Anion Adsorption Behavior

The adsorption of sulfate was confirmed by radiotracer technique as shown in Fig. 14, which clearly shows that the sulfate adsorption feature depends on crystal faces, as reviewed in Ref. 17. 

Sulfate adsorption on Pt(lll) was investigated by thermodynamic treatment of the Gibbs excess, which is based on the Frumkin treatment.The above cyclic voltammogram feature at Pt(lll) in sulfuric acid solution was also thought to be due to the adsorbed sulfate.  

are suggested to undergo a redox adsorption/desorption process in which ions are always involved. 

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Hideaki, I., Junji, N., Yuzuru, I. and Tokuzo, K. (1987) Anion adsorption behavior of rare earth oxide hydrates. The Chemical Society of Japan, 5, 807-13. 

In this contribution, we present new results of a cychc voltanunetiy study of the influence of (CeHglads on Hypo and on anion adsorption at the Pt(l 11) electrode in aqueous HCIO4 and H2SO4, and relate them to analogous studies at Pt(110) and Pt(lOO) electrodes in aqueous H2SO4. Perchlorate anions are known to be less strongly adsorbed on Pt than bisulfate or sulfate anions thus, the cychc voltanunetiy behavior in the two electrolytes is expected to reveal important differences. 

Fujiwara, M., Matsushita, T., Kobayashi, T., Yamashoji, Y., and Tanaka, M., Preparation of an anion-exchange resin with quaternary phosphonium chloride and its adsorption behavior for noble metal ions, Anal. Chim. Acta, 274, 293, 1993. 

HYDROXYETHYL CELLULOSE ADSORPTION BEHAVIOR IN MULTIVALENT ANION SOLUTIONS... 

Both uncalcined and calcined LDHs have also been used as sorbents for decontamination of radioactive wastewater [150,151]. For example, Toraishi et al. [151] reported the adsorption behavior of lOs" in radioactive waste-water by LDHs with interlayer or NOs" anions. It was found that the... 

The above results show that BTA, PVI-1 and UDI behave differently in the two pH solutions tested in this study. The differences are probably related to the form of the Inhibitor, for example BTA takes on a cationic, anionic, or neutral form depending on the pH [333 This may affect the solubility of the cast films, adsorption behavior, reactions of the inhibitor at the electrode, and the solubility of any subsequent reaction products. The BTA molecule (pK.sO.44, pK s8.2) is soluble in all pH solutions in all forms l33.]. The neutral form is predominant in both 0.1M... 

It is well known that the shape of the curve depends on the nature of the anion(s) present in the system. In reality, there is an overall behavior reflecting simultaneous H/O and anion adsorption. 

Innocenti et al. have studied the kinetics [101] of two-dimensional phase transitions of sulfide and halide ions, as well as electrosorption valency [102] of these ions adsorbed on Ag(lll). The electrode potential was stepped up from the value negative enough to exclude anionic adsorption to the potential range providing stability of either the first or the second, more compressed, ordered overlayer of the anions. The kinetic behavior was interpreted in terms of a model that accounts for diffusion-controlled random adsorption of the anions, followed by the progressive polynucleation and growth. 

As for the effect of anionic group, there are a number of reports dealing with the antithrombogenic behavior of sulfonate-modified surfaces of segmented polyurethane (SPU). An interesting feature of the adsorptive behavior of fibrinogen on these material surfaces will be discussed in Sect. 4.1. 

These applications require a good knowledge of the nature and magnitude of interactions between nucleic acids and polymer particles. To that purpose, many systematic studies were carried out by different authors and in this lab on the adsorption behavior of various nucleic acids onto various type latex microspheres, mostly cationic and anionically-charged polystyrene or hydrophilic (i.e. poly[N-isopropylacrylamide]) latex particles. 

Application of the electric double layer theory to soil minerals at a quantitative level is difficult because soil mineral surfaces at the microscopic scale are not well defined, that is, they are neither perfectly spherical nor flat, as the double layer requires. However, application of the double layer theory at a qualitative level is appropriate because it explains much of the behavior of soil minerals in solution, for example, dispersion, flocculation, soil permeability, and cation and/or anion adsorption. When equilibrium between the counterions at the surface (near the charged surface) and the equilibrium solution is met, the average concentration of the counterions at any... 

In their recent papers, Guiochon and co-workers are essentially advocating for the domination of the first process [158-160]. They are explaining the counteranion effect on the basis of the formation of a neutral ionic complex, followed by its adsorption on the hydrophobic stationary phase. Similarity in adsorption behavior of anionic and cationic species is interpreted as a confirmation of their adsorption in the form of neutral complexes. 

Anion-exchange adsorption behavior of ten metal ions in mixtures of HCl and HCIO4 was studied By forced-flow chromatography and automatic UV detection of the eluent stream trace amounts could be determined ... 

The purpose of this study was to investigate the anionic exchange behavior of neptunium(V) in sulfate-sulfuric acid, because neptunium is often present as a contaminant during the separation of other actinides (l ). Sulfuric acid systems are seldom utilized in industrial processes, but are often used as part of a laboratory analytical procedure. Literature on neptunium in HC101, HC1, HC1-HF, and HNO3 is quite complete, but the information on the H2S0l system is sketchy at best. There is one report 2) that neptunium(V) is adsorbed strongly on Dowex 2 resin from 0.1 IT to 1 IT H SOip Our measurements indicate that there is very little adsorption of Np(V) on Dowex 1 resin even at low concentrations of sulfate-sulfuric acid. We believe the differences in chemical structure of the two resins are not sufficient to explain the disparity in adsorption. 

On the other hand, the elution order for anions such as bromide and nitrate, for which the separation is mainly based on a different adsorption behavior (see Section 3.2), is governed by the hydiophobicity of the exchange function. In this respect, a... 

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