RU2390583C2 - Method of preparing concentrate of silver oxides - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to methods of preparing a concentrate of silver oxides and can be used in making highly effective preparations in medicine and veterinary science. The method involves pouring distilled water at 80°C into a chemically clean glass vessel, immersing a silver ion source holder into the water, connecting a direct current circuit and stirring the solution after appearance of electrical conductivity detected by a milliamperemetre. Stirring is repeated several times before appearance of excess concentration of silver ions in form of a brown, then black colloidal solution. The process is stopped when electrical conductivity falls. Silver oxides are removed from the electrodes into a prepared solution. The remaining solution cooled to room temperature is then separated in a centrifuge. The purified solution is then recycled and the precipitate with a small amount of water is poured into a container made from dark glass with minimal air space for subsequent storage.

EFFECT: obtaining a concentrate of silver (I) oxide which can be used to prepare a solution of silver ions for medical preparations by dissolving in distilled water and filtration of insoluble silver oxides.

2 cl

Description

The invention relates to methods for producing silver-containing concentrates, for example silver oxide (1), and can be used in the manufacture of highly effective drugs for medicine and veterinary medicine having low toxicity and allergenicity, as well as reliable reproducibility of physico-chemical characteristics.

A known method of producing silver oxide (I) under the action of sodium hydroxide or potassium hydroxide on a solution of nitrogen-silver salt by reaction

2AgNO ₃ + 2KOH = Ag ₂ O + H ₂ O + 2KNO ₃

As a result of the reaction, a brown-black precipitate of silver oxide (I) is released (see Brockhaus and Efron Encyclopedic Dictionary (Reproduction of a publication by F.A. Brockhaus-I.A. Efron in 1890 by the TERRA Publishing Center, 1992, vol. 58, p. 675).

The disadvantage of this method is the presence in the precipitate of nitrates, which reduces the possibility of its use for medical purposes. An aqueous solution of silver oxide (I) obtained by this method can only be used externally as an antiseptic.

The method for producing a silver oxide concentrate using metallic silver, distilled water, a direct current source, and a milliammeter in series with a circuit proposed in the framework of the present application for the invention has no analogues.

Obtaining a concentrate is as follows.

Distilled water heated to 80 ° C is poured into a clean glass dish. A silver ionizer cassette is immersed in water, a direct current source is connected.

At the beginning of the process, the milliammeter shows zero values (0.00 mA), there are no ions in the water, and accordingly there is no electron current in the circuit. However, due to the fact that there is voltage at the electrodes, the process of decomposition of the distillate into hydrogen, which moves slowly to the cathode, and oxygen, which moves to the anode and causes anodic oxidation, forms a film of silver oxide (I), which, in turn, , spontaneously dissolves in water with dissociation into silver and hydroxyl ions, giving rise to the conductivity of part of the solution, limited by the volume of the inner part of the cartridge.

After the appearance of electrical conductivity, indirectly recorded by a milliammeter in the form of small current values (0.01-0.02 mA) and indicating that a part of the solution enriched in silver ions appeared inside the cassette, the solution is mixed with the cassette, transferring the enriched part of the solution to the general solution, thereby increasing the conductivity of the general solution. Repeatedly repeating the cycle of anodic oxidation and, accordingly, enrichment of the solution of the inner part of the ionizer cassette and mixing (unloading the enriched part into the general solution), they achieve the effect of first saturation and then supersaturation of the solution. Stirring is repeated several times until an excessive concentration appears in the form of a drilling, then blackening colloidal solution. In the process of electrochemical dissolution in an electrolyte (according to the Faraday law), there is also a process of deposition of silver metal on the cathode.

Metallic silver deposited on the cathode forms a kind of loose spongy coating, which leads to a drop in the electrical conductivity of the solution, while the milliammeter starts to show values several milliamps below the maximum value reached. The process, accordingly, due to inefficiency, is stopped.

The oxides from the electrodes are cleaned into the prepared solution. Then the solution is cooled to room temperature and set aside for crystallization of silver oxides. The finished solution is a medium-strength base with pH = 9.0-9.5, where silver (I) oxide is dissociated into Ag + and OH ^- ions due to ion hydration. During sedimentation, the solution is molarized: 2AgOH = Ag ₂ O · H ₂ O.

This process is controlled by lowering and stabilizing the pH to 8.0. As a result of crystallization, an intermediate compound is formed, aqueous silver oxide Ag ₂ O · H ₂ O or, more correctly, crystalline silver hydrate [AgOH] ₂ , where a water molecule enters the crystalline structure of silver (I) oxide.

When the precipitate is dried, water is lost, and alkaline properties disappear with it. So, for example, dried silver (I) oxide when dissolved in a distillate (saturated solution) gives a very weak alkalinity pH = 7.0-7.1, and aqueous silver oxide gives a stable alkalinity pH = 8.0, which very significantly increases healing properties of silver oxide (I). For this reason, drying of the concentrate is unacceptable.

The precipitate, consisting of silver oxide (I) with impurities of insoluble particles of silver oxide (II) and metallic silver, is separated in a centrifuge.

The purified solution is put back into circulation, and the precipitate with a small amount of water is poured into a dark glass container with a minimum air gap for subsequent storage.

The process is conducted in red or orange light.

As a result of these operations, a silver (I) oxide concentrate is obtained, which can be used to obtain a solution of ionic silver for medical preparations by dissolving in distilled water and filtering insoluble silver oxides.

Insoluble oxides are disposed of and transferred to the State Fund for subsequent refining.

Claims (2)

1. A method of producing a silver oxide concentrate, characterized in that distilled water heated to 80 ° C is poured into a chemically clean glassware, then a silver ionizer cassette is immersed in water, connected to a direct current circuit, after the appearance of electrical conductivity detected by a milliammeter, mix the solution, stirring is repeated several times until excessive concentrations of silver ions appear in the form of a browning, then blackening colloidal solution, after a drop in the electrical conductivity otsess stopped brushes oxides of silver electrodes in a solution is prepared, then cooled to room temperature, the supernatant solution is separated in a centrifuge, the purified solution is newly put into circulation, and the precipitate with a small amount of water poured into the container of dark glass with minimal air gap for storage. 2. The method according to claim 1, characterized in that the process for producing silver-containing concentrate is carried out under red or orange light.