Iron sulfate, basic

Table 5.1.1 Typical Conditions for the Formation of Monodispersed Basic Iron Sulfate Particles...

Fig. 5.1.3 TEM images (a) basic iron sulfate particles prepared by aging a 0.088 mol din-3 Fe2(S04)3 at 98°C in an oven for 3 h (b) carbon replica of the same particles as described in (a) (c) basic iron sulfate particles prepared by aging a solution of 0.18 mol dm-3 in Fe(N03)3 and 0.53 mol dm-3 in Na2S04 in oil bath heated from room temperature to 80°C at a constant rate of 1.5°C min-1 and aged at 80pC for 1.5 h (d) carbon replica of the same panicles as in (c), but aged for 2 h at 80°C. (From Ref. 9.)...

Figure 9. No significant formation of sulfur or oxidized sulfur was observed. In contrast to this, aging in air leads to formation of basic iron sulfate, preserving the ratio of sulfur-to-iron atoms in the bulk. Aging in distilled water did not result. in any modification of the pyrite surface. The effect of collectors and depressors was more difficult to see, however. It was not possible to discern appreciable changes in the C or S peaks after adsorption of the collector. Similarly, C and N could not be detected when NaCN adsorbs on the surface. Adsorption of...

The results of the fitting procedure (table i) reveal chat the divalent iron phase is Szomolnokite (FeS04 H20). The trivalent iron phase is probably a hydroxylated basic iron sulfate like Butlerite (FeSC>40H 2H20) [8]. The data also reveal that the catalysts after operation contain well crystallized Szomolnokite, as follows from the observed small line width of its spectral contribution. The presence of die sextuplet in the spectrum of the used catalyst B shows that still some iron(III) oxide is present as also found by XRD. 

A number of products are being marketed under the trade name POLYON. These include coated basic fertilizer materials, ie, urea, potassium nitrate, potassium sulfate, potassium chloride, ammonium sulfate, ammonium phosphate, and iron sulfate, in various particle sizes. Coatings weights on urea vary from 1.5 to 15%, depending on the release duration desired. Table 6 Hsts typical products. 

In the jarosite process, the precipitation of iron occurs from acidic sulfate solutions as one of a group of basic ferric sulfates known as jarosites. The conditions for the precipitation of iron in the specific form of jarosite require a solution pH of about 1.5 and a temperature of about 95 °C. The reaction may simplifiedly be represented as ... 

The compound is oxidized by moist air forming basic iron(III) sulfate. Aqueous solutions exposed to air also undergo oxidation the reaction, however, is very slow. The rate of oxidation increases with temperature and the pH. In alkaline medium, the oxidation is much faster. In solution, it also is oxidized to Fe + by radiations from radioactive substances. This reaction is utilized to measure the radiation dose in dosimeter solutions. 

One of the earliest references to a reaction in solution, which, as we now realize, depends upon the formation of a coordination compound, was recorded by Pliny who stated that the adulteration of copper sulfate by iron sulfate could be detected by testing with a strip of papyrus soaked in gall-nuts, when a black colour developed if iron were present. A. Libavius (1540-1616) noted how ammmonia present in water could be detected by the blue colour formed with a copper salt and A. Jacquelain (1846) actually determined copper salts in terms of the blue colour formed on adding ammonia. Later developments used coordination compounds formed from ethylenediamine and other polyamines.3 T. J. Herapath determined iron(III) as its red isothiocyanate complex in 1852 and the basic procedure is used today.3... 

Sulfates. Iron(II) sulfate heptahydrate [7782-63-0], FeS04TH O, forms blue-green monoclinic crystals that are very soluble in water and somewhat soluble in alcohols. It is known by many other names including cupperas, green vitriol, and iron vitriol. The compound is efflorescent in dry air. In moist air, the compound oxidizes to yellow-brown basic iron(III) sulfate. Aqueous solutions tend to oxidize. The rate of oxidation increases with an increase in pH, temperature, and light. The compound loses three waters of hydration to form iron(II) sulfate tetrahydrate [20908-72-0], FeS04 TH O, at... 

Other investigators (14, T3) contend that the bacteria biologically oxidize the ferrous to the ferric state as sulfate, which in turn attacks the metal sulfides ores, resulting in both the dissolution of the metal and the oxidation of the sulfide. In the process the ferric iron reduces back to the ferrous state. An increase in the pH causes the basic ferric sulfate to precipitate (self-buffering action) with corresponding release of sulfuric acid. This has the cumulative effect of increasing the acidity of the mine water. 

The nickel in solution in the slurry is completely precipitated without liquids-solids separation with metallic powered iron at about 150°C under a pressure of 150 psig. The precipitated nickel contains occluded basic ferric sulfates which are decomposed by calcining at 950°C to produce a mixture of metallic nickel, metallic iron, and iron oxides. Melting of this mixture with a slag is calculated to yield a ferro-nickel containing more than 55% nickel. 

Assumptions about the basic method of disposal of the coal-cleaning waste must be made. For this paper, we assumed that the valley-fill method would be used. In this method, a narrow downward-sloping valley near the cleaning plant is filled, in benches, from the upper end. As the upper benches reach contour level, the pile is covered with sufficient soil to retard water percolation to one-third that of an uncovered pile. The drainage from such a waste pile has the characteristics of acid mine drainage, with most of the dissolved solids being iron sulfates. 

Wet chemical qualttative analysis Catalyst samples analyzed directly after the reactor experiment only showed the presence of ferrous ions. The catalysts samples after exposure for a week to air revealed also the presence of ferric ions. This indicates that the iron sulfate fomied in the reactor is indeed an iron(II) sulfate, which can easily be convened into basic irofi(III) sulfate salts in wet air. 

Matijevic, E., Sapieszko, R.S.. and Melville. J.B., Ferric hydrous oxide sols. 1. Monodispersed basic iron(III) sulfate particles. J. Colloid Interf. Sci.. 50, 567, 1975. 

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