CZ308908B6 - Ecological glass matrix containing effective antibacterial ions - Google Patents

Abstract

Ecological glass matrix, as loose or sintered particles situated in blocks and which is for filling continuous systems for water sanitation, has a particle granulometry of 1 to 10 mm and contains 5 to 15 by weight parts of sodium oxide Na2O, 10 to 30 by weight parts of lithium oxide Li2O, 20 to 40 wt. parts of boron trioxide B2O3 and 20 to 50 by weight parts of silica SiO2.

Description

Ecological glass matrix containing effective antibacterial ions

Field of technology

The invention relates to an ecological glass matrix containing effective antibacterial ions, which is in the form of free or sintered particles situated in blocks intended for filling continuous systems for water sanitation.

Prior art

There are currently various systems designed to reduce microbial water pollution. One known solution is filtration through membranes with a specific morphology, which are based on nanofibrous polymeric structures or polymers with a specific porosity. Despite the high efficiency of these technologies, there are also shortcomings in their insufficient mechanical properties and sensitivity to mechanical impurities. However, the most significant shortcoming of the above technologies is the high pressure drop, which must be compensated by the supply of a considerable amount of energy. However, this is unrealistic for many practical applications (eg use in crisis situations).

Furthermore, filters are known, which are included in the pipeline system and in the declared effect promise even unrealistic results such as the removal of pesticides, microbial spores, etc. They mostly use the antimicrobial properties of silver, but its impact on the environment is debatable. This field includes, for example, the solution according to the international patent application WO 2005087675 A1, the subject of which is an antibacterial glass which, in direct contact with water, releases silver ions and thus has an antibacterial effect. Antibacterial glass is suitable for water purifiers for antibacterial treatment with silver ions during or after cleaning. It has a particle size in the range of 1 to 50 mm and the amount of silver ion to be released into the water is in the range of 0.5 to 100 mg / g in 24 hours. The said patent application further addresses a method for producing a given antibacterial glass.

A common disadvantage of all solutions based on the release of antibacterial ions, including silver ions, from surface-enriched systems is the fact that after depletion of this surface layer the system is ineffective and must be completely replaced by a new active surface system.

To eliminate the above-mentioned shortcomings, a solution according to the Czech utility model CZ 33559 Ul. Glass frit for filling filter devices for sanitation of service water. This solution consists in that the glass frit with a granulometry of 1 to 5 mm is formed by a glass matrix which contains 20 to 40 wt. parts of silica (S1O2), 20 to 46 wt. parts of boric oxide (B2O3) and 25 to 35 wt. parts of sodium oxide (Na2O) or potassium (K2O). In principle, this is certainly the most technically perfect solution so far. The problem, however, is the need to further optimize the composition of the glass matrix to achieve higher antibacterial efficacy and the associated possibility of higher flow of disinfected water through the filtration system.

The essence of the invention

The ecological glass matrix containing effective antibacterial ions according to the invention contributes to a large extent to solving the above-mentioned problem of optimizing the composition of the glass matrix. The essence of the invention lies in the fact that this glass matrix has a particle size granulometry of 1 to 10 mm and contains 5 to 15 wt. parts of sodium oxide (Na2O), 10 to 30 wt. parts of lithium oxide (L12O), 20 to 40 wt. parts of boric oxide (B2O3) and 20 to 50 wt. parts of silica (S1O2).

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In comparison with the above-mentioned glass frit according to utility model CZ 33559U1, the ecological glass matrix according to the invention has a new chemical composition containing lithium ions, which increase the antibacterial effect of boron ions due to the synergistic effect. In particular, this can be documented by parameter A20 expressing the antibacterial activity against Escherichia coli CCM 4517 at a contact time of 20 minutes (see Table 1 in Example 1), where the value of A20 is 5.2. For glass frit according to utility model CZ 33559 U1, this value reaches only A20 = 2.9. Since these are data in logarithms, a comparison of these values results in a 200-fold higher antibacterial activity of the ecological glass matrix according to the invention. In addition, this glass matrix is much more resistant to spontaneous autoaggregation (stickiness), which reduces the effective surface of the aggregated frit. This new composition is therefore much more suitable for industrial use, where it allows a much higher flow of disinfected water with a lower need to add a new frit to the antibacterial column (see data in Table 3 in Example 1).

Examples of embodiments of the invention

Example 1

The ecological glass matrix in the exemplary embodiment contains the following amounts of the individual components (in parts by weight):

sodium oxide (Na2O) 10 lithium oxide (Li2O) 20 silica (SiO2) 40 boron oxide (B2O3) 30

In the specified composition (see protocol on antibacterial activity):

sodium oxide (Na2O) 10 lithium oxide (Li2O) 20.4 silica (SiO2) 39.8 boric oxide (B2O3) 29.8

The optimal granulometric glass matrix for sintering processes is 1 to 10 mm.

Glass uranium: glass sand TS 15 boric acid lithium carbonate granulated soda

Melting temperature range 1200 ± 100 ° C. Sintering temperatures range from 650 to 800 ° C.

The evaluation of the antibacterial activity of the glass matrix of the above composition is given in the following tables:

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Table 1 - Antibacterial efficacy

Escherichia col i CCM 4517 - contact times (inoculum concentration Cd = 5.7.10 ⁶ CFU / ml (log Cu = 6.8) 5 min 10 min 20 min | ÍÍÍČ | ÍÍ || (cfu / ml) lliii · Co - log C5 (cfu / ml) Co - log (cfu / ml) Co - log Vz.č.59 - -Lithaneborous glass with 20% L12O (S1O2 39.8%, Na ₂ 0 10%, B2O3 29.8%, Li ₂ O 20.4%), gran.l to 5 mm, 18.5. 2020 1.9.10 ⁶ 0.9 6.9.10 ³ 3.3 1.9.10 ² 5.2

Note: values are the average of three determinations

Table 2 - Evaluation of the effectiveness of antibacterial properties

Efficacy of antibacterial properties Antibacterial effect value (ie difference of logarithmic orders of bacterial concentrations) Weak 1 <A <2 Significant * 2 <A <3 Strong * A> 3

* Values and efficiency are taken from ČSN EN ISO 20743: 2014

Table 3 - Column flow test

100 ml volume flow through the column (min) Flow rate (ml / min) E. coli concentration (CFU / ml) Antibacterial efficacy (logical orders) 7 14.3 5.3.10 ⁶ 0.3 27 3.7 7/7/10 ⁴ 2.2 44 2.3 1,6.10 ² 4.3 65 1.5 <1 > 6.2 94 1.1 <1 > 6.2 120 0.8 <1 > 6.7

Note: values are the average of three determinations

Note: part of the system of a continuous system for water sanitation filled with the above-mentioned glass matrix is a special device for adjusting the pH of debacterized water to a pH level of 9.5 according to the relevant standard.

Example 2

The ecological glass matrix in the exemplary embodiment contains the following amounts of individual components (in mass, parts):

sodium oxide (Na2O) 5 lithium oxide (Li2O) 25 silica (S1O2) 50 boron oxide (B2O3) 20

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The optimal granulometric glass matrices, glass raw materials, melting temperature range and sintering temperatures are identical to Example No. 1.

As for the antibacterial activity of the glass matrix with the composition according to Example 2, a synergistic effect is also applied here, where lithium ions increase the antibacterial effect of boron ions. Therefore, the results are comparable to the results of Example 1.

Example 3

The ecological glass matrix in the exemplary embodiment contains the following amounts of the individual components (in parts by weight):

sodium oxide (Na20) 15 lithium oxide (L12O) 15 silica (S1O2) 40 boron oxide (B2O3) 30

The optimal granulometric glass matrices, glass raw materials, melting temperature range and sintering temperatures are identical to Example No. 1.

As for the antibacterial activity of the glass matrix with the composition according to Example 3, a synergistic effect is also applied here, where lithium ions increase the antibacterial effect of boron ions. Therefore, the results are comparable to the results of Example 1.

Claims (1)

PATENT CLAIMS An ecological glass matrix containing effective antibacterial ions, which is in the form of 5 free or sintered particles situated in blocks, which is intended for filling continuous water sanitation systems, characterized in that it has a particle granulometry of 1 to 10 mm and contains 5 up to 15 wt. parts of sodium oxide Na ₂ 0, 10 to 30 wt. parts of lithium oxide Li ₂ O, 20 to 40 wt. parts of boric oxide B ₂ O ₃ and 20 to 50 wt. parts of silica SiO ₂ .