Salt protonic acids, molten

Electrolyte Potassium Polymer, proton Polymer Phosphoric acid Molten salt such as Ceramic as stabilized... 

Many years ago, L. F. Audrieth studied numerous reactions of amine hydrochloride salts. These compounds contain a cation that is a protonated amine that can function as a proton donor. Consequently, the molten salts are acidic and they undergo many reactions in which they function as acids. This behavior is also characteristic of ammonium chloride as well as pyridine hydrochloride (or pyridinium... 

In a search for an aprotic solvent for acidity function studies with (Li, Na, K) acetate eutectic at200°C (Na, K)SCN was suitably miscible however, even small concentrations (1 %) inhibited the known reaction of trimethylol-ethane, which probably requires proton abstraction by the acetate anion to form an alkoxide intermediate. Since haloacetates are weaker bases than acetates, these salts were considered for diluents. Potassium trifluoroacetate (mp 135-I37°C), reported to be the most stable member of the series, was prepared from potassium hydroxide and excess trifluoroacetic acid with vacuum drying and fractional recrystallization from absolute alcohol. DTA of the white crystalline product detected decomposition as low as 125°C. Since the molten salt decomposed with bubbling at I45-150°C, this effort was discontinued. 

As noted before, solubility of covalent organic compounds in molten salts seems to require proton interaction between acidic groups of the solute and anions of the solvent. For un-ionized solutes this may well involve structures analogous to the solvent-bridged ion-pair complexes postulated for concentrated aqueous solutions ... 

In contrast to inorganic molten salts, the fluidity of ionic hquids at room temperature permits their use as solvents for chemical reactions. Electrostatic properties and charge mobility in ionic hquids can play a distinctive role in chemical reactivity, as compared with neutral solvents. In particular, hydrogen and proton transfer reactions are likely to be sensitive to an ionic environment due to the hydrogen-bond acceptor ability of the anions. Such type of reactions are fundamental in acid-based chemistry and proton transport in solution. 

The second part treats the chemistry, structures and electrical properties of typical materials, from hydrogen bronzes to polymers via ice, hydroxides, acid sulphates, layer hydrates, inorganic ion exchangers, gels, porous media and mixed inorganic-organic polymers. These materials are compared with liquid and molten salt conductors, intercalated graphites and metal hydrides and have been chosen in order to illustrate the different behaviour of the proton it has electron-like properties in some oxides and hydrides, ion-like behaviour in some other oxides or liquid-state behaviour such as encountered in solution covered particles or pores of a gel. 

The values of the prirrrary medium effect of proton were used by Izmailov to con-stract the common acidity scale for protolytic solvents and for the solvents more basic than water having negative values of logy +, whereas for more acidic solvents these valuesarepositive. It is obviorrs that for the cafe of molten salts values of logy 2- will... 

There is nothing unusual about the acidic behavior of ammonium salts. In fact, any protonated amine can function as a proton donor. Because of this, many amine salts have been used as acids in synthetic reactions. If the chlorides are used, the amine salts are known as amine hydrochlorides. One of the earliest amine hydrochlorides studied with regard to its behavior as an acid is pyridine hydrochloride (pyridinium chloride), C5H5NH+C1. In the molten state, this compound undergoes many reactions of the type just shown. 

Nylon is the common name for polyamides. Polyamides are generally made from reactions of diacids with diamines. The most common polyamide is called nylon 6,6 because it is made by reaction of a six-carbon diacid (adipic acid) with a six-carbon diamine. The six-carbon diamine, systematically named hexane-1,6-diamine, is commonly called hexamethylene diamine. When adipic acid is mixed with hexamethylene diamine, a proton-transfer reaction gives a white solid called nylon salt. When nylon salt is heated to 250 °C, water is driven off as a gas, and molten nylon results. Molten nylon is cast into a solid shape or extruded through a spinneret to produce a fiber. 

In order to probe the intriguing catalytic behavior of benzoic acid, studies were conducted with the acid and the sodium salt, sodium benzoate, to determine the whether the protic nature of the catalyst was significant [31]. Complete dissociation of the acid in the molten trimer under reaction conditions was viewed as a matter of speculation, and the presence of protons did not provide any clear insight into the role of the benzoate ion. Sodium benzoate was safely assumed to be dissociated. The data recorded for both catalysts suggested similar kinetic behavior, which in turn implied that the potential degree of ionization of the catalyst does not play a role in the catalysis. 

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