The method of obtaining micaceous iron pigments
(57) Abstract:The invention is intended for the chemical and paint industries and can be used to obtain enamels and paints. A solution of FeCl2with a concentration of 100 g/DM3treated with NaOH solution with a concentration of 80 g/DM3and oxygen in the presence of inert media dump clay slimes potash production. The ratio of sludge:iron in the target product 1: (0,20,8). The temperature of the suspension (805)oWith, the synthesis time is 45-50 hours the Precipitate is filtered off, washed and dried. Get shell micaceous iron pigments yellow color with opacity 20 g/m2. The filtrate under layer hypochlorite slurry containing 40-80 g/DM3Ca(OCl)2and 10-30 g/DM3CaO. The filtrate is chosen so that the pH of the slurry 9. The pulp is treated with 0.2% solution of polyacrylamide. The precipitate is filtered off, washed with a working solution, water, dried at (1005)oWith, pulverized, calcined at (5505)oC. Get micaceous iron pigment corresponding to the requirements pigments "red iron oxide". The degree of extraction of iron from the filtrate of 99.9%. The invention allows to dispose of the sludge potash production, PA. 2 C.p. f-crystals. The invention relates to the field of inorganic chemistry and can be used in technology of inorganic substances to obtain shell micaceous iron pigments of different colors and purposes.Known (B. F. White, I. C. Riskin. Chemistry and technology of pigments. L.: Chemistry, 1974, S. 372-379) the method of obtaining micaceous iron pigments, consisting in the air oxidation of the solution of salt of iron (II) in the presence of a pre-prepared "germ", taken in an amount of 10-15% by weight calculated on the resulting pigment.As a solution of salt of iron (II) typically use FeSO47H20, sedimentation are ammonia at pH 3.5 to 4.0; the initial concentration of ferric sulfate 100-120 g/DM3residual 20-30 g/DM3. The pigment concentration of sediment in suspension 50-60 g/DM3. At the end of the synthesis process, the suspension is filtered, the pigment on the filter is washed-washed from the mother liquor, dried and washed, if necessary dispersed. Depending on the temperature of drying and/or calcination get micaceous iron pigments from yellow to red.For reasons that impede the achievement of specified following technical result when using ignoti process, due to the high quality requirements previously received "germ";
high residual concentration of iron (II) in solution, which requires special measures for the disposal of the mother solutions: 20-30 g/DM3FeSO4and 70-80 g/DM3(NH4)2SO4.The closest way to the same destination to the claimed invention by a combination of traits is known a method of obtaining a shell micaceous iron pigments on kaolin (Y. P., Kiev // non-ferrous metallurgy, 1995, 6, S. 34-39) prototype.The way the prototype is the oxidation of iron chloride (II) by oxygen at pH of 2.5-4.0 and T = 805oWith over 40-50 hours in the presence of inert carrier is kaolin. As a result of synthesis are the so-called shell micaceous iron pigments. After synthesis, the suspension is filtered, the pigment is washed with water and dried at 205oC. In the method according to the prototype instead of the "germ" is used an inert carrier, which is used as kaolin derived from the mineral kaolinite, white substance, the particles of which 1-5 microns.Factor hindering the achievement of specified following technical result is that pigmento is not very high because of the large quantities of coverage and they are of very limited use, for example, for the preparation of enamels and paints for the floor. This can be explained, apparently, the specific surface properties of the kaolin particles and their sizes (1-5 μm). It should be added that the original mineral raw material for production of kaolin is relatively cheap, however, for the preparation of kaolin suitable for use as the inert carrier, require significant material and energy costs associated with classification, sieving, drying, dispersion, etc., These costs, in turn, one way or another affect the cost of the obtained shell micaceous iron pigments.The claimed technical solution aimed at addressing the goals to improve the quality of the shell micaceous iron pigments by improving their pigmentary characteristics and efficiency (profitability) of the process as a whole by expanding the resource base and prevent waste production and iron losses.This technical result in the implementation of the invention is achieved in that in the known method of obtaining micaceous iron pigments, including the processing of the initial solution stature, subsequent filtering the suspension, washing and drying the precipitate, the peculiarity lies in the fact that, as the inert carrier used conveyor clay slurries potash production.In addition, the feature of the method lies in the fact that the waste clay slurry is used in an amount to provide a ratio of sludge : iron in the target product, which is 1:(0.2 to 0.8).In addition, the feature of the method lies in the fact that uterine solutions-the filtrates after synthesis of the pigment served under a layer hypochlorite slurry containing 40-80 g/DM3CA(l)2and 10-30 g/DM3CaO in an amount to provide a final pH value of the pulp 9.In addition, the feature of the method lies in the fact that the mixed slurry is filtered, the precipitate is washed, dried and/or calcined.Under other equal conditions, the proposed method is characterized by new techniques of performing actions (the use of certain substances, materials, reagents, without which it is impossible the implementation of the method, new modes and parameters of the process) and a new order of execution of actions provides the achievement of the technical result in the proposed iget inventive step, so as not necessary for professionals in the obvious way from the prior art.The analysis of the prior art suggests that the implementation of the synthesis micaceous iron pigments on inert carriers are widely known. At the same time as inert carrier (instead of "germs") in the known methods are fine (1-5 μm) solids (inorganic compounds) a white color, in particular kaolin, gypsum, talc, mica (Muscovite), barite, chalk, etc., the Choice of these substances - white color is due to the fact that the color of the medium does not affect the color of the target product is yellow and/or red shell micaceous iron pigments.The proposed technical solution, as the inert carrier used conveyor clay slurries potash production, representing a dirty-dark-brown-brown-moist (90%) sediments that are rich in alkaline salts (KCl, NaCl) and alkaline earth (MgCl2) metals. These sediments themselves have no pigment properties and it is not suitable for direct use in the paint industry even as fillers in the formulation of paints and varnishes. The color of these precipitation (dirty-dark-brown-brown) that is to be placed, there were serious doubts in the ability to change their color, "perfect" its to bright yellow, yellow, orange-red and red. And yet this has been done. Moreover, it appeared that the corresponding color "color standards" and samples of the pigments obtained on the white native - kaolin, pigments obtained in accordance with the proposed method, the synthesized using as inert media dump sludge potash production, their quality is significantly superior to shell micaceous iron pigments on the kaolin.The observed effect until it finds a strictly scientific explanation. One can only assume that the surface of the particles dump sludge potash production has a greater number of defects in the crystal lattice, and therefore in the process of synthesis of this surface is more uniformly covered with a shell of crystals-FeOOH (goethite-yellow pigment) and/or-Fe2ABOUT3(hematite-red pigment).We should also note the following. Used according to the invention as inert carrier conveyor sludge potash production are unusable waste production, directed and generaterule-Promyshlenno region formed several hundred thousand tons of such waste. Numerous (over the last 65 years) attempts to utilize these slurries were unsuccessful. Still not utilized any tons of such waste. In this regard, the final clay slurries potash production are almost limitless source of raw materials as inert carriers for the synthesis of micaceous iron (and possibly other) shell pigment.Analysis of the totality of the features of the claimed invention and achieved this result indicates that between them there is a causal relationship, which is expressed in the fact that the use as inert media dump clay slimes potash production in an amount to provide a mass ratio of the slurry of iron in the target product, which is 1: (0.2 to 0.8), provides quality pigment and production efficiency in General.The presence in the claimed method further operation of the feed stock solution of filtrate after synthesis of the pigment under layer hypochlorite slurry containing 40-80 g/DM3CA(Oh)2and 10-30 g/DM3CaO in an amount to provide a final pH value of the pulp 9, ceteris paribus allows to neutralize mA is here to dispose of doswiadczenie iron in the form of micaceous iron pigments, its properties are similar to properties f mineral pigments ("ochre", "red", and so on).Information supporting the implementation of the invention to provide the above technical result, and comparing the effectiveness of known (the prototype) and the proposed technical solutions described in the examples.Examples of the method.Example 1
For comparison of the effectiveness of the receiving shell micaceous iron pigments were known (prototype) and the present method under strictly identical conditions (time, temperature, concentration, pH and so on), in particular:
the concentration of the original solution of FeCl2-100 g/DM3;
alkaline reagent ("precipitator") -NaOH solution (80 g/DM3);
- pH synthesis: 2,5-3,5;
- the temperature of the suspension in the synthesis process: 805oC;
the time of synthesis: 45-50 h;
a residual concentration of iron (II) in the mother solution (the filtrate) after synthesis of 4-5 g/DM3;
the amount of inert carrier, is introduced into the initial solution of FeCl2before synthesis, was calculated based on the ratio: native: Fl2=1: 0,3.The inert carrier used:
- the th production. The calculation of the number entered in the source solution, was carried out on the washed and dried precipitate.Obtained after synthesis, washing, drying and dispersion samples shell micaceous iron pigments had almost the same yellow color. Comparative tests showed that the hiding power of the pigments obtained by a known method (kaolin) is 30 g/m2; hiding power of the pigments obtained by the proposed method is much higher and amounts to 20 g/m (i.e. consumption of pigment for coloring 1 m substantially 1.5 times below ! ).Example 2
Experiments conducted with the mother solution, the filtrate after synthesis of the pigment (see example 1) containing 4.4 g/DM3iron (II) (degree of reaction or the degree of useful use of iron for the synthesis of shell micaceous iron pigments 90%).For disposal of these solutions of iron (II) and increase the useful life of iron (II) these solutions were processed by the proposed method, in particular mixed with the hypochlorite slurry formed during the purification of exhaust gases from chlorine lime milk and which is highly toxic waste production, which is required about the different modes and parameters of the process. As a result of experiments, it was found that feeding the mother liquor to the surface hypochlorite slurry (or, on the contrary, the supply of slurry to the surface of the solution) leads to intense selection in the gas phase C12and lO2that complicates the technology and requires special measures systems and preventing the formation of explosive mixtures.When submitting the mother liquor under layer hypochlorite slurry containing 10-30 g/DM3CaO, negative phenomena were observed. However, in the case of hypochlorite slurry with low residual concentration of Cao (1-5 g/DM3even when submitting the mother liquor under a layer of the pulp and the final pH value of the mixed pulp 5-7 was also observed intense emission in the gas phase CL2and lO2.When carrying out the process under optimal conditions when the feed stock solution (4.4 g/DM3Fe, 90 g/DM3NaCl, pH 3.0) under a layer hypochlorite slurry containing 10-30 g/DM3CaO and 40-80 g/DM3CA(l)2to a final pH-value of the joint-mixed slurry 9,0 was observed mutual neutralization of waste: the oxidation of Fe(II) to Fe(III) precipitation of oxyhydrates, Fe and westiemed for flocculation of sediment in the amount of 3-5% (by volume) and filtered, the precipitate on the filter was washed for circulating the washing solution and water, washed of salts, dried at 1005oWith, were crushed in a laboratory mortar and progulivali when 55010oC. The resulting products were determined by the basic properties. It was found that the above-mentioned operations, the degree of extraction of iron from solution achieves 99.9 percent. Accordingly exit hardware in commercial product >99.9%.Precipitation, obtained by separation of the iron oxyhydrates of uterine fluids, their properties fully comply with the requirements of micaceous iron mineral pigments of the type "red iron oxide".Thus, the proposed invention provides the achievement of the technical result consists in increasing the quality of the target product and the efficiency of the process as a whole by expanding the resource base and the use of unusable waste and, on the other hand, due to the additional utilization of iron from mother solutions to produce salable products. 1. The method of obtaining micaceous iron pigments, including the processing solution of salt of iron (II) in the presence of inert carrier alkaline reagent and KIS is causesa fact, as the inert carrier used conveyor clay slurries potash production, taken in an amount to provide a mass ratio of the slurry of iron in the target product, equal to 1:(0,2:0,8).2. The method according to p. 1, characterized in that the uterine solutions-the filtrates after synthesis of pigments served under a layer hypochlorite slurry containing 40-80 g/DM2(l)2and 10-30 g/DM3CaO in an amount to provide a final pH value of the pulp 9.3. The method according to PP.1 and 2, characterized in that the mixed slurry is filtered, the precipitate is washed, dried and/or calcined.
FIELD: chemical industry and agriculture; production of hydrosol of ferric iron hydroxide.
SUBSTANCE: the invention is intended for a chemical industry, an agriculture and pedology and may be used at production of solutions for soils reclamation. 0.5 l of a ferric chloride solution with concentration of 0.5 l/mole gram-molecule is poured into a pan. Carbon electrodes are put into the solution. Pass a current of 1А. Each 5-60 seconds polarity of the electrodes is changed. In a result of replacement of anions of the salt for ions of the hydroxyl obtain a stable hydrosol of the ferric iron hydroxide. The invention allows to produce such sols using a simple and a production-friendly method commercially.
EFFECT: the invention allows to produce such sols using a simple and a production-friendly method commercially.