Chloride adsorption

Kolics A, Thomas A E and Wieckowski A 1996 CI-labelled and electrochemical study of chloride adsorption on a gold electrode from perchloric acid media J. Chem. See. Faraday Trans. 92 3727-36... 

Gold, chloride, adsorption, magnetite, goethite, alumina, titanium dioxide, hydrometallurgy... 

Hughes, H. C., Linge, H. G. (1989). Kinetics of gold chloride adsorption onto fresh activated coconut carbon. 

Schofield RK, Samson HR (1954) Flocculation of kaolinite due to the attraction of opposite charged crystal faces. Discuss Faraday Soc 18 135-145 Schofield RK, Samson HR (1953) The defiocculation of kaolinite suspensions and the accompanying change-over from positive to negative chloride adsorption. Clay Miner BuU 2 45-51 Schulten HR (2001) Models of humic structures association of humic acids and organic matter in soils and water. In Qapp CE et al. Humic substances and chemical contaminants. Soil Science Society of America, Madison, Wl, pp 73-88... 

Analysis of PCBs. PCB residues in extracts of egg samples were enriched by using a combination of gel permeation chromatography on BioBeads S-X3 and 1 1 (v/v) cyclohexane. methylene chloride. Adsorption column chromatography on silicic acid was used to separate PCBs from other co-extractives and contaminants (15). 

Typical of the sort of data needed to determine whether additives affect the interface is that provided by a study of the influence of n-heptyl compounds on the gel structure of dispersions containing polar solids in nonpolar vehicles (70). The influence of the polar heptyl compounds on the fluidity of dispersions of rutile and a fine silica (HiSil) in a dibasic ester, Plexol 201, is shown in Fig. 7. Apparently, the more polar rutile adsorbs all except the chloride and in these cases thinning results. HiSil has a lower F value and adsorbs only the amine and alcohol preferentially. Greases prepared from the least polar solid, Aerosil, are also least influenced by these additives (or even by more complex ones). Measurements of the solution isotherms for HiSil and Aerosil reveal significant adsorption of heptyl alcohol, but no detectable chloride adsorption in the same concentration range. 

Sodium Chloride (Adsorption Indicator Method), It is described in the book of H.A. Laitinen, Chemical Analysis 5, McGraw-Hill, NY (i960), pp212—14 Reagents ... 

Schofield, R.K. and Samson, H.R., 1953. The deflocculation of kaolinite suspensions and the accompanying change over from positive to negative chloride adsorption. Clay Miner., 2 45-50. 

The reason for these discrepancies is quite probably to be ascribed to a strong dependence of the activity coefficient of /, f(rs)irs, upon E and rs at the high surface coverages employed for the estimate of l. In particular, I values obtained from Ms versus E plots at constant Es are affected by the potential dependence of the activity coefficient at constant rs (see Eq. 21) conversely, the l values obtained from the dependence of crM upon rs at constant E are affected by the 7s-dependence of the activity coefficient at constant E. These different dependences may have opposite effects on the l values obtained on the basis of the two alternative thermodynamic definitions. This may also explain the anomalously high l values for bromide and chloride adsorption on polycrystalline Ag obtained by Schmidt and Stucki16 from Ms versus E plots at constant Es. For this reason, at high surface... 

The perchlorate ions have been found to interact with the Ti02 films (but not with the unreduced anatase powder), forming relatively small amounts of chloride species (cf. Table 1). It seems probable that the latter spedes, arising from the reductive adsorption of the CIO4 ions, were not simply adsorbed but incorporated into the surface region of the Ti02 films, as no irreversible chloride adsorption could be detected from NaCl solutions. 

Perspectives. Ordered mesostnictured and mesoporous silica has been known for little more than ten years. Tremendous progress has been made with respect to precise control of the structure, texture, and chemical fimctionality of the surface of these materials. His lecture surveyed the synthesis of such materials, with a focus on organically ordered mesoporous materials. Quite a number of contributions dealt with amorphous fumed silica, its Physical-Chemical Features and Related Hazard Risk Assessment (M. Heinemann), the description of fractal aggregates (C. Batz-Sohn), and the Characterization of Size and Structure of Fumed Silica Particles in Suspension (F. Babick). E. Brendle reported on Adsorption of Water on Fumed Silica, and in a second paper he summarized research on Methylene Chloride Adsorption on Pyrogenic Silica Surfaces. 

Methylene Chloride Adsorption on Pyrogenic Silica Surfaces... 

Keywords pyrogenic silica, methylene chloride adsorption. Inverse Gas Chromatography, hydrophilic surface... 

In order to compare the effect of the surface hydroxyl groups and water contents on the methylene chloride adsorption process, various conditioning conditions were applied. The latter are... 

The samples were conditioned following the D160 protocol (conditioning at 160 °C, under dry carrier gas stream). The methylene chloride adsorption isotherms were determined on each sample and used to compute the BET surface area (5bet(CH2C12)), the corresponding BET constant (Cbet), and the adsorption energy distribution functions (AEDF). 

The surface energetic heterogeneity determination constitutes an additional aspect of the present study. This was performed by means of the methylene chloride adsorption energy distribution functions (AEDF) computation, relating the number of interactive surface sites to the desorption energy of each individual site. The latter are displayed in Fig. 1. 

The influence of physically absorbed water molecules on the methylene chloride adsorption and interaction capacity of silica will now be investigated. We generated, at 30 °C, three carrier gases having controlled percentages of moisture (RH%). The silica samples were equilibrated for several hours with these wet gases in order to achieve a constant yield of physically absorbed water. The... 

Arenz M, Stamenkovic V, Schmidt Tl, Wandelt K, Ross PN, Markovic NM (2003) The effect of specific chloride adsorption on the electrochemical behaviour of ultrathin Pd films deposited on Pt(l 11) in acid solution. Surf Sci 523 199... 

Some of the papers quoted propose a more or less direct interference of the promoters on the reaction mechanism, e g., a methylating action or an influence on methyl chloride adsorption. Of course, such actions cannot be excluded from a logical point of view and, moreover, it cannot be excluded that one promotor can act in more than in one way. 

The amount of acid used initially must be reduced to 25 mL of I + 5 hydrochloric acid for 0.5 g of gypsum sample, and the final volume made up to 400 to 450 mL. This acidity will allow the quick dissolution of pure as well as low grade gypsum samples and bring the final acidity to the level of 0.05 to 0. IN, which is most suitable for accuracy. This will also minimize the errors because of occlusion of chloride ions and barium chloride, adsorption of H and coprecipitation of barium chloride and Ca ions, and solubility of barium sulfate in acidic solutions. 

Figure 15. In situ STM images (60 nm x 150 nm) of Au(lll) electrode surface in 0.05 M H2SO4 + 5 mM NaCl solution, (a) electrode potential 0.25 V, no chlorides adsorption (b) electrode potential 0.70 V, chlorides adsorption (c) electrode potential 0.25 V, no chlorides adsorption (d) electrode potential 0.90 V, chlorides adsorption (e) electrode potential 0.25 V, no chlorides adsorption. Potentials v.v. Pd-H electrode. Reprinted from Ref. 125, Copyright (1998) with permission from Elsevier.

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