Method of purification of diamond synthesis products at extraction of metallic nickel and manganese
FIELD: electrochemical extraction of metals from complex compounds; purification of diamond synthesis products.
SUBSTANCE: proposed method includes electrochemical treatment of synthesis product in acid electrolyte for obtaining graphite-diamond product containing 0.5-2.0% of metallic admixtures and deposition of metallic nickel and manganese on cathode. During purification of diamond synthesis products at extraction of nickel and manganese in form of metallic product, electrochemical treatment is carried out in membrane-type electrolyzer at circulation of catholyte through second electrolyzer. Process is conducted in area of temperatures of 25-30°C at cathode current density in the first electrolyzer of 2-15 A/dm2 and 15-30 A/dm2 in the second electrolyzer; catholyte pH in the presence of 100-150 g/l of (NH4)2SO4 in it is maintained at outlet from the first electrolyzer of 5-7.5 and 2.5-5 at return.
EFFECT: possibility of performing nickel and manganese extraction and purification of diamond synthesis products in one cycle.
1 tbl, 6 ex
The invention relates to an electrochemical separation of metals from materials of complex composition, in particular to a method of cleaning products for the synthesis of diamonds, and can be used at the enterprises of diamond tools for the production of synthetic diamonds.
Synthetic diamond powders are widely used in the manufacture of abrasive tools and pastes, medical instrument, upon receipt of an electrolytic composite coatings in the manufacture of rubber products, electronics industry and so on
The synthesis of diamond from graphite at high temperatures and pressures in the presence as catalyst of a metal alloy, in particular an alloy containing 40% Ni and 60% Mn. The original charge for carrying out synthesis has the composition: 50% graphite and 50% of the alloy Ni-Mn. During the synthesis of 40-50% of the graphite is converted to diamond. Reaction sintered product of the synthesis of diamond (PSA) - typically contains: 20-25% of the diamond, 20% Ni, 30% Mn and the rest supercriticalities graphite. The final and most difficult stage in the process of getting diamonds is their cleaning, which is considered a limiting factor in the growth of production of synthetic diamond powder.
To clean diamonds from carbon and metal impurities are various physical and chemical methods, which are detailed is described in the scientific literature [see, for example, V.A. Mukhanov Improved methods of extraction of diamonds from a variety of diamond-containing materials. Superhard materials. 2003, №4, p.16-26; Vereshchagin A.L., Larionov I.S. Cleaning diamonds / Polzunov almanac, No. 3, 1999); Isaev R.N. Methods of extraction of diamonds from various materials and methods for their purification. Superhard materials, 1989, No. 2, pp.30-34]. Sintered crushed and milled to a particle size - 2-0,8 mm, metal impurities leached mineral acids and their mixtures, then the main part of the graphite is removed mechanically, in particular by gravity methods. At the final stage for cleaning diamond powder from residual graphite it is treated with various oxidants, mainly chromic acid mixture (solution chromic anhydride or bichromate of potassium in concentrated sulfuric acid). If necessary, the resulting product is subjected to more fine cleaning of silicon and its compounds with the use of fluorine-containing reactants.
The most expensive link in the purification of synthetic diamonds is the stage chemical leaching of metals with acid solutions. It is associated with significant consumption of acidic reagents, significant ecological impact on the environment and irrecoverable loss of the entire Nickel and manganese from the waste acid solutions. Existing FPIC who would used for cleaning synthetic diamond powders, do not allow to solve this problem.
Some studies have attempted to extract the Nickel and manganese from sulfate solutions by electrodialysis method [see, for example, A. M. Levin, V.A. Bryukvin, Wolson L.M., Anufrieva GI Extraction of Nickel and manganese from sulphate solutions using membrane electrodialysis. "Non-ferrous metals", 2000, No. 2, p.41-44; G.P. Bogatyreva, Marinich M.A., basali GA Allocation of Nickel from solutions after extraction of superhard materials. "Superhard materials, 1984, No. 3, page 11-14]. However, these developments do not provide the necessary degree of metal extraction and regeneration of the used acid reagent.
Known electrochemical leaching DOG with the transfer of metals in solutions [see Drozdovich V.B. have been, smoked I.I. Study of chemical and electrochemical decomposition metallogidridnyh class of diamond synthesis. Powder metallurgy (Republican interdepartmental collection of scientific works - Belarus), issue 21, 1998, p.34-37]. In this work shows the possible processes at electrochemical decomposition of the DOG and the feasibility of using for this purpose solutions of sulfuric and hydrochloric acids. The work is exemplary in nature and not given technological parameters on the extraction and the other is m important process parameters.
The closest technical solution is the electrochemical processing of the product of synthesis of diamonds with kattnig deposition of metals [see, for example, G.P. Bogatyreva, Marinich M.A., basali G.A. investigation of the influence of the nature of metals solvents on the kinetics of electrochemical dissolution of the product of synthesis of diamonds. Superhard materials, 1999, No.1, p.59-65]. The process is based on the anodic dissolution of metals from the DOG in hydrochloric acid or sulfuric acid electrolyte in the temperature range of 40-60°in the electrolyzer, in which there is simultaneous selection of the metal at the cathode. The disadvantages of this process include low extraction of manganese due to high temperature and strong acidity of the electrolyte, the misclose cycle due to accumulation in the electrolyte of manganese and, as a consequence, the need for disposal of waste electrolyte after each cycle.
The proposed method allows you to virtually eliminate these drawbacks. This is achieved by using electrochemical treatment of PSA in membrane electrolyzer circulation Catolica (electrolyte cathode chamber). As in the prototype, the electrolyte used sulfuric acid, hydrochloric acid solutions or mixtures thereof. The concentration of Nickel and manganese in the electrolyte changes during the process depending on the pH of rest the ditch. The proposed method allows to quantitatively extract the Nickel and manganese from the DOG in the form of metal with simultaneous receipt of graphite-diamond product suitable for further processing by the known technological scheme.
Determinants of electrochemical processing of the DOG in the membrane electrolyzer circulation Catolica are pH Catolica, process temperature, cathode current density, the content in the electrolyte (catholyte) ammonium sulfate.
The essence of the proposed method lies in the fact that the electrochemical treatment of the DOG in the membrane electrolyzer circulation Catolica allows you to combine three processes in a single cycle: 1 - oxidation in the anode chamber under the influence of the anode current of Nickel and manganese from the DOG with their transition into the solution. In the case of using sulfuric acid electrolyte is also partial oxidation of graphite to carbon dioxide; 2 - transition under the influence of the cathode current of ions of manganese and Nickel through cation membrane from the anode chamber into the cathode and their deposition on the cathode, mainly Nickel, as more passive metal in comparison with manganese. Constant replenishment of Catolica ions Ni2+from the anode chamber restricts the discharge of manganese ions on the cathode, the catholyte is gradually saturated with ions of Mn2+and the pH of the electrolyte is increased; 3 - the transfer of Catolica in another cell where the cathode is deposited manganese residual Nickel, resulting in a decrease in pH of the electrolyte and the return of Catolica from the second cell in the first by circulating a solution that allows you to maintain the pH at the required level.
After complete dissolution of metals from the anode chamber is unloaded the remainder, representing a mixture of diamond from graphite. The residue is filtered, washed with water and sent for processing to obtain diamond powder by known scheme. The mother liquor from the washing water is returned to the anode chamber for reuse. Highlighted on the cathode metals removed, washed, dried, and as a commercial product (after processing) is used in the synthesis of synthetic diamonds. Catholyte without any additional operations used in the next cycle. The result is an environmentally friendly waste-free closed cycle, allowing to extract diamonds from the DOG while removing the metal-supported catalysts.
In the proposed method, the electrolyte used hydrochloric acid, sulfuric acid solution or a mixture thereof. pH Catolica has a very strong influence on the deposition of metals, particularly the deposition of manganese. In acidic and weakly acidic rest the arts facilitated the evolution of hydrogen. Only at pH 2 starts the deposition of manganese metal at the cathode. With increasing pH the current output of manganese increases. However, at high pH values (5-8,5) are formed hydroxides and basic salts of manganese and Nickel. To prevent the formation of hydroxide, manganese and Nickel in the electrolyte is injected ammonium sulfate in the amount of 50-175 g/l, more preferably 100 to 150 g/l, as taken in the electrolytic production of manganese. With a shortage of ions NH4 +is the binding of manganese ions at the cathode in Mn(OH)2, when a large excess is allocated hydrogen as ammonium ions are the source of hydrogen, and the current output of the manganese is reduced. In the proposed method, the optimal pH values of circulating Catolica are: when the output from the first cell - 3-8,5, more preferably 5-7,5, when the return - 2-7, more preferably 2.5 to 5.
The temperature of the electrolyte is maintained at 20-35°S, more preferably 25-30°C. the Increase of temperature promotes rapid amplification of hydrogen, and therefore the suppression of the cathodic deposition of manganese. And at lower temperatures significantly slow down the processes of dissolution of metals from the DOG in the anode chamber, and discharge of ions of manganese and Nickel on the cathode due to the deterioration of the kinetic terms.In the proposed method, the duration of the process depends mainly on the cathode current density. The process in membrane electrolysis is carried out at a cathode current density of 2 to 30 A/DM2more preferably, in the first cell, where mainly the deposition of Nickel - 2-15 A/DM2and in the second cell, where the deposition of manganese with residual Nickel - 15-30 A/DM2. At lower values of current density is strongly limited by the cathodic deposition of metals, and at high values - increases the release of hydrogen, which in turn decreases the current output of metals. The optimal duration of the process at specified values of cathodic current density varies in the range of 8-15 hours. After the process is complete, the total content of Nickel and manganese in the graphite-diamond product is reduced to 0.5 to 2.0%. The degree of extraction of metals from the DOG reaches 98-99,5%.
Further purification released from metallic impurities product synthesis with getting the diamond powder is the standard scheme: gravity concentration with removal of much of the graphite, and then fine chemical cleaning by treatment in chromic acid mixture.
The main results achieved by the electrochemical machining of a DOG with the extraction of diamonds and simultaneous achievement of metals to the of talization by the proposed method shown in the table.
The following examples illustrate the possibilities of the proposed method (these examples in the table in bold; indices 1-6 at room experience denote respectively the number of examples).
Example 1. A portion of a DOG weighing 100 g was placed in the anode chamber membrane of the cell and subjected to sulfuric acid environment of the electrochemical treatment at a temperature of 25°C for 15 h circulation Catolica through another cell. Cathode current density in the first cell was 2 A/DM2and in the second cell 15 A/DM2. the pH of the circulating Catolica containing 100 g/l (NH4)2SO4when the output from the first cell poderzhevala at the level of 6.5, and when you return at the level of 4.0. Received of 46.4 g of graphite-diamond product containing 1,13% metal. The extraction of Nickel and manganese from the DOG amounted to 91.4%.
Example 2. A portion of the DOG was treated at a temperature of 30°C for 12 h in membrane electrolyzer according to the above method. Cathode current density in the first cell to 5.0, in the second to 20.0 A/DM2. Contents (NH4)2SO4in the electrolyte 125 g/L. pH Catolica when the output from the first cell to 5.0, and when you return to 2.5. The mass of the obtained graphite-diamond product amounted to 50.5 g, and metallic Nickel and manganese - 48,1, Removing the metal is in from DOG 96,2%.
Example 3. The experiment was carried out in sulfuric acid environment in the following mode: temperature - 30°C, duration - 10 hours, the cathodic current density in the first electrolyzer - 10,0 A/DM2and the second 25 A/DM2the content of (NH4)2SO4in the electrolyte 150 g/l, pH Catolica when the output from the first cell is 7.5, and when returning to 5.0. When this is achieved the degree of extraction of metals from DOG 98,8%.
Example 4. The electrolyte composition and process temperature as in example 3. Cathode current density in the first and second electrolytic cells - and 15,0 30,0 A/DM2pH of Catolica when I exit and return of 7.0 and 3.5, respectively. The duration of the experiment 8 hours. As a result of 48.7 g of graphite-diamond product when the degree of extraction of the metals of 99.5%.
Example 5. Was used hydrochloric acid electrolyte. The experiment was carried out in the same way as in example 3. The output of the graphite-diamond product accounted for 50.2 g, and metals 48,9, the Degree of extraction of metals from the DOG of 97.8%.
Example 6. The experiment was carried out in a mixed electrolyte - sulfuric acid: hydrochloric acid = 1:1. Contents (NH4)2SO4in the electrolyte - 100 g/L. the Parameters of the process are similar to the settings shown in example 4. The output of the graphite-diamond product and metals from DOG to 48.5 g and 49,1,, respectively. Extraction of metals is 98.2%.
The main advantages of the proposed method zaklyuchayut what is the purification processes of the DOG from metallic impurities of manganese and Nickel, and the extraction of these metals occur simultaneously in a closed solutions environmentally friendly a single cycle. Thanks regeneration used in the synthesis of metal-supported catalysts, especially the expensive Nickel, and eliminate the formation of waste acid solutions in the process of cleaning the DOG, using the proposed method will significantly increase the volume of production of synthetic diamond powders without the environmental impact on the environment.
The method of purification of products of synthesis of diamonds with the extraction of metallic Nickel and manganese, including electrochemical processing of product synthesis in acidic electrolyte with the selection of the metal on the cathode, wherein the electrochemical process is carried out in a membrane electrolyzer with a circulation of Catolica through the second cell and the process is conducted in the temperature range of 25-30°at a cathode current density in the first cell 2-15 A/DM2in the second cell 15 to 30 A/DM2and pH Catolica in the presence of 100-150 g/l (NH4)2SO4support when the output from the first cell within 5-7,5, and upon return of 2.5 - 5.
FIELD: treatment of diamonds.
SUBSTANCE: proposed method of change of diamond color includes the following stages: (i) forming reaction mass at presence of diamond in pressure-transmitting medium fully surrounds the diamond; (ii) subjecting the reaction mass to action of high temperature and pressure during required period of time; proposed diamond is brown diamond, type IIa; its color is changed from brown to colorless by subjecting the reaction mass to action of temperature of from 2200°C to 2600°C at pressure of 7.6 Gpa to 9 Gpa.
EFFECT: possibility of keeping diamond intact during treatment.
46 cl, 4 dwg, 1 ex
FIELD: treatment of diamonds.
SUBSTANCE: proposed method includes the following stages: (i) forming of reaction mass at presence of diamond in pressure-transmitting medium fully surrounding the diamond and (ii) action of reaction mass by high temperature and pressure during required period of time; diamond is of IIb type and its color is changed from gray to blue or dark blue or is enriched by action on reaction mass of temperature from 1800°C to 2600°C at pressure of from 6.7 GPa to 9 GPa (first version). Diamond of type II may be also proposed which contains boron and its color is changed to blue or dark blue by action on reaction mass by the same temperature and pressure (second version).
EFFECT: improved color of diamond by changing it from gray (brown-gray) to blue or dark blue.
31 cl, 4 dwg, 2 ex
FIELD: treatment of natural diamond for change of its color.
SUBSTANCE: proposed method includes the following stages: (i)forming of reaction mass at presence of diamond pressure-transmitting medium which fully surrounds it; (ii) action on reaction mass by high temperature and pressure during required period of time; proposed diamond is brown diamond, type IIa; its color is changed from brown to rose by action on reaction mass by temperature from 1900°C to 2300°C at pressure from 6.9 GPa to 8.5 GPa.
EFFECT: enhanced efficiency of enriching diamond color keeping its crystals intact.
30 cl, 4 dwg, 1 ex
FIELD: processes and equipment for working natural and artificial origin diamonds, possibly in jewelry for refining diamonds and for imparting to them new consumer's properties.
SUBSTANCE: method comprises steps of acting upon crystal with electron beam whose integral flux is in range 5 x 1015 - 5 x 1018 electron/cm2; annealing crystal in temperature range 300 - 1900°C and acting with electron beam in condition of electric field having intensity more than 10 V/cm at least upon one local zone of crystal for imparting desired color tone to said zone. Local action of electron beams is realized through protection mask. As irradiation acts in condition of electric field local flaws such as bubbles or micro-inclusions are effectively broken.
EFFECT: possibility for producing diamonds with different local three-dimensional colored images such as letters or patterns of different tints and color ranges.
FIELD: advanced techniques for creating diamonds, possibly micro- and nano-electronics for creating new super-strength construction materials widely used in different branches of industry, for producing semiconductor diamond base light emitting diodes, jewelry articles.
SUBSTANCE: diamond synthesis method comprises steps of irradiating carbon-containing materials with fluxes of magnetic mono-fields generated from plasma for time period determined by motion speed of magnetic mono-fields through irradiated material. Such process does not need high-pressure chambers, special heating members and it is possible to realize it at atmospheric pressure and room temperature or in vacuum.
EFFECT: possibility for producing high-purity diamonds of predetermined size and shapes.
FIELD: mineral dressing.
SUBSTANCE: method comprises charging, chemically enriching concentrate, cleaning, and discharging desired product. Chemical enrichment is carried out by way of single or multiple processing in acid or in acids and then in alkali or alkali mixture, while heating material to 900-1000°C and holding it at this temperature in inert gas medium at stirring.
EFFECT: enhanced diamond cleaning efficiency.
6 cl, 1 tbl
FIELD: production of diamonds of jewelry property; high-quality cleaning of diamonds.
SUBSTANCE: proposed method includes stage-by-stage treatment of diamond by mixture of acids under action of microwave radiation; at first stage, use is made of nitric acid and hydrogen peroxide at volume ratio of components of 10:1, respectively; at second stage, volume ratio of mixture of concentrated nitric acid, hydrochloric acid and hydrofluoric acid is 6:2:1, respectively; diamond is treated at temperature not higher than 210°C, pressure of 35 atm as set by loading ratio of autoclave equal to 1:10 at power of oven of microwave radiation of 1200 W; duration of each phase does not exceed 40 min. Proposed method ensures perfect cleaning of diamonds from contamination of mineral and organic nature including bitumen compounds on surface and in cracks of diamond.
EFFECT: enhanced efficiency; reduction of time required for process.
FIELD: jewelry industry, in particular, production of precious stone, more particular diamond which may be personified or identified with certain individual or animal.
SUBSTANCE: personified grown jewelry diamond comprises heavy metals Sr, Cd, Sn, Ba, Pb, Bi separated from hairs of certain individual or animal, with ratio of concentrations of said metals corresponding to that of said elements in hairs of the given individual or animal. Method involves processing hairs of certain individual or animal by mineralization of hairs at temperature below 550 C until complete decomposition of organic component; forming source for growing of diamond from spectrally pure graphite and hair processing product containing heavy metals Sr, Cd, Sn, Ba, Pb, Bi; growing diamond from melt by seed crystal recrystallization process; determining ratio of concentrations of these elements in grown diamond and comparing with their content in processing product. Jewelry diamond produced has microelements characteristic of certain individual or animal.
EFFECT: simplified method and improved quality of grown jewelry diamond.
3 cl, 2 tbl
FIELD: decolorizing diamonds and brilliants.
SUBSTANCE: method is realized due to physically acting in closed reaction space upon samples of diamonds and brilliants by means of high pressure and temperature for time period sufficient for enhancing their quality. Pressure acting upon samples is in range 6 - 9 GPa in region of thermodynamic stability. Temperature during physical action upon samples is in range 1700 - 2300°C. Samples are subjected to physical action in medium of graphite powder filling reaction space. Heating till high temperature is realized due to applying AC to samples of diamond or brilliant through graphite powder at specific electric current power from 0.18 kWt/cm3 and more. Then electric power is gradually increased from zero till working value and further it is decreased and increased at least two times for some time interval at each change of electric power. Process of annealing samples is completed by smoothly lowering electric current power till zero. At physical action upon sample electric current intensity is lowered by 11 - 13 % and it is increased by 15 - 17 % for time interval from 8 min and more at each change of electric power. Sample is AC heated and it is cooled at rate no more than 0.05kWt/min per cubic centimeter of reaction volume of chamber.
EFFECT: shortened time period of treating for whole decolorizing, lowered voltage values, keeping of desired parameters existing before treatment in diamonds and brilliants.
3 cl, 3 ex
FIELD: production of the jewelry quality diamonds from the natural low-grade undecoratively colored diamonds.
SUBSTANCE: the invention is pertaining to production of the diamonds of the jewelry quality from the natural low grade undecoratively colored so-called "brown" diamonds, especially from the diamonds of IIa type and IaA/B type, in which nitrogen forms predominantly B-center for improvement of heir color. The invention provides for realization of the rough faceting and molding of the undecoratively colored natural diamond for giving it the streamline form to avoid its breakup in the press of the high-pressure and heating (HP/HT press). The indicated undecoratively colored natural diamond is put in the pressure transferring medium, which then is compacted into the tablet. Then the tablet is put in the HP/HT squeezer under the high pressure and temperature kept in the field of stability of the blacklead or the field of stability of the diamond of the phase diagram of carbon for the time duration sufficient for improvement of the color of the diamond. After the operation is terminated extract the diamond from the squeezer. The method ensures production of the colorless and decoratively colored diamonds.
EFFECT: the invention ensures production of the colorless and decoratively colored diamonds.
25 cl, 6 ex, 2 dwg
FIELD: carbon materials.
SUBSTANCE: invention concerns manufacture of diamond films that can find use in biology, medicine, and electronics. Initial powder containing superdispersed diamonds with level of incombustible residue 3.4 wt %, e.g. diamond blend, is placed into quartz reactor and subjected to heat treatment at 600-900оС in inert of reductive gas medium for 30 min. When carbon-containing reductive gas medium is used, heat treatment is conducted until mass of powder rises not higher than by 30%. After heat treatment, acid treatment and elevated temperatures is applied. Heat treatment and acid treatment can be repeated several times in alternate mode. Treated powder is washed and dried. Level of incombustible impurities is thus reduced to 0.55-0.81 wt %.
EFFECT: reduced level of incombustible impurities.
4 cl, 3 ex
FIELD: carbon materials.
SUBSTANCE: weighed quantity of diamonds with average particle size 4 nm are placed into press mold and compacted into tablet. Tablet is then placed into vacuum chamber as target. The latter is evacuated and after introduction of cushion gas, target is cooled to -100оС and kept until its mass increases by a factor of 2-4. Direct voltage is then applied to electrodes of vacuum chamber and target is exposed to pulse laser emission with power providing heating of particles not higher than 900оС. Atomized target material form microfibers between electrodes. In order to reduce fragility of microfibers, vapors of nonionic-type polymer, e.g. polyvinyl alcohol, polyvinylbutyral or polyacrylamide, are added into chamber to pressure 10-2 to 10-4 gauge atm immediately after laser irradiation. Resulting microfibers have diamond structure and content of non-diamond phase therein does not exceed 6.22%.
EFFECT: increased proportion of diamond structure in product and increased its storage stability.
FIELD: chemical industry and electronics; production of diamonds.
SUBSTANCE: the invention is intended for chemical industry and electronics. The chemical product is prepared out of the following organic compounds (in weight %): acetamide - 6.7; carbamide - 0.8; ethylene glycol - 2.0; glycolic acid - 11.7; lactamide - 8.8; glycerine - 2.3; hexamethylenetetramine - 11; indene - 7.6; 1,2-dimethylnaftaline - 2.6; 1,4 -diisopropenylbenzol - 3.3; cyclohexylphenylketon - 8.1; 4'-cyclohexylacetophenone - 7.2; 4-(1-adamantyl)phenol - 2.1; 4,4'-methylenebis (2,6-dimethyl phenol) - 2.3; α,α'- bis (4-hydroxyfenyl)-1.4-diisopropylbenzol - 0.2; phenanthrene - 11.0; lauric acid - 6.2; sebacic acid-6.3; eicosanic acid - 9.7. The indicated components are mixed with water in the ratio of 1:(1-2). The mixture is heated up to 150-200°С in vacuum of 10-1-10-6Pa. A reaction sample formed this way is refrigerated in conditions of vacuum and dried for removal of water and the volatile organic substances. The dried reaction sample is heated in vacuum up to 200-400°С for 80 hours. The invention allows to use the raw material being in lower power state as compared with the known methods and to produce the high-clean diamonds.
EFFECT: the invention ensures production of the high-clean diamonds from the raw material of the lower power state.
16 cl, 1 tbl, 1 ex, 4 dwg
FIELD: production of color diamonds.
SUBSTANCE: the invention is pertaining to the field of production of fantasy neon yellow-green diamonds of precious quality produced from the pale (discolored) or so-called "brown" diamonds of the lowest quality. The method provides for placement of a pale natural diamond in the medium capable to transfer the pressure, which then is mold into a "tablet". Then the tablet is placed in the high-pressure press (HP/HT) and exposed to machining at an increased pressure and temperature being within the range of graphite stability or a diamond being on the phase diagram of carbon for the period of time necessary for improvement of a color of the mentioned diamond. In the end the diamond is removed from press. The indicated method ensures production of diamonds of an attractive yellowish-green or yellow-green and neon yellow-green colors.
EFFECT: the invention ensures production of diamonds of attractive yellow-green colors.
22 cl, 4 ex, 2 dwg
FIELD: chemical industry.
SUBSTANCE: the invention is intended for chemical industry. To 1 g of a powder of nanodiamonds of an explosive synthesis add 100 ml deionized water. The mixture is treated with the ultrasonic dispersant for 5 minutes. The produced suspension is added with an electrolyte - NaCl solution in the quantity exceeding sorptive capacity of nanoparticles by ions of sodium, for example, 20 ml of 0.9 M solution. Then separate the disperse medium and the settling. The disperse medium is removed. The settling is added with 100 ml of deionized water and is intensively agitated. The supernatant - hydrosol of nanodiamonds is separated and dried. At multiple add-on of water to the produced powder a stable nanodiamond hydrosol is formed. The share of the surface impurities in the produced nanodiamond is reduced. Simultaneously the share of sodium ions is increased.
EFFECT: the invention allows to reduce the share of the surface impurities in the produced nanodiamond and simultaneously to increase the share of sodium ions.
1 dwg, 1 tbl
FIELD: carbon materials.
SUBSTANCE: invention is designed for use in manufacture of hydrosols, organosols, and suspensions in oils. Nano-size diamond powder is charged into ultrasonic disperser and water and modifier, in particular organic ligand such as EDTA or ethylenebis(oxyethylenenitrilo)tetraacetic acid are then added. Resulting suspension is separated on centrifuge into dispersion medium and precipitate. The latter is treated with water to form suspension, which is centrifuged to give precipitate and hydrosol, which are concentrated separately by heating in vacuum into powderlike form. When concentrating hydrosol, depending on desire, following finished products may be obtained: concentrated hydrosol, cake, or dry black powder. When concentrating precipitate, clear nano-size diamond powder is obtained. Thus obtained products are appropriate to prepare sedimentation-resistant hydrosols and organosols with no ultrasound utilized, which products have no tendency to aggregate upon freezing and thawing, boiling and autoclaving, and which can be repetitively dried and reconstituted. Surface pollution of nanoparticles is reduced.
EFFECT: enabled preparation of hydrosols with precise concentration of nano-size diamonds.
3 cl, 1 tbl, 5 ex
SUBSTANCE: method comprises filling tank (11) with coolant (12) and igniting heating mixture (3) say silicon boride. At the moment of maximum heating of the graphite (5) to be processed, explosive (1), say trinitrotoluene, is initiated. The propagating explosion wave set heated mixture (3) and agent (5) to be processed into motion, and agent (5) enters closed passage between the cooled separated substrate (8) and rod (9). The passage can be diverging to provide additional compression of agent (5) and pressing substrate (8) into conical mandrel (1) under the action of shock wave. Deflecting diaphragm (7) is an insulator, and insulating layer (2) prevents agent (5) to be ignited up to the moment of its maximum heating.
EFFECT: enhanced efficiency and reduced power consumption.
1 cl, 2 dwg
FIELD: power industry, mechanical engineering and environmental control.
SUBSTANCE: the invention is pertaining to the field of high power industry, mechanical engineering and environmental control. In a explosion-proof chamber 1 with double-walls simultaneously feed a gaseous explosive mixture using pipeline 4 through channels 5 and inject hydrocarbons with the nucleuses of carbon crystallization using a pipeline 6 through an injector 7 with formation of a cone-shaped shell 8 with an inert cavity in the central zone. The shell 8 and the explosive mixture 9 form a cumulative charge. Conduct initiation of undermining of an explosive mixture 9, as a result of which the cumulative charge forms a cumulative spray 10 moving at a high speed along the axis of the cumulation. The gaseous products withdraw through pipeline 17. At collision of the cumulative spray 10 with a barrier having channels 11 of the cooling unit 2 the pressure and temperature there sharply increase ensuring growth of the formed crystals of diamond. Simultaneously conduct cooling with the help of pipelines 12 located in metal filings and granules 13. The atomized and cooled cumulative spray gets into the auxiliary chamber 3, where the diamonds 14 are separated, feed through the pipeline 15 to a power accumulator 16, in which they are settling. Separated hot hydrogen is removed for storing or utilization. The invention allows to magnify the sizes of dimensions crystals of diamond up to 800 microns and more, to decrease atmospheric injections, to reduce the net cost of the diamonds, to increase effectiveness of the device.
EFFECT: the invention ensures growth of sizes of diamonds crystals up to 800 microns and more, decrease of atmospheric injections, reduction of the net cost of the diamonds, increased effectiveness of the device.
2 cl, 2 dwg
FIELD: methods and devices used for production of diamonds.
SUBSTANCE: the invention is pertaining to methods and devices for production of diamonds and may be used in materials technology. Assemble a mold. Ignite a thermit grain and heat up the powdered graphite. After that they initiate explosion of a charge. The explosion energy sets in motion a striker, which is directly caulking the powder graphite in the capsule. After that disassemble the mold, extract the produced diamond. The invention allows to miniaturize the sizes of the charge and the mold, to simplify the production process and to use such a mold multiply.
EFFECT: the invention allows to miniaturize the charge and the mold sizes, to simplify the process of diamonds production and to use such a mold multiply.