RU163456U1 - DEVICE FOR SYNTHESIS OF FULLERENES AND ENDOEDRAL FULLERENES IN A ROTATING CARBON-HELIUM PLASMA - Google Patents

Abstract

A device for producing fullerenes in a carbon-gel plasma of a high-frequency arc at atmospheric pressure on alternating current, including a chamber with an even number of identical horizontal electrodes and one vertical electrode, characterized in that the chamber is water-cooled sealed metal, and that the device further comprises a single-turn an inductor, and the axes of the horizontal electrodes are perpendicular to its axis and lie in its plane, and the axis of the vertical electrode coincides with the axis of this th coil, while the coordination circuit of a single-turn coil and the coordination circuit of discharges are connected to a common generator, the coordination circuit of a single-turn coil consisting of an amplifier, a transformer, and a capacitor, and each of the coordination circuits of the discharges includes a phase shifter, an amplifier, a transformer, and a series oscillatory circuit consisting of capacitor and inductor.

Description

The utility model relates to the field of plasma synthesis of nanomaterials and can be used for the synthesis of carbon nanostructures.

A device is known where in the reactor chamber a discharge is carried out between at least two graphite electrodes located at an angle to each other. The chamber carries out an arc discharge of alternating current. A vertically water-cooled sleeve is suspended inside the chamber. Between the walls of the reactor and the sleeve there is a gap for the convective flow of plasma-forming gas [WO 2014152062, IPC С01В 31/02, С25В 1/00, publ. 09/25/20014].

The disadvantage of this device is that the number of fullerenes and especially the endohedral fullerenes formed in the carbon condensate is small. This is explained by the fact that in this geometry the region of a plasma with a high temperature smoothly (not fast enough) passes into the region of a plasma with a low temperature. Fullerenes, and especially endohedral fullerenes, being more stressed structures, manage to transfer to less stressed graphite structures.

The closest in technical essence to the claimed technical solution is the device according to the patent [RU 2320536 IPC С01В 31/00, В82В 3/00, publ. March 27, 2007], described in an arc method for synthesizing a fullerene mixture in a plasma at atmospheric pressure in a helium stream. In the chamber there is an even number of horizontal identical graphite electrodes made in the form of rods, and one vertical electrode. The arc is powered by the use of an alternating current source of the kilohertz range and a direct current source. At least 98% of the evaporated graphite passes into fullerene-containing soot, due to the proposed configuration, the location of the electrodes and the supply of alternating current.

The disadvantage of this device is that the content of fullerenes in carbon condensate is low. This is due to the fact that the temperature and electron concentration, and most importantly their gradients, only in a small, near-surface layer of the volume occupied by the plasma correspond to the optimal assembly values of fullerene molecules.

The technical result of the utility model is to increase the content of fullerenes in the carbon condensate by 4-6%.

The technical result is achieved in that in a device for producing fullerenes in a carbon-gel plasma of a high-frequency arc, at atmospheric pressure on an alternating current, including a chamber with an even number of identical horizontal electrodes and one vertical electrode, the new one is that the chamber is a water-cooled sealed metal, and also the fact that the device further comprises a single-turn inductor, the axes of the horizontal electrodes being perpendicular to its axis and lying in its plane, and the vertical electrode coincides with the axis of this coil, while the matching circuit of a single-turn coil and the matching circuit of discharges are connected to a common generator, and the matching circuit of a single-coil coil consists of an amplifier, transformer and capacitor, and each of the matching circuits of discharges includes a phase shifter, amplifier, transformer and serial an oscillatory circuit consisting of a capacitor and an inductor.

In FIG. 1. presents the electrical circuit of the device.

In FIG. 2. A schematic representation of the discharge plasma is presented.

The electrical circuit of the device is shown in FIG. 1., where 1 is a water-cooled sealed metal chamber, 2, 2 ′, 3, 3 ′ are horizontal identical graphite electrodes, 4 is a vertical (central) graphite electrode, 5 is a high-frequency generator of the initial frequency, 6 and 6 ′ is a phase shifter, 7 , 7 ′ and 7 ″ are power amplifiers, Tr.1, Tr.1 ′ and Tr.2 are matching transformers, 8, 8 ′ and 8 ″ are capacitors, 9, 9 ′ are inductors, 10 are single-turn inductors.

A schematic representation of the discharge plasma is shown in FIG. 2., where 2, 2 ′, 3, 3 ′ are horizontal identical graphite electrodes, 4 is a vertical (central) graphite electrode, 11 is a discharge plasma.

The device operates as follows:

In a water-cooled sealed metal chamber 1 between the electrodes 2, 2 ′, 3, 3 ′ and 4, an arc discharge is initiated by closing them. The signal from the generator 5 is fed to amplifier 7, and through phase shifters 6 and 6 ′ to amplifiers 7 ′ and 7 ″. Next, the amplified signal is fed to the matching transformers Tr.1, Tr.1 ′ and Tr.2. Then the voltage is applied to the series oscillatory circuits, consisting of capacitors 8, 8 ′, 8 ″ and inductors 9, 9 ′ and 10. The electrode 4 is intermediate and is not connected to anything.

, между магнитным полем одновитковой катушки и токами обеих дуг (рис. 1) возникает сила Лоренца, под действием которой оба разряда принимают форму дуги, лежащей в плоскости одновитковой катушки. Для описанных выше фазовых соотношений между токами мы имеем:

.A single-coil inductor 10 was introduced into the installation, while the axes of the electrodes 2, 2 ′ and 3, 3 ′ providing a discharge are perpendicular to the axis of the coil and lie in its plane, and the axis of the electrode 4 coincides with the axis of the single-turn coil and is perpendicular to its plane. The frequencies of the current in the single-turn coil and the discharge currents between the electrodes coincide, since they are connected through their matching circuits to a common generator 5. The current phases of both arcs, using phase shifters in their matching circuits, are set equal and shifted by π / 2 with respect to the current single turn coil. Thus, this circuit (Fig. 1) ensures that the currents of both arcs are in phase and their phase shift from the current phase of a single-turn coil by π / 2. In accordance with Ampere's law

, between the magnetic field of a single-turn coil and the currents of both arcs (Fig. 1), a Lorentz force arises, under the influence of which both discharges take the form of an arc lying in the plane of a single-turn coil. For the above phase relationships between currents, we have:

.

, а между электродами 3*, 2*,

.here, the X and Y axes lie in the plane of the single-turn coil and coincide with the axes of the electrodes 3, 2 and 3 *, 2 *, respectively, and the Z axis is perpendicular to the plane of the single-turn coil. Thus, the Lorentz force acting on the arc between the electrodes 3 and 2,

, and between the electrodes 3 *, 2 *,

.

Those. half a period, the discharge between electrodes 2 and 3 has an arc shape displaced toward the electrode 2 ′ and half a period toward the electrode 3 ′ and the discharge between 2 ′ and 3 ′ also has a half wave form an arc displaced toward 2. and a half period toward electrode 3. Since in the gap between one pair of electrodes is another pair of electrodes, then the arc current between the electrodes 3-2 flows along the circuit 3-2′-2, for one half-period and 3-3′-2, for another half-period. The arc current between the electrodes 3′-2 ′ flows along the circuit 3′-3-2 ′ during one half-cycle and 3′-2-2 ′ during the other half-cycle. Thus, due to the force action of the magnetic field on the currents in the discharges and due to the binding of both discharges to all four electrodes, a plasma ring appears, Fig. 2. In contrast to the plasma cylinder, the surface of the plasma ring is significantly larger, due to which an increase in the production efficiency of fullerenes in the presented utility model is achieved.

Claims (1)

A device for producing fullerenes in a carbon-gel plasma of a high-frequency arc at atmospheric pressure on alternating current, including a chamber with an even number of identical horizontal electrodes and one vertical electrode, characterized in that the chamber is water-cooled sealed metal, and that the device further comprises a single-turn an inductor, and the axes of the horizontal electrodes are perpendicular to its axis and lie in its plane, and the axis of the vertical electrode coincides with the axis of this th coil, while the coordination circuit of a single-turn coil and the coordination circuit of discharges are connected to a common generator, the coordination circuit of a single-turn coil consisting of an amplifier, a transformer, and a capacitor, and each of the coordination circuits of the discharges includes a phase shifter, an amplifier, a transformer, and a series oscillatory circuit consisting of capacitor and inductor.

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