Melting oxidizers

Does not melt. Oxidizes slowly m air at temperatures above 600 F (3I64C), Cannot be dyed,... 

Because refractory bricks are nearly always applied in high temperature environments and in direct contact with oxygen from the air, high-melting oxides are preferably used as raw materials (table 11.3.2). 

Pickup and Osteryoung investigated the polymerization of pyrrole in both the AlCl3/[C4py][Cl] molten salt [48] and the more conductive AlCl3/[C2mim][Cl] [49]. Synthesis of poly(pyrrole) is only possible in neutral melts. In basic melts oxidation of Cr to CI2 occurs before the monomer oxidation and in acidic melts no films are produced due to the formation of a 1 1 AlC -pyrrole adduct, as determined by NMR spectroscopy [50]. 

Table 4.93 Corrosion resistance of structural ceramics to fused salts, alkalis and low-melting oxides...

On the basis of their results, they put forward an "oxide interaction concept , according to which the friction and wear of bonded films, composites and simple transfer films of molybdenum disulphide are improved by the presence of low-melting oxides which either combine easily or form desirable eutectics with molybdenum oxides. Such a concept would provide valuable guidance to the development of better solid lubricants, but, as Buckley pointed out, the authors had in fact produced no evidence for the "oxide interaction" concept. The lower friction can in fact be explained by a reduction in the rate of oxidation, since the films exhibiting lower friction had all been run at some stage in air. 

The combustion synthesis technique consists of bringing a saturated aqueous solution of the desired metal salts and a suitable organic fuel to the boil, until the mixture ignites a self-sustaining and rather fast combustion reaction, resulting in a dry, usually crystalline, fine oxide powder. By simple calcination, the metal nitrates can, of course, be decomposed into melt oxides upon heating to or above the phase transformation temperature. 

In principle, these and many more high melting oxides are potential candidates for supports, However, the oxide must be amenable to colloidal preparations yielding high surface areas. If high dispersions are not needed, as in steam reforming, then less demanding preparational methods are sufficient. 

TABLE 2.2. High Melting Oxides Used as Suppons... 

Ideally, support materials should have no catalytic activity leading to undesirable side reactions. This is usually true for high melting oxides fired to give low surface area supports. However, colloidal hydrous oxides are usually acidic in nature. Alumina, for example, is dehydrated during preparation ... 

Oxygen Electrodes in Ionic Melts. Oxide Ion Donors... 

Oxygen electrodes in ionic melts. Oxide ion donors... 

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