Alkaline earth metals peroxides

A process that successfully removes filter-cake contains polysaccharide polymers and certain bridging particles and uses alkaline earth metal peroxides and zinc peroxide in an acidic aqueous solution [499,1239]. On soaking the filter-cake, a loosely adherent mass is left behind on the walls of the borehole. Thereafter, a wash solution in which the bridging particles are soluble is used to remove the remaining filter-cake solids from the sides of the borehole. 

Peroxide Breakers. Alkaline earth metal peroxides have been described as delayed gel breakers in alkaline aqueous fluids containing hydroxypropylguar [1238]. The peroxides are activated by increasing the temperature of the fluid. 

The superoxides are ionic soHds containing the superoxide, O - A comprehensive review of the superoxides was pubHshed ia 1963 (109) they are described ia Reference 1. Superoxides of all of the alkaU metals have been prepared. Alkaline-earth metals, cadmium, and 2iac all form superoxides, but these have been observed only ia mixtures with the corresponding peroxides (110). The tendency to form superoxides ia the alkaU metal series iacreases with increasing size of the metal ion. 

The heavier alkaline earth metals Ca, Sr, Ba (and Ra) react even more readily with non-metals, and again the direct formation of nitrides M3N2 is notable. Other products are similar though the hydrides are more stable (p. 65) and the carbides less stable than for Be and Mg. There is also a tendency, previously noted for the alkali metals (p. 84), to form peroxides MO2 of increasing stability in addition to the normal oxides MO. Calcium, Sr and Ba dissolve in liquid NH3 to give deep blue-black solutions from which lustrous, coppery, ammoniates M(NH3)g can be recovered on evaporation these ammoniates gradually decompose to the corresponding amides, especially in the presence of catalysts ... 

In addition to the oxides MO, peroxides MO2 are known for the heavier alkaline earth metals and there is some evidence for yellow superoxides M(02)2 of Ca, Sr and Ba impure ozonides Ca(03)2 and Ba(03)2 have also been reported. As with the alkali metals, stability... 

Note from Table 20.1 that several different products are possible when an alkali or alkaline earth metal reacts with oxygen. The product may be a normal oxide (O2 ion), a peroxide (022- ion), or superoxide (02 ion). 

Heating with the following solids, their fusions, or vapours (a) oxides, peroxides, hydroxides, nitrates, nitrites, sulphides, cyanides, hexacyano-ferrate(III), and hexacyanoferrate(II) of the alkali and alkaline-earth metals (except oxides and hydroxides of calcium and strontium) (b) molten lead, silver, copper, zinc, bismuth, tin, or gold, or mixtures which form these metals upon reduction (c) phosphorus, arsenic, antimony, or silicon, or mixtures which form these elements upon reduction, particularly phosphates, arsenates,... 

Production of Peroxides of Alkaline Earth Metals Ca02, Sr02, Ba02 , NASA No N65-31257 (1965) CA 66,121576 (1967)... 

Vol nov, I. I. Peroxides, superoxides, and ozonides of alkali and alkaline earth metals. New York Plenum Press 1966. 

Oxidized impurities in the fuel are also adsorbed and oxidized by the reactor which has U.S. Patent 6,068,943. Suitable oxygen-containing compounds include peroxo monosulfuric acid, a peroxide of the alkali or alkaline earth metals in an acid solution. These oxygen-containing compounds can be catalytically decomposed to release oxygen. Liquid... 

Alkaline earth metals, Group II + 2 Oxygen — 2 (except in peroxides)... 

Reaction with sulfuric acid yields monoperoxysulfuric acid. Reactions with many alkaline earth compounds yield peroxides of alkaline earth metals ... 

How can the oxides, peroxides, and hydroxides of the alkaline-earth metals be prepared What are the commercial names of calcium and barium hydroxide solutions How do the solubility, basic properties, and thermal stability of the hydroxides change in the series calcium-strontium-barium ... 

The other pathway leading to the formation ofoxogroups in the coordination sphere of the metal atom is provided by uncontrolled oxidation of the basic alkoxides such as alkali, alkaline earth metal, and quite probably the rare earth metal ones by oxygen dissolved in solvents and present in the atmosphere. The primary oxidation products are peroxides and hydroperoxides — M(OOR)n and M(OOH)n, whose decomposition gives water among the other... 

The common heavy metals do not form peroxides only the most strongly metallic elements such as the alkali and alkaline earth metals do so. For example, when sodium metal bums freely... 

A special group of inhibitors are those substances which suppress the decomposition of hydrogen peroxide in alkaline solutions, which are used for bleaching purposes or for preparation of addition compounds of hydrogen peroxide. Good stabilizers for such solutions are e. g. magnesium orthosilicate, water glass and phosphates of alkaline-earth metals. 

A similar but less complete trend appears in the reactions of the alkaline earth metals with oxygen. Treatment with excess 02 yields monoxides in the cases of beryllium, magnesium, and calcium barium, however, forms the peroxide, Ba02, whereas strontium gives a mixture of monoxide and peroxide. 

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