Process for obtaining a carbon-mineral sorbent and process for demetallization of untreated wine by using thereof

Description:

The invention relates to the wine industry, in particular, to the processes of obtaining the carbonomineral sorbent and demetallizing the raw wines with the help of sorbents.

The process of obtaining sorbents is known using clay mineral raw material that activates with mineral acid solutions [1]. however, this process does not provide the required sorption capacity and selectivity of the sorbent thus obtained for the demetallization of raw wines.

Closer to the technical essence and the result obtained is the process of obtaining the carbonomineral sorbent, with the use of clay minerals processed in the process of clearing juices and wines, which includes their technical treatment, in order to carbonize the organic substances and to activate the carbonate [2]. According to this process, as a clay mineral, bentonite is used, as an activator, the water removed at dehydration up to 400 ° C and at dehydroxylation as a result of thermal processing up to 800 ° C. however, these sorbents are not effective for the demetallization of raw wines due to their low sorption capacity and selectivity to the impurities that contain metallic compounds.

For the demetalization of raw wines closer to the technical essence and the result obtained is the process that includes the use of sorbent, activated by processing in mineral acid solution [3]. For this, as sorbent, clay bentonite is used, and surface activation is carried out by processing in hydrochloric acid solution. however, this process is not quite effective, because the obtained sorbent does not possess high sorption capacity and selectivity regarding compounds of heavy metals such as iron, copper, etc. what is confined to raw wines.

The technical problem, which the present invention solves, is to reduce the process of obtaining the carbonomineral sorbent with high structural sorption characteristics due to the use of the wine wastes and the production conditions, as well as to increase the efficiency of the demetalization of the wines due to the high adsorption capacity. regarding heavy metal compounds, which are confined to raw wines.

The essence of the invention consists in obtaining the carbon-mineral sorbent based on the kiselgur used for the treatment of juices and wines through the technical processing, the carbonization of the organic substances adsorbed on the kiselgur and the activation of the carbonate. Technical processing is performed at 160 ° C for 2 hours and then carbonization and activation of the carbonate - at 420 ... 500 ° C for 1 ... 2 hours in an atmosphere of carbon dioxide, after which it is carried out cooling, crushing and processing with sulfuric or orthophosphoric acid solution of 10 ... 20%. Demetalization of raw wines using the obtained sorbent is carried out by the continuous method and includes their filtration 2 ... 3 times through the mentioned sorbent layer with a thickness of 20 ... 25 cm with a linear flow rate of 1.5 ... 2 , 5 m / hour, or by periodic method using the volumetric mass of the sorbent of 70 ... 100 g / dal of raw wines.

The processing of the carbonomineral sorbent in sulfuric acid solution or orthophosphoric acid solution leads to the formation of sulfo-groups or phosphate groups on its surface. This ensures the modification of the sorbent surface and the formation of ionic (cationic) exchange properties, while at the same time the selectivity and sorption capacity are renewed.

When processing raw wines by continuous method the filtration speed is low (1.5 ... 2.5 m / h) due to the sorption of macromolecules of the complexes of heavy metals, which provide selective sorption at the surface of the modified carbonomineral sorbent. the height of the filter layer (20 ... 25 cm) is chosen in such a way that it does not decrease the hydraulic resistance during the filtration.

The application of the proposed method allows to reduce the process of obtaining the carbon-sorbent sorbent and to increase the ecological purity of the technologies of the wine industry due to the use of used chiselgur and the exclusion of reagents, which leads to the formation of toxic sediments, and to increase the efficiency of the demetalization due to the increase of the sorbent capacity. adsorbent to heavy metal compounds, which are confined to raw wines.

The result of the invention consists in increasing the efficiency of the process of demetallization of the raw wines with the high content of heavy metal compounds due to the appearance of cationic exchange properties when changing the sorbent surface, increasing its selectivity and sorption capacity.

The carbon-mineral sorbent used after demetallization can be processed according to the conditions of the proposed process and used as a sorbent in various branches of industry, as an example, for waste water purification.

Example of carrying out the invention

Wastes containing used kiselgur, obtained when filtering and clearing wine products on a vacuum-rotary filter, with 70% humidity, are subjected to thermal processing at 155 ° C for 2 hours and then at 460 ° C for 1 hour. , 5 hours in an atmosphere of carbon dioxide. in this way, the carbonization of the organic substances is ensured by the formation of the carbon layer on the mineral matrix of the chiselgur and its surface activation. After cooling the product is crumbled to 0.5 ... 2.0 mm, the sorption and structure characteristics are studied, then used for the demetalization of raw wines.

The sorption and structure characteristics were studied according to the BET method. The research results are presented in table 1.

Table 1

<td rowspan="2">Sorbenfii</td><td colspan="4">Clues</td>

<td>Carbon content,%</td><td>Pore ​​radius, nm</td><td>Sulfur sump, m²/ g</td><td>Total pore volume, cm³/ g</td>

<td>According to the proposed procedure</td><td> 7,0...9,0</td><td> 5,0...6,0</td><td> 132</td><td> 0,25</td>

<td>According to the known procedure</td><td> 6,0</td><td> 2,5...3,0</td><td> 125</td><td> 0,22</td>

The preventive carbonomineral sorbent is processed with a solution of 15% sulfuric or orthophosphoric acid, the sediment is decanted, washed and under a slurry, it is directed to the demetallization process.

For demetallization, the wine containing 18.7 mg / 1 tier and 1.3 mg / 1 copper is used. Demetallization, as mentioned, is accomplished by the continuous method under dynamic conditions and by the periodic method. In the first case, the wine products are tree through the filter layer of the carbonomineral sorbent with the height of 22 cm and the filtration speed 2 m / hour 4 times. In the second case, the periodic method is used, using 85 g sorbent per 1 crude wine slab, then not clearing and separating the sediments.

For comparison, experiments are made with the use of the carbonomineral sorbent, obtained according to the conditions of the nearest solution.

Demetalization of raw wines, according to the proposed invention, is carried out with the use of the carbonomineral sorbent obtained by the proposed process, activated in the solution of mineral acid (the solution of

10 .. .20% of sulfuric and / or orthophosphoric acid) under dynamic conditions when passing through the filter layer of carbonomineral sorbent with a height of 20 ... 25 cm and a linear filtration rate of 1.5 ... 2.5 m / hour 3 ... 5 times or when processed by the periodic method, using 70 ... 100 g of sorbent per 1 slab of raw wine, then not clearing and separating the sediment.

The advantage of the invention is to increase the ecological purity of the wine industry due to the use of waste obtained in the wine production area and to exclude the use of chemical reagents, which results in the formation of toxic sediments, in the reduction of the expenses in obtaining the carbon-sorbent sorbent.

Kiselgur is a natural mineral, obtained from clay diatomite by special acid processing, due to which its sorption properties increase. However, obtained from this technology, kiselgur becomes a rather expensive product. The worn kiselgur, with the dispersion of 0.5 ... 1.0 mm, is an unused waste, which melts as a result of the filtering of the must on the rotary vacuum filter used in oenology. After processing the used ketchup, obtained under waste, confines up to 50 ... 70% of organic substances (yeasts, macromolecules of protein compounds, natural colorants, etc.) and accumulates in wineries.

Raw wines contain quantities of various heavy metals, especially tier. Its quantity can reach up to

20 .. .30 mg / 1 and above, increasing due to the contact of the wine products with the offal installations in the technological process, which leads to the deterioration of the qualitative indices and the organoleptic properties of the wine, decreases their stability, leads to metallic disorders and accumulation. sediments in the process of storage before being made, etc. at the same time the admissible amount of iron concentration in wines constitutes 5 .. .7 mg / 1 (for white wines) and 8.. .10 mg / 1 (for red wines). The heavy metals in these wines can be found not only under the free melt, but also under the melt of complex compounds with tartaric acid or other substances. Traditional demetallization technology is related to the use of the reagent - potassium hexacyanoferate (П), which leads to the formation of toxic sediments containing cyanide, including Berlin blue. The disposal of these sediments impurifies the environment, and their use is compound and scurnpous. Demethalation by sorption of wine products in exchange for reagent technology ensures the increased ecological purity of the industry.

The result is based on the fact that the use of used chisel, obtained under the waste sludge when filtering and clearing the wine products with absorption on it of organic substances, in the process of technical processing at 15O ... 16O ° C takes place the removal of moisture and the water is bound, and at 42O ... 45O ° C the carbonization of the organic compounds that make up the mineral matrix takes place and assigns them to a uniform surface. The presence of the carbon dioxide atmosphere in the carbonization process leads to the formation of the non-oxidized inert atmosphere and to the increase of the porosity and the sorption activity of the sorbent synthesized in this way. Due to this, the carbon-mineral sorbent is formed with micro- and mesoporous structure, with larger pore sizes, which include the hydrophilic properties of the inorganic mineral porous material and the hydrophobic properties of the activated carbon sorbent.

The chemical analysis of the metals of raw wines until and after processing is performed by the atomic adsorption method. The results of the experiments are presented in table 2.

Table 2

<td>Processing conditions and results</td><td>According to the proposed conditions</td><td>According to the conditions of the nearest solution</td>

<td>Technical processing - temperature, ° C</td><td> 150</td><td> 160</td>

<td>- time, hours</td><td> 2</td><td> 2</td>

<td>charring: - temperature, ° C</td><td> 450</td><td> 220</td>

<td>- time, hours</td><td> 2</td><td> 2</td>

<td>Acid activation: - sulfuric acid,%</td><td> 10</td><td></td>

<td>- orthophosphoric acid,%</td><td> 10</td><td> -</td>

<td>- hydrochloric acid,%</td><td> -</td><td> 10</td>

<td>Scrap content of metals when processing wine products, mg / 1: Continuous processing conditions: - The iron</td><td> 2,3</td><td> 11,8</td>

<td>- Copper</td><td>missing</td><td> 0,6</td>

<td>The processing regime by the periodic method: - The iron</td><td> 3,1</td><td> 11,5</td>

<td>- Copper</td><td> 0,1</td><td> 0,7</td>

According to the data obtained, the carbonomineral sorbent, obtained according to the proposed process, has much better sorption and structure characteristics compared to the known one. At the same time, the degree of demetallization of the wine products is 5-6 times higher than under the known conditions. Demetallization leads to increased stability of alcoholic beverages in metal disorders and contributes positively to their organoleptic qualities.