Method of producing magnetoactive compound

FIELD: chemistry.

SUBSTANCE: to obtain a magnetoactive compound, ligosulphonates first undergo nitrosation with sodium nitrite in an acidic medium and the magnetoactive compound is then deposited in the presence thereof. During nitrosation, the acidic medium is formed by adding an acid, preferably nitric acid.

EFFECT: invention increases magnetic susceptibility of the magnetoactive compound.

2 cl, 1 tbl, 19 ex

 

The invention relates to the production of magnetic compounds - basics magnetic fluids, which have a unique combination of yield strength and ability to interact with the magnetic field. Their properties are determined by a set of characteristics, the components (hard magnetic phase, dispersion medium and stabilizer), varying which can widely change the physico-chemical parameters of magnetic fluid depending on the conditions of their application. Efficiency of application of the magnetic fluid is determined by the saturation magnetization and resistance to the action of gravitational forces and magnetic fields. Magnetic fluids for use in high-speed seals and bearing assemblies must have a low viscosity and evaporation in combination with a high thermal stability when used as a magnetic ink on the contrary, high evaporation. Magnetic fluids intended for use in biology and medicine, should be non-toxic and stable when in contact with living cells and tissues of the body.

Mechanical dispersion method for the production of fine magnetic materials is the most effective for producing the magnetic fluid. The first magnetic fluid were obtained Spatalos [Papell S.S. Low viskosity magnetic luid obtaned by the colloidal suspension of magnetic particles. Patent USA No. 3215572, USA Cl. 149-2. 1965] by wet mechanical grinding particles of magnetite in ball mills for 1000 hours

Rkaiser improved the described process and received magnetic liquid water, organic compounds (including aromatic hydrocarbons and ethers [R. Kaiser, G. Miskolczy//J. Appl. Phys., 1970, V.41, №3, P.1064-1072. Kaiser R. Ferrofluid composition. Patent USA No. 3700595, Int. Cl. H01F 1/10, 1972].

The main disadvantages of the method of the dispersion was low productivity, as well as contamination of the magnetic fluid product abrasion of the balls in the mill. In addition, the resulting disperse phase was characterized by a considerable range of particle sizes.

Also known is a method of obtaining magnetic compounds from natural mineral siderite [General and inorganic chemistry. Mccareins. Seadragon. - S]. The disadvantages of this method are the low productivity and high temperatures.

The magnetic particles of the compounds of colloidal dimensions can be formed through condensation of individual molecules. The size of the resulting particles is significantly influenced by the conditions under which there is a Union of individual molecules in the particles, therefore, to obtain colloidal particles of magnetic materials use different variants of the method.

One of the variants of the method of condensation is what I reaction chemical condensation of fine magnetite [Elmore W..// Phys. Rew., 1938, V.54, R]:

2 Fl3+FeCl2+8 NaOH →FeO4↓+8 NaCl+4 H2O.

10%solutions of FeCl2·H2O and FeCl3·6H2O mixed at 70°C and with constant stirring to add an excess of 10%NaOH solution. To limit the growth of particles was used intensive mixing of the solutions. To obtain magnetite desired composition ratio of salts of Fe3+/Fe2+should be 2 to 1.

There are ways of obtaining magnetic fluids and contrast media based on organic compounds. As the magnetic component used magnetite precipitated from a mixture of salts of iron (II) and iron (III) 25%solution of ammonium hydroxide (U.S. Pat. The USSR№№568598, 861321, 966015, 978860).

Replacement of sodium hydroxide to ammonium hydroxide allows the coprecipitation of salts at 25...40°C.

Magnetite magnetic fluid water-based was proposed by Neal [Neal J.A. Clarification process. Patent USA 4088779, SW 1/20, 1978; Neal J.A. Clarification process. Patent USA 4110208, SW 1/20, 1978]. To stabilize the magnetite particles with an average size of about 10 nm, obtained by a chemical condensation, used by-product of bisulfite treatment of wood - sodium lignosulphonate. The disadvantage of the Nile is the necessity of using two iron salts and prolonged exposure at elevated temperatures. The product obtained p and low temperatures, is not magnetized.

Closest to the proposed method is a method, in accordance with which it is originally from a solution of salt of iron (II) is precipitated carbonate of iron (II), which is at a temperature of 55...60°C for 1 h becomes magnetized magnetite separated from the liquid by decantation to pH 7 [U.S. Pat. Of the Russian Federation No. 2230705, IPC7C01G 49/08. The method of obtaining magnetic connection // Belikov VG, Coregen A.G., Sajeev SO, Zulfikarov I.N. Application 2000109795/02, 19.04.2000. Published 20.06.2004].

The disadvantage of this method is low relative magnetic susceptibility of the resulting magnetic connection.

The magnitude of the magnetic susceptibility magnetic compounds largely depends on the efficiency of various devices: sealing, damping, apparatus for purification of water from petroleum products.

Transport capacity magnetoactive materials for biology and medicine is also largely determined by magnetic susceptibility.

The task of the invention to provide a magnetic connection with high relative magnetic susceptibility.

This is achieved by the fact that magnetic connection is formed by deposition from a solution of salt of iron (II), which is nitrosated in the presence of lignosulphonic to the slot.

The proposed method is as follows. Sodium salt of iron (II) is added to the estimated number nitrosated lignosulphonic acid and the resulting solution podslushivaet. Eye-catching turquoise precipitate quickly compacted and after some time turns into a magnetic connection with high relative magnetic susceptibility.

Example 1. For the deposition of magnetic compounds were mixed with 10 ml of a solution of the original lignosulfonate concentration of 7.4 mg/ml; 0.8 ml of a solution of sulphate of iron (II) concentration of 27.8 mg/ml, and 2 ml of NaOH solution concentration of 40 g/L. the Mass flow rate of iron in relation to the original lignosulfonate was 60%. Immediately stood out sediment, turquoise. The relative magnetic susceptibility, measured after 20 min after mixing of the reagents, was 0 g/g of iron.

Example 2. The deposition of the magnetic compound was carried out under the conditions of example 1, wherein measuring the relative magnetic susceptibility conducted after 240 min after mixing of the reagents.

The relative magnetic susceptibility was 0.1 g/g of iron.

Example 3. The deposition of the magnetic compound was carried out under the conditions of example 1, characterized in that the reaction mixture was kept in an incubator for 5 min at a temperature of 80°C. relative to the positive magnetic susceptibility, measured 15 min after cooling the reaction mixture, was 1.1 g/g of iron.

Example 4. The deposition of the magnetic compound was carried out under the conditions of example 3, characterized in that the measurement of the relative magnetic susceptibility was performed at 240 min after mixing of the reagents. The relative magnetic susceptibility, measured after 240 min after cooling, the reaction mixture was 4.4 g/g of iron.

Example 5. For the deposition of magnetic compounds were mixed with 10 ml of a solution nitrosated lignosulfonate concentration of 0.74 mg/ml, 0.8 ml of a solution of sulphate of iron (II) concentration of 27.8 mg/ml, and 2 ml of NaOH solution concentration of 40 g/L. Nitrosation of lignosulfonate was carried out as follows. In a volumetric flask with a capacity of 200 ml was made 80 ml of a solution of the original lignosulfonate concentration of 1.86 g/l, 8 ml of a solution of sodium nitrite concentration of 2 g/l (consumption of sodium nitrite in relation to the lignosulfonate was 10.8%) and 8 ml of acetic acid concentration of 10%, the volume of solution was brought to the mark with distilled water. The nitrosation reaction was carried out for 60 minutes

The consumption of iron in relation to the original lignosulfonate was 60%. Immediately stood out sediment, turquoise. When storing sediment was compacted, the color changed to dark brown, he had acquired the properties of the magician is itnow fluid. The relative magnetic susceptibility, measured after 120 min after mixing of the reagents, was 1.0 g/g of iron.

Example 6. The deposition of the magnetic compound was carried out under the conditions of example 5, characterized in that the measurement of the relative magnetic susceptibility was performed at 1200 min after mixing of the reagents. When storing the resulting turquoise sediment was compacted, the color changed to dark brown, he had acquired the properties of magnetic fluid. The relative magnetic susceptibility of 1.8 g/g of iron.

Example 7. The deposition of the magnetic compound was carried out under the conditions of example 5, characterized in that instead of 0.8 ml was added 1.2 ml of a solution of sulphate of iron (II). The consumption of iron in relation to the original lignosulfonate was 90%.

When storing the resulting turquoise sediment was compacted, the color changed to dark brown, he had acquired the properties of magnetic fluid. The relative magnetic susceptibility, measured after 120 min after mixing of the reagents, was 9.6 g/g of iron.

Example 8. The deposition of the magnetic compound was carried out under the conditions of example 7, characterized in that the measurement of the relative magnetic susceptibility was performed at 1200 min after mixing of the reagents. When storing the resulting turquoise sediment was compacted, the color changed to dark brown, unparallel properties of magnetic fluid. The relative magnetic susceptibility was 17.4 g/g of iron.

Example 9. For the deposition of magnetic compounds were mixed with 10 ml of a solution nitrosated lignosulfonate concentration of 0.74 mg/ml, 0.8 ml of a solution of sulphate of iron (II) concentration of 27.8 mg/ml, and 2 ml of NaOH solution concentration of 40 g/L. Nitrosation of lignosulfonates produced as follows. In a volumetric flask with a capacity of 200 ml was made 80 ml of a solution of the original lignosulfonate concentration of 1.86 g/l, 8 ml of a solution of sodium nitrite concentration of 2 g/l (consumption of sodium nitrite in relation to the lignosulfonate was 10.8%) and 8 ml of nitric acid concentration of 10%, the volume of solution was brought to the mark with distilled water. The nitrosation reaction was carried out for 60 minutes

The consumption of iron in relation to the original lignosulfonate was 60%. Immediately stood out sediment, turquoise. When storing sediment was compacted, has changed its color to dark brown, he had acquired the properties of magnetic fluid. The relative magnetic susceptibility, measured after 120 min after mixing of the reagents, 0.5 g/g of iron.

Example 10. The deposition of the magnetic compound was carried out under the conditions of example 9, characterized in that the measurement of the relative magnetic susceptibility was performed at 1200 min after mixing of the reagents. When the storage is Sri formed turquoise sediment was compacted, the color changed to dark brown, he had acquired the properties of magnetic fluid. The relative magnetic susceptibility was 1.3 g/g of iron.

Example 11. The deposition of the magnetic compound was carried out under the conditions of example 9, characterized in that instead of 0.8 ml was added 1.5 ml of a solution of sulphate of iron (II). The consumption of iron in relation to the original lignosulfonate amounted to 112%. When storing the resulting turquoise sediment was compacted, the color changed to dark brown, he had acquired the properties of magnetic fluid. The relative magnetic susceptibility, measured after 120 min after mixing of the reagents, 13.2 g/g of iron.

Example 12. The deposition of the magnetic compound was carried out under the conditions of example 11, characterized in that the measurement of the relative magnetic susceptibility was performed at 1200 min after mixing of the reagents. When storing the resulting turquoise sediment was compacted, the color changed to dark brown, he had acquired the properties of the liquid. The relative magnetic susceptibility was 19.5 g/g of iron.

Example 13. The deposition of the magnetic compound was carried out under the conditions of example 9, characterized in that instead of 0.8 ml was added 2 ml of a solution of sulphate of iron (II). The consumption of iron in relation to the original lignosulfonate was 150%. When storing the resulting turquoise sediment was compacted,the color changed to dark brown, he bought properties of magnetic fluid. The relative magnetic susceptibility, measured after 120 min after mixing of the reagents, 4.8 g/g of iron.

Example 14. The deposition of the magnetic compound was carried out under the conditions of example 13, characterized in that the measurement of the relative magnetic susceptibility was performed at 1200 min after mixing of the reagents. When storing the resulting turquoise sediment was compacted, the color changed to dark brown, he had acquired the properties of the liquid. The relative magnetic susceptibility made 32.6 g/g of iron.

Example 15. For the deposition of magnetic compounds were mixed with 10 ml of a solution nitrosated lignosulfonate concentration of 0.74 mg/ml, 2.5 ml of a solution of sulphate of iron (II) concentration of 27.8 mg/ml, and 2 ml of NaOH solution concentration of 40 g/L. Nitrosation of lignosulfonates produced as follows. In a volumetric flask with a capacity of 200 ml was made 80 ml of a solution of the original lignosulfonate concentration of 1.86 g/l, 8 ml of a solution of sodium nitrite concentration of 3 g/l (consumption of sodium nitrite in relation to the lignosulfonate was 16.1%) and 8 ml of nitric acid concentration of 10%, the volume of solution was brought to the mark with distilled water. The nitrosation reaction was carried out for 60 minutes

The consumption of iron in relation to the original lignosulfonates were 188%. Immediatly stood out sediment, painted in turquoise color. When storing sediment was compacted, has changed its color to dark brown, he had acquired the properties of magnetic fluid. The relative magnetic susceptibility, measured after 120 min after mixing of the reagents, was 4.9 g/g of iron.

Example 16. The deposition of the magnetic compound was carried out under the conditions of example 15, characterized in that the measurement of the relative magnetic susceptibility was performed at 1200 min after mixing of the reagents. When storing the resulting turquoise sediment was compacted, the color changed to dark brown, he had acquired the properties of magnetic fluid. The relative magnetic susceptibility amounted to 32.7 g/g of iron.

Example 17. The deposition of the magnetic compound was carried out under the conditions of example 15, wherein prior to measuring the relative magnetic susceptibility was performed heat treatment at 100°C for 3 minutes. The resulting turquoise sediment was compacted, the color changed to dark brown, he had acquired the properties of magnetic fluid. The relative magnetic susceptibility, measured after 3 min after heat treatment was 9.6 g/g of iron.

Example 18. The deposition of the magnetic connection of the prototype was carried out as follows: 2 g of sodium carbonate was dissolved in 25 ml of water, filtered (solution A). 2 g of iron sulfate (II) rest rely in 25 ml of water (solution B). To the solution B was added to the solution And, thus separated precipitate turquoise. Sediment 1 h and kept at 60°C, the precipitate acquired a dark brown color. To measure the relative magnetic susceptibility were collected 2 ml of thoroughly mixed suspension containing 16 mg of iron. The relative magnetic susceptibility was 1.3 g/g of iron.

Example 19. The deposition of the magnetic compound was carried out under the conditions of example 18, characterized in that the measurement of the relative magnetic susceptibility was performed at 120 min after the heat treatment. The relative magnetic susceptibility was 6.5 g/g of iron.

The results obtained during the synthesis of magnetic compounds are summarized in the table, from the data which shows that the proposed solution allows to obtain a magnetic connection, with a significantly higher relative magnetic susceptibility and magnetic properties of the liquid.

1. The method of obtaining magnetic compounds by precipitation from a solution of salt of iron(II), characterized in that the first conduct the nitrosation of lignosulfonate with sodium nitrite in an acidic medium, and then precipitated magnetic connection in their presence.

2. The method according to claim 1, characterized in that an acidic environment in the implementation of nitrosation with whom represent the addition of acid, mostly nitrogen.



 

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2 cl, 1 ex

FIELD: paint-and-varnish industry; construction engineering; painting plastics and leather; production of enamel paints, primers, putties, wall-paper and veneer.

SUBSTANCE: solution of hydraulic washing-out of used melt of titanium chlorates containing ferrous chloride (II) is treated with alkaline reagent to pH= 2.5-4.5 at precipitation of oxyhydrates of metals. Solution is separated from sediment by filtration. Cleaned solution thus obtained is mixed with solution obtained after leaching-out of copper-containing melt of process of cleaning titanium tetrachloride from vanadium compounds by means of copper powder. Ratio of volumes of said solutions is 1 : (0.5-2), respectively. Mixed solution is treated with alkaline reagent to pH= 9-11. Suspension thus obtained is subjected to filtering. Sediment is washed, dried and calcined additionally at temperature of 400-700°C. Proposed method makes it possible to utilize wastes of process of production of titanium dioxide from titanium tetrachloride. Pigment thus obtained has rich black color, reflection coefficient of 3.5±0.5%, hiding power of 4.5±0.5 g/m2 and pH of aqueous suspension of 7.0±0.5.

EFFECT: enhanced efficiency.

2 cl, 1 ex

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