Reduction of Manganese

The dissolution of carbon in molten iron in the lower part of the furnace, leads to the reduction of manganese oxide (eq. 15) and some sihea (eq. 14), both in the slag, whereby the subsequent dissolution of these metals occurs in the molten iron. 

Myers CR, KH Nealson (1990) Respiration-linked proton translocation coupled to anaerobic reduction of manganese(IV) and iron (III) in Shewanella putrefaciens. J Bacteriol 172 6232-6238. 

Nealson KH, CR Myers (1992) Microbial reduction of manganese and iron new approaches to carbon cycling. Appl Environ Microbiol 58 439-443. 

Another example for reactions with the insertion of protons is the cathodic reduction of manganese dioxide, which occnrs dnring discharge of the positive electrodes in zinc-manganese dioxide batteries. This reaction can be formulated as... 

The reduction of manganese oxides by aluminum has been used for the production of manganese metal. The process is also a classic example to illustrate thermal energy management in a typical aluminothermic reduction process. 

Manganese (IV) oxide is known to be obtained by means of red-ox reactions. Several methods of precipitation of Mn02 are mentioned in the literature sources either reduction of manganese (VII) (permanganate) or manganese (VI) compounds, for example, by means of hydrochloric acid or hydrogen peroxide,... 

Further reduction of manganese ions and the generation of oxygen vacancies could take place only after all metal vacancies are consumed under cathodic polarization. However, the oxygen vacancy formation and the removal of cation vacancies may not be the only explanation for the hysteresis behavior as shown recently by Wang and Jiang [35],... 

Alternatively, the compound can be prepared by reduction of manganese(ll) iodide with a Grignard reagent in the presence of carbon monoxide under pressure. 

Simple one-electron reduction of manganese tetraoxo anions in aqueous solution is observed only under very alkaline conditions. Hydroxide ion concentrations greater than 0.4 and 10 M are required... 

One-electron reduction by hydrogen abstraction from the solvent leads to 82, which decomposes to diol monoanion 83. The latter is oxidatively cleaved to carbonyl compounds with the concomitant reduction of manganese. 

The positive potential implies that the reduction of manganese is spontaneous. To construct the corresponding cell reaction, we reverse the second half-reaction, obtaining... 

The reduction of manganese in this reaction from the +7 oxidation state in MnC>4-to the +2 oxidation state in the manganese(II) ion, Mn2+, is accompanied by a beautiful color change (Figure 14.8). 

The alkaline dry cell is a modified version of the Leclanche cell in which the acidic NH4C1 electrolyte of the Leclanche cell is replaced by a basic electrolyte, either NaOH or KOH. As in the Leclanche cell, the electrode reactions involve oxidation of zinc and reduction of manganese dioxide, but the oxidation product is zinc oxide, as is appropriate to the basic conditions ... 

Spinel notation [93]. It is characterised by a pressed lattice (a=0.816 nm instead of 0.824 nm for LiMn204) and has all manganese ions in 4+ oxidation state. The composition of mechanochemically prepared spinels, probably, can be described by a similar formula (Li,D )-[(Mn""Mn l2.,D,]04 or LiMn204+z- On the increase of calcination temperature, the process of reduction of manganese ions and annealing of defects occur. 

Mechanism The mechanism of the aliphatic side-chain oxidation as shown in Scheme 7.34 probably involves manganese-oxygen-carbon bonding with subsequent reduction of manganese and oxidation of carbon to yield aldehyde, which is much more vulnerable to oxidation with permanganate. 

When the mixture is heated a further reaction takes place, with reduction of manganese to the bipositive state ... 

Myers C. R. and Nealson K. H. (1988) Microbial reduction of manganese oxides interactions with iron and sulfur. Geochim. Cosmochim. Acta 52, 2727-2732. 

Bromfield, S.M. and David, D.J., 1976. Sorption and oxidation of manganous ions and reduction of manganese oxide by cell suspensions of a manganese oxidising bacterium. Soil Biol. Biochem., 8 37—43. 

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