Electrolytic formation

Rainfall, besides wetting the metal surface, can be beneficial in leaching otherwise deleterious soluble species and this can result in marked decreases in corrosion rate . A recent survey of rainfall analyses for Europe has shown that, with the exception of the UK, the acidity and sulphate content of rainfall markedly increased in the period 1956 to 1966, pH values having fallen by 0 05 to 0-10 units per ann. The exception of the UK may be due to anti-pollution measures introduced in this period. However, even in the UK a pH of 4 is not uncommon for rainfall in industrial areas. The significance of electrolyte solution pH will be discussed in the context of corrosion mechanisms. The remaining cases of electrolyte formation are those in which it exists in equilibrium with air at a relative humidity below 100%. 

This concept may be invoked to account for electrolyte formation in microcracks in a metal surface or in the re-entrant angle formed by a dust particle and the metal surface. More importantly, it can also explain electrolyte formation in the pores of corrosion product and hence the secondary critical humidity discussed earlier. Ferric oxide gel is known to exhibit capillary condensation characteristic and pore sizes deduced from measurements of its adsorptive capacity are of the right order of magnitude to explain a secondary critical relative humidity as70 7o for rusted steel . 

PEO is found to be an ideal solvent for alkali-metal, alkaline-earth metal, transition-metal, lanthanide, and rare-earth metal cations. Its solvating properties parallel those of water, since water and ethers have very similar donicites and polarizabilities. Unlike water, ethers are unable to solvate the anion, which consequently plays an important role in polyether polymer-electrolyte formation. 

Bouroushian M, Kosanovic T, Loizos Z, SpyreUis N (2000) On a thermodynamic description of Se(IV) electroreduction and CdSe electrolytic formation on Ni, Ti and Pt cathodes in acidic aqueous solution. Electrochem Commun 2 281-285... 

According to Baranowski and subsequent authors, the electrolytic formation of NiH c is conditioned by factors such as the presence in the electrolyte of small amounts mol dm ) of a S, As,... 

As in the electrolytic formation of perdisulphuric acid, the first anodic product is the discharged HS04 ion, which by coupling then gives rise to perdisulphuric acid. If the metal perdisulphate is less soluble than the acid sulphate, it crystallises from the solution this is... 

In the electrolytic formation of heterocyclic systems the role of the current is to bring one or both of the reaction centers to a suitable oxidation state. These reactions may be classified in different ways here they are treated according to the type of bond formed. 

The previous chapters refer to electrolytic formation of one constituent of an essentially chemical initiating system. In this chapter the author would like to call attention to another type of electrolytic polymerization where catalytically active complexes are formed at the cathode and initiate polymerization. 

The procedures to be referred to in this chapter are electrolytic formation of initiator, electric field polymerization, and an extension of the method of electrodialysis, that have been only briefly reported in the literature. 

H. Dautzenberg, W. Jaeger, J. Kotz, B. Philipp, Ch. Seidel, D. Stscherbina, Poly electrolytes - Formation, Characterization and Application, Hanser Publishers, Munich, 1994. 

While the process at the cathode always ends finally in withdrawal of oxygen or in taking up of hydrogen, the number of possible reactions at the anode—aside from solution-phenomena, which are without interest here—is a much greater one. For, each ion which is capable of substituting can pass into the reactive state at the anode and produce reactions which cannot be numbered with the real oxidations. In the first place numerous substitutions can occur in difficultly oxidizable bodies, especially aromatic compounds, for instance the chlorination of phenols and phthale ins, nitration of acids, diazotizing of amines, etc. Substitution and oxidation processes often occur simultaneously, as in the electrolytic formation of iodoform from alcohol. 

Electrolytic formation of carbon-carbon bonds occurs in the reduction of ketones to pinacols, in the Kolbe synthesis, and in the hydrodimerization of activated double bonds. Of these only the last reaction has been used in the preparation of heterocyclic compounds. 

Electrolytic formation of finely dispersed bubbles (usually H2 and O2, from water electrolysis) can remove suspended particles from a liquid by floating them to the top. This solid matter can then be skimmed off from the top and subsequently treated. Much like electrodialysis, electroflotation is a process that concentrates the waste, which eventually needs to be treated and/or reused. It was estimated in 1980 that 20 electroflotation plants existed in the UK for treating industrial effluent [139]. Little to no information is available on the use of electroflotation for the decontamination of waste effluents in the USA. 

The amphiphilic pyrrole is a fairly specialized application of ultrasound for the formation of a multiphase electrolyte system, but a more general case of ultrasonic assistance in both electrolyte formation and subsequent electrolysis is given in a recent Japanese patent by Permelec Electrode [235] in which benefit is claimed by use of a hydrophobic electrode to electrolyze poor water-soluble materials under ultrasound an aqueous emulsion. 

According to Baranowski and subsequent authors, the electrolytic formation of Ni 11, is conditioned by factors such as the presence in the electrolyte of small amounts (<10 mol dm ) of a S, As, or Se compound [75], and the pH of the electrolyte. It has been stated in Ref. 73 that electrolytic hydriding of Ni failed in alkaline media. More recently, the validity of this statement was questioned by Bernardini etal. [76, 77[. According to [76, 77], considering of apparent similarity... 

---