Salts selection criteria

In the meantime, we believe that the best prediction of the toxicity of an ionic liquid of type [cation] [anion] can be derived from the often well known toxicity data for the salts [cation]Cl and Na[anion]. Since almost all chemistry in nature takes place in aqueous media, the ions of the ionic liquid can be assumed to be present in dissociated form. Therefore, a reliable prediction of ionic liquids HSE data should be possible from a combination of the loiown effects of the alkali metal and chloride salts. Already from these, very preliminary, studies, it is clear that HSE considerations will be an important criterion in selection and exclusion of specific ionic liquid candidates for future large-scale, technical applications. 

Leachability of a waste form is perhaps the most important criterion in considering accident situations. In the absence of salts, some of our cement products may approach the low leachability of glass. After experimenting with several methods for measuring leach rates, we selected the... 

The selectivity of the method is given first by the ability to stay dissolved in a solution containing tartrate, second by the color of the sulfide precipitate, and finally by the fact that the sulfide salt dissolves in sodium hydroxide. The first property distinguishes it from bismuth(III) and the other cations forming insoluble oxides in neutral or alkaline solutions. But since the test does not show that a precipitate is formed in pure water, which dissolves when tartrate is added, all water-soluble cations are not excluded. So it should be viewed as a trick to facilitate dissolution only and not a part of the identification. The color of the sulfide precipitate is unique, and it is the most important criterion for a positive identification if there is any doubt when judging the result, preparing a positive control would be constructive. The solubility of the sulfide salt in sodium hydroxide is a characteristic shared with, for example, the sulfide salt of arsenate, and in classic inorganic separation the sulfide precipitate solubility in hydrochloric acid or polysulfide is used instead. " ... 

Criteria for selection of a molten salt for transport of heat should inelude criteria to assure ehemical plant safety. In most cases, this criterion is not expected to have a significant impact on the choice of molten salt. The transport of heat imposes two technical criteria on the choice of the salt (1) thermally stable at very high temperatures and (2) compatible with the materials of construction used for piping and heat exchangers. These criteria require selection of fluoride salts that are thermodynamically very stable. This required characteristic also makes exothermic chemical reactions with chemical process reagents unlikely in practical systems. 

The present publication reports on attemps made to prepare Y zeolites containing iron species via solid-state ion exchange between some iron(ll) salts (chloride, oxalate, and acetate, resp.) and NH4-Y zeolites. The formation of ammonium salts easily removable from the product after the exchange by thermal decomposition was the main criterion for the selection of the particular iron salts as reactants. 

The efficiency of a surfactant in platelet exfoliation and interfacial bonding should be considered as the main criterion for its selection. However, it is advisable to select a surfactant with respect to its thermal stability a well. The number and length of alkyl chains, type of counterion, and class of amine (or ammonium salt) - primary, secondary, or tertiary - were considered important parameters influencing the thermal stability of nanocomposites. 

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