Hydrolytic adsorption

Carbon Dioxide Adsorption on Dried Polymer. Other unexpected interactions of these hydrolytic polymers have been noted previously during the measurement of infrared spectra of dried Pu(IV) polymers (like those used for diffraction studies). Vibrational bands first attributed to nitrate ion were observed in samples exposed to room air however, these bands were not present in samples prepared under nitrogen atmospheres (see Fig. 4) (6). Chemical analyses established enough carbon in the exposed samples to confirm the assignment of the extraneous bands to the carbonate functional group... 

In addition to the mobility control characteristics of the surfactants, critical issues in gas mobility control processes are surfactant salinity tolerance, hydrolytic stability under reservoir conditions, and surfactant propagation. Lignosulfonate has been reported to increase foam stability and function as a sacrificial adsorption agent (392). The addition of sodium carbonate or sodium bicarbonate to the surfactant solution reduces surfactant adsorption by increasing the aqueous phase pH (393). 

Cook, M. A. and Wadsworth, M. E., 1957. Hydrolytic and ion pair adsorption processes in flotation, ion exchange and corrosion. In Proceedings of the 2nd Inter. Congr. Surf. Activity. Butterworth Co. Publisher, London, 3 228 - 242... 

Similar effects were observed by Stigter e< al. (185) with silica and aluminum chloride. The assumption of hydrolytic adsorption is supported by an observed increase of conductivity upon addition of silica to aluminum chloride solutions. Kautsky and Wesslau (240) observed hydrolytic adsorption of Th + ions. The reaction scheme given above is a simplification since, in reality, solutions of basic iron or aluminum salts contain polynuclear complexes. The size of the aggregates depends on pH and concentration. Chromatographic separation of various metal ions on silica gel columns was first described by Schwab and Jockers (241). The role of hydrolytic adsorption in column chromatography on silica gel was stressed by Umland and Kirchner (242). The use of this technique in analytical separations was investigated in detail by Kohlschiitter and collaborators (243-246). An application to thin-layer chromatography was described by Seiler (247). 

The predominant oxidation stale of the element is (V). There is some evidence that the (IV) state is obtained under certain reduction conditions. When the pentapositive form is not in the form of a complex ion it may exist in solution as PaC>2+. The compounds are very readily hydrolyzed in aqueous solution yielding aggregates of colloidal dimensions, thus showing marked similarity to niobium and tantalum in this respect. These properties play a dominant role in the chemical properties of aqueous solution, because the element is so easily removed from solution by hydrolysis and adsorption Protactinium coprecipilates with a wide variety of substances, and it seems likely that the explanation for this lies in the hydrolytic and adsorptive behavior. 

Temperature generally determines the position of the dyeing equilibrium, which at room temperature is shifted strongly toward adsorption on the fiber. At higher temperature (usually 80-95 °C) the equilibrium is attained more rapidly. The temperature dependence of the maximum degree of exhaustion is dye-specific. The same applies to hydrolytic stability, especially in high-temperature processes. 

Adsorption of Inorganic Ions and their Hydrolytic Products Due to Mineral... 

If a mineral surface becomes hydrophobic as a result of adsorption of a hydrolytic product of the collector, i.e. a nondissociated component, the modified Langmuir isotherm gets the form... 

System 1. Under ideal conditions the adsorption of a surfactant into the EDL proceeds as described in Chap. 3. The border of efficiency of anionic and cationic surfactants is IP or PZC, as follows from the correlation of e.g. adsorption density, potential and notability are dependent on pH [e.g. 44,129,167,174-176]. The course of such an adsorption is shown in Fig. 15. If H+ or OH" react with the surface of one mineral the released ions or their hydrolytic products can adsorb on unequally charged surface of the other mineral and cause an activated adsorption of the surfactant, or they can inhibit the adsorption, as shown on the schemes ... 

System 2. The presence of polyvalent lattice ions in the system containing minerals with PDIH+ and OH- leads to their specific adsorption in the EDL and is often accompanied with a change in IP and PZC provided the surface charge has the opposite sign of that of the adsorbing lattice ion. This leads to an inhibition or activation of the mineral surface as shown in Fig. 16179). The same is true for a hydrolytic product of lattice ions exhibiting a stronger surface activity than non-hydrolyzed ions, as a result of a combined electrostatic and chemisorptive effect. 

The molecular sieve behaviour of zeolites can be controlled by a hydrolytic process at elevated temperatures. Water vapour in contact with zeolite crystals at elevated temperatures results in a variation of the zeolitic adsorption characteristics. The amount of water vapour, the pretreatment temperature and the pretreatment time, can control the effect pore size of zeolites. It appears, that a steam treatment causes a cation migration and a cation hydrolysis of the exchangeable cations. However, the effect of steam on the adsorption behaviour of zeolites is influenced by the nature of the initial exchangeable cations. 

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