The method of producing iron oxide (iii) for ferrites

 

(57) Abstract:

The method of producing iron oxide (III) to iron from spent etching solutions, which consists in adding to the solution polydimethyldiallylammonium in the amount of 1 - 2 wt.% in terms of SiO2contained in the solution, filtering the resulting precipitate, and the solution supply to oxidative thermal decomposition.

The invention relates to metallurgy, in particular to methods of producing iron oxide (III) for ferrites with low content of impurities from spent hydrochloric acid pickling solutions of the rolling mills.

Used for the production of ferrites iron oxide (III) should be inexpensive and have a low content of impurities such as silicon, magnesium, copper, Nickel, chromium and others.

A method of obtaining inexpensive iron oxide (III) from hydrochloric acid waste pickling solutions (FTS) rolling production by feeding the solution into the furnace, thermal decomposition when blowing furnace gas with oxygen, where thermal decomposition of the chlorides of iron, forming iron oxide (III) [1].

However, the thus obtained iron oxide (III) has increased steriade runoff from use as a flocculant of polydimethyldiallylammonium [2] . However, in this case used flocculant type. In addition, in the work not specified on the cleaning solutions of the above-mentioned non-ferrous and ferrous metals.

The closest technical solution is the method of producing iron oxide (III) with a small content of impurities (silicon) [3], which consists in the fact that the OTP type high-molecular flocculant, which is used as polyacrylamide in the amount of 4% relative to the weight of silicon compounds contained in the solution (in terms of SiO2). The solution was incubated for 20 min for coagulation. Dioxide is filtered off and the solution serves on thermal decomposition where to get iron oxide (III). The disadvantage of this method is that according to this method ensures only clean from compounds of silicon and does not provide magnesium, copper, Nickel, chromium and other impurities.

The aim of the invention is to increase the purity of the obtained iron oxide (III).

This objective is achieved in that in the method of producing iron oxide (III) from hydrochloric OTP rolling operations, including the addition of high-molecular flocculant, exposure and filtration of the solution followed by immediatamente in the amount of 1 - 2 wt.% in terms of SiO2contained in the solution. Due to the introduction of the compounds into solution in the specified quantity in the etching solution is formed by a silica gel, which is equivalent to arise in the solution of the adsorbent, which enables effective cleaning from the following impurities: magnesium, copper, chromium, Nickel and others. In the next step, the silica gel is separated from the solution by filtration through Samaraenergo column with Mylar download. The purified solution serves to oxidative thermal decomposition where to get pure iron oxide (III). Better cleaning solution from silicon compared using as the collector of impurities polydimethyldiallylammonium according to the proposed method due to the fact that polydimethyldiallylammonium translates nesfokusirovanno silicon compounds volatile chetyrehhloristy silicon, which is removed when termorasshirennyi.

Polydimethyldiallylammonium get the reaction taking place at room temperature between dimethylamine and allyl fluoride, followed by polymerization of the monomer at 75-110oC in the presence of peroxodisulfate ammonium.

diallylammonium in the amount of 1 - 2 wt.% in terms of SiO2contained in the solution. It is this concentration specified flocculant leads to the production of iron oxide (III) with low content of impurities (silicon, Nickel, chromium, magnesium, copper, and others). These differences allow to draw a conclusion on the conformity of the proposed technical solution the criterion of "novelty". The features distinguishing the claimed technical solution to the prototype, not identified in other technical solutions and, therefore, provide the inventive solution according to the criterion of "significant differences".

The inventive method can be implemented as follows:

Example. To 5 liters of waste hydrochloric acid pickling solution containing the chlorides of iron (250-300 g/l), the silicon compound (0.5 g/l) and other impurities (Nickel, chromium, magnesium, copper), added polydimethyldiallylammonium, left the solution in contact with the polyelectrolyte for 20 min, then the solution was filtered on a column with Mylar loading and subjected to thermohydraulic, during which he received the iron oxide (III). In parallel experiments received iron oxide (III) according to the method and analog prototype. Tests for impurities was performed according to standard techniques. The results are shown in the generate OTP (see Settings oxides and carbonates of manganese for iron". The Handbook, edited by Golubkov L. A. , 1987).

When the outlet concentration outside of the claimed invention (see table) at the bottom there is a noticeable decrease in the degree of purification of Fe2O3the upper output of the scope of the invention or does not increase the degree of purification or even reduces it.

The analysis of the data shown in the table, it is seen that the inventive method is much more efficient compared to the prototype. Indeed, the degree of purification of silicon, copper, Nickel, chromium and magnesium when using the proposed solutions increases by about 1.5 times.

The method of producing iron oxide (III) to iron from spent pickling solution of rolling operations, including cleaning, initial solution by the introduction of the flocculant, separating the resulting precipitate and oxidative heat treatment of the filtrate, characterized in that as a flocculant injected polydimethyldiallylammonium in the amount of 1 - 2 wt.% in terms of SiO2containing in solution.

 

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The invention relates to the production of metal oxides and, in particular, iron oxide (III), used as the primary source component in the manufacture of ferrites

The invention relates to inorganic chemistry, and in particular to methods for producing metal oxide, and can be used to obtain pigments, catalysts, semiconductor materials

FIELD: metallurgy; building industry; varnish and paint industry.

SUBSTANCE: the invention is pertaining to the field of metallurgy, building industry, varnish and paint industry, in particular, to the method of production of a red ferrioxide pigment. A ball mill is charged with industrial water, loaded with iron oxide with concentration of 500-900 g/dm3, poured with a neutralizing agent in the amount ensuring pH 6 ÷ 10. The iron oxide is formed at a thermal decomposition of the hydrochloride solutions used at etching treatment of carbon steels. As a neutralizing agent it is possible to use caustic soda, a slaked lime, microcalcite. The suspension is pulped for 3-5 hours, put in a reactor with a stirrer, where it is washed out with formation of a suspension, filtered off and dried. The target product has the following parameters: pH 5 ÷ 8; the share of water-soluble salts - 0.02-0.03 %; dispersing ability - 27-30 microns; hiding power - 6 ÷7 g/m2. The invention allows to simplify process and to upgrade parameters of the pigment.

EFFECT: the invention allows to simplify process and to upgrade parameters of the pigment.

2 cl, 1 tbl, 1 ex

FIELD: pigment technologies.

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EFFECT: lowered FeOOH suspension hydrothermal heat treatment temperature and increased pigment preparation productivity.

1 tbl, 12 ex

FIELD: chemical industry; metallurgy industry; other industries; methods of production of the high purity ferric oxides.

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EFFECT: the invention ensures the increased purity of the produced ferric oxides and productivity at their production.

9 cl, 12 ex

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EFFECT: production of phosphate adsorbent with lowered chlorine content of for oral and parenteral preparations for human or animals.

23 cl, 5 ex

FIELD: chemistry.

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EFFECT: possibility to prepare highly dispersed lamellar particles of natural iron oxide.

15 cl

FIELD: chemistry.

SUBSTANCE: method for preparation of iron oxide pigment from specularite includes specularite milling up to particle size more than 1 mm - 5 mm, after material concentration with magnetic separation up to content of α-Fe2O3 more than 60.0 wt % specularite is concentrated again. Concentrated specularite can serve as starting material for obtaining of pigment with dull luster consisting of iron mica with Fe2O3 content more than 85 wt % which includes thin scaly plates in amount more than 50 wt % and is featured with residue after wet sieving on a sieve with mesh size 63 mcm not more than 35 wt %.

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8 cl, 2 tbl, 5 ex

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EFFECT: high degree of utilisation of raw material, high output and whiteness of the product, as well as simplification of the process and reduction of amount of wastes.

17 cl, 4 dwg

FIELD: chemistry.

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22 cl, 1 dwg

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9 cl, 3 tbl, 3 ex

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2 dwg, 5 ex

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