaction of trace metals between soils and solutions is important in predicting trace metal behavior as equilibrium may not be attained. Although chemical equilibrium models are commonly used for soil systems, there has been less progress in developing predictive kinetic models. Kinetics of Zn adsorption/desorption have been modeled based on the linear adsorption isotherm assumption...

This study considers desorption kinetics for 12 field-aged polycyclic aromatic hydrocarbons (PAHs) desorbing from size- and density-fractionated sediments collected from two locations in the New York/New Jersey Harbor Estuary. Desorption kinetics for PAHs with a log octanol-water partition coefficient greater than 6 were well-described by a one-domain diffusion model that assumes that PAHs are ...

Methods by which experimental measurements of thermal desorption can be applied in astrophysical environments have been developed, using the sublimation of solid methanol as an example. The temperature programmed desorption of methanol from graphitic, amorphous silica and polycrystalline gold substrates was compared, with the kinetic parameters of desorption extracted by either a leading edge a...

The fate of micropollutants throughout wastewater treatment systems is highly dependent on their sorption interactions with sludge matter. In this study, both the sorption and desorption kinetics of polycyclic aromatic hydrocarbons (PAHs) in activated sludge were shown to be very rapid in comparison to biodegradation kinetics. It was concluded that PAH transfer does not limit their biodegradati...

Mobility of dissolved organic matter (DOM) strongly affects the export of nitrogen (N) and phosphorus (P) from soils to surface waters. To study the sorption and mobility of dissolved organic C and P (DOC, DOP) in soil, the pH-dependent sorption of DOM to samples from Ap, EB, and Bt horizons from a Danish agricultural Humic Hapludult was investigated and a kinetic model applicable in field-scal...

The effects of temperature on Cs+ sorption and desorption were investigated in subsurface sediments from the U.S. Department of Energy Hanford Site. The site has been contaminated at several locations by the accidental leakage of high-level nuclear waste (HLW) containing 137Cs+. The high temperature of the self-boiling, leaked HLW fluid and the continuous decay of various radionuclides carried ...

In this work, adsorption kinetics were investigated in order to remove the acid blue 62 off the aqueous solutions using mesoporous silicate SBA-15 loaded with tannic acid (tannin-SBA-15). Nitrogen adsorption and desorption test (BET), X-ray diffraction (XRD) and Fourier transform infra-red spectroscopy (FT-IR) analysis characterize synthesized composite. The impacts of some parameters such as P...

We present a study on the kinetics of oxygen adsorption and desorption from single-wall carbon nanotube ~SWNT! and highly oriented pyrolytic graphite ~HOPG! samples. Thermal-desorption spectra for SWNT samples show a broad desorption feature peaked at 62 K, which is shifted to a significantly higher temperature than the low-coverage desorption feature on HOPG. The low-coverage O2 binding energy...

Collision experiments between two different molecules both oriented with their axis are presented: The kinetics of the CO desorption and NO sticking probability by oriented NO has been investigated using supersonic molecular beam and work function techniques. The work function measurements exhibit mainly molecular adsorption of NO on a CO precovered Ni( 100) surface at T=300 K. The desorption a...