Diphenyls, adsorption process

Adsorption of Disulfides and Related Compounds Adsorption and further electrode reactions of different disulfides at gold electrodes depend on chemical properties of the adsorbates. It has been evidenced in some papers that at least for some disulfides, adsorption process involves the cleavage of the S—S bond. Adsorption of diphenyl disulfide on a polycrystalline gold electrode has been studied in detail by Borsari etal. [166]. They have proposed the mechanism of adsorption shown in Scheme 1 ... 

In adsorption TLC, selectivity is mostly determined by the developing solvent system, whereas in RP-TLC the selectivity is determined primarily by the reversed-phase support and degree of carbon loading on the silica gel base. It should be kept in mind that the coating material of RP-TLC plates will always contain a certain amount of underivatized silanols that will confer to the plates some adsorptive and ionic characteristics that affect selectivity. It is, therefore, erroneous to think that all RP-Q, C8, C18, cyanopropyl, and diphenyl materials will behave similarly and it is strongly suggested that, in an optimization process, an investigator should experiment with plates from different suppliers. 

Surfactant adsorption on the reservoir surface is another important factor to be considered when using foams in EOR processes is discussed in [258]. Adsorption experiments with surfactants of different structures were performed on cores of a number of materials (quartz, sandstones, kaolin, calcite and others), both clean and modified (impregnated) with hydrocarbons of various structure ( light oil, high-viscosity oil, asphaltenes). Minimum adsorption, as well as maximum oil recovery based was observed when using amphoteric surfactants as well as surfactant mixtures, e.g. diphenyl ether disulfonate - a-olefin sulfonate (DPES-AOS). 

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