RU2384524C2 - Method of preparing stable suspension of detonation nanodiamonds - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: suspension of detonation nanodiamonds (DND) is obtained through detonation of carbon-containing explosive substance or a mixture of explosive substances with oxygen deficiency in an enclosed volume in a non-oxidising medium with subsequent chemical cleaning of nanodiamonds in an oxidising medium containing nitrate- and/or nitrite-ions, and washing with water. After chemical cleaning, the water suspension of detonation nanodiamonds with pH 2.6-6.9 is treated with ammonia until achieving pH 7.1-12, heated to 150-200°C for 1.0-120 minutes to form colloidal particles of detonation nanodiamonds in the water, 50-80% of which have size of 10-100 nm, and the nanodiamonds have specific surface area of 450-500 m²/g.

EFFECT: invention enables production of diamond-containing material with high stability of DND particles without their aggregation in the suspension for a long period of time.

3 cl, 2 ex, 1 tbl

Description

Technical field

The present invention relates to the field of inorganic chemistry of carbon, more specifically to a process for producing a stable suspension of cubic (diamond) carbon modification formed by detonation synthesis — detonation nanodiamonds (DND), which can be used in electroplating; chemical precipitation of metals; in the preparation of polishing systems; in polymer chemistry; upon receipt of magnetic information carriers; in the manufacture of cutting and abrasive tools; in plasma chemistry; as a catalyst in the synthesis of any diamonds, in heterogeneous and electrochemical catalysis; as a hydrogen accumulator; for the manufacture of semiconductor diamonds; for the manufacture of highly active adsorbents; for the manufacture of biologically active compositions and in biochemical synthesis; for the preparation of colloidal suspensions of DND in non-aqueous media; for the preparation of additives for oils, lubricants and cutting fluids.

State of the art

The properties of diamond-containing materials obtained using the energy of the explosion, and when undermining also in the conditions of their synthesis and separation from impurities, are known in the industry.

The properties of diamond obtained from chemically bonded "excess" carbon explosives are described by K.V. Volkov and his co-authors [2]. The synthesis is carried out in an explosive chamber in an atmosphere of carbon dioxide and in an aqueous shell. The particle size of the obtained diamond is from 4 to 6 nm, the shape of the particles is round. The pycnometric density is 3.2 g / cm ³ . The product in the air contains 90% diamond and adsorbed gases to balance. The product begins to oxidize at 623 K.

To isolate the final diamond product, a set of chemical operations is used to either dissolve or gasify the impurities present in this material. Admixtures, as a rule, are of two types: non-carbon (metal, oxides, salts, etc.) and non-diamond forms of carbon (graphite, soot, amorphous carbon).

A diamond-containing material [4] is described having the following elemental composition in a percentage by weight: carbon 75-90, hydrogen 0.6-1.5, nitrogen 1.0-4.5, oxygen - the rest, the next phase composition in mass percent : X-ray amorphous diamond-like phase 10-30, diamond cubic modification - the rest, and having a porous structure. 10-20% of the surface of the material consists of methyl, nitrile and hydroxyl groups and 1-2% of the surface consists of carbon atoms with uncompensated bonds. The method of obtaining this material consists in detonation of a carbon-containing explosive with a negative oxygen balance or a mixture of explosives in a closed volume in an atmosphere of gases inert to carbon with an oxygen content of 0.1-6.0% by volume, at a temperature of 303-363 K and in the presence of ultrafine carbon phase with a concentration of 0.01-0.15 kg / m However, all the features claimed in this patent are widely known from literary sources. So, p. 1 .:

1.1. Elemental composition, wt.%:

carbon from 75 to 90 hydrogen from 0.8 to 1.5 nitrogen from 0.6 to 4.5 oxygen the rest is up to balance

(known from [5-7]).

1.2. Phase composition, wt.%:

amorphous carbon from 10 to 30 diamond with a cubic diamond structure the rest is up to balance

(described in [5, 8]).

1.3. The porous structure of the inventive material having pores with a pore volume ranging from 0.6 to 1.0 cm ³ / t (described in [5, 9, 10]).

1.4. On 10-20% of the surface of the material there are methyl, nitrile, primary and secondary nitro groups (known from [5-7, 10, 11]); 1-2% of the surface of the material is occupied by carbon atoms with uncompensated bonds (described in [12]).

1.5. The specific surface is in the range from 200 to 450 m ² / g (described in [5, 10]).

p. 2 .: synthetic diamond-containing material according to claim 1., in which the pore diameter in the range from 7.5 to 12.5 nm (described in [9]).

p. 3 .: synthetic diamond-containing material according to claim 1, in which the constant (parameter) of the crystal lattice is 0.03562 ± 0.0004 nm (described in [5, 14, 15]).

item 4. and claim 5: a diamond-containing material obtained in a process consisting essentially of blasting in a closed volume of charge (described in [1-19]), consisting essentially of a carbon-containing explosive or mixture of explosives (described in [1-19 ]) having a negative oxygen balance (described in [1-19]), and charge detonation in the presence of carbon particles at a concentration of from about 0.01 to 0.15 kg / m ³ (the usual consequence of periodically repeated explosive detonation in a closed volume - the smallest particles of the carbon phase are constantly in suspension i) in an environment containing essentially from 0.1 to 6 vol.% oxygen (the usual technique of “burning” air oxygen, with which an explosive chamber is filled before detonation, the indicated amount of oxygen really has little effect on the DND output - it has been studied and described in great detail) in [20]) and to the balance of gases inert to carbon at temperatures from 303 to 363 K (described in [14, 21, 22]).

p. 6 .: the process of preparing a synthetic diamond-containing material, consisting essentially of:

a) filling a pressure vessel with a charge consisting essentially of at least one carbon-containing solid explosive or a mixture of carbon-containing solid explosives, said charge having a negative oxygen balance, and a medium consisting essentially of gases and ultrafine particles of carbon in the form of a suspension in gases, and concentrations from 0.01 to 0.15 kg / m ³ , these gases, consisting essentially of oxygen in an amount of from 0.1 to 6 vol.% and to the balance of nitrogen or gases inert to carbon (described in [ 1-22]).

b) closed pressure vessels and charge detonation occurring at a temperature of 303 to 363 K in the absence of carbon material (without loading (additive) carbon material), excluding carbon-containing explosives or explosive mixtures in order to form a synthetic diamond-containing material from products decomposition of explosives or mixtures of explosives and not get carbon particles in the medium (the usual technique for the first explosion in a gaseous environment [1-22] or explosion in water [23, 24], or in ice).

c) extraction of synthetic diamond-containing material (various methods are described in many sources [6, 9, 10].

Clause 7 .: the process claimed in Clause 6, in which the explosive or explosives are selected from the group consisting of HMX, Trinitrotriaminobenzene, RDX, and a mixture of RDX and TNT (all these explosives and their mixtures have been extensively and thoroughly investigated and described in [1-24], especially in [14, 15, 17].

Thus, all the features of the invention set forth in the patent [4] are widely known and described both separately and together long before the filing of the materials described in the patent [4].

At the same time, diamond - containing material described in the patent [4], is a conventional ultrafine detonation synthesis diamonds obtained by the standard method.

The authors cite data that their purified DNDs can have up to 5% ash (fireproof residue) and, in their opinion, this does not interfere with the use of diamonds in various applications. However, this is not so, for processes such as electrochemical gilding, silvering and plating, the presence of a large number of inorganic impurities is undesirable. It is highly undesirable to use such DNDs in finishing and superfinishing operations, for modifying a magnetic recording layer, in plasma deposition of a metal diamond coating, as catalysts, for the production of materials for semiconductor technology, in medicine and biology, etc.

For such complex hierarchical structures, the purity of the product in the usual sense (quantity and types of impurities) is, of course, an important factor for the further use of such a product, but only in very simple technologies. For many processes, not only the formal cleanliness of DNDs is important, but also the state of aggregation, the amount and ratio of surface functional groups of DNDs are determined not only by the synthesis conditions, but, to a certain extent, by the chosen option of chemical cleaning and subsequent modification of the surface of DND particles.

Moreover, the production process itself, described in sufficient detail in [4], is quite simple, the following operations are most complicated. The low quality of DND according to this patent is determined, first of all, by ineffective chemical cleaning - boiling the diamond charge in hydrochloric acid and subsequent two-hour heating at 250 ° C in a mixture of concentrated nitric and sulfuric acids.

Despite the abundance of work on diamond-containing materials synthesized using the energy of decomposition of explosives, as well as the special processes for obtaining these materials, they cannot reveal technical solutions to problems that could create the basis for an effective, economical, and environmentally friendly technology for the industrial production of stable DND suspensions .

As a prototype, the method of stabilization of aqueous suspensions of detonation nanodiamonds formed by detonation of a carbon-containing explosive or a mixture of explosives with negative oxygen balance in a closed volume in a non-oxidizing medium, followed by chemical purification of nanodiamonds in an oxidizing medium containing nitrate and / or nitrite ions, was chosen , and water washing using dispersants [25]. As dispersants were used surfactants (surfactants) - neonol (alkyl phenol) and potassium pyrophosphate.

The use of dispersants does not improve the stability of detonation nanodiamond particles. The addition of a small amount of neol leads to instant coagulation of the particles of the DND suspension. The addition of potassium pyrophosphate at concentrations from 0.1 to 0.0001% (by mass) does not promote stabilization, but aggregation of DND particles. Currently, there are no stable aqueous suspensions of nanodiamonds. Over time, 1-6 months, aggregation of aggregates and their precipitation occurs.

The problem to which the invention is directed, is to develop a method for stabilizing detonation nanodiamond suspensions, which makes it possible to create a diamond-containing material with increased stability of DND particles without aggregation in suspension for a long time.

Disclosure of the invention.

A method is proposed for producing a stable suspension of detonation nanodiamonds formed by detonation of a carbon-containing explosive or a mixture of explosives with a negative oxygen balance in a closed volume in a non-oxidizing medium, followed by chemical cleaning of the nanodiamonds in an oxidizing medium containing nitrate and / or nitrite ions, and aqueous washing, in which, according to the invention, an aqueous suspension of detonation nanodiamonds with a pH of 2.6-6.9 is treated with ammonia to a pH of 7.1-12, heated to a temperature of 150-200 ° C for 1.0-120 minutes with the formation in water of colloidal particles of detonation nanodiamonds, 50-80% of which has a size of 10-100 nm, and the specific surface area of the nanodiamond is 450-500 m ² .

An analysis of the numerous works [1-24] presented above convincingly proves that the sizes of primary DND crystals of 4–6 nm (narrow-mode distribution in the region of 4.3 nm) are always obtained when there are conditions for obtaining the diamond phase in general. In addition, in fact, the pore volume (0.3-1.0 mm ³ / g), their diameter, crystal shape, crystal lattice parameter, microstress level in a diamond crystal (~ 10 GPa), a combination of a cubic diamond crystal with an amorphous phase , the dielectric properties of the DND surface, surface and internal impurities are practically independent of the method of obtaining UDD and vary in a rather narrow range (unlike the claims in the patent [4]. But the type, number of functional groups, their ratio, size of primary aggregates and the subsequent their organization in general - surface condition beam, greatly depend on the method of chemical cleaning and subsequent operations Essentially these operations and determining a particular quality of the purified DNA, or the degree of their suitability opposite -. unsuitability for various applications.

So, during purification in the medium of perchloric and hydrochloric acids, various chlorine derivatives appear, including chloride ion on the surface of the DND; when processing chromium mixtures in sulfuric acid - chromium-containing groups, sulfates, sulfites and sulfo groups; when processing oleum-nitrogen mixtures - nitrate, nitrite and nitro groups, sulfo groups of various nature; when treated with hydrogen peroxide and ozone - a large number of oxygen-containing groups; and when treated with nitric acid - nitrate, nitrite and nitro groups. In addition, due to the strong adsorption effect in the complex structure of DND aggregates, acid residues of the liquid-phase oxidizing agent are retained. However, functional groups grafted onto the surface and adsorption-retained acid residues can interfere with the use of DND in a number of processes: in some processes of gilding, plating, silvering, etc., in some finishing polishing processes, in medical and biological practice, etc.

The most advanced, technologically advanced and environmentally friendly is a method for cleaning DND from impurities using dilute nitric acid at high temperature (up to 280 ° C) and pressure (up to 100 atm) [26]. Such a reaction suspension of AS in dilute nitric acid is homogeneous, colloid-stable, highly dispersed and low viscosity. During the reaction, the oxidizer is freely accessible to solid particles and the diffusion restrictions on the process rate are practically removed. The purity of DND after such a process can reach 99.5%.

It is extremely urgent to get rid of both the excess acidity of DND and the presence of undesirable functional groups.

In addition, an obstacle to the effective use of DND is the relatively high aggregation of these diamonds: in the dry state (generally accepted for DND consumers), aggregates reach 2000-3000 μm, in the best known suspensions (without intermediate isolation of DND in the form of a dry powder) ~ 350-500 nm

T.O. Two major problems were solved as follows: when treating the AS with any oxidizing medium containing nitric acid or nitrogen oxides, as already noted, the surface of the DND is saturated with nitrate, nitrite, and nitro groups; acid nitrogen-containing residues and nitrogen oxides remain adsorbed to the pore surface of the DND aggregates .

After high-temperature treatment, DNDs are repeatedly washed with water, however, adsorption-bound acid groups always remain in DND. Even when cleaning the most easily removed nitric acid, after 5-6 washes of stably bound nitric (and nitrous) acid in the DND, 0.3-0.4 wt.% Of the weight of the DND remains.

If such an amount of gaseous or liquid (in water or in a liquefied form) ammonia is added to an aqueous DND suspension with a pH from 2.6 to 6.9, so that, after equilibration, the pH of the resulting suspension is in the range from 7.1 to 12, then all . acid residues will be bound into readily soluble, easily removable ammonia salts.

And in the case of purification of ASh with only nitric acid or nitrogen oxides, there will be only ammonium nitrate and ammonium nitrite.

When such a suspension is heated at a temperature from 150 to 200 ° С, the salts of nitric and nitrous acids begin to decompose violently with the release of water and gaseous products by reactions (1) and (2), nitrous oxide by reaction (3), and nitrogen oxides by reaction ( 4) being in contact with excess ammonia, due to chemical reactions turn into nitrogen and water:

DND in these processes also acts as a catalyst for the decomposition of ammonium and its salts, shifting these reactions toward lower temperatures. So, the reaction of intensive decomposition of NH ₄ NO ₃ does not begin at 170 ° C (under ordinary conditions), but already at 150 ° C; the decomposition reaction of NH ₄ NO ₂ also begins at 50 ° C, and not at 70 ° C. The decomposition of salts, surface nitro groups in the presence of ammonia is essentially a chain process. As a result of rapid and rapid gas evolution, destruction (rupture) of UDD aggregates with a size of 350-500 nm into aggregates from 10 to 100 nm occurs - such aggregates in an aqueous suspension are from 50 to 80% in quantity. Moreover, all products are harmless gases (nitrogen and excess ammonia) or water.

The specific area of such DNDs is naturally 1-2 orders of magnitude larger than the specific area of the previous suspension. However, the generally accepted measurement technique, determined by the Brunauer-Emmet-Teller (BET) isotherms of thermal desorption of nitrogen or argon, suggests the presence of DND in the form of a powder. And UDD in the form of powder always agglomerates, but even in this case, the specific area of the obtained diamonds is in the range from 450 to 550 m ² / g.

After cooling the DND suspension and its 1-2 water washes, a very stable colloidal stable aqueous DND suspension is obtained (DND sediment does not precipitate for 24 months), which greatly expands the range of its use in all possible processes.

It is not advisable to use a DND suspension with a pH of less than 2.6 to neutralize ammonia after chemical purification due to the large consumption of ammonia to neutralize acids and the longer exposure time at high temperatures to decompose these salts. At the same time, to achieve the most complete washing of the UDD from the acid (without fail to achieve a pH of ~ 7) is also impractical due to the high time spent on this process.

Neutralization with ammonia should ensure the creation of an alkaline medium in suspension, guaranteeing a small excess of ammonia, i.e. pH 7.1-12, so that excess ammonia, on the one hand, supports the irreversibility of reactions (1), (2) and (4), and on the other hand, it would be enough to react with acid residues and acid gases located in the deep pores of DNDs, access to which is due to increased diffusion at high temperatures (150-200 ° C) and, especially, when gases are destroyed by DND aggregates.

Creating a pH of more than 12 with the introduction of ammonia (in gaseous form, in the form of a solution in water or in a liquefied form) is not advisable due to excessive consumption of ammonia and the development of high pressures during the process.

Typically, the pressure during the process is 10-15% higher than the pressure of water vapor at the appropriate temperature.

Intensively, the decomposition of ammonia salts and the reaction of nitrogen oxides with ammonia begin under our conditions at 150 ° C. It is not advisable to maintain a temperature above 200 ° C due to the increase in pressure in the equipment and, therefore, increased requirements for the equipment.

If at 200 ° C the process of salt decomposition and the reaction of ammonia with residual nitrogen oxides is already completed within 1 min, then at 150 ° C, a time of 120 min is required to guarantee the completion of all processes. When the time decreases below 1 min at 200 ° С, all the reactions (1) - (4) we need do not have time to complete, and an increase in time in excess of 120 min at 150 ° С is not advisable for economic reasons.

For a better understanding of the present invention according to claim 1, specific examples are provided.

Example 1. Illustrates the typical course of the process of ammonia thermolysis of DND in periodic conditions.

In a 400 ml titanium autoclave equipped with a pressure sensor (DT), a thermocouple, and a gas bleed system, 300 ml of an 8% aqueous DND suspension with a pH of 8.0, obtained by pre-neutralizing 300 ml of an 8% aqueous acid DND suspension ( chemical cleaning phase - nitric acid) with a pH of 2.6 gaseous ammonia. After sealing, the autoclave is placed in a bath with a Rose alloy, and the temperature of the contents of the autoclave is raised to 200 ° C and held for 5 minutes. The pressure in the autoclave at the end of the exposure is 38 atm. After exposure, the autoclave is cooled to 20-30 ° C, the excess gas pressure is vented. Obtaining DND in the form of an aqueous suspension is washed 2 times with water, lowering the pH of the medium to 7.1. The resulting suspension is stable in time (no precipitate of aggregated DND appears) for at least 24 months. Prior to the treatment with ammonia at high temperature and pressure, the content of non-combustible impurities in the DND was 0.95 wt.%, And after ammonia heat treatment it was 0.37 wt.%, 72% of diamonds are 10 to 100 nm in size, and the specific surface of the DND dry powder ( BET method) 515 ± 10 nm.

Example 2. Illustrates the typical course of the process of ammonia thermolysis of DND and the continuous implementation of the method.

An aqueous 9% suspension with a pH of 3, obtained after chemical cleaning of a diamond-containing mixture and partial washing with water, is neutralized with an aqueous 25% ammonia solution to a pH of 7.2. Then, this suspension is pumped through a ND-2.5 / 400 metering pump through a one-liter tubular displacement reactor at a rate of 1 l / h, providing a one-hour stay of the reaction mixture in the operating temperature zone. Pressure is maintained at 35 atm. After a four-liter titanium collector, the reaction mass is throttled into an open container, from where a suspension of HA with a pH of 7.05 is taken to the wiping stage. Twice wiping with water from salts leads to the coating of a colloidal-resistant suspension for 30 months. Prior to ammonia thermolysis, the content of non-combustible impurities in the DND was 0.7 wt.%, And after processing with ammonia according to the image, the content of non-combustible impurities dropped to 0.23 wt.% 61% of diamonds were from 10 to 100 nm in size, the specific surface area of the dry powder was 490 ± 10 nm.

Other examples are given in the table.

The diamond-containing material obtained by the proposed method has a set of properties that allow it to be included in various composite materials and coatings. The method is characterized by safety, reliability, improved technical, economic and environmental parameters and allows you to organize large-scale production of stable diamond-containing material.

Information sources

1) Adadurov, G.A. et al. "Diamonds Obtained ...," The Physics of Pulse Pressures Proceedings, Research Institute of Physical and Radio Engineering Measurements, Moscow, 1979, p. 157-161.

2) Volkov K.V., Danilenko V.V., Edin V.P. Synthesis of diamond from carbon of detonation products of explosives, FGV, 1990, t.26, No. 3, p.123-125.

3) British patent 1154633, publ. 1969.

4) US Patent 5861349, publ. 1999.

5) A.L. Vereshchagin, V.F. Komarov, V.M.Mastikhin, V.V. Novoselov, L.A. Petrova, I.I. Zolotukhina, N.V. Bychin, K.S. Baraboshkin, E.A. Petrov. "Study of the properties of the diamond phase of detonation synthesis." In the book: Dokl. 5 of the All-Union Conference on Detonation, vol. 1, Krasnoyarsk, 1991, pp. 99-103.

6) T.M. Gubarevich, L.S. Kulagina, I.S. Larionova. "Features of the elemental composition of carbon products of detonation synthesis", ibid., P.130-134.

7) Petrova L.A., Vereshchagin A.L., Novoselov V.V., Brylyakov P.M., Shein N.V. "Investigation of the surface groups of the diamond-like carbon phase." Superhard Materials, 1989, No. 4, p.3-5.

8) Savvakin G.I., Kotko V.A., Ostrovskaya N.F., Kurdyushov A.V. The structure of ultrafine carbon phases formed from carbon-containing compounds under highly nonequilibrium conditions. Powder Metallurgy, 1988, No. 10, p. 78-82.

9) K.S. Baraboshkin, T.M. Gubarevich, V.F. Komarov. "Features of the texture of powders of condensed diamond - containing carbon." Colloid Journal, 1992, vol. 54, No. 6, pp. 9-12.

10) RF patent. No. 2046094, IPC СВВ 31/04, publ. 1995.10.20.

11) T.M. Gubarevich, N.M. Kostyukova, P.P. Sataev, L.V. Fomina. "Study of the microimpurity composition of ultrafine diamonds." Superhard Materials, 1991, No. 5, pp. 30-34.

12) L.A. Petrova, V.V. Novoselov, P.M. Brylyakov and others. "Study of the chemical composition of the surface of ultrafine diamond detonation synthesis." On Sat doc. 9th All-Union Symposium on Combustion and Explosion, Suzdal (USSR), 1989, pp. 14-18.

13) A.V. Ananyin, O.N. Breusov, V.N. Drobyshev, G.E. Ivangikhin, A.I. Shunina. "Thermographic and radiographic studies of the properties of diamonds, synthesis." Superhard Materials, 1986, No. 5, C.11-14,

14) Lyamkin A.I., Petrov E.A., Ershov A.P. et al. Obtaining diamonds from explosives, DAN SSSR, 1988, vol. 302, No. 3, pp. 611-613.

15) Titov V.M., Anisichkin V.M., Malkov I.Yu. Investigation of the synthesis of ultrafine diamond in detonation baths. Physics of Combustion and Explosion, 1989, No. 3, pp. 117-126.

16) V.F. Anisichkin. "On the features of shock-wave decomposition and synthesis of diamond from aromatic compounds." In the book. Report 5 of the All-Union Conference on Detonation, vol. 1, Krasnoyarsk, 1991, p.20-26.

17) V.F. Anisichkin, I.Yu. Malkov, F.A. Sagdeev. "Synthesis of diamond in the detonation of aromatic nitro compounds", ibid., Pp. 27-30.

18) N.V. Kozyrev, G.V.Sakovich, Saint Chel Su, M.S. Stein. "Study of the synthesis of ultrafine diamonds by the method of labeled atoms", ibid., P.176-179.

19) A.Yu. Babushkin, A.I. Lyamkin, A.M. Staver. "The effect of gases on the yield of condensed detonation products of carbon-containing explosives," ibid., Pp. 84-87.

20) I.G. Kuzmin, A.I. Lyamkin, A.M. Staver. "An experimental study of the composition of gaseous detonation products of condensed explosives in various atmospheres." In the book: "Ultrafine materials, preparation and properties", Interuniversity collection, Krasnoyarsk, 1990, pp. 23-28

21) L.I. Akimova, S.A. Gubin, V.D. Odintsov, V.I. Pilekin. "Detonation of explosives with the formation of diamond." In: Dokl. 5 All-Union meeting on detonation, Krasnoyarsk, 1991, v.1, p.14-19.

22) Babushkin A.Yu., Lyamkin A.I., Staver A.M. "Features of obtaining ultrafine carbon-based material from explosives," ibid., Pp. 81-83.

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25) L.V. Agibalova, A.P. Voznyakovsky, V.Yu. Dolmatov, V.V. Klyubin. “The structure of suspensions of ultrafine explosive synthesis diamonds (nanodiamonds). - Superhard materials, 1998, No. 4. S.87-95 - prototype.

26) RF patent №2109683, IPC СВВ 31/06, publ. 1998.04.27.

Claims (3)

1. A method of obtaining a stable suspension of detonation nanodiamonds formed by detonation of a carbon-containing explosive or a mixture of explosives with a negative oxygen balance in a closed volume in a non-oxidizing medium, followed by chemical cleaning of the nanodiamonds in an oxidizing medium containing nitrate and / or nitrite ions, and aqueous washing, characterized in that after chemical cleaning, an aqueous suspension of detonation nanodiamonds with a pH of 2.6-6.9 is treated with ammonia to a pH of 7.1-12, heated to a temperature of 150-200 ° C During 1,0-120 min in water to form colloidal particles detonation nanodiamonds, 50-80% of which has the size of 10-100 nm with a specific surface area of nanodiamonds 450-500 m ² / g. 2. The method according to claim 1, characterized in that gaseous ammonia is used. 3. The method according to claim 1, characterized in that use a solution of aqueous ammonia.