Method of producing anticorrosive pigment

FIELD: chemistry.

SUBSTANCE: anticorrosive pigment is obtained from a mixture of pigment components of oxygen-containing metal compounds. The method of producing pigment involves heat treatment of the mixture and grinding the heat treated product. The anticorrosive pigment is produced from a suspension of its components. The anticorrosive pigment additionally contains a pigment inhibitor-component which is a waste from neutralisation baths of machinery production, with the ratio of components galvanic sludge: inhibitor-component equal to 1:1 (on iron and calcium oxides) based on calcium contained in the galvanic sludge.

EFFECT: obtaining cheap highly resistant anticorrosive pigments with a ferrite structure, obtained from galvanic sludge, and wide field of their use.

2 ex, 1 tbl, 1 dwg

 

The invention relates to the production of anticorrosive pigments that can be used for the preparation of conservation of lubricants. You know getting releaxing inorganic pigments industrial waste during the process of calcination of iron precipitation electrochemical treatment of wastewater of electroplating [A.S. USSR N1370124, CL SS 1/24, 1988]. The disadvantage of this method of obtaining pigments is the oxidation of compounds of trivalent chromium to chromium, which significantly narrows down the possible applications of such pigments. In addition, electrocoagulation cleaning galvanostatic implemented only on a small number of industrial production (8-12% of the total number of electroplating plants), whereas in most plants use chemical treatment of electroplating wastes precipitation with calcium hydroxide.

Closest to the proposed method of obtaining anti-corrosion pigment is a method of obtaining a pigment of the components of the pigment oxygen-containing metal compounds, including heat treatment of the mixture and grinding the heat-treated product. [RF patent N2055086, CL SS 1/28, SW 33/14, 1996]. The disadvantage of this method is the low corrosion resistance of the obtained pigments, representing a mixture of metal oxides.

The task of izaberete the Oia is getting cheap, durable, anti-corrosive pigments ferritic structure, derived from galvanostatic (GSH), and expanding the scope of their application.

This task is solved by the creation of an anticorrosive pigment having high anti-corrosion properties To increase the corrosion resistance properties of the pigments is added pigment component-inhibitor (CI), which is a departure after baths neutralization of machine-building productions, containing mainly calcium hydroxide CA(Oh)2. This waste has a fine structure and unlike other inhibiting substances particles of calcium hydroxide are in the form of flakes, so the pigments based on it have along with inhibiting and barrier effect.

The task is also solved by a method of obtaining anti-corrosive pigment of the components of the oxygen-containing metal compounds, including heat treatment of the mixture and grinding the heat-treated product, in which the mixture components are oxygen-containing suspension components suspension of sludge electrochemical treatment of wastewater of electroplating and suspension of the pigment component inhibitor (KI) - departure after baths neutralization of machine-building productions, containing mainly calcium hydroxide CA(Oh)2in the ratio is AI NG:KEY 1:1 (oxides of iron and calcium) with regard to calcium, contained in GSH. Economically justified, because the production initially after wastewater treatment formed suspension sludge having a moisture content up to 70%to keep it in further processing, the company has advanced it to dry to a moisture content of less than 5%, which leads to increased energy consumption and, as a consequence, the cost of raw materials. The proposed method allows to process sludge with high water content, namely up to 70%.

Suspension GSH and suspension KI thoroughly mixed in an amount such that the observed 1:1 ratio for ions of iron and calcium. The resulting suspension is filtered, and the residue is dried in a drying Cabinet. The mixture is mechanically fray and placed in ceramic crucibles. Then the crucible with the charge is placed in a preheated muffle furnace, where calcined at 900°C for one hour. After the annealing crucible is transferred into a desiccator for cooling. The grinding of the obtained pigment is carried out mechanically.

The invention consists in the creation of technology for durable, anti-corrosive pigments brown palette of colors based on the recycling of electroplating waste and baths neutralization engineering companies, which currently are not implemented and are discharged into a dump, polluting the environment.

p> The invention permits the processing of raw materials (galvanoscope) obtaining highly resistant anticorrosive pigments with good quality - hiding power, stability, heat resistance, providing a broad range of applications.

Additionally, to determine antikorrozionnym properties of the obtained pigments were determined currents corrosion potentiometric method. This was filmed polarization curves in anodic and cathodic areas. Similar curves were constructed for the industrial design of the pigment (THE No. 82.3.011-99). Polarization curves are used to determine corrosion rate, as they give valuable information about the nature of the corrosion process and allow us to calculate the absolute speed. Since the rate of the electrode process is controlled by the speed of the electrochemical reaction, i.e. the rate of discharge of hydrogen ions or ionization of metal, in semi-logarithmic coordinates, the dependence of the potential on the logarithm of the current density is expressed by a straight line. Extrapolating the straight stretches of these polarization curves, we can determine the values of the corrosion currents (so-called graphical method).

The obtained curves are presented in figure.

Example 1. The electrochemical galvanic sludge wastewater treatment galvanize the who manufacture washed with 90 ml of water, heated to a temperature of 50°C, then filtered, and the residue is dried in a drying Cabinet. The obtained dried sludge mechanically fray and placed in a ceramic crucible. Then the crucible with the charge is placed in a preheated muffle furnace, where calcined at 900°C for one hour. After annealing the crucible is transferred into a desiccator for cooling. The grinding of the obtained pigment is carried out mechanically to a particle size not exceeding 10 microns.

Example 2. In the suspension of galvanostatic electrochemical treatment of wastewater of electroplating (GSH) in addition impose a suspension of the pigment component inhibitor (KI) - departure after baths neutralization of machine-building productions, containing mainly calcium hydroxide CA(Oh)2in the ratio of GSH:KEY 1:1 (oxides of iron and calcium) subject to the calcium contained in GSH, carefully mix the resulting suspension is filtered, and the residue is dried in a drying Cabinet. The mixture is mechanically fray and placed in ceramic crucibles. Then the crucible with the charge is placed in a preheated muffle furnace, where calcined at 900°C for one hour. After the annealing crucible is transferred into a desiccator to cool.

The values of the currents corrosion:

for anticorrosive pigment in the slurry GSH:KI I=15,1 µa;

for GSH I=50 µa.

Thus, the corrosion rate for anticorrosion pigment based on the suspension of the General staff, where the additionally introduced pigment component-inhibitor (KI)is several times lower than for anticorrosion pigment based on the dry GSH. When using an anticorrosive pigment according to example 2, the potential is shifted in the positive direction by about 20 mV. This is due to the dual mechanism of action of ferrites on the basis of galvanic sludge and waste after baths neutralization of machine building production, which is associated with the formation of the optimal number of hydroxyl ions, sufficient for the passivation of the metal electrode.

Thus, the claimed technical solution allows you to develop a way to obtain cheap antikorrozionnym pigments derived from suspension galvanostatic (GSH) and suspension of the pigment component inhibitor (CI), to expand the scope of their application compared with the known solutions.

Table
Properties of the resulting anti-corrosive pigments
IndicatorsThe pigment of GSH (example 1)The pigment suspension GSH:KI (1:1) (example 2)P is gment in accordance with specifications No. 82.3.011-99 Test methods
The content of water-soluble compounds, not more than %0,410,42paragraph 4.7 on THE No. 82.3.011-99
The content of substances insoluble in hydrochloric acid, %183030-40item 4.9 on THE No. 82.3.011-99
The cash portion of the iron compounds in terms of Fe2O3, %675735-70item 4.4 on THE No. 82.3.011-99
The oil absorption, g/100 g pigment, no more than22,9%29,5%40GOST 21119.8-75 and paragraph 4.12 on THE No. 82.3.011-99
pH8,5107-11GOST 21119.4-75 and paragraph 4.10 for THE No. 82.3.011-99
The residue after wet sieving sieve 0,063%, no more than0,970,38 1GOST 21119.4-75 and paragraph 4.11 on THE No. 82.3.011-99
Hiding power g/m2not more than281930GOST 8784-75 and paragraph 4.13 on THE No. 82.3.011-99
ColorbrownbrownWithin tolerances approved color sampleGOST 16873-78-75 and section 4.3 for THE No. 82.3.011-99
Current corrosion, MCA5015,1not rules.GOST 9.602-89 and 9.602-2005

The method of obtaining anti-corrosive pigment of a mixture comprising the pigment oxygen-containing metal compounds, including heat treatment of this mixture and grinding the heat-treated product, wherein it is produced from a suspension of these components and further comprises a pigment component-inhibitor, represents a departure after baths neutralization of machine building production in the following ratio of the components of the galvanic sludge:component-inhibitor - 1:1 (oxides of iron and calcium) subject to the calcium contained in galvanos the AME.



 

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FIELD: chemistry.

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23 cl, 33 dwg, 28 ex

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22 cl, 4 tbl

FIELD: textiles, paper.

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35 cl, 1 dwg

FIELD: chemistry.

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40 cl, 2 tbl, 4 ex

FIELD: chemistry.

SUBSTANCE: invention can be used in chemical industry. The method of producing jointly ground calcium carbonate material, which contains ground calcium carbonate (GCC) material and precipitated calcium carbonate (PCC) comprises the following steps: a) obtaining at least one calcium carbonate material, optionally, in form of an aqueous suspension; b) combined grinding of GCC and PCC, optionally, with at least another mineral material which is selected from talc, clay, Al2O3, TiO2 or mixtures thereof; c) optional sieving and/or concentration of the jointly ground calcium carbonate obtained at step (b); d) optional drying of the jointly ground calcium carbonate material obtained at step (b) or (c). The fraction of particles of the obtained material with size smaller than 1 mcm is greater than 80%, preferably greater than 85%, more preferably greater than 90% and even more preferably greater than 95%. BET specific surface area is less than 25 m2/g.

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44 cl, 2 tbl, 5 ex

FIELD: chemistry.

SUBSTANCE: present inventions relate to a method of producing precipitated calcium carbonate (PCC) and the design of a low-power reactor system for realising the method such that, the amount of dry residues in the PCC product can be increased to 35% or more without a dehydration step. The disclosed method involves steps for bringing calcium hydroxide into contact with a carbon dioxide-containing gas in parallel or two or more separate reaction vessels in order to form calcium carbonate. Calcium oxide, lime or dry calcium hydroxide or a combination of any of the three components are also added to a portion of the obtained mixture of calcium hydroxide and calcium carbonate. When used in the production of PCC, the reactor system has at least one reactor vessel with an optional water inlet and gas inlet and at least one recirculation reservoir for inlet of components and optional water inlet.

EFFECT: use of the disclosed method and device ensure efficient and economical production of PCC with a given structure and high content of dry residues.

21 cl, 8 dwg, 9 ex

FIELD: chemical and pulp-and-paper industry.

SUBSTANCE: aqueous suspension of at least one filler or mineral contains natural carbonate, polymeric dispersing agent as stabilizer of suspension viscosity, product of natural carbonate treatment with gaseous CO2, and product of natural carbonate reaction with at least one medium or strong H3O+-donors, has pH more than 7.5 at 200C. As natural carbonate suspension contains calcium carbonate (e.g., marble, calcite, carbonate-containing dolomite, chalk, ore mixtures thereof with talcum, and/or TiO2, MgO, or other minerals inert to H3O+-donors). As H3O+-donors suspension contains H2SO3, HSO

-4
, H3PO4, oxalic acid or mixtures thereof in molar ratio to carbonate of 0.1-2. Used carbon dioxide under pressure of 0.05-5 bar may be added from outside, recycled or obtained by continuous H3O+-donors addition. Treatment with H3O+-donors and gaseous CO2 may be carriedout simultaneously or separately, wherein in the last case temperature and time of respective stages are 5-900C and 1-5 h. Claimed suspension is dried to obtain colorant. Colorant has BET specific surface of 5-200 m2/g according to ISO 9277 and mean grain size measured by sedimentation method of 0.1-50 mum. Colorants are used in compositions, as agent for paper lamination, for paper pulp filling, coloration, and board production. Obtained paper is useful in numeric and ink-jet printing.

EFFECT: paper with decreased mass at constant surface.

33 cl, 1 dwg, 2 tbl, 8 ex

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