Sorbent for the purification of liquid media
(57) Abstract:Use: as a sorption material for any cleaning liquids, representing himself as a true solution or a food emulsion from radionuclides strontium ions and heavy metals. The inventive sorbent is the product of neutralization of acid extraction waste cereals hydroxide of an alkali metal or ammonium or magnesium, or their carbonates, contains 10,0 - 13,0 wt.% phosphorus has a density of 1.8 - 2.0 g/cm3. 1 Il. The invention relates to applied ecology, specifically to the sorbents on the basis of waste cereals that can help to remove ions of heavy toxic metals and radionuclides are long-lived isotopes from liquid media.Poor environmental conditions, contamination of vast territories ions of heavy metals and long-lived radionuclides, such as strontium and cesium, puts the task of getting from the available raw materials cheap and eco-friendly sorbents for preconcentration and disposal.Known sorbents on the basis of waste vegetable production. These include the sorbents obtained after alkaline or acid leaching waste is-breaking solutions.However, they do not possess selectivity for strontium, though, and are good sorbents for heavy metal ions.The range of the currently proposed sorbents for the purification of liquids from radionuclides is quite broad and includes natural, for example, clinoptilolite and synthetic, for example, NaA and NaX, zeolites, oxyhydrate sorbents on the basis of metal oxides, such as pyrolusite, salts of polyvalent metals and polybasic acids, for example, phosphates of titanium or zirconium spherical granulation or sorbents on the basis of ferrocyanides caused sorption on porous media, both natural and artificial origin (in. A. Milyutin, W. M. of Helis, R. A. Penzin, "Sorption-selective characteristics of inorganic sorbents and ion-exchange resins in relation to the cesium and strontium", radiochemistry, N 3, S. 76-82, 1993).However, the use of the above sorbents in the static mode in the form of a coarse powder or pellets requires long-term, from 48 to 96 h of contact with the purified liquid, which does not allow to use them for cleaning food emulsions of milk, and in addition, considerable effort would be required for sorbent regeneration for them is orania purified product.When using these sorbents in a dynamic mode in which the liquid is passed through the sorption column, and the sorbent used in the form of fine powder, rapidly increasing the hydrodynamic resistance, slowing down the process of filtration, which also leads to an increase in cleaning time, and therefore, there are additional difficulties with the subsequent cleanup sorbents from proliferating microorganisms on them.For the purification of liquids, in particular milk, from radionuclides used fibrous sorbents on the basis of viscose and ferrocyanides heavy metals (Century. Century. Strelko in. A. Yatsenko, V. K., Martynenko, Century, Minigrant "Fibrous sorbents for the purification of liquid media from radionuclides cesium", J. go active. chemistry, I. 68, V. 9, S. 1456-1460, 1995).However, these sorbents are not effective against strontium, because for them, as for all other above-mentioned adsorbents, it is noted that the presence of calcium ions dramatically reduces the sorption of strontium ions that do not allow them to be used for qualitative treatment of liquids containing calcium ions, in particular milk, from strontium.Closest to the claimed sorbents are based on carbon dioxide margins the liuting, C. M. of Helis, "Comparative evaluation of the selectivity of the sorbents of different types with respect to strontium ions", J. go active. chemistry, I. 67, V. 11, S. 1776-1779, 1994).However, they are suitable for use when cleaning is mainly true solutions, because their kinetic, hydrodynamic and sanitary-hygienic characteristics do not allow to use them for cleaning emulsions milk from radionuclides strontium.The task of the invention consists in expanding the range of sorbents proposed for the sorption of as long-lived radionuclides and toxic heavy metals from liquids, including food emulsions, such as milk.The problem is solved by the sorbent, which is the product of neutralization of acid extraction waste cereals hydroxide of an alkali metal or magnesium, or ammonium, or their carbonates containing 10,0-13,0 wt.% phosphorus and having a density of 1.8-2.0 g/cm3.The proposed sorbents are amorphous substances in white. Their IR spectra are characterized by intense absorption bands in the region of 1200 - 950 and 500-600 cm-1related to the antisymmetric stretching and deformation vibrations of bonds P-O phosphate groups in the sorbent (Nakamoto K.-Infrared and Raman Spectra of Inorganic and Coordination Compounds., N. Y., 1978, p. 142).The proposed sorbent allows you to extract from milk to 65% and from aqueous solutions up to 90% of strontium-85, and also with his help from aqueous solutions are removed almost completely (within the error of the method definition) ions of heavy metals such as lead, chromium, cadmium, etc.For sorbent use waste cereal crops, for example, waste generated during cleaning grain rice, as rice husk or husking bran or mixtures thereof. The acid extract obtained after processing of dilute mineral acid (hydrochloric, sulfuric, nitric or other) waste cereal crops such as rice husk and/or husking bran, neutralize with a solution of a hydroxide of an alkali metal or magnesium, or ammonium, or a solution of their carboxyl salts. The formed precipitate is filtered off and dried. The output of the sorbent is 4-5%.Measurement of the activity of samples in the determination of strontium is performed on the device RKG - P (volume of sample is 75 ml, the coefficient of rationing - 16). Each experiment is carried out in four repetitions, the results are subjected to statistical processing.The effectiveness of aqueous solutions of ions of heavy metals was carried out on the model solutions, the languid-adsorption method in a flame of acetylene-air spectrophotometer AA-780 (Nippon Jharrell Ash) according to the method (Century. Price. Analytical atomic absorption spectroscopy, M.: Mir, 1976, S. 358).IR spectra were recorded on a spectrometer Specord" in the region 400 - 4000 cm-1. The IR spectra of all the samples of sorbents (examples 1-4) are identical and are characterized by absorption bands at 1200 - 950 and 500-600 cm-1(drawing). The asterisk indicates the absorption band of paraffin oil.Example 1. The acid extract obtained by treating rice husking bran with 1% solution of hydrochloric acid (T:W = 1:6), neutralize 25% ammonia solution to pH 7. The precipitate separated from the solution by filtration, washed on the filter with water and dried at 80oC.The output of the sorbent 5% by weight rice husking bran. The sorbent contains of 12.9 wt.% phosphorus has a density of 1.99 g/cm3and IR spectrum similar to that shown in the drawing.Example 2. The acid extract obtained analogously to example 1, neutralize 10% solution of magnesium carbonate. The formed precipitate is filtered off, washed on the filter with water and dried at 80oC.The sorbent yield is 5% by weight rice husking bran. The sorbent contains 13.0% of phosphorus, has a density of 1.80 g/cm3and IR spectrum similar to that shown in the drawing.
oC.The sorbent yield is 5% by weight rice husking bran. The sorbent contains 10.7% of phosphorus, has a density of 1.90 g/cm3IR spectrum similar to that shown in the drawing.Example 4. The acid extract obtained analogously to example 1, neutralize 10% solution of potassium hydroxide. The formed precipitate is filtered off, washed on the filter with water and dried at 80oC.The sorbent yield is 5% by weight rice husking bran. The sorbent contains 12.0% phosphorus, has a density of 1.81 g/cm3IR spectrum similar to that shown in the drawing.Example 5. 2 g of adsorbent with a particle size of 0.25-0.5 mm, obtained according to example 1, placed in 100 ml pre-skimmed milk and a sample is heated with mechanical stirring to a temperature of 90 + 2oC, maintained at this mode for 10 minutes, then quickly cooled in an ice bath to 6 - 8oC with constant stirring. Filtering a measured sample passes through the Mylar filter.The recovery efficiency obtained sorbent strontium-85 reaches 65%.Example 6. 2 g of sorbent, obtained according to the application in the water sorbent is carried out mixing of the sample at room temperature for 1 h in the apparatus with the frequency of rotation of 60 rpmThe efficiency of extraction of strontium-85 is 89%.Example 7. 100 ml of the model solution containing 100 μg/ml of lead, placed 2 g of sorbent, obtained according to example 3 is stirred for 1 hour filtered off and the filtrate determine the remaining amount of lead.The sorption efficiency is 100% within the accuracy of the experience.Example 8. Perform analogously to example 7, however, the extracted metal is cadmium and the adsorbent obtained in example 4.The efficiency of sorption is 99,8%.Example 9. Cleaning is subjected to 100 ml of the model solution which contains at 33 μg/ml of lead, cadmium and chromium. Use sorbent, obtained according to example 1.The efficiency of sorption for all metals is 100% within the accuracy of the experience.Thus, the inventive sorbent derived from cheap and available raw materials, which are waste of grain production, has properties that allow a high degree of effectiveness to use it when cleaning up any liquids, representing himself as a true solution or a food emulsion, from long-lived radionuclides, and so is causesa fact, he is the product of neutralization of acid extraction waste cereals hydroxide of an alkali metal or magnesium, or ammonium, or their carbonates, contains 10,0 - 13,0 wt.% phosphorus and has a density of 1.8 - 2.0 g/cm3.
FIELD: methods of production of a sorption material for purification of water.
SUBSTANCE: the invention is dealt with the methods of production of a sorption material for purification of water in particular, with a method of production of a sorption charge on the basis of a natural sorbent. The method of production of a sorbent for purification of sewage provides for comminution of a wood produced from a stump wood extracted from a peat deposit, after which it is separated by fractions and treated with a solution of a mineral acid with consequent stacking the treated reduced wood in a filtering installation. At that in direction of the traffic route of the stream of filtration the sizes of the wood fractions are increasing. The sorbent charge is effective at purification of industrial, household and surface sewage simultaneously from suspended substances, oil products, colloidal - dissolved forms of salts and ions of heavy metals, organic impurities.
EFFECT: the invention ensures production of sorbents effective at purification of industrial, household and surface sewage simultaneously from suspended substances, oil products, colloidal-dissolved forms of salts and ions of heavy metals, organic impurities.
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