Iron oxalate

Marble Polishing. Oxahc acid is used for marble polishing especially in Italy. It not only removes iron veins by forming water-soluble iron oxalate, but also serves as a polishing auxihary. 

Iron (II) oxide and especially that made by reducing the other oxides, combusts spontaneously if it is heated to 200°C. It also strongly catalyses the combustion of carbon in air. This behaviour can explain the spontaneous inflammable property of the products of burning iron oxalate, which contain this oxide and carbon. When they are placed on the hand and thrown into the air, they form very spectacular showers of sparks. It combusts in contact with liquid oxygen in the presence of carbon. 

Balmer, M.E. Sulzberger, B. Atrazine degradation in irradiated iron/oxalate systems Effect of pH and oxalate. Environ. Sci. Technol. 1999, 33, 2418. 

Deoxygenation of o-nitrobiphenyl (502) to carbazole (1) was realized first by Waterman and Vivian using stoichiometric iron oxalate at 200°C (482,483) (Scheme 5.1). 

Production. Metallic iron pigments are commercially produced by the reduction of acicular (needle-shaped) iron compounds [5.30], As in the production of magnetic iron oxide pigments, the starting materials are iron oxide hydroxides (see Section 3.1.1) or iron oxalates, which are reduced to iron in a stream of hydrogen either directly or via oxidic intermediates. 

Draw the structure of the iron oxalate complex [Fe(C204)3]3-. Describe the coordination geometry, and identify any chelate rings. What are the coordination number and the oxidation number of the iron ... 

Hislop and Bolton (1999) elucidated the complex mechanism of this reduction process. Presumably, it includes a ligand to metal electron transfer in the iron-oxalate complex with formation of an oxalyl radical anion as shown in Eq. 5-13. 

Above 170 °C the amidrazone ylide (36) decomposes with loss of triethylamine and concurrent cyclization to give an 85% yield of 2-phenylbenzimidazole (Scheme 19) (B-75M140800). Poorer yields ( 40%) are obtained when N-benzyl-o-nitroaniline is pyrolyzed in the presence of iron oxalate. No doubt this last reaction is similar in many respects to the reactions shown in Scheme 2. Both 2-phenyl-imidazoles and -benzimidazoles (as well as other 2-substituted analogues) can be obtained as a result of thermal rearrangement of the 1-substituted isomers (Section 4.07.1.2.2), by radical substitution methods (Section 4.07.1.7) or via the 2-lithio derivatives (Sections 4.07.1.6, 4.07.3.7). 

Zhabrova etal. [151] identified the reactions of nickel, cobalt and copper oxalates ( , = 150, 159 and 129 kJ mol respectively) as redox processes in which there is an autocatalytic effect by product metal on the electron transfer step. The decomposition rate was determined by the area of the reactant and results were fitted by the Prout-Tompkins equation. In contrast, the reactions of magnesium, manganese and iron oxalates (f, = 200,167 and 184 kJ mol ) are not autocatalytic and the area... 

Structure on hydrogel properties of 2-hydroxyethyl acrylate determined. " Polymers bearing tertiary amino groups have been synthesised and their fluorescence spectra found to be significantly quenched while maleic anhydride " and cyclododecanones have been found to be effective initiators of the photopolymerisation of styrene. Poly(methylphenylsilane) is also an effective photoinitiator for styrenes and acrylates via a photolytic process to give silyl radicals. Iron oxalate is also an effective photo initiator for acrylate monomers while a theoretical description of the kinetics of free radical dye-initiated polymerisation via an electron transfer process has been proposed. Using the Marcus theory it has been shown that the rate of electron transfer can affect the rate of initiation. 

The four open test tubes are filled to about 1/5 of their height with yellow iron oxalate, l eC204 1.5 1LO and each tube is heated until the latter has been converted to a black residue. Any water vapor which condenses at the top.s of the I ubes is carefully removed with a soft filter paper. The test tubes are then tightly closed with the rubber bungs and put aside for the demonstration. After show-... 

Iron oxalate decomposes on heating to give a pyrophoric mixture of iroii(Il) oxide and metallic iroiij which reacts with oxygen according to the highly exothermic reaction described by the following equation ... 

Mixed ion solutions can be precipitated to produce a solid containing the required ions, although care must be taken to ensure that the correct ratio of ions precipitates. For example, oxalic acid can be used to precipitate zinc iron oxalate from a solution of the ions dissolved in acetic acid ... 

The decomposition of ferrocenyl amines in oxalic acid solution gives iron oxalate 356>. 

Chemicals.— Tannin, perchloride of iron, oxalic acid, ammonia, sulphuric acid. Dissolve in the distilled water in the decanter about as much tannin as will lie on a sixpence. Of the glasses one and three are unprepared numbers two and four contain two drops of perchloride of iron number five about ten drops of a saturated solution of oxaUc acid number six about the same quantity of strong liquid ammonia and number seven a small teaspoonful of sulphuric acid. 

The use of iron oxalate complex is a good way for the preparation of Al-Fe-BEA and Al-Fe-MOR zeolites. The limit of the described procedure is that it is... 

Two typical reactions which are used in chemical actinometry, are the photoreactions of iron oxalate (Parker s solution) [7,121] and of potassium Reinecke s salt [122]. In both cases, photochemistry and analysis are sepa-... 

Ferrites can also be synthesised by the coprecipitation of oxalates. The hydrated iron oxalate, FeC204 2H2O and the oxalates of Mn, Co, Ni or Zn can be coprecipitated from solution by solvent evaporation (Wickham, 1967). The Fe/Me " stoichiometry can be accurately controlled to within 1%. 

Well-ordered macroporous Fc203 can be prepared by using iron oxa-late. " Iron oxalate is soluble in ethanol-water mixed solvents, which can infiltrate the voids of templates. Iron oxalate can be converted to Fc203 without melting to form well-ordered macroporous material. If the oxalate salts are not soluble in alcoholic solution, oxalate or oxalate derivatives can be produced in the voids by a two-step method or an in situ method. In the two-step method, nitrate or acetate salts of Mn, Co or Ni infiltrate the voids and then react with oxalic acid to form oxalate salts in the voids. These oxalate salts can be converted to oxide by calcina-In the in situ method, nitrate of Mn or Fe is dissolved in EG-methanol solution, and the solution infiltrates the voids of templates. By heating the solution, EG is oxidised by nitrate to form metal oxalate derivatives. The metal oxalate derivatives can be converted to metal oxides. 

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