Removal of silicon from solution |
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IPC classes for russian patent Removal of silicon from solution (RU 2476379):
 Method of conducting electrolysis and apparatus for realising said method / 2475569
Method of conducting electrolysis employs at least two groups of electrodes which are electrically connected to a power supply, each having at least one pair of oppositely charged electrodes, wherein during electrolysis, an electrical circuit is switched, which enables alternate connection of groups of electrodes to the power supply, wherein during operation of the first group of electrodes, the second group and other groups are disconnected, after which the second group is connected to the power supply and the first and other groups are disconnected. The periodicity of alternate connection of groups of electrodes to the power supply is equal to 0.05-1.0 s. Also disclosed is an apparatus for conducting electrolysis, having an electrolysis cell and switching means, which enables alternate connection of the same groups of electrodes to the power supply while simultaneously disconnecting others.
 Unipolar-bipolar electrolytic cell to make mix of hydrogen with oxygen / 2475343
Invention relates to gas-flame processing of materials with hydrogen-oxygen mix, particularly, to electrolytic cells to this end. Electrolytic cell may be filter-press or box-type device. Note here that some electrodes of the cell are unipolar while some of them are bipolar electrodes. It consists of flat or shaped parallel electrodes with holes of slots making gas and electrolyte passages. Space between electrodes is filled with electrolyte while electric current is supplied to extreme electrodes. Said electrodes are interconnected by current conducting buses to make sets, two extreme of which comprise n+1 electrodes while other include 2n+1 electrodes, where n is natural number. Note here that central electrodes of every said set with 2n+1 electrodes are located between two adjacent sets while other 2n electrodes of this set are arranged at the center of gap between electrodes of adjacent sets with contact with said buses.
 Water electrolytic generator gate / 2474624
Proposed device is composed of vertical cylinder divided by two vertical baffles into three chambers. Branch pipes arranged concentrically one in another are attached from below to centre of both baffles. Lower chamber is partially filled with fluid. Note here that end of the branch pipe attached to lower baffle is immersed in lower chamber fluid while branch pipe attached to upper baffle extends through medium chamber and into the branch pipe attached to lower baffle and either does not reach fluid surface in outer branch pipe or terminates several centimetres below fluid surface. Lower and medium chambers are communicated via long tube.
 Hydrogen generator / 2473716
Hydrogen generator comprises casing accommodating runs of plates separated by gaps to form impermeable cells. Note here the plate making the first wall of every cell is made from more noble material than plate making second wall of this cell. Note also that fist plate in runs makes anode to be connected to power supply. Note also that last plate in runs makes cathode to be connected to power supply. Inlet of every cell allows electrolyte inflow into cell while outlet of every cell allows electrolyte and hydrogen gas efflux from cell.
Hydrogen generator / 2473716
Hydrogen generator comprises casing accommodating runs of plates separated by gaps to form impermeable cells. Note here the plate making the first wall of every cell is made from more noble material than plate making second wall of this cell. Note also that fist plate in runs makes anode to be connected to power supply. Note also that last plate in runs makes cathode to be connected to power supply. Inlet of every cell allows electrolyte inflow into cell while outlet of every cell allows electrolyte and hydrogen gas efflux from cell.
 Novel highly stable aqueous solution, nano-coated electrode for preparing said solution and method of making said electrode / 2472713
Invention relates to disinfectant compositions and specifically to a highly stable acidic aqueous solution, a method and apparatus for production thereof. The solution is prepared using a fluid medium treatment apparatus having at least one chamber (7), at least one anode (4) and at least one cathode (3) inside the chamber (7). The anode (4) and the cathode (3) are at least in part made from a first metallic material. At least one of said at least one cathode (3) and anode (4) have a coating with nanoparticles (5) of one or more metals.
 Electrolysis cell for producing chlorine / 2471891
In an electrolysis cell for producing chlorine, bipolar electrode elements are made from a bimetallic sheet (steel+titanium); frames of bipolar chambers are made from shaped tubes; anode and bipolar chambers are made from a bimetallic sheet which is made by welding sheets with insert bimetallic (steel+titanium) elements; the anode and the cathode chambers are equipped with built-in heat exchangers, one part of which is formed by placing shortened metallic separating strips inside the chambers and hermetic sealing of the outer surface of the chambers with a metal sheet; the second part is formed by making supporting frames of the chambers hollow, which enables to use water cooling.
 Electrocatalytic method for synthesis of hydrocarbons and alcohols based on plant material / 2471890
Method is realised in a diaphragmless cell which is equipped with an anode and a cathode, in the medium of methyl or ethyl alcohol in the presence of a base, as a result which there is direct electrooxidation of said acids, where the anode used is graphite, pyrographite, Pt-Ir metallurgical alloy, or nanoparticles of a Pt-Ir alloy in amount of 0.1-1.0 mg/cm-2 which are deposited on the surface of glass carbon, and the cathode used is a stainless steel cathode.
 Method for obtaining ionic silver solution / 2471018
Metallic silver is diluted in distilled water till electrolyte is formed. After electrolyte is formed as a result of anodic silver oxidation and self-dilution of oxide, dilution process is interrupted, electrolyte is drained and magnetised by passing it through a glass tube going through magnetic field of constant magnet. Then, at weak mixing of the solution, dilution process of metallic silver is continued till hardly transparent black suspension is formed; after that, the process is stopped. Settled concentrate is separated; in addition, clean electrolyte is magnetised and again brought into circulation, and deposit of crystalline hydrate of silver oxide (1) is used in order to obtain water solution of ionic silver, at which crystalline hydrate is diluted in water, magnetised in magnetic field, filtered and drained to glass bottles to be stored.
 Method of producing high-purity lithium hydroxide and hydrochloric acid / 2470861
Invention can be used in chemical industry to produce crystalline monohydrate of lithium hydroxide which is used in accumulator batteries, and lithium carbonate. The method of producing crystals of monohydrate of lithium hydroxide and hydrochloric acid involves purifying lithium-containing brine via ion exchange in order to reduce concentration of calcium and magnesium ions. The brine undergoes electrolysis to obtain lithium hydroxide solution containing less than 150 ppb of the total amount of calcium and magnesium to obtain gaseous chlorine and hydrogen as by-products. Hydrochloric acid is obtained by burning the obtained chlorine gas with excess hydrogen. Lithium hydroxide solution is concentrated and crystallised to obtain crystals of a monohydrate of lithium hydroxide.
 Method of complex purification of aqueous solutions of metal chlorides from iron and sulphate ion impurities / 2373140
Aqueous solutions of metal chlorides are successively treated with an oxidant and a calcium chloride source and/or barium chloride source with molar ratio of oxidant and divalent iron ions in the range (0.95-1.90):1.0 and molar ratio of calcium chloride and/or barium chloride and sulphate ions in the range (0.9-1.1):1.0 with subsequent coprecipitation of a hydrate of iron (III) oxide and calcium sulphate and/or barium sulphate at pH of the reaction medium between 5.0 and 9.5 and separation of the liquid and solid phase of the suspension.
 Method of producing brine for electrolysis / 2347746
Present invention can be used for obtaining aqueous saturated solutions of alkali metal halides, which are used in the production of chlorine and alkali from electrolysis. The method of producing aqueous saturated brine of alkali metal halides involves underground dissolving of salt deposits with simultaneous purification of brine in the brine production well. Purification from toxic impurities - calcium and magnesium compounds is done using spent brine of a halide of the corresponding metal as the solvent, obtained from an electrolysis unit with pH 9-12. The brine from the well is then purified from calcium and magnesium compounds.
Method of sulphate-ion absorption in metal chloride aqueous solutions / 2334678
Method of sulphate-ion absorption in metal chloride aqueous solutions by reaction of sulphate-ions with calcium chloride at higher temperature with following precipitation and removal of solid calcium sulphate. Calcium chloride source is production residue of calcium chloride, containing calcium chloride within 15-38 mass % and water-insoluble substances within 2-55% of residue weight. Production residue of calcium chloride is coagulated sludge chloride calcium suspension of mass fraction of calcium chloride within 25-38% and mass fraction of water-insoluble substances within 2-14 % or filter cake, produced by filtering of sludge chloride calcium suspension and containing calcium chloride within 15-30 mass % and water-insoluble substances within 20-55 mass %, or mixed specified sludge suspensions and specified filter cake.
How considine and purification of natural underground brine from impurity ions of calcium and magnesium / 2230029
The invention relates to electrochemical industry for the production of purified brine (sodium chloride solution) for the electrolytic production of chlorine and sodium hydroxide
 The purification method of solution of sodium chloride / 2179952
The invention relates to the chemical industry, to methods of cleaning solution of sodium chloride soda-caustic method from the salts of calcium and magnesium
 The purification method of solution of sodium chloride / 2176616
The invention relates to methods of cleaning solutions of chlorides of alkali metals salts of calcium and magnesium
 The purification method of solution of sodium chloride / 2173298
The invention relates to the chemical industry, to methods of cleaning solutions of chlorides of alkali metals salts of calcium and magnesium
 The purification method of solution of sodium chloride / 2169116
The invention relates to a technology for purifying brine of sodium chloride soda-caustic method for the production of chlorine and caustic soda diaphragm method
 The method of producing carbonate of an alkali metal, a method of producing sodium carbonate, brine purification method / 2099286
The invention relates to the production of carbonates of alkali metals, in particular sodium carbonate
Method of sulphate-ion absorption in metal chloride aqueous solutions / 2334678
Method of sulphate-ion absorption in metal chloride aqueous solutions by reaction of sulphate-ions with calcium chloride at higher temperature with following precipitation and removal of solid calcium sulphate. Calcium chloride source is production residue of calcium chloride, containing calcium chloride within 15-38 mass % and water-insoluble substances within 2-55% of residue weight. Production residue of calcium chloride is coagulated sludge chloride calcium suspension of mass fraction of calcium chloride within 25-38% and mass fraction of water-insoluble substances within 2-14 % or filter cake, produced by filtering of sludge chloride calcium suspension and containing calcium chloride within 15-30 mass % and water-insoluble substances within 20-55 mass %, or mixed specified sludge suspensions and specified filter cake.
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FIELD: chemistry. SUBSTANCE: invention can be used in chemical industry. In order to remove silicon compounds from water NaCl brines, first, pH lower than 3 is created with hydrochloric acid in weak brine. Iron (III) chloride or other trivalent iron compounds are added to acidified brine. Prepared brine is continuously introduced into mixing dissolution reactor, in which in addition to brine undissolved salt is placed. Fresh salt is added into reactor periodically in portions. Formed concentrated brine is introduced into mixing buffer tank. PH from 5 to 8 is supported in buffer tank. From buffer tank flow of concentrated brine is continuously withdrawn and filtered, filtrate is discharged. Device for removal of silicon compounds from solution contains reactor of salt dissolution, mixing device in it, charging device for supply of salt into reactor, feeding point for supply of weak brine into reactor, feeding points for supply of hydrochloric acid and iron (III) chloride into line of weak brine supply, buffer tank for concentrated brine, mixing device in buffer tank, hydrodynamic connection between dissolution reactor and buffer tank and discharging device for filter cake, discharge channel and transport mechanism for delivery of concentrated brine from buffer tank into filter. EFFECT: invention makes it possible to increase rate and simplify process of purification of brine, intended for electrolysis. 15 cl, 2 dwg
The invention relates to method and also appropriate for device for removing silicon compounds from the brine, which is suitable for electrolysis. The silicon can be removed as an ancillary element together with rock salt or sodium chloride, which is salt deposits, or sea salt, usually in the form of silicic acid. The salt solution it is in a Monomeric or amorphous form or in the form of polysilicon acid, and also in the form of agglomerates and interferes with the process of electrolysis. According to the traditional prior art, as described, for example, in the document US 4274929 A silicon remove that add magnesium chloride and raise the pH. By requiring a lot of time way with agitator-separator can separate the precipitated silica and remove from the brine. In the document US 4946565 is also considered A method of removing silicon compounds from the brine. Here are Fe (II) or Fe (III), which form a complex with contained in the brine impurities of silicon, deposited in the settling tank. Here also work at alkaline pH values. Similar is the case in DE 2816772 A1. There is sought protection to a chemical reagent, which may be sodium hydroxide, sodium carbonate, calcium hydroxide, calcium chloride, barium chloride, barium carbonate and/or chloride is Eliza (II), add to precipitate and separate the impurities from the solution and simultaneously enter into a solution of suspended impurities, which are present together with the reagent, thus, silicon dioxide is deposited together with impurities. At the time of deposition of the oxide of silicon dioxide with impurities establish a pH from 8 to 11. The disadvantage of the above method is that it requires a lot of cost, and the deposition of the corresponding silicates should be carried out at an alkaline pH, but not in an acidic environment, as may be given in the subsequent electrolysis process. Therefore, the present invention is to develop a fast process, which is a simplified and improved method of action based on the conventional technology. The next task of the invention is to create a device that cost can be integrated into an existing installation of chlorine electrolysis. The invention solves this problem by a method of removing silicon compounds from aqueous NaCl brines, in which: - first in a weak solution of hydrochloric acid to establish a pH below 3, in this weak acidified brine add ferric chloride (III) or other trivalent ions of iron, - prepared so weak brine is continuously injected into the stirred reactor dissolution, in which the brine n who have also undissolved salt, in the reactor dissolving portions periodically added fresh salt, educated concentrated brine is introduced into the buffer tank mix, this buffer tank is kept at pH values from 5 to 8, from this buffer tank is continuously withdrawn stream of concentrated brine and filtered, and filtration of the precipitate, which contains added iron and silicon, is unloaded. In one embodiment, method mixed with chloride of iron (III) weak brine at pH values from 1 to 2 is introduced into the dissolution reactor. In addition, the dissolution reactor may also contain additional feeding point for feeding iron chloride (III) or other trivalent iron ions. For example, you can first enter 0,3 h/million iron ions in weak brine, and then optionally add 1 tsp per million of iron ions in the dissolution reactor. In the following embodiments of the method can be such that the reactor dissolution, or buffer tank, or both were made with air jet nozzles for mixing. In the following embodiment, the method may provide that unloaded filter the precipitate, which contains added iron and silicon, free from brine in a filter press, and the brine return in the process. The invention solves sleduushuu the task and the device for implementing the described method, contains: the reactor dissolved salt, - mixing device in the reactor dissolution, - boot device for the periodic supply of salt in the reactor dissolution, the feeding point to enter a weak brine in the reactor dissolution, - the point of supply to the input of hydrochloric acid and iron chloride (III) or other trivalent iron ions in the supply line of weak brine, buffer tank for the concentrated brine, - mixing device in the buffer tank, - hydrodynamic connection between the reactor dilution and buffer tank, filter by edition of concentrated brine and unloading device for filter cake, - the discharge channel and a transport mechanism for holding the concentrated brine from the buffer tank to the filter. In embodiments of the method provides that the reactor dilution and buffer tank formed as a single unit, which is divided through the bypass device. This uniform design of the reactor dilution and buffer tank is preferably designed as a tub. Submission weak brine in the reactor dissolution is advisable introduced through line located at the bottom of the reactor dissolution, which have directed up the holes in the form of channels or nozzles. This will speed up restore is based on the ability of the device. In addition, the air jet nozzle or nozzle for brine should be located and oriented in the dissolution reactor thus, in order to ensure the circulation flow around the vertical axis. Further method steps according to the invention more illustrated examples. Figure 1 shows a block diagram of a method with the reactor dilution and buffer tank, boot devices, and followed by filtration of the concentrated brine. Weak brine 1 with a salt concentration of 220 kg/m3hydrochloric acid 2 is set at pH 2. Then, depending on the concentration of silicon in the fresh salt, acidified with a weak brine add in a few hours/million of ferric chloride (III) 3. It is important that the pH was quite low, as iron chloride (III) is stable only at pH below 4. If supplied a weak brine already has a pH below 4, further acidification can be made by adding iron chloride (III). Acidified and equipped with iron chloride (III) weak brine is introduced into the dissolution reactor 4, which usually is always a residue of undissolved salt. At intervals of about 20 minutes in the dissolution reactor 4 feeder 5, which may be a bucket truck, covered a portion of fresh salt. It is important that the button this filing occurred within a short period of time, that is, for example, once a full bucket. In this fresh salt along with sodium chloride as the main component are also typical impurities, for example the already mentioned silicon and compounds of magnesium and sodium carbonate, and sodium hydroxide, which acts as a strong base. As a consequence, within a few minutes of time after addition of fresh salt the pH of weak brine in the reactor dissolving 4 changes rapidly in the process of dissolution from 2 to 11, then for the next few minutes it falls back to the initial pH value of 2. As soon as it reached pH 4, iron chloride (III) will begin to decompose and will react with the formation of iron hydroxide, which falls out of solution. Purely visually, this change is dissolved, greenish and transparent chloride iron (III) hydroxide iron makes itself felt by the fact that the brine slightly stained in brown color. Precipitated precipitated iron hydroxide binds on itself silicic acid and other compounds of silicon. It is assumed that this may be the adsorption process, but the invention is not bound by loyalty to this assumption. Because of the deposition reaction of hydroxide of iron, it is important to add salt occurred quickly, as mixed with chloride of iron (III) weak brine had the t little time to evenly distributed in the dissolution reactor 4, and only if the uniform distribution was achieved, you can take existing silicon in the whole volume of the reactor dissolution 4. For this reason, it may also make sense to facilitate rapid distribution of incoming weak brine efficient mixing system. From the reactor dissolving 4 concentrated brine flows in the salt content of approximately 300 kg/m3through the bypass device 6 in the buffer tank 7, the size of which is designed so that with the reliability to avoid pH values at which the hydroxide of iron again could react to iron chloride (III). In practice proved to be effective region of pH 5 to 8, above pH 9 was observed that precipitated together silicon again goes into solution. Buffer tank 7 should also mixed, as in some periods of time of dissolution of the concentrated brine flows from the reactor dissolving 4 in the buffer tank 7 at pH values below 4. At these time intervals in the buffer tank 7 is the reaction of iron deposition and simultaneous binding of silicon, and the equilibrium distribution by volume should be provided in the buffer tank 7. From the buffer tank 7 concentrated brine 9 is withdrawn by a pump 8 for brine and filtered by the filter 10. Filtered the precipitate hydrated 11 consists mainly of iron hydroxide and silicic acid. This sediment filter 11 can be pressed in a filter press (not shown) and regenerated there concentrated brine can be returned to the buffer tank. Purified concentrated brine 12 is essentially not contain compounds of iron and silicon and may, if necessary after additional processing steps can be used for chlorine (NaCl) electrolysis. Further, the design of the device according to the invention is illustrated by Fig. 2, which shows the reactor dilution and buffer tank with equipment. The dissolution reactor 4 and the buffer tank 7 are combined in the same tank, which separates the two tank overflow device 6. Tub is open at the top. For weak brine (1) provides the supply line, to which is also attached submission for hydrochloric acid 2 and iron chloride (III), which are located directly at the bottom of the reactor dissolution or immediately above the distributor 15 weak brine. The distributor 15 weak brine consists of closed on one end of the pipe in which the holes 16. Holes 16 are vertically but can be oriented so that they are supportive of the circulating current in the dissolution reactor 4. The dissolution reactor 4 as a mixing device contains an air jet stream or a stream with brine 13, which is connected with Vodohod the koi or other device to increase the pressure and includes a nozzle, from which the air may come out with a high speed below the liquid surface. Buffer tank 7 also has such an air jet or stream of brine 14. In addition, it contains the outlet 17 for concentrated brine, which is connected to the pump 8 to the brine feed the concentrated brine 9 to the filter 10, which contains the edition purified concentrated brine 12 and release for filter cake 11. The list of positions for links 1 weak brine 2 hydrochloric acid 3 chloride iron (III) 4 reactor dissolution 5 feeder 6 the bypass device 7 buffer tank 8 pump for brine 9 concentrated brine 10 filter 11 sediment filter 12 purified concentrated brine 13 jet mixing device of the reactor dissolution 14 jet mixing device buffer tank 15 allocator weak brine 16 holes 17 removal of concentrated brine 1. Method of removing silicon compounds from aqueous NaCl brines, which 2. The method according to claim 1, characterized in that mixed with ferric chloride(III) or other trivalent iron ions weak brine at a pH value of from 1 to 2 is introduced into the reactor dissolution. 3. The method according to claim 1 or 2, characterized in that the reactor is dissolved add the ferric chloride(III) or ferric ions. 4. The method according to claim 1 or 2, characterized in that the reactor dissolution stirring is carried out by the jet stream. 5. The method according to claim 3, characterized in that the reactor dissolution stirring is carried out by the jet stream. 6. The method according to one of claims 1, 2 or 5, characterized in that the buffer tank stirring is carried out by the jet stream. 7. The method according to claim 3, characterized in that the buffer tank stirring is carried out by the jet stream. 8. The method according to one of claims 1, 2, 5 or 7, characterized in that the unloaded fil is Navalny sediment which contains added iron and silicon, free from the brine in the filter press. 9. The method according to claim 3, characterized in that the discharged filter cake, which contains added iron and silicon, free from the brine in the filter press. 10. The device for implementing the method according to claim 1, including 11. The device according to claim 10, characterized in that the reactor dilution and buffer tank to form a single structure, which is divided by-pass device. 12. The device according to claim 11, distinguish what Eesa fact, the single design of the reactor dilution and buffer tank designed as a tub. 13. Device according to one of p-12, characterized in that the flow of weak solution in the dissolution reactor is inserted through the bottom of the reactor dilution lines that have directed up the holes in the form of channels or nozzles. 14. Device according to one of p-12, characterized in that the reactor dilution jet mixing device is located and designed so that you could get the circulation flow around the vertical axis. 15. The device according to item 13, characterized in that the reactor dilution jet mixing device is located and designed so that you could get the circulation flow around the vertical axis.
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