Composition, based on zirconium oxide, titanium oxide or mixed zirconium and titanium oxide, applied on silicon oxide carrier, methods of obtaining thereof, applying thereof and applying thereof as catalyst

FIELD: chemistry.

SUBSTANCE: group of inventions can be used in the production of catalysts, in particular, for the selective NOx reduction. A catalytic composition contains at least one oxide on a carrier, consisting of zirconium oxide, or titanium oxide, or mixed zirconium and titanium oxide, or of zirconium oxide and an oxide of at least one oxide of other element, selected from praseodymium, lanthanum, neodymium and yttrium, applied on a silicon oxide-based carrier. After burning at 900C for 4 hours the oxide on the carrier has a shape of particles applied on the carrier. The size of the said particles constitutes not more than 5 nm, if the oxide on the carrier is obtained on the basis of zirconium oxide, not more than 10 nm, if the oxide on the carrier is obtained on the basis of titanium oxide, and not more than 8 nm, if the oxide on the carrier is obtained on the basis of mixed zirconium and titanium oxide. After burning at 1000C for 4 hours the size of the particles constitutes not more than 7 nm, if the oxide on the carrier is obtained on the basis of zirconium oxide, not more than 19 nm, if the oxide on the carrier is obtained on the basis of titanium oxide, and not more than 10 nm, if the oxide on the carrier is obtained on the basis of mixed zirconium and titanium oxide.

EFFECT: invention makes it possible to reduce the size of the particles in the catalytic composition, their aggregation and sintering at high temperature.

10 cl, 1 tbl, 9 ex

 

The present group of inventions relates to a composition based on zirconium oxide, titanium oxide or a mixed oxide of zirconium and titanium supported on a carrier of silica, the means of its production and its use as a catalyst.

Catalysts often consist of an active phase which is a phase with desired catalytic properties, and the media, which caused the aforementioned active phase. For catalyst efficiency is important that the active phase was more finely dispersed on the carrier, so that this active phase was on a carrier in the form of finely dispersed, not subjected to aggregation of particles. In addition, since the catalysts are often exposed to high temperatures, it is also necessary to finely dispersed state of the active phase was preserved even at this temperature. In other words, should not occur sintering of particles.

The aim of the present invention is to develop catalysts that meet these requirements.

For such purpose, the composition according to the invention in accordance with the first embodiment contains at least one oxide on the carrier obtained on the basis of zirconium oxide, titanium oxide or a mixed oxide of zirconium and titanium supported on a carrier of ethoxide silicon, and is characterized by the fact that after firing at 900C for 4 hours, the oxide on the carrier is in the form of particles deposited on said media, which are:

not more than 5 nm, if the oxide on the carrier obtained on the basis of zirconium oxide;

not more than 10 nm, if the oxide on the carrier obtained on the basis of titanium oxide;

not more than 8 nm, if the oxide on the carrier obtained on the basis of a mixed oxide of zirconium and titanium.

According to the second variant implementation, the composition contains at least the following components: the same type of oxide on the media, the same media type, and differs in that after firing at 1000C for 4 hours, the oxide on the carrier is in the form of particles deposited on said media, which are:

not more than 7 nm, if the oxide on the carrier obtained on the basis of zirconium oxide;

not more than 19 nm, if the oxide on the carrier obtained on the basis of titanium oxide;

not more than 10 nm, if the oxide on the carrier obtained on the basis of a mixed oxide of zirconium and titanium.

Other distinctive features, details and advantages of the present invention become more deeply understood upon reading the following further description and specific examples are intended for illustration only and are not restrictive.

Under rare earth element understand the elements from the group consisting the th of yttrium and elements of the periodic system, with atomic number lying in the range from 57 to 71 inclusive.

In continuation of the present description under understand specific surface the specific surface according to BET, defined by nitrogen adsorption in accordance with ASTM D 3663-78 established on the basis of the method of brunauer, Emmett and teller described in The Journal of the American Chemical Society, 60, 309 (1938).

In addition, calcination at a given temperature for a specified time, unless the opposite, firing in the air after establishing a constant temperature within the indicated time.

The composition according to the invention contains an oxide on a substrate in the form of particles of nanometric size, the mentioned particles supported on a carrier. Thus, the oxide particles on the media are mostly located on the surface of said carrier, thus assume that the particles can be inside the pores of the support, however, remain on the surface.

This oxide on the substrate, first and foremost, can be a zirconium oxide without additives, i.e. a simple oxide in the form of ZrO2.

The oxide on the substrate may also be a doped zirconium oxide, i.e. it can be obtained on the basis of zirconium oxide and at least one oxide of another element M selected from among the praseodymium is, lanthanum, neodymium and yttrium. In this case, the zirconium oxide ZrO2is a major or dominant component, whereas the element or elements M is the rest of oxide on the carrier.

The content of the element M is not more than 50 wt.%, moreover, the zirconium oxide is at least 50 wt.% oxide on the carrier. This value content, expressed as weight of oxide of the element M or set of elements of M with respect to the weight of the entire oxide on the carrier (zirconium oxide and oxide(s) item(s) M). The value of the content of the element M may vary in a wide interval, in particular it may be in the range from 5 to 40%, more preferably from 10% to 40%. This value is particularly preferably may lie in the range from 10% to 30%.

The oxide on the carrier can also be a titanium oxide TiO2.

In addition, the oxide on the carrier may be a mixed oxide of zirconium and titanium. The mixed oxide in this case it is necessary to understand the solid solution of oxides of titanium and zirconium in the form of pure crystallographic phase with the structure ZrTiO4. In this case, the analysis of the product using the method of x-ray diffraction (RD) does not allow to establish the existence of different patterns, in addition to ZrTiO4. This structure corresponds to the card 34-415 joint Committee on standards there powder diffraction (JCPDS). Such solid solution is generally in a state in which the proportion of titanium oxide relative to the total weight of the mixed oxide may be in the range from 30 wt.% up to 40 wt.%.

Here it should be noted that the composition may contain several types of oxides on the carrier, i.e. to simultaneously contain particles of zirconium oxide, particles of titanium oxide and particles of mixed oxide.

The oxide on the carrier is in crystalline form.

The oxide on the carrier is in the composition according to the invention in the form of particles of nanometric size.

It should be noted that the oxide particles on the carrier can either be solid or may be in the form of units.

The values of the dimensions given in this description represent the average values of the dimensions specified way RD. The value measured by the method of EP corresponds to the size of the domain of coherence calculated from the width of the three most intense diffraction beams in the spatial group x, y, z using the model of Debye-sherrer.

Above were given the particle size of the oxide on the carrier, depending on the type of oxide on the carrier and calcining the composition. Here it should be noted that the values given for the composition subjected to calcination at 1000C (the second option exercise), can be applied to the composition is, which was previously subjected to an annealing at 900C for 4 hours, which shows that the impact on the composition of the invention increasing the temperature from 900C to 1000C a significant sintering of oxide particles on the media does not occur.

According to preferred variants of implementation of the present invention, the particle size of the oxide on the carrier can be even lower than the sizes listed above. Thus, the compositions are subjected to calcination for 4 hours at 900C, the said amount may be not more than 4 nm, if the oxide on the carrier obtained on the basis of zirconium oxide, possibly doped, and not more than 7 nm, if the oxide on the carrier based on titanium oxide or a mixed oxide of zirconium and titanium. The minimum particle size are not critical and can be very low. Solely as an example, you can specify that the size of the particles may be at least 2 nm, more preferably at least 3 nm, if the oxide on the carrier obtained on the basis of zirconium oxide, possibly doped, and at least 3 nm, more preferably at least 4 nm, if the oxide on the carrier based on titanium oxide or a mixed oxide of zirconium and titanium. These minimum values are also given for the compositions subjected to calcination at 900C for 4 hours

For songs that have been subjected to calcination for 4 hours at 1000C, the said amount may be not more than 6 nm, if the oxide on the carrier obtained on the basis of zirconium oxide, possibly doped, not more than 15 nm, if the oxide on the carrier based on titanium oxide, and not more than 8 nm, if the oxide on the carrier obtained on the basis of a mixed oxide of zirconium and titanium. Purely as an example, you can specify that for compositions subjected to calcination for 4 hours at 1000C, the particle size may be at least 2 nm, more preferably at least 3 nm, if the oxide on the carrier obtained on the basis of zirconium oxide, possibly doped with at least 6 nm, more preferably at least 7 nm, if the oxide on the carrier based on titanium oxide, and at least 5 nm, more preferably at least 6 nm, if the oxide on the carrier obtained in the basis of a mixed oxide of zirconium and titanium.

The last value can be applied to the compositions, also previously subjected to an annealing at 900C for 4 hours.

The content of the oxide on the carrier in the composition according to the invention is usually not more than 50 wt.% on the whole composition (oxide on the media and the media). In particular, it can be no more than 30%.

The minimum content of the oxide on the media is so important, what oterom skilled in the art will know, since it is possible to achieve a sufficient catalytic activity and is determined depending on the desired performance of the composition. Just as an example, we can say that the mentioned minimum value is usually at least 3 wt.%, more preferably at least 4 wt.%.

The oxide content in the media, in particular, may lie in the range from 10% to 50%, more preferably from 10% to 30%.

Media in compositions represents the media on the basis of silicon oxide.

Taking into account the application of the compositions according to the invention in applied catalysis a silicon oxide, suitable for use in the field, preferably silicon oxide, having a high and stable, i.e. keeping a high enough value even after exposure to high temperature, the specific surface. For example, it is possible to use silica having a specific surface area equal to at least 100 m2/g, preferably at least 150 m2/year

Such silicon oxide may be a precipitated or pyrogenic silica. The silicon oxide can be stabilized stabilizing element, such as aluminum.

As examples of oxides of silicon, suitable for use in the present invention, it is possible to result such is, as described in WO 2005/061384 and WO 99/49850.

Finally, it should be stated that the composition of the invention can have a high specific surface area by BET, is able to make after firing at 900C for 4 hours, at least 80 m2/g, more preferably at least 120 m2/g, even more preferably at least 150 m2/g After calcination for 4 hours at 1000C. such compositions may have a specific surface area equal to at least 50 m2/g, more preferably at least 80 m2/g, even more preferably at least 100 m2/year

According to a preferred variant implementation, as the carrier used silicon oxides, previously subjected to firing at a temperature lying in the range from 600C or 650C to 900C, and having a value loss on ignition (SPT)lying in the range from 2% to 15%, more preferably from 2 to 10% (measured until reaching constant weight).

The composition of the invention can be prepared in various ways, which are described next.

A. the First method of preparation of the compositions according to the invention

The first method includes the following steps:

- cast colloidal dispersions of compounds of zirconium and/or titanium, and may compound of the element M in contact with a suspension of the nose is the body;

- spray drying thus obtained mixture;

- firing the dried product obtained in this way.

Thus, the first step of this method consists in obtaining a mixture of a colloidal dispersion of zirconium compounds, colloidal dispersion of titanium compounds or colloidal dispersion containing a compound of zirconium, and a compound of titanium, depending on the nature of the oxide on the carrier in the composition that you want to cook. In the case of the preparation of compositions in which the oxide on the carrier is a mixture of zirconium oxide and at least one oxide of another element M, the mixture also contains a colloidal dispersion of the oxide of this element. You can also use one of the colloidal dispersion, the basis of colloids in which is a mixed oxide of zirconium and of an element M of Course, this description applies to the case where the oxide on the carrier contains several elements of M; in this case, it is clear that this can be applied several dispersions of the various elements of M, or perhaps only one colloidal dispersion containing all of the elements of M. For brevity, in the remainder of this description reference will be made to only one dispersion of one element M, however, the present description should be understood as applicable to the above case.

p> Under the colloidal dispersion understand any system that consists of finely dispersed solid particles of colloidal dimensions, i.e. dimensions lying in the range from approximately 1 nm to approximately 100 nm (the size measured by the method of quasielastic light scattering), on the basis of zirconium compounds, titanium and/or of the element M, and a similar connection is typically an oxide and/or hydroxide, in the form of a stable suspension in an aqueous liquid phase, and the particles, in addition, it is possible, can also contain residual amounts associated with or adsorbed ions, including, for example, nitrate-, the acetate, chloride ions or ammonium ions. It should be noted that in such a colloidal dispersion of zirconium, titanium or element M can either be entirely in the form of colloids or simultaneously in the form of ions and in the form of colloids.

The mixture obtained from the above-mentioned dispersion and suspension media. In particular, you can use colloidal dispersion of silicon oxide. Suspension in General is an aqueous suspension.

The mixture is produced in the aqueous phase, usually water, for example, distilled or permuteran water.

The second step of the method is the step of drying.

Drying is carried out by sputtering.

Under spray drying understand the drying by spraying a mixture of hot and the atmosphere (spray-drying). Spraying can be carried out in any well-known type of spray, such as spray heads type of shower spray or otherwise. It is also possible to implement a so-called turbine nozzles. Information about the various methods of spraying, suitable for use in the present method, it is possible, in particular, be found in the seminal work of masters, entitled "Spray drying" (K. Masters, Spray-drying, 2nd ed., 1976, George Godwin, London).

The temperature at the outlet of the atomizer may lie in the range of, for example, from 80C to 150C.

The last step of the method is the step of firing.

Such firing provides the possibility of increasing the crystallinity of the product on the media; the firing method can also be adjusted and/or selected depending on the temperature further application, intended for the composition according to the invention, while taking into account the fact that the specific surface of the product is lower the higher the applied temperature firing. Such firing is usually carried out in air, but, of course, does not rule out the firing, for example, in an inert gas or in a controlled (oxidizing or reducing) atmosphere.

In practice, the firing temperature is usually limited by the range of values lying between 500C and 800C, preferably between 600C and 700C. the Time obigatory in a known manner; it may change, for example, from 30 minutes to 4 hours, but usually the lower, the higher the temperature.

B. the Second method of preparation of the compositions according to the invention

The composition of the invention can also be prepared by the second method described below.

This method contains the following steps:

- obtaining a liquid mixture containing a salt of zirconium or titanium, and possibly the element M and the suspension media;

- heating the thus obtained mixture to a temperature equal to at least 100C;

the extract thus obtained precipitate;

- firing is referred to sludge.

In the first stage, as in the previous method, apply the suspension media, but it is mixed with the salt of zirconium and/or titanium salt and, in the case of compositions in which the oxide on the carrier obtained on the basis of zirconium oxide and an oxide of another element M, with a salt of the element M, the Mixing is carried out in aqueous phase, usually in water. The original suspension of silicon oxide may be acidified.

Salt preferably represent inorganic salts and can be selected, in particular, among nitrates, sulfates, acetates and chlorides.

Thus, in the examples, in particular, to mention sulfate Zirconia, nitrate Zirconia and chloride Zirconia. You can also use oxychloride or oxysulfate titanium.

Following this the method is a step of heating the thus obtained liquid mixture.

The temperature to which the heated liquid mixture is at least 100C., more preferably at least 130C. It can also be in the range from 100C. to 150C. the heating Operation can be carried out by placing the liquid mixture in a closed shell (closed-type reactor of the autoclave). As an illustration, you can specify that in the above temperature conditions in the aquatic environment pressure in the closed reactor can vary over a range of values from more than 1 bar (105 PA) and 165 bar (1,65 .107 PA), preferably between 5 bar (5.105 PA) and 165 bar (1,65 .107 PA). At temperatures close to 100C, it is also possible implementation of heating in an open reactor.

Heating can be carried out either in air or in an atmosphere of inert gas, preferably nitrogen.

Heating time may vary within wide limits, components, for example, from 1 to 48 hours, preferably from 2 to 24 hours. The temperature rise execute with speed, which is not critical; thus, a given reaction temperature can be achieved by heating the liquid mixture, for example, during the time of 30 minutes to 4 hours, and mentioned only that values are given only as an example.

After the step of heating the extracted solid residue, which may be separated from its containing environment with the use of any classic what about the method of separation of solid and liquid phases, including, for example, filtration, decantation, drying or centrifuging.

The extracted product can then be subjected to the procedures of washing, which in this case is carried out by means of water or perhaps a basic solution such as ammonia solution or an acidic solution such as a solution of nitric acid.

In accordance with the private embodiment of the present invention, the method includes the step of aging.

Mentioned aging usually carried out in a suspension obtained after repeated cultivation of sediment in the water, particularly after washing. Aging is carried out by re-heating of the suspension. The temperature to which heat the suspension is at least 40C., more preferably at least 60C., even more preferably at least 100C. Typically, this temperature is not more than 200C., more preferably not more than 150C. Environment support at a constant temperature for a period of time, usually at least 30 minutes, more preferably at least 1 hour. Aging may be carried out at atmospheric pressure or, possibly, at higher pressure.

The last step of annealing the second method can be carried out in the same way as in the first method, therefore, discussed above, regarding the firing is iminimum and to this occasion.

C. a Third method of preparation of the compositions according to the invention

The composition of the invention can also be prepared by the third method, described next. This method contains the following steps:

- obtaining a liquid mixture containing a suspension of the carrier and at least one salt of zirconium or titanium, and may element M;

- bringing the just-mentioned mixture in contact with the base with the purpose of obtaining a precipitate;

- removing the precipitate, thus obtained;

- firing above the sediment.

The first step of the third method is similar to the first stage of the second method, so the above on this issue is applicable to this case.

The second step consists in obtaining a precipitate from the reaction mixture obtained in the previous step, to the base.

As a basis you can use products like, for example, hydroxides, carbonates or basic carbonates. Mention can be made of hydroxides of alkaline or alkaline earth metals, secondary, tertiary or Quaternary amines. However, amines and ammonia may be preferred for the reason that they reduce the risk of contamination of the cations of the alkaline or alkaline earth metals. You can also mention urea.

Bringing into contact, or the contact may be carried out in a liquid medium in any then the (DKE).

Making contact with the ground is a consequence of the sediment suspended in the liquid reaction medium.

The addition of a base, in particular, is carried out until reaching the pH of the reaction medium, is equal to at least 7.

According to one of embodiments of this method, it may contain additional step consisting in treating the suspension obtained in the previous step, by aging. Aging is carried out by heating the suspension to a temperature component of at least 60C., more preferably at least 80C. This temperature is usually not more than 200C., more preferably not more than 150C. Environment support at a constant temperature for a period of time, usually at least 30 minutes, more preferably at least 1 hour. Aging may be carried out at atmospheric pressure or, possibly, at higher pressure.

The extraction and burning of sludge spend ways, similar to the one described above, in particular, for the second method.

The composition of the invention, such as those described above, or the like obtained by the methods described above have the form of powders, however, they may be molded in order to give them the form of granules, beads, cylinders or honeycombs of various sizes.

The composition of the invention could is t be used as catalysts. Therefore, the present invention also relates to catalytic systems containing compositions according to the invention. Such systems contain coating (primer, wash coat) with catalytic properties derived from such compositions, and a binder is applied onto a substrate type, for example, metal or ceramic monolithic. The coating is obtained by mixing the composition with a binder so as to form a suspension, which can then be applied to the substrate.

Such catalytic systems, in particular the composition according to the invention can find a lot of different ways. They are particularly well adapted to the conditions and, therefore, are applicable for the catalysis of various reactions, including, for example, dehydration, hydrocortisone, gidrogenizirovanii, desulfuromonas, hydrodesulfurised, dehydrohalogenation, reforming, steam reforming, cracking, hydrocracking, hydrogenation, dehydrogenation, isomerization, disproportionation, oxychlorination process, dehydrocyclization hydrocarbons or other organic compounds, oxidation reactions and/or recovery, the Claus reaction, treatment of exhaust gases of internal combustion engines, including afterburning of exhaust gases, in particular, in a three-component catalyst is, demetilirovania, mahanirvana, mahanirvana, shift-conversion, catalytic oxidation of soot generated by internal combustion engines, including diesel or petrol engines operating at low loads. Finally, the catalytic system and the composition of the invention can find application as catalysts for the selective reduction of NOxby reduction reaction of NOxany reductant hydrocarbon nature, as well as ammonia or urea, and, in the latter case, as catalysts for hydrolysis or decomposition of urea to ammonia (method SCR).

In the above-mentioned applications in catalysis compositions according to the invention can be used in combination with precious metals, and transition metals in the form of oxides, sulfides or other form, and thereby play the role of the media data for metals. The nature of these metals and methods of their introduction in the compositions carriers are well known to the person skilled in the art. For example, the metals may include gold, silver, platinum, rhodium, palladium or iridium, molybdenum, tungsten, Nickel, cobalt, manganese or vanadium; they can be used separately or in combination with each other and, in particular, can be incorporated into the compositions by impregnation.

When the processing is TKE exhaust systems described above by known methods installed in the exhaust of motor vehicles.

Further, the present invention is illustrated in the examples.

Example 1

This example relates to the preparation of the first method according to the invention the composition of the invention on the basis of zirconium oxide dispersed on a carrier of silica, when the respective mass fractions of oxides, equal to 30% and 70%.

Pre-made preparation of colloidal solution of ZrO2. To this concentrated solution of ZrO(NO3)2diluted permuteran water to obtain 600 ml of a solution of ZrO(NO3)2concentration equal to 80 g/l in terms of ZrO2pH is equal to 2. Instantly added a 28% solution of NH3so that the final pH reached 10, and observed the formation of sludge. The precipitate was filtered, then washed with 6 l of permuteran water. The filter cake is re-suspended in permuteran water (pH=7,5) and acidified by addition of 68% nitric acid solution so that the suspension concentration was 10 wt.% in terms of ZrO2. After keeping under stirring for one night got a transparent view of a colloidal solution, the particle size of which is measured using quasi-elastic light scattering, was 4 nm.

To 430 g of this colloidal solution under stirring was added aminocaproic acid is the fact that to increase pH and to stabilize it with the value of 4.5 (98% 6-aminocaproic acid obtained from Aldrich), and then with stirring, was added 100 g of a powder of silicon oxide (Rhoda Siloa) (specific surface area of 170 m2/g SPT 15%). Thus obtained suspension was maintained for 30 minutes under stirring, and then sprayed by setting Bchiat 110C. (outlet temperature 110C, inlet temperature 220C) and flow rate of 1 l/h of the Obtained powder was subjected to calcination in air at 700C for 4 hours.

Example 2

This example relates to the production of the third method according to the invention, a composition based on zirconium oxide on a carrier of silica at the respective mass fractions of oxides, equal to 10% and 90%.

Used silicon oxide represented Tixosil 68dry residue which at 900C was 90% (SPT 10%), and specific surface area of 160 m2/year Source of zirconium served a solution of ZrO(NO3)2dry residue which at 900C was 19.1 per cent. Dilute ammonia solution with a concentration of 10% was obtained by addition of two volumes of water to one volume of 28% NH3.

In the reactor received seed by introducing 59,80 g of silicon oxide (i.e. 54 g SiO2)diluted 771 ml permuteran water (70 g/l in terms of SiO2), then added 68% HNO3received the eat dispersion, pH of which was equal to 2. The seed crystal was added 31,41 g of a solution of ZrO(NO3)2(i.e. 6 g in terms of ZrO2)diluted permuteran with water to volume 86 ml (70 g/l in terms of ZrO2), then at a rate of 10 ml/min was added to the ammonia solution to achieve pH 9 (weight added ammonia solution was 32 g).

The resulting system was transferred into the autoclave and stirring was kept at a temperature of 150C for 2 hours.

The cooled mixture was then separated by filtration and washed at room temperature for a volume of water equal to the volume of the solution before filtration. After that, the filter cake was subjected to calcination in air at 700C for 4 hours.

Example 3

This example relates to the production of the third method according to the invention, a composition based on zirconium oxide on a carrier of silica at the respective mass fractions of oxides, equal to 30% and 70%.

Used the same silicon oxide, a source of zirconium and ammonia solution as in example 2.

In the reactor received seed by introducing 46,51 g of silicon oxide (i.e. 42 g SiO2), diluted with 600 ml permuteran water (70 g/l in terms of SiO2), then added 68% HNO3obtaining the dispersion, the pH of which was equal to 2. The seed crystal was added 94,24 g of a solution of ZrO(NO3)2(i.e. 18 g in terms of n is ZrO 2)diluted permuteran with water to volume 257 ml (70 g/l in terms of ZrO2), then at a rate of 10 ml/min was added to the ammonia solution to achieve pH 9 (weight added ammonia solution was 73 g).

Then in the same manner as in example 2, was carried out by autoclaving, washing and roasting.

Example 4

This example relates to the production by the third method according to the invention is a composition based on titanium oxide on a carrier of silica at the respective mass fractions of oxides, equal to 10% and 90%.

200 g of powdered silicon oxide Tixosil 68was dispersible in 570 ml of water to which was added HNO3to achieve a pH of 0.5. To the resulting medium was then added to 26.8 g TiOCl2(21 wt.% in terms of TiO2). After this was added 10% NH4OH to bring the pH to 7.

Then in the same manner as in example 2, was carried out by autoclaving, washing and roasting.

Example 5

This example relates to the production by the third method according to the invention is a composition based on titanium oxide on a carrier of silica at the respective mass fractions of oxides, equal to 30% and 70%.

155,6 g of powdered silicon oxide from example 2 was dispersible in 470 ml of water to which was added 13.3 g of concentrated HNO3to achieve a pH of 0.5. To the resulting environment, then d is balali 80,37 g TiOCl 2dissolved in 204,6 ml of water. After this was added 10% NH4OH to bring the pH to 7.

Then in the same manner as in example 2, was carried out by autoclaving, washing and roasting.

Example 6

This example relates to relates to the production of the third method according to the invention, a composition based on oxides of titanium and zirconium on the media of silicon oxide at the respective mass fractions of oxides, equal to 30% for ZrTiO4and 70% for SiO2.

155,6 g of powdered silicon oxide from example 2 was dispersible in 470 ml of water to which was added 10 g of concentrated HNO3to achieve a pH of 0.5. To the resulting medium was then added 30,9 g TiOCl2and 39,24 g ZrOCl2dissolved in 208 ml of water. After this was added 10% NH4OH to bring the pH to 7.

Then in the same manner as in example 2, was carried out by autoclaving, washing and calcination. RD-analysis allowed us to establish the presence of a single phase ZrTiO4.

The following examples are comparative examples in which applied the known impregnation method.

Comparative example 7

This example relates to the production of compositions based on titanium oxide on a carrier of silica at the respective mass fractions of oxides, equal to 10% and 90%.

Composition comprising 90% of SiO2and 10% of TiO2floor is made by dry impregnation 16,09 g of silica from example 2 only 6.64 g of the solution TiOCl 2c concentration of 25.1 wt.%, pre-diluted with 23.5 ml of N2O.

Then the powder was subjected to calcination in air at 700C for 4 hours. Way RD was confirmed by the presence of a single phase of anatase between 700 and 900C.

Comparative example 8

This example relates to the production of compositions based on titanium oxide on a carrier of silica at the respective mass fractions of oxides, equal to 30% and 70%.

A composition containing 70% SiO2and 30% of TiO2was obtained by dry impregnation 12,88 g of silica from example 2 20,49 g of the solution TiOCl2c concentration of 25.1 wt.%, pre-diluted with 9 ml of N2O.

Then the powder was subjected to calcination in air at 700C for 4 hours.

Comparative example 9

This example relates to the production of compositions based on titanium oxide on a carrier of silica at the respective mass fractions of oxides, equal to 30% and 70%.

A composition containing 70% SiO2and 30% of TiO2was obtained by dry impregnation of 22.5 g of silica from example 2 15,45 g of the solution TiOCl2c concentration of 25.1 wt.%, pre-diluted to 14.3 ml of N2O.

Then the powder was subjected to calcination in air at 700C for 4 hours. Way RD was confirmed by the presence of a single phase ZrTiO4between 700 and 1000C.

In the following next table p is Evegeny characteristics of the compositions, obtained in the various examples, i.e. their specific surface area by BET and the size of the oxide particles on the media at different temperatures of firing.

Table
ExampleCalcination at 900CSintering at 1000C
The surface on BET m2/gParticle size, nmThe surface on BET m2/gParticle size, nm
112951006

213721074
31694976
4133510710
5133 79815
612071008
Comparative 7112168523
Comparative 8102177721
Comparative 992117012

It is seen that the composition of the invention include the oxides on the carrier, the particle size of which is considerably less compared to the oxides in the compositions obtained by the known impregnation method.

1. Composition containing at least one oxide on a carrier consisting of zirconium oxide, titanium oxide or a mixed oxide of zirconium and titanium, or zirconium oxide and an oxide of at least one oxide of another element M selected among praseodymium, lanthanum, neodymium and yttrium,
printed on the media based on silicon oxide, characterized in that after firing at 900C for 4 hours OK the ID on the media is in the form of particles, printed on said media, the size of which is:
not more than 5 nm, if the oxide on the carrier obtained on the basis of zirconium oxide;
not more than 10 nm, if the oxide on the carrier obtained on the basis of titanium oxide;
not more than 8 nm, if the oxide on the carrier obtained on the basis of a mixed oxide of zirconium and titanium.

2. Composition containing at least one oxide on a carrier consisting of zirconium oxide, titanium oxide or a mixed oxide of zirconium and titanium, or zirconium oxide and an oxide of at least one oxide of another element M selected among praseodymium, lanthanum, neodymium and yttrium, supported on a carrier on the basis of silicon oxide, characterized in that after firing at 1000C for 4 hours, the oxide on the carrier is in the form of particles deposited on said media, the size of which is:
not more than 7 nm, if the oxide on the carrier obtained on the basis of zirconium oxide;
not more than 19 nm, if the oxide on the carrier obtained on the basis of titanium oxide;
not more than 10 nm, if the oxide on the carrier obtained on the basis of a mixed oxide of zirconium and titanium.

3. The composition according to claim 1 or 2, characterized in that the proportion of oxide on the carrier it is not more than 50 wt.%, more preferably not more than 30 wt.%.

4. The composition according to claim 1, characterized in that the oxide on the carrier is in the form of particles, the size of which is:
not over4 nm, if the oxide is zirconium oxide;
not more than 7 nm, if the oxide on the carrier is titanium oxide or a mixed oxide of zirconium and titanium.

5. The composition according to claim 2, characterized in that the oxide on the carrier is in the form of particles, the size of which is:
not more than 6 nm, if the oxide on the carrier is a zirconium oxide;
not more than 15 nm, if the oxide on the carrier is titanium oxide;
not more than 8 nm, if the oxide on the media is a mixed oxide of zirconium and titanium.

6. A method of obtaining a composition according to any one of the preceding paragraphs, characterized in that it comprises the following stages:
- cast colloidal dispersions of compounds of zirconium and/or titanium, and may compound of an element M selected from among praseodymium, lanthanum, neodymium and yttrium, in contact with the suspension media;
- spray drying thus obtained mixture;
- firing the dried product obtained in this way.

7. A method of obtaining a composition according to any one of claims 1 to 5, characterized in that it comprises the following stages:
- obtaining a liquid mixture containing at least one salt of zirconium or titanium, selected from nitrates, sulfates, acetates and chlorides, and possibly the element M selected among praseodymium, lanthanum, neodymium and yttrium,
and suspension media;
- heating the thus obtained mixture to a temperature equal to men is our least 100C;
the extract thus obtained precipitate;
- firing is referred to sludge.

8. A method of obtaining a composition according to any one of claims 1 to 5, characterized in that it comprises the following stages:
- obtaining a liquid mixture containing a suspension of the carrier and at least one salt of zirconium or titanium, selected from nitrates, sulfates, acetates and chlorides, and possibly the element M selected among praseodymium, lanthanum, neodymium and yttrium;
- bringing the just-mentioned mixture in contact with the base with the purpose of obtaining a precipitate;
- removing the precipitate obtained in this way;
- firing above the sediment.

9. The method according to claim 8, characterized in that the precipitate obtained after bringing it in contact with the ground, is subjected to aging.

10. The catalytic system, characterized in that it contains a composition according to any one of claims 1 to 5.



 

Same patents:

FIELD: chemistry.

SUBSTANCE: invention relates to a catalyst composition and methods (versions) of producing the catalyst composition for treating exhaust gases of internal combustion engines based on zirconium oxide, cerium oxide and yttrium oxide or based on zirconium oxide, cerium oxide and at least two oxides of rare-earth metals which are not cerium, with weight content of zirconium oxide of at least 20% and cerium oxide of not more than 70%. After calcination at 900C for 4 hours, the composition contains two pore populations, the corresponding diameter of the first of which ranges from 20 to 40 nm and the second from 80 to 200 nm.

EFFECT: obtaining a catalyst composition with a defined optimum porosity.

18 cl, 3 tbl, 1 dwg, 15 ex

FIELD: chemistry.

SUBSTANCE: invention relates to method of obtaining water dispersion of zirconium oxide, which includes interaction of zirconium salt with alkali in water with obtaining suspension of zirconium oxide particles, filtration, washing and re-pulping suspension, addition of organic acid to obtained suspension in amount one mole part or more per mole part of zirconium in suspension, hydrothermal processing of obtained mixture at temperature 170C and higher for not less than an hour and washing obtained water dispersion of zirconium oxide particles. Invention also relates to method of obtaining water dispersion of zirconium oxide solid solution, which contains, at least, one stabilising element, selected from aluminium, magnesium, titanium and rare earth elements. Invention additionally claimed method of obtaining zirconium oxide dispersion, dispersion medium of which is organic solvent, where claimed method contains replacement of dispersion medium of water dispersion of zirconium oxide, obtained by method, described above, with organic solvent.

EFFECT: dispersion of zirconium oxide contains fine particles of zirconium oxide, uniformly dispersed in dispersion medium, and has high transparency.

12 cl, 2 tbl, 1 ex

FIELD: chemistry.

SUBSTANCE: invention relates to composition, based on oxides of zirconium, cerium and at least one rare earth metal element, different from cerium, to method of its obtaining and to its application for purification of exhaust gases of internal combustion engines. Composition, based on oxides of zirconium, cerium and at least one rare earth metal element, different from cerium, contains cerium oxide not more than 50 wt % and has after burning at 1000C for 6 hours maximal temperature of reductability not more than 500C and specific surface at least 45 m2/g. method of obtaining composition includes carrying out continuous reaction in mixture of compounds of zirconium, cerium and other rare earth metal element, different from cerium with basic compound with time of being in reactor not longer than 100 milliseconds, obtained sediment is heated, and then combined with surface-active substance before burning Catalytic system, containing claimed composition, and method of purification of exhaust gases of internal combustion engines with application of described above composition or catalytic system as catalyst, are described.

EFFECT: invention ensures obtaining composition, combining high specific surface and maximal reductability at lower temperature.

16 cl, 5 ex, 2 tbl, 2 dwg

FIELD: chemistry.

SUBSTANCE: invention can be used in chemical industry. The zirconium oxide dispersion is obtained by reacting a zirconium salt with an alkali in water to obtain a suspension of zirconium oxide particles. The suspension is filtered, washed and repulped. An organic acid is added to the obtained suspension in amount of one molar part or more per molar part of zirconium in the suspension and the suspension is subjected to hydrothermal treatment at temperature of 170C or higher. The obtained aqueous dispersion of zirconium oxide particles is then washed and thickened. The zirconium oxide dispersion contains zirconium oxide particles in amount of 20 wt % or more, has low viscosity and is characterised by a transmittance factor of 35% or more at wavelength of 400 nm, transmittance factor of 95% or more at wavelength of 800 nm and viscosity of 20 mPas or less at temperature of 25C.

EFFECT: zirconium oxide dispersion can be used in optical products, such as sealing resin for LEDs or an antireflection film.

13 cl, 2 tbl

FIELD: chemistry.

SUBSTANCE: invention can be used in production of dense wear-resistant ceramic and solid electrolytes. The method of producing powder of a zirconium, yttrium and titanium composite oxide involves preparing a starting solution of nitrates, adding an organic acid and a titanium-containing compound into said solution, followed by heat treatment. The organic acid used is glycine in amount of 1.6-2.5 mol per 1 g-atom of the sum of metal cations (Zr+4+Ti+4+Y+3). The titanium-containing compound used is a hydrolysable titanium compound with the ratio Zr+4:Ti+4=(0.99-0.85):(0.15-0.01). The starting solution is further mixed with 30% hydrogen peroxide with the ratio H2O2:Ti+4=(4.7-12):1. The hydrolysable titanium compound used can be titanium tetrabutylate or titanium sulphate or titanium tetrachloride.

EFFECT: invention prevents waste discharge, reduces power consumption and simplifies production of nanopowder of a zirconium, titanium and yttrium composite oxide.

3 cl, 3 ex

FIELD: chemistry.

SUBSTANCE: invention relates to a composition based on cerium oxide and zirconium oxide having special porosity, which can be used in catalyst systems for treating exhaust gases. The composition is based on cerium oxide and zirconium oxide containing at least 30 wt % cerium oxide which, after calcination at temperature of 900C for 4 hours, has two types of pore distribution, the diameters of which, for the first type of distribution, lie in the range from 5 nm to 15 nm for a composition having cerium oxide content of 30% to 65%, or from 10 nm to 20 nm for a composition having cerium oxide content higher than 65% and, for the second type of distribution, in the range from 45 nm to 65 nm for a composition having a cerium oxide content of 30% to 65% or from 60 nm to 100 nm for a composition having cerium oxide content higher than 65%. The method of producing the composition includes steps of: forming a first liquid medium containing a zirconium compound, a cerium (III) compound, sulphate ions, an oxidising agent and, optimally, a compound of a rare-earth element other than cerium; bringing the medium into contact with a base, whereby a precipitate is formed; separating and washing the precipitate; suspending the precipitate in water and heat treatment of the obtained medium at temperature of 90C; and separating and calcining the precipitate.

EFFECT: composition has high specific surface area and provides good diffusion of gases.

17 cl, 2 dwg, 2 tbl, 2 ex

FIELD: chemistry.

SUBSTANCE: invention can be used in chemical industry. Composition for obtaining thin film of complex oxides of zirconium, phosphorus and calcium contains ethyl alcohol, preliminarily distilled and dried to 96 wt %, zirconium oxochloride, calcium chloride and orthophosphoric acid with the following component ratio, wt %: zirconium oxochloride - 4.7-6.8; calcium chloride - 2.6-4.4; orthophosphoric acid - 0.5, ethyl alcohol - the remaining part.

EFFECT: claimed invention makes it possible to obtain thin films, possessing high refractive indices.

3 ex

FIELD: chemistry.

SUBSTANCE: invention relates to a method of producing nanoparticles of a transition metal oxide coated with amorphous carbon. A liquid mixture containing as precursors at least one alkoxide of a transition metal selected from Ti, Zr, Hf, V, Nb and Ta, an alcohol and excess acetic acid with respect to the transition metal is diluted with water to obtain an aqueous solution. Precursors are contained in the solution in a molar ratio which is sufficient to prevent or significantly limit sol formation. The transition metal, carbon and oxygen are contained in said solution in a stoichiometric ratio which corresponds to the composition of nanoparticles. The aqueous solution is freeze-dried and the freeze-dried product undergoes pyrolysis in a vacuum or an inert atmosphere to obtain nanoparticles. The obtained nanoparticles can be subjected to carbothermal reduction to obtain carbide nanoparticles.

EFFECT: obtaining nanoparticles with a high degree of purity and smaller average size.

15 cl, 4 ex

FIELD: chemistry.

SUBSTANCE: invention relates to field of chemistry, in particular, to catalytic compositions, applied as catalyst. Claimed are catalytic composition, methods of its application and catalytic system. Catalytic system, which contains at least one oxide on carrier, selected from zirconium oxide, titanium oxide or mixed zirconium and titanium oxide, applied on aluminium oxide or aluminium oxyhydroxide carrier, and which has after burning at 900C for 4 hours size of particles of oxide on carrier not larger than 10 nm, if oxide on carrier is obtained on zirconium oxide base or not larger than 15 nm, if oxide on carrier is obtained on the base of titanium oxide or mixed zirconium and titanium oxide. Catalytic system contains claimed catalytic composition.

EFFECT: ensuring high catalytic properties of catalyst work at high and room temperature with preservation of dispersity of active phase on carrier.

15 cl, 1 dwg, 7 ex

FIELD: chemistry.

SUBSTANCE: invention relates to filler materials made of nanoparticles for use in composite materials, including dental composite materials. The filler materials contain clusters of silica and zirconium dioxide nanoparticles. The filler materials can be obtained by mixing a sol of silica nanoparticles with a sol of pre-formed crystalline particles of zirconium nano-oxide.

EFFECT: filler materials provide the desired optical properties, such as opalescence, and are useful in dental compositions.

25 cl, 4 tbl, 2 dwg

FIELD: chemistry.

SUBSTANCE: invention can be used in making lithium cells used in rechargeable batteries. Lithium titanate of formula Li4Ti5O12-x, where 0<x<0.02, is obtained by preparing a mixture of titanium oxide and a lithium-based component, wherein the lithium-based component and titanium oxide are present in the obtained mixture in amounts required to provide atomic ratio of lithium to titanium of 0.8. The lithium-based component includes lithium carbonate powder and lithium hydroxide powder. The obtained mixture is used as a calcination precursor. Further, the mixture is sintered in a gaseous atmosphere containing a reducing agent to form lithium titanate. The sintering step causes a solid-phase reaction between the lithium carbonate powder and titanium oxide and a liquid-solid-phase reaction between lithium hydroxide powder and titanium oxide.

EFFECT: invention enables to obtain lithium titanate having high electron conductivity and electrochemical capacitance.

9 cl, 13 dwg, 2 tbl

FIELD: physics.

SUBSTANCE: invention relates to semiconductor electronics materials and can be used to make components of spintronic devices, which combine a source and a receiver of polarised spins of charge carriers in a ferromagnetic semiconductor/nonmagnetic semiconductor/ferromagnetic semiconductor ternary heterostructure. The ferromagnetic semiconductor material is a ferromagnetic film of semiconductor titanium dioxide doped with vanadium in amount of 3-5 at % with respect to titanium, having a crystalline structure of anatase and grown on a dielectric substrate. The film of doped titanium dioxide is further implanted at room temperature with cobalt ions with a dose of (1.3-1.6)1017 cm-2 and, at temperatures not lower than 300 K in the absence of an external magnetic field, retains remnant magnetisation of not less than 70% of the saturation magnetisation value.

EFFECT: producing ferromagnetic semiconductor material, having high magnetisation at room temperature and higher temperatures in the absence of an external magnetic field.

3 cl, 3 dwg, 3 ex

Titanium dioxide // 2502761

FIELD: chemistry.

SUBSTANCE: coloured composition contains particulate material which scatters radiation in the near-infrared region and one or more colouring substance. The particulate material and colouring substance are dispersed. Said material is selected from titanium dioxide, doped titanium dioxide and combinations thereof, and has average crystal size greater than 0.40 mcm, and particle size distribution where 30% or more particles are smaller than 1 mcm. Material consisting of titanium dioxide particles can be used for adding to the coloured composition, said material having a coating which contains one or more oxide materials, which provides low levels of photocatalytic activity of titanium dioxide.

EFFECT: invention increases reflection of radiation in the near-infrared region, while simultaneously reducing reflection of visible light of dark or intensely coloured compositions.

39 cl, 8 dwg, 7 ex

FIELD: chemistry.

SUBSTANCE: dense layer of silicon dioxide is deposited on the surface of titanium dioxide particles from a gas phase, said silicon dioxide layer being doped with at least one doping element selected from a group which includes Sn, Sb, In, Y, Zn, F, Mn, Cu, Mo, Cd, Ce, W and Bi or mixtures thereof. A dense layer of silicon dioxide can be deposited on the surface of titanium dioxide from a liquid phase, said silicon dioxide layer being doped with at least one doping element selected from a group which includes Sb, In, Ge, Y, Nb, F, Mo, Ce, W and Bi or mixtures thereof.

EFFECT: invention increases photostability of titanium dioxide pigment particles.

27 cl, 18 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to a method of producing nanoparticles of a transition metal oxide coated with amorphous carbon. A liquid mixture containing as precursors at least one alkoxide of a transition metal selected from Ti, Zr, Hf, V, Nb and Ta, an alcohol and excess acetic acid with respect to the transition metal is diluted with water to obtain an aqueous solution. Precursors are contained in the solution in a molar ratio which is sufficient to prevent or significantly limit sol formation. The transition metal, carbon and oxygen are contained in said solution in a stoichiometric ratio which corresponds to the composition of nanoparticles. The aqueous solution is freeze-dried and the freeze-dried product undergoes pyrolysis in a vacuum or an inert atmosphere to obtain nanoparticles. The obtained nanoparticles can be subjected to carbothermal reduction to obtain carbide nanoparticles.

EFFECT: obtaining nanoparticles with a high degree of purity and smaller average size.

15 cl, 4 ex

FIELD: chemistry.

SUBSTANCE: titanium dioxide based pigment contains titanium dioxide particles in rutile form, having a coating. The coating contains aluminium phosphate, aluminium oxide, titanium oxide and silicon oxide. The particles are characterised by specific surface area, calculated according to a Brunauer-Emmet-Teller (BET) equation, of at least 15 m2/g. To obtain coated pigments, an aqueous suspension of uncoated titanium dioxide particles is prepared first, followed by addition of aluminium-containing and phosphorus-containing components. Further, while maintaining pH 4-9, an alkaline silicon-containing component and at least one pH regulating component, one of which is an acidic titanium-containing component, are then added. The formed suspension is then filtered, washed and dried and the precipitate is ground to obtain coated particles.

EFFECT: invention increases opacity of decorative paper.

22 cl, 5 ex, 1 tbl

FIELD: chemistry.

SUBSTANCE: invention relates to production of photocatalytic coatings of nanocrystalline titanium dioxide. Described is a composition for obtaining a photocatalytic coating based on nanocrystalline titanium dioxide with average particle size of 5-100 nm and specific surface area of 10-300 m2/g, water and a stabiliser, characterised by the following composition: TiO2 - 1-10 wt %, H2O - 85-98 wt %, stabiliser - 1-5 wt %, wherein the nanocrystalline titanium dioxide has a phase composition, 50-100% of which consists of "anatase" crystalline modification. Described is a method of preparing said composition, involving mixing titanium dioxide, water and stabiliser and subjecting the obtained mixture to ultrasound, wherein the mixture of titanium dioxide, stabiliser and water, taken in amount of not more than 10% of its total volume, is masticated for not less than 5 minutes into a homogeneous paste-like mass into which, while stirring continuously, the remaining amount of water is added, and the mixture then subjected to ultrasound with operating frequency of 35 kHz and generator power of 50 W for not more than 15 minutes at room temperature. Described is a method of obtaining a photocatalytic coating on a glass substrate using said composition, involving immersing the substrate in the composition, drying the substrate at room temperature and calcining in an atmosphere of air at temperature of 300-600C and cooling, characterised by that, before coating, the surface of the glass substrate is first treated with a freshly prepared solution obtained from concentrated sulphuric acid and 30% hydrogen peroxide solution in volume ratio H2SO4:H2O2=7:3, and then washed with distilled water to pH 6-7 and subjected to ultrasonic treatment with operating frequency of 35 kHz and generator power of 50 W for 5-30 minutes at room temperature; the glass substrate is then immersed in the composition prepared as described above for not less than 5 minutes, dried for not less than 24 hours in the presence of a drying agent and calcined in an atmosphere of air for 10-15 minutes, and heating and cooling is carried out at a rate of not more than 1.5C/min.

EFFECT: efficient and stable photocatalytic coating is obtained, which is suitable for use in flowing water treatment systems.

5 cl, 6 dwg, 2 tbl, 4 ex

FIELD: chemistry.

SUBSTANCE: invention relates to field of chemistry, in particular, to catalytic compositions, applied as catalyst. Claimed are catalytic composition, methods of its application and catalytic system. Catalytic system, which contains at least one oxide on carrier, selected from zirconium oxide, titanium oxide or mixed zirconium and titanium oxide, applied on aluminium oxide or aluminium oxyhydroxide carrier, and which has after burning at 900C for 4 hours size of particles of oxide on carrier not larger than 10 nm, if oxide on carrier is obtained on zirconium oxide base or not larger than 15 nm, if oxide on carrier is obtained on the base of titanium oxide or mixed zirconium and titanium oxide. Catalytic system contains claimed catalytic composition.

EFFECT: ensuring high catalytic properties of catalyst work at high and room temperature with preservation of dispersity of active phase on carrier.

15 cl, 1 dwg, 7 ex

Powders // 2471711

FIELD: chemistry.

SUBSTANCE: invention can be used in production of electrochemical devices such as batteries. Powder of titanium suboxides contains Ti4O7, Ti5O9 and Ti6O11. Ti4O7, Ti5O9 and Ti6O11 constitute in total more than 92 wt % of powder and Ti4O7 is present in amount higher than 30 wt % of entire powder mass. Powder of said composition is used for manufacturing electrodes and such moulded articles as tubes and plates.

EFFECT: invention makes it possible to reduce resistance of said articles and their weight, increase corrosion resistance.

15 cl, 5 tbl, 2 ex

FIELD: chemistry.

SUBSTANCE: invention can be used in cosmetic industry when producing preparations which protect the skin from UV radiation. The finely dispersed titanium dioxide-based composite contains finely dispersed titanium dioxide particles which are combined with one or more polymers containing constituent monomers in form of carboxylic acid and/or a carboxylic acid derivative represented by the formula , where R is a C1-C15 alkenyl group, wherein hydrogen atoms can be substituted with a carboxyl group or a hydroxyl group; and X is a hydrogen atom or an alkali metal or a polyoxyethylene or polyoxypropylene group with 1-12 bonded moles. The average peak width of the maximum diffraction intensity assigned to titanium dioxide crystals is 2.0 or less in X-ray powder diffraction analysis.

EFFECT: invention increases transparency and stability of finely dispersed titanium dioxide-based composite, UV radiation absorption capacity thereof and re-dispersion capacity thereof.

11 cl, 9 tbl, 12 ex

FIELD: chemistry.

SUBSTANCE: invention relates to the field of plasmochemistry and can be applied for production of fullerenes and nanotubes. A carbon-containing raw material is decomposed in a gas discharge. For this purpose, first, inflamed is a volume glow discharge in a mixture of gaseous hydrocarbons and inert gas under pressure of 20-80 Torr. Then, under visual observation burning of the glow discharge with a constricted cathode area and diffuse positive column is obtained. Products of decomposition are precipitated in the form of soot.

EFFECT: carrying out process in a strongly non-equilibrium electric discharge makes it possible to increase the speed of soot obtaining and 9,6 times increase the output of nanotubes and fullerenes per unit of put in energy.

1 dwg

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