Magnesium formate decomposition

The addition of nickel formate to magnesium formate significantly reduced the decomposition temperature [1151]. The acceleratory period characteristic of the decomposition of pure Mg(HC02)2 was eliminated and the value of E was substantially diminished. For the double (Zn,Ba) and (Cu,Ba) formates, the rate of decomposition [1152] of the less stable component (Zn or Cu) was slower and that of the more stable component (Ba) more rapid than the values characteristic of pure preparations of these substances. 

Belkbir, L., Joly, E. and Gerard, N. (1981) Comparative-study of the formation-decomposition mechanisms and kinetics in LaNi5 and magnesium reversible hydrides. International Journal of Hydrogen Energy, 6, 285-294. 

The affinity for oxygen of the metal involved determines whether reactions of type I or type II occur. Nickel formate produces nickel, magnesium formate produces magnesium oxide. Of special interest to us, however, is the extent to which reactions of type a or b occur, and whether the Ia/Ib or the Ila/IIb ratio is in any way related to the selectivity of the catalytic decomposition of formic acid on the metals and oxides in question. Furthermore it is worth while to investigate whether the stability of the bulk formates (e.g., the decomposition temperature) bears a relation to the catalytic activity of the corresponding metals or oxides. 

Discernible endothermal effect for magnesium carbonate decomposition is evident even at a dolomite content of 0.3%. The activation energy of limestone decomposition has a strong bearing on the clinker formation. The de-carbonation of limestone varies, depending on the type, particle size, and impurities. DTA has been used to test the effect of fineness on the disassociation of limestones from different sources. It has been concluded that the finer the grain sizes and more the impurities, the lower is the activation energy. 

For all three halates (in the absence of disproportionation) the preferred mode of decomposition depends, again, on both thermodynamic and kinetic considerations. Oxide formation tends to be favoured by the presence of a strongly polarizing cation (e.g. magnesium, transition-metal and lanthanide halates), whereas halide formation is observed for alkali-metal, alkaline- earth and silver halates. 

Diverse thermogravimetric results can be obtained from samples with different pre-histories for example, TG and DTG curves showed that magnesium hydroxide prepared by precipitation methods has a different temperature of decomposition from that for the naturally occurring material.32 It follows that the source and/or the method of formation of the sample should be ascertained. 

The formation of Grignard reagents takes place at the metal surface. Reaction commences with an electron transfer to the halide and decomposition of the radical ion, followed by rapid combination of the organic group with a magnesium ion.1 It... 

B. Vigeholm, J. Kj0Uer, B. Larsen, A.S. Pedersen, Formation and decomposition of magnesium hydride, J. Less-Comm. Metals 89 (1983) 135-144. 

Magnesium sulfate undergoes three important types of reactions in aqueous solutions double decomposition, double salt formation, and formation of oxysulfate cements. Many insoluble magnesium salts may be precipitated out by double decomposition reactions ... 

One of the emerging technologies that is showing great promise is the use of hydrated mineral fillers such as aluminium and magnesium hydroxides, as such materials can provide high levels of flame retardancy without the formation of smoke or corrosive and potentially toxic fumes. The use of fillers as flame retardants has recently been reviewed by Rothon [23]. Essentially the key features are an endothermic decomposition to reduce the temperature, the release of an inert gas to dilute the combustion gases and the formation of an oxide layer to insulate the polymer and to trap and oxidise soot precursors. 

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