Method of processing detonation carbon (versions)
SUBSTANCE: invention relates to modification of properties of superhard materials and can be used in synthesis highly pure ultradisperse diamonds. Detonation carbon is processed in supercritical water or in supercritical water with addition of hydrogen peroxide.
EFFECT: modification of surface of nanoparticles of condensed carbon phase containing ultradisperse diamonds, removal and decomposition of non-diamond carbon structures, environmentally safe non-waste technology.
2 cl, 2 dwg, 2 ex
The invention relates to the field of modification of properties of superhard materials, namely spraying detonation of carbon (charge detonation of carbon-containing ultrafine nanodiamonds)obtained by the method of detonation synthesis in the explosion of the solid carbon-containing explosives with negative oxygen balance, and may find application in the preparation of ultra-dispersed diamond of high purity.
Studies of carbon nanostructures in the development of new nanotechnologies recently given much attention. Among the various synthesized carbon structures should be allocated so-called ultra dispersed nanodiamonds (UDA)obtained by the method of detonation synthesis with the detonation of the solid carbon-containing explosives [Aiyin, Ehapter, A.P. Ershov, Gavranovic, Ametuer, V.m.titov. Dokl. Academy of Sciences, 1988. 302, 611]. Despite the high performance of this method we obtain the product of detonation soot or carbon contains various patterns and forms of carbon, including the content of the diamond phase is only 35-45 wt.%. Moreover, depending on the production technology [O.A.Shenderova V.V.Zhirnov D.W.Brenner. Carbon nanostructures. In Critical Reviews in Solid State and Materials Sciences. 2002. 27. 3/4 / P.227-356; Woodyates. Ultradisperse diamonds of detonation synthesis: properties and application. The success khimii, 70, 7. 687-708]in detonation soot may contain adsorbed impurities in the form of metals, oxides and carbides.
To highlight the diamond phase or UDA initial charge, usually liquid or gaseous oxidants. As a liquid oxidant is a mixture of sulfuric and nitric acids, sulfuric and chromic anhydride [Woodlots. Ultradisperse diamonds of detonation synthesis: properties and application. The USP. 2001, 70, 7. 687-708]. Oxygen and ozone are also used as gaseous thermocycles. In practice, the most used method of treatment of the mixture with concentrated nitric acid under temperature and pressure conditions in the autoclave at high pressure and temperature. This method allows to oxidize Almazny carbon and remove metals, their oxides and some other impurities. Purified by this method, the powder may contain up to 90-97 wt.% various forms of nanodiamonds and 3-10 wt.% non-diamond carbon and other impurities.
The main disadvantages of the known methods of chemical and mechanical cleaning using strong acids and oxidizers should include the allocation of a large number of aggressive waste, as well as oxidation of the diamond phase.
There is a method of removal of non-diamond carbon [of the Russian Federation No. 2132816, C01B 31/06, B01J 3/04, 10.07.99], in which the cleaning almasoud Rasa mixture is held when it is heated to a temperature of 320-400°C with potassium nitrate for 30 minutes The disadvantage of this approach is the presence in the treated sample of potassium oxide (melting point of which 740°C), which is the product of the decomposition of potassium nitrate.
There is a method of allocation of ultradispersed diamonds, we adopted for the prototype [of the Russian Federation No. 2109683, C01B 31/06, 27.04.1998], in which cleaning of the diamond-containing mixture from various impurities and the allocation of ultradispersed diamonds is carried out in the two-stage treatment with an aqueous solution of nitric acid at high temperatures and pressures.
To the main disadvantage of the prototype should include the use of strong acids and, as a consequence, the presence of hazardous waste in the form of acids.
The present invention solves the problem of efficient removal of non-diamond phase of carbon and process of detonation of carbon without the use and formation of harmful, toxic compounds and substances.
The technical result - surface modification of the nanoparticles condensed carbon phase containing ultrafine diamonds, removal and decomposition of non-diamond carbon structures, creating an environmentally friendly waste-free technology.
The problem is solved in two variants of the method of processing the detonation of carbon.
In the first embodiment processing detonation of carbon is carried out in supercritical water (SLE).
The second option clicks the processing detonation of carbon is carried out in supercritical water (SLE) with the addition of hydrogen peroxide.
Many of the substances in supercritical conditions are effective reaction medium for various chemical transformations and show unusual properties, which allows for variations of temperature, pressure and residence time at high speed to carry out chemical reactions. Among supercritical solvents most attention of researchers is water (RRC=22 MPa, Tcrit≈374°C) due to the fact that supercritical water - SLE is a multi-component medium consisting of a weakly interacting polar molecules H2O and nanoparticles condensed phase neutral and charged clusters (H2O)nH+(H2O)i, OH-(H2O)j. Properties of a supercritical fluid water depend on density, temperature, composition and concentration of impurities, and can change when an external impact, for example, force fields, hydrodynamic perturbations. The dissociation constant of water near the critical point in three times more constants for water in its normal state and, thus, near the critical point has a large concentration of ions H3O+and OH-than water in its normal or subcritical conditions. Therefore, the water in this state can show properties of acid and basic catalysis. But, should it is to emphasize, such properties are preserved only near the critical point. Among the chemical reactions carried out in GFR, the most practical use today are oxidation reactions carried out in supercritical water.
The invention is illustrated by the following examples.
Example 1. Processing of samples detonation of carbon in supercritical water.
In the reactor-autoclave with a volume of 45 cm3with electric heating and stirring was placed a sample of the mixture with water and heated with stirring until the temperature of the experiment 390°C (+/-5), pressure - 285(+/-5) ATM. After setting the temperature and pressure corresponding to the water transfer in the supercritical state, the process continues from 4 to 6 hours, After cooling the reactor to measure the pressure and gas volume of the reaction products, the latter increases as compared with the initial 1.5-2 times, indicating that the oxidation of carbon-containing phase. About
80% vol. the resulting gas is CO2in addition, in the reaction products observed some amount of CO, CH4H2. There is loss of mass of the initial charge, which indicates substantial oxidation of the carbon content of the mixture during the process in SLE.
Studies of the solid phase before and after treatment in SLE carried out by electron (HRTEM), (SEM) mi is rescobie, method of x-ray phase analysis (XRD). Using chromatography to analyze the composition of the resulting gaseous reaction products, measure their volume.
The results of x-ray phase analysis
The analysis of diffraction spectra processed in SLE samples shows that the ratio of the integral intensities of the peaks (ID/IGfor this type of processing depends on the process time and increases from the initial value to a value of 0.8 1.1-1.3.
The results of HRTEM analysis.
Figure 1 shows the HRTEM images of detonation of carbon after treatment in SLE. Comparison shots of the charge of the original sample detonation of carbon with the images obtained after processing in supercritical water (Figure 1), showing a significant difference of the latter. First, it significantly decreased the amount of amorphous phase of carbon, secondly, the increased concentration of carbon cubic modification.
Example 2. Processing of samples detonation of carbon in supercritical water in the presence of hydrogen peroxide.
In the reactor-autoclave with a volume of 45 cm3place the sample mixture with water and heated with stirring to a temperature of 300°C, then using a syringe pump is introduced into the reactor under a pressure of 30% aqueous hydrogen peroxide solution in an amount to provide the stoichiometric autochangecolor, formed in the decomposition of hydrogen peroxide (one mol H2O2- 0.5 mole of O2), with non-diamond carbon contained in the original sample mixture.
After the establishment of the stationary temperature 390°C (+/-5) and pressure -285(+/-5) ATM the process continues from 4 to 6 o'clock Processed in SLE in the presence of oxygen formed by the decomposition of hydrogen peroxide, the sample detonation of carbon changes the color from black to grey. Volume of gas evolved taking into account unreacted oxygen exceeds more than 8 times the initial free volume of the reactor.
The results of x-ray phase analysis.
The relationship of the integral intensities processed in SLE in the presence of oxygen samples detonation of carbon vary considerably in the direction of increasing the share of diamond and equal for samples ID/IG=1.35-1.86, which corresponds to 65-75 wt.% diamond phase.
The results of HRTEM analysis.
Figure 2 presents HRTEM images detonation of carbon after treatment in SLE in the presence of the decomposition products of hydrogen peroxide. Analysis of HRTEM images of samples detonation of carbon after it is processed in supercritical water with the participation of the decomposition products of hydrogen peroxide showed, first, a high degree of purification. 2, secondly, the practical absence of amorphous phase angle is ode and of a carbon onion structure and thirdly, the size of the diamond core is not changed, i.e. the diamond phase is not oxidized.
The examples demonstrate that the most significant transformation of the non-diamond phase of carbon is observed when processing the mixture in SLE containing the decomposition products of hydrogen peroxide. Found that when processing the detonation of carbon in supercritical aqueous solvents, oxidation of the diamond core.
As can be seen from the text and examples, the invention solves the problem of surface modification of nanoparticles condensed carbon phase containing ultrafine diamonds, removal and decomposition of non-diamond structures, creation of environmentally friendly waste-free technology.
1. The processing method of detonation of carbon, characterized in that the processing is carried out in supercritical water.
2. The processing method of detonation of carbon, characterized in that the processing is carried out in supercritical water with the addition of hydrogen peroxide.
SUBSTANCE: invention relates to the technology of minerals, particularly to the technology of producing synthetic diamonds. The said method involves covering a diamond monocrystal with an oil film and irradiation with a millisecond ruby laser with energy density 35 to 40 J/cm2 and pulse duration of 0.5 ms.
EFFECT: invention allows for obtaining synthetic diamonds from oil material.
3 ex, 2 dwg
SUBSTANCE: method includes stagewise diamonds treatment in autoclave at increased temperature and pressure under the action of microwave radiation: in the first stage -with mixture of nitric acid and hydrogen peroxide, in the second stage- with mixture of concentrated nitric, chlorhydric and hydrofluoric acids. The treatment in both stages is carried out in acids gas phase at autoclave filling 45-55%, in the first stage the volume ratio nitric acid/hydrogen peroxide is 4:1 respectively, the treatment is carried out at temperature 215-250°C during 15-60 min. In the second stage the volume ratio nitric acid/chlorhydric acid/hydrofluoric acid is 5:4:1 respectively; the treatment is carried out at the same temperature during 15-150 min. In the third stage the mixture is treated with 5% solution of chlorhydric acid/ during 5-15 min and temperature not more than 160°C.
EFFECT: efficiency enhancing of diamonds purification process along with increase of the used equipment productivity and decrease of reagents consumption.
SUBSTANCE: invention can be used for preparation of detonation nanodiamonds suspension with positively charged particles. The nanodiamonds powder is dispersed with ultrasound in the saturated solution of polyvalent metals salts, the obtained mixture undergoes the thermal treatment up to drying, heated at 380-520 K during 30 min and washed with water up to ion absence in the wash water.
EFFECT: obtaining of the nanodiamonds with positively charged particles in the water suspensions at low process time and decrease of reagents toxicity.
SUBSTANCE: invention can be used at production of finishing compositions, film coatings, radiation-resistant materials. The diamond-carbon material contains the carbon in the form of diamond cubic modification and the X-ray amorphous phase in the mass ratio (40-80):(60-20) respectively; the content of said material is as follows (wt %): carbon 89.1-95.2; hydrogen 1.2-5.0; nitrogen 2.1-4.8; oxygen 0.1-4.7; non-combustible admixtures 1.4-4.8. This material is obtained in enclosed volume, in the gas phase inert to carbon by the detonation of carbon-containing explosive with oxygen deficiency placed into the shell of deoxidant-containing condensed phase with deoxidant/carbon-containing explosive mass ratio not less than 0.01:1. The samples of the obtained diamond-carbon material are prepared for elemental analysis by exposition at 120-140°C under vacuum 0.01-10.0 Pa during 3-5 hrs and following treatment at 1050-1200°C by the oxygen flow with the rate providing their combustion during 40-50 s.
EFFECT: invention allows to obtain the product with high carbon content, predictable properties and ultimate composition in the desired phase state.
4 cl, 1 tbl, 25 ex
SUBSTANCE: present invention relates to chemical engineering, and to high-pressure technology of making diamonds, particularly for growing large crystals, the process of which is long. The high-pressure apparatus has a multiple-punch unit, which is enclosed in a sealed elastic casing 6. In the first version the multiple-punch unit is fitted on a sealed hollow platform 1, which has at least two sealed cavities 10, at least one of which is linked through a valve with the external environment for filling with water when submerged. In the second cavity there is a motor 11, with a pump for pumping water from the first sealed cavity when raising the apparatus. In the second version the sealed cavities can be made in the sealed hollow platform and in one of the punches. In the third version the sealed cavities can be made in at least two punches of the multiple-punch unit.
EFFECT: no use of load-carrying structures and compressors in the apparatus due to the possibility of using natural water column pressure, created by the Earth gravitational field.
15 cl, 2 dwg
SUBSTANCE: carbon-containing explosive with negative oxygen balance is placed in a shell of condensed phase including reduction agent. Mass ratio of reduction agent to carbon-containing explosive is not less than 0.01:1. Detonation is performed in closed volume in gas medium inert to carbon. Detonation product is processed by 2-40% aqueous nitric acid together with oxygen of compressed air at 200-280°C and pressure of 5-15 MPa. Obtained nanodiamond includes carbon of cubic diamond modification and roentgen-amorphous phase at the ratio of (82-95):(18-5) wt % respectively. Element composition of nanodiamond, wt %: carbon 90.2-98.0; hydrogen 0.1-5.0; nitrogen 1.5-3.0; oxygen 0.1-4.5.
EFFECT: improved process safety, obtaining nanodiamond with predictable properties at industrial scale.
3 cl, 5 tbl
SUBSTANCE: present invention can be used in making a cutting and a machining tool and electrodes. The sintered diamond object with high strength and high wearing resistance contains 80-98 vol.% particles of sintered diamond, with average size of not more than 2 mcm, and a phase of binding substance, containing 50-99.5 wt % cobalt and 0.5-50 wt % of at least one element, chosen from a group comprising Ti, Zr, Hf, V, Nb, Ta, Cr, Mo. Part of the element or weight of the element is in form of carbide particles, with average size of not more than 0.8 mcm. The texture of carbide particles is non-continuous, and adjacent diamond particles are bonded together. Sintering is carried out at 5.7-7.5 GPa pressure and 1400-1900°C temperature in a "belt" type super-high pressure device.
EFFECT: provision of transverse breaking strength of not less than 2,65 GPa, excellent wearing resistance, resistance to shearing, shock resistance and thermal conductivity.
7 cl, 6 tbl, 5 dwg, 6 ex
SUBSTANCE: mixture from source of carbon - graphite and metal-solvent based on nickel-manganese alloy in ratio 40:60 of weight respectively is prepared. 3.73-33.55 wt % of manganese carbide powder Mn7C3 and 2.27-20.45 wt % of nickel powder are introduced into mixture on condition that ratio of nickel and manganese in metal-solvent is preserved. Obtained charge is pressed into tablets, put into alundum crucible and thermally processed in vacuum.
EFFECT: increase of diamond crystals output and increase of grainularity part without using expensive inoculating diamond crystals.
FIELD: chemistry, technological processes.
SUBSTANCE: invention allows to obtain memorial diamond from pale-yellow to light-blue tint depending on content of admixture in it, which is identified with exact person and is an object, which reminds of him/her. Method includes processing of biological material belonging to exact individual, and growing on its basis artificial diamond by acting on it with high pressures and temperatures. Processing is performed by mechanical grinding, preliminary drying, chemical processing in hydrochloric acid, chemical processing with complex-former Trilon-B, chemical processing with mixture of mineral acids - hydrofluoric and nitric or sulfuric acids, repeated washing after each chemical processing with said reagents to neutral reaction, filtration and drying until pure highly-dispersive carbon of biological origin is obtained.
EFFECT: obtaining carbon of high purity with characteristic microelements for exact individual.
6 cl, 3 tbl
FIELD: technological processes.
SUBSTANCE: initial substance 2 is heated by exothermal reaction of termite mixture 3 combustion, which contains catalyst, exposed to shock pressure created with blasting charge 5, and cooled on separate metal surface, which is made in the form of tube 1. Blasting charge 5 is installed around tube 1. Initial substance 2 is used in the form of geometric reflection of tubular cavity, and thermite mixture 3 is placed around it. Impact of shock pressure is carried out after heating of initial substance, its displacement into tubular cavity and its filling.
EFFECT: increase of diamonds output and reduction of power inputs and blasting charge consumption.
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.
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