KR100480454B1 - Metod of manufacturing for Aluminium silicate soltes - Google Patents

Abstract

The present invention relates to a method for producing a basic aluminum silicate, using a aluminum chloride (aluminum dross) that is indispensable in the production of aluminum ingots produced in a large amount (about 10,000 ~ 20,000 tons / month) of water treatment agent production in Korea It manufactures [PACS (Poly Aluminum Chloric Silicate)] and polysulfate silicate [PASS (Poly Aluminum Sulfuric Silicate)], which not only contributes to the cost and environmental pollution caused by the disposal of aluminum ash, but also significantly lowers the cost of water treatment agent manufacturing and greatly reduces the treatment effect. To improve.

Description

     Method of manufacturing basic aluminum silicate {Metod of manufacturing for Aluminum silicate soltes}

The present invention relates to a method for producing basic aluminum silicate using aluminum as the main raw material. In detail, the aluminum ash is dissolved to form a precipitate with sodium silicate, which is dissolved with sulfuric acid or hydrochloric acid to disperse aluminum sulfate ( The present invention relates to a method for producing a basic aluminum silicate from an aluminum material (Aluminum Dross) for producing PASS) or aluminum chloride silicate (PACS).

Aluminum dross refers to slug which is produced when molten aluminum metal or scrap is melted in aluminum ingot or sash manufacturing plant to make aluminum metal in a lump state. Among them, 20 to 40% of Al metal is contained. It can be dissolved in caustic soda and used as raw material for water treatment agent or detergent, pharmaceuticals, etc.In Korea, aluminum ingot manufacturer is re-melting aluminum dross to recover aluminum metal. Aluminum metal remains after reprocessing. By using this, aluminum hydroxide, which is a raw material of the water treatment agent, can be made, and a water treatment agent can be prepared directly. Considering this point (manufacturing of water treatment agent), PACS or PASS was directly produced from aluminum material without using aluminum hydroxide manufacturing process and used for water treatment agent.

Main components of aluminum dross are aluminum oxide (Al ₂ O ₃ : 30 ~ 50%) and metal aluminum (Al: 20 ~ 40%). Others except trace amounts of Si, It contains Fe, Ca, k, Na, etc. (0.1 ~ 5%)

The component analysis table is as follows, but this depends on the part of the sampling and also varies depending on the establishment.

ingredient Al ₂ O ₃ MgO Na ₂ O SiO ₂ Cl K ₂ O CaO Fe ₂ O ₃ heavy metal Unit (wt%) 76.99 6.11 4.09 3.77 1.81 1.27 1.09 0.51 N, D

 The table above is the analytical value of a sample of 35% Al metal.

Conventional methods use aluminum hydroxide, an aluminum compound, to produce aluminum sulfate, polyaluminum chloride, and other water treatment agents with a solution of sodium hydroxide dissolved in caustic soda and basicity with sodium silicate. By importing bauxite, which is not produced in Korea, it is decomposed into high concentration caustic soda at high temperature and high pressure, and then used after being filtered. Therefore, expenses related to foreign currency outflow, rising production cost, and disposal of by-product red mud Burden and environmental pollution are occurring.

Bauxite contains about 60% of aluminum oxide and about 35% of domestic kaolin is used as raw material, but Kaolin contains a large amount of insoluble SiO ₂ (45%). It is contained in the situation that does not have a way to use it is not used.

The purpose of dissolving an aluminum compound with sulfuric acid or hydrochloric acid to increase the basicity is to increase the basicity to reduce the consumption of alkali (caustic soda or hydrated lime), which is a neutralizing agent, and to increase the degree of polymerization of the inorganic coagulant.

In short, the conventional method

                                      High temperature, high pressure decomposition

 1.Bauxite + Caustic Soda Solution ----------- → Soda Alkaline Solution → Filtration → Hydrolysis or Seeding → Filtration → Aluminum Hydroxide

  ㆍ To prepare water treatment agent, aluminum hydroxide is decomposed into acid again.

   Aluminum hydroxide + hydrochloric acid or sulfuric acid → aluminum chloride, aluminum sulfate

1-1 Preparation of high basic water treatment agent

A water treatment agent having a high basicity is prepared by neutralizing and dissolving in the aluminum chloride (Polymer) obtained in the above 1, aluminum sulfate, and so on.

It is a general technique to increase the basicity by high speed stirring by mixing about 10% of sodium chloride or aluminum sulfate + 1% of sodium silicate manufactured separately, and other examples.

Korean Patent Publication No. 10-0278777 uses aluminum dross, an oxide layer formed on the surface of a molten metal when dissolving aluminum metal or scrap, to produce aluminum hydroxide powder and amorphous form refractory materials. The recycling method of aluminum dross which makes phosphorus refractory material is described,

Publication No. 10-0206531 describes a method for preparing polyaluminum chlorosulfate (PACS) that avoids the formation of gypsum, has the ability to release soluble aluminum, and is stable at various temperatures.

Korean Patent Publication No. 91-3971 describes a method for preparing a basic aluminum chlorosulfate comprising the step of preparing a dough of calcium chloride and calcium carbonate and contacting the chlorocarbonated dough with aluminum sulfate.

Publication No. 91-4836 discloses aluminum ions by contacting aluminum oxide with hydrochloric acid and sulfuric acid in an aqueous medium. A method for preparing basic aluminum chlorosulfate is described by preparing an aqueous solution containing chlorine and sulfate ions, contacting the solution with alkaline earth metals and removing alkaline earth metal sulfates.

Publication No. 75-762 discloses a reaction product of an aqueous solution of a mixture of basic aluminum chloride and calcium chloride by reacting aluminum chloride, calcium carbonate, calcium bicarbonate, etc. in an aqueous medium, and converting the calcium chloride product of the reaction product into calcium sulfate. In order to make a basic aluminum chloride by addition reaction of aluminum sulfate, basic aluminum sulfate and the like is described,

In Publication No. 94-7094, an alkali metal silicate solution is mixed with an aluminum sulfate solution, an alkali metal aluminate solution or a solution of a precursor thereof is added to prepare a transparent solution, and the alkali metal aluminate mixture solution or precursor. A method for preparing a basic polyaluminum hydroxysulfate compound is described, wherein is partially substituted with a substance introducing at least one of a cation and an anion.

In Publication No. 89-272, hydrochloric acid was added to a reaction vessel with aluminum hydroxide, followed by reaction with sulfuric acid and water, followed by addition of calcium carbonate to obtain an aqueous polyaluminum chloride solution, followed by heating and drying with dilute hydrochloric acid. A method for producing polyaluminum chloride is disclosed,

Publication No. 95-3420 discloses a method of preparing aluminum sulfate by reacting aluminum hydroxide with sulfuric acid and water to produce an aqueous aluminum sulfate solution, and then adding sodium silicate and water to react.

All of the conventional techniques improve the properties of the product by increasing the basicity by using a water treatment agent dissolved in sulfuric acid or hydrochloric acid in aluminum hydroxide manufactured by Bauxite, all of them obtained by thermal decomposition of the raw minerals with caustic soda. Aluminum hydroxide is used as a raw material, and the method of increasing the basicity of aluminum salt (acid) with sodium almine or sodium silicate (alkaline) requires precipitation of high-speed stirring due to the precipitation of hydroxides as the input amount increases and gelation when mixed. As a result, problems with the device and long working hours (more than 2 hours) have been difficult.

In order to solve the above problems, the present invention is to dissolve the dross (ash) containing aluminum metal (caustic) with a caustic soda solution and filtered to form a precipitate with sodium silicate and to filter the precipitate A method of decomposing with sulfuric acid or hydrochloric acid, which is conventionally prepared by decomposing conventional aluminum hydroxide bauxite as a raw mineral with high concentration of caustic soda at high temperature and high pressure, followed by hydrolysis or seeding (hydroxyl). The raw material manufactured by adding about 20% of aluminum powder) should be thermally decomposed about 120 ℃ with caustic soda, and the high-speed stirring is necessary for a long time to solve this problem because it does not gelate well when preparing the precipitate with sodium silicate. It takes a lot of expenses such as expenses, working time, etc., but in the present invention, when the aluminum ash is dissolved in caustic soda, Because it was decomposed to provide a method for producing a basic aluminum silicate from standing because dissolution eliminates the need for separate heating, efficient and economical aluminum material (Aluminium Dross) for that purpose.

In order to achieve the object as described above, the present invention is aluminum is a positive substance so that it is dissolved in both acid and alkali to form a compound to form an aluminum salt. At this time, the raw material used determines the manufacturing method and characteristics of the product.In the case of aluminum metal (metal), it dissolves without heating in acid or alkali, but forms a compound, but in the case of aluminum hydroxide manufactured from bauxite Except when dissolved, the heat supply by heating should be followed.

The reaction equation for decomposing aluminum metal and aluminum hydroxide into acids or alkalis is shown below.

   In the case of aluminum metal,

① 2Al + 6HCl → 2AlCl ₃ + 3H ₂ ↑

② 2Al + 3H ₂ SO ₄ → Al ₂ (SO ₄ ) ₃ + 3H ₂ ↑

③ 2Al + 2NaOH + 2H ₂ O → 2NaAlO ₂ + 3H ₂ ↑

In the above reaction scheme, all the reactions occur even though no heat is applied, and all of them generate hydrogen gas.

   In the case of aluminum hydroxide manufactured by Bauxite,

④ Al (OH) ₃ + 3HCl → AlCl ₃ + 3H ₂ O

⑤ 2Al (OH) ₃ + 3H ₂ SO ₄ → Al ₂ (SO ₄ ) ₃ + 6H ₂ O

⑥ Al (OH) ₃ + NaOH → NaAlO ₂ + 2H ₂ O

At this time, all of the water is generated, and the reaction proceeds without the heat supply by the heat of dilution and the heat of reaction in the reaction equation ⑤, but in equations ④ and ⑥, heat is insufficient to decompose the aluminum salt by the dilution heat alone, so it is necessary to separately supply heat.

In case of reacting aluminum hydroxide with hydrochloric acid (④), either open type or closed type should be chosen.In the open type, sulfuric acid should be mixed and dissolved to make sulfate ion into calcium salt to separate and increase basicity, and in closed type, it must be dissolved at high temperature and high pressure. Equipment costs are high.

All of the above methods have a number of patents to increase the basicity by using a water treatment agent, but all of them dissolve aluminum salts with acids or alkalis to increase basicity using alkaline substances.

The purity of the aluminum salt is represented by converting the aluminum content into aluminum oxide (Al ₂ O ₃ ) .The solubility of aluminum varies depending on the acid or alkali content (PH) and the temperature. The solubility also varies depending on the case.

In this case, aluminum is reacted in a metal state, and thus a reaction method is distinguished from that of a compound.

Table 1 shows the results of solubility test by dissolving aluminum hydroxide (Al ₂ O ₃ = 60 wt%) manufactured by Bauxite with 50% liquid caustic soda.

Table 1

SampleNo Al (OH) ₃ : NaOH (50%) Al ₂ O ₃ content (%) importance Storage (hydrolysis) Remarks One 1: 1.5 17 1.390 Hydrolysis after about 20 days 2 〃 18 1.423 〃 3 〃 19 1.460 About 25 days 4 1: 1.7 16 1.390 30 days 5 〃 17 1.426 〃 6 1: 1.7 18 1.467 About 35 days 7 1: 1.9 15 1.388 About 40 days 8 〃 16 1.426 〃 9 〃 17 1.465 About 45 days 10 1: 2.1 14 1.384 About 50 days 11 〃 15 1.421 About 55 days 12 〃 16 1.462 〃 13 1: 2.3 13 1.372 2 months later 14 〃 14 1.411 〃 15 〃 15 1.455 2.5 months later 16 1: 2.5 12 1.357 Hydrolysis after 3 months 17 〃 13 1.400 3.5 months later 18 〃 14 1.443 〃 19 1: 2.7 11 1.342 4 months 〃 20 〃 12 1.381 4.5 months later 21 〃 13 1.427 5 months later 22 1: 2.9 10 1.317 〃 23 〃 11 1.360 About 6 months 24 〃 12 1.406 〃 25 1: 3.1 9 1.293 About 10 months 26 〃 10 1.337 About 11 months 27 〃 11 1.384 About 12 months 28 1: 3.3 8 1.266 Over 1 year 29 〃 9 1.310 〃 30 〃 10 1.356 〃

As can be seen from the above experiment, when the aluminum salt is decomposed into caustic soda, hydroxide is precipitated by hydrolysis when the sodium hydroxide or aluminum content is low, and the shelf life is shortened. When dissolving the aluminum compound with caustic soda, increasing the caustic soda content or alumina content can make the aluminum compound (when reacting with caustic soda) by using the property of hydrolysis well if it is lowered without delay or hydrolysis. .

      Experimental results to confirm this again are shown in Table 2.

Table 2

SampleNo Al (OH) ₃ : NaOH (50%) Al ₂ O ₃ content (%) importance Storage (hydrolysis) Remarks One 1: 2.5 11 1.298 Hydrolysis after 3 months 2 〃 12 1.333 〃 3 〃 13 1.371 〃 4 1: 2.6 11 1.310 〃 5 〃 12 1.342 〃 6 〃 13 1.381 〃 7 1: 2.7 11 1.315 4 months later 8 〃 12 1.353 〃 9 1: 2.7 13 1.394 4 months later 10 1: 2.8 10 1.286 〃 11 〃 11 1.324 〃 12 〃 12 1.364 〃 13 1: 2.9 10 1.294 5 months 〃 14 〃 11 1.334 〃 15 〃 12 1.376 〃 16 1: 3.0 10 1.300 6 months 〃 17 〃 11 1.341 〃 18 〃 12 1.383 〃 19 1: 3.1 9 1.272 10 months 〃 20 〃 10 1.311 〃 21 〃 11 1.354 〃 22 1: 3.2 9 1.278 11 months 〃 23 〃 10 1.319 〃 24 〃 11 1.363 〃

The difference in specific gravity in Table 1 and Table 2 is judged according to the indoor temperature difference at the time of measurement, Table 1 is the experimental value in May 2000 and Table 2 was measured in August 2000, so the room temperature is between 15 ℃ ~ 25 ℃. It is judged to be.

In the case of dissolving aluminum hydroxide with caustic soda for long-term preservation, it was judged that 50% solution of caustic soda should be used 2.5 times or more than aluminum hydroxide (Al ₂ O ₃ = 60 wt%).

Above, the aluminum was dissolved in caustic soda and applied to PACS and PASS manufacturing experiments. Also, the characteristics of dross generated in aluminum ingot manufacturing plant were investigated.

Aluminum material (Aluminum dross) is described in the method of recycling the patent 10-0278777 (Register No.) Aluminum material (aluminum dross), the content of the aluminum metal contained in the aluminum oxide layer depends on the sieve.

Table 3-1 Al, metal content of aluminum dross

No Al, metal content (A)% Al, metal content (B)% One 44.1 33.5 2 42.0 28.0 3 42.0 35.0 4 36.0 31.0 5 33.5 38.0

In the table above, A and B filter out aluminum dross through a sieve (approx. 200 mesh) according to the purpose, divided into a pass-through (A) and a non-pass-through (B), and convert Al and metal into aluminum hydroxide. By applying the results obtained in Table 1 and Table 2, the reaction equation is as follows.

2Al + 2NaOH + 2H ₂ O 2NaAlO ₂ + 3H ₂ ↑

            2 x 27: 2 (23 + 16 + 1) = 54: 80 = 1: 1.482

Caustic soda reacts at 2.964 times because it uses 50% solution (2 times 1.482)

When Al, metal is converted into Al (OH) ₃ ,

Al: Al (OH) ₃ → 27: 78 = 1: 2.889

Therefore, when converting Al and metal in aluminum dross into Al (OH) ₃ , the amount of aluminum hydroxide becomes 2.889 times the content of metal in the aluminum dross.

In addition, when dissolving aluminum dross with caustic soda, the color of the filtered solution becomes colorless or pale yellow depending on the amount of caustic soda, so that the amount of caustic soda is kept to a minimum to form a precipitate with sodium silicate. Giving helps improve whiteness.

In addition, since the amount of precipitate is changed to white due to the addition of caustic soda after dissolution, the amount of caustic soda and sodium silicate should be changed according to the use.

Precipitates used in the present invention are as follows.

Sodium Alkoxide: 2NaAlO ₂ → Na ₂ O.Al ₂ O ₃

Sodium Silicate: Na ₂ SiO ₃ → Na ₂ O.xSiO ₂ ㆍ yH ₂ O

Na ₂ O and Al ₂ O ₃ + Na ₂ O and _{xSiO 2 + yH 2 O → Me} 2 / n O and Al ₂ O ₃ and xSiO ₂ and yH ₂ O

Na ₂ OAl ₂ O ₃ → 23 × 2 + 16 + 27 × 2 + 16 × 3 = 46 + 16 + 54 + 48 = 164

Na ₂ OSiO ₂ → 23 × 2 + 16 + 28 + 16 × 2 = 46 + 16 + 28 + 32 = 122

In the case of sodium silicate, commercial products are classified into Nos. 1 to 3 according to the ratio of caustic soda and silica.Sodium silicate used here is SiO ₂ = 28-30%, Na ₂ O = 9-10% (commercially available) 3) was used.

Sodium silicate (Na ₂ SiO ₃ ); (Na ₂ O.xSiO ₂ + yH ₂ O), but x is three times the amount of Na ₂ O and y is 20-30. It depends on the amount of water evaporated during the reaction or the standard of sodium silicate (No. 1 to 3).

The ratio of SiO ₂ : Na ₂ O is 28 + 32: 23 × 2 + 16 = 60: 62, which is almost 1: 1, but is about 3: 1 due to manufacturing problems.

Therefore, (Me ₂ ) _n O.Al ₂ O ₃ ㆍ nSiO ₂ ㆍ yH ₂ O must be reacted with (Na ₂ O) ₂ ㆍ Al ₂ O ₃ ㆍ SiO ₂ ㆍ yH ₂ O, but sodium silicate is reacted with Na ₂ O: SiO ₂ = 1: 3 (commercially available product No. 3) the use hayeoteumeuro product is in Na ₂ O and Al ₂ O ₃ and Na ₂ O ₃ and SiO ₂ and O ₂ yH (y is 20 to 30).

In addition, when decomposing aluminum material into caustic soda, the ratio of Al and NaOH is Al (OH) ₃ (60% by weight of Al ₂ O ₃ ): NaOH (50%) = 1: 1.2. The amount of caustic soda is not constant because it is added to prevent the formation of hydroxide precipitates.

In the formula _{Al A (OH) B (SO} 4) C (SiO x) D (H 2 O) E of polyester aluminate arithmetic monophonic silicate (PASS) of the basic aluminum silicate produced in the present invention,

A = 1.0, B = 0.75 to 2.0, C = 0.3 to 1.12, D = 0.005 to 0.1, E ≧ 4, 2 ≦ x ≦ 4,

 Briefly summarized the manufacturing scheme,

(Na ₂ O) _x Al ₂ O ₃ ㆍ SiO ₂ + yH ₂ SO ₄ → Al _A (OH) _B (SO ₄ ) _C (SiO _x ) _D (H ₂ O) _E

 to be.

Here, the content of alumina and silica is kept constant, but the amount of Na ₂ O and H ₂ SO ₄ may vary depending on the filtration conditions and pH control conditions.

In the basic aluminum silicate prepared in the present invention, the polyamic acid chlorosilicate (PACS) is represented by the formula [Al (OH) _a (Cl) _b (SiO _x ) _c (H ₂ O) _d ] _n ,

Al _m (OH) _n Cl _x and Al _m (OH) _n (SO ₄ ) _y

        m = 2 or more, n = 3 or more, x = 4, y is 3 or more.

    To summarize the equation briefly,

(Na ₂ O) _x Al ₂ O ₃ ㆍ SiO ₂ + yHCl → [Al (OH) _a (Cl) _b (SiO _x ) _c (H ₂ O) _d ] _n

It can be seen that.

Even when dissolved in hydrochloric acid, the amount of NaOH and sodium silicate can be arbitrarily changed in consideration of the amount of filtration or whiteness precipitate produced during the manufacturing process of the precipitate. In order to change the dosage, the content of each component of the reaction scheme is determined by changing the dosage.

Through the following examples will be described the present invention in detail.

Examples 1-7 (Preparation of Intermediate; Precipitation)

First, 2,100 ml of water was added to a 20-l container (stainless steel), and 1,050 g of 33% NaOH (1.75 times the amount of aluminum dross) was added, followed by dissolving and filtering 600 g of aluminum material (600 g of aluminum dross). 750 g of 33% caustic soda was added and sodium silicate having a SiO ₂ : Na ₂ O weight ratio of 3.22: 1.0 was added to the solution in an amount of 6% to 18% by weight (Me ₂ ) _n O.Al ₂ O ₃ .xSiO ₂ • yH ₂ O (Me: Na, Ca, K, n: 1 to 5, x: 2, y: 20 to 30) An intermediate having a structural formula (precipitate) was prepared.

Scheme Summary

Na ₂ O and Al ₂ O ₃ + Na ₂ O and _{xSiO 2 + yH 2 O → (} Me 2) n O and Al ₂ O ₃ and xSiO ₂ and yH ₂ O

Examples 8-13 (Preparation of Intermediate; Preparation of Precipitate)

First, 2,100 ml of water was added to a 20-l container (stainless steel), and 1,050 g of 33% NaOH (1.75 times the amount of aluminum dross) was added, followed by dissolving and filtering 600 g of aluminum material (aluminum dross) of 35% by weight of aluminum. after adding 33% sodium hydroxide 750g and SiO ₂ with respect to the solution: Na ₂ O weight ratio of 3.22: 1.0 by mixing a sodium silicate with 12% by weight (Me _{2) n} O and Al ₂ O ₃ and xSiO ₂ and yH ₂ An intermediate (precipitate) having an O (Me: Na, Ca, K, n: 1 to 5, x: 2, y: 20 to 30) structure was prepared.

Examples 13-16 (Preparation of Intermediate; Precipitation)

First, 2,100 ml of water is added to a 20-l container (stainless steel), and the amount of 33% NaOH is changed [1,050 g (1.75 times based on the amount of aluminum dross)], 1400 g, 1750 g, and 2100 g, followed by aluminum content of 35 wt% aluminum. After dissolving and filtering 600 g of aluminum dross, 750 g of 33% caustic soda was added and 10 wt% of sodium silicate having a SiO ₂ : Na ₂ O weight ratio of 3.22: 1.0 was added to the solution (Me ₂ ) _n O Al ₂ O ₃ xSiO ₂ yH ₂ O (Me: Na, Ca, K, n: 1 to 5, x: 2, y: 20 to 30) An intermediate having a structural formula (precipitate) was prepared.

Table 3-2 Sediment Preparation Method

Example Aluminum material: NaOH: water Sodium silicate usage (% of solution) Sediment Generation Remarks One 600g: 1,800g: 2,100g 6 19.9% (humidity product) 2 〃 8 23.8% 〃 3 〃 10 41.3% 〃 4 〃 12 45.2% 〃 5 〃 14 48.2% 〃 6 〃 16 50.1% 〃 7 〃 18 50.5% 〃 8 600g: 1,050g: 2,100g 6 22.3% 〃 9 〃 8 26.2% 〃 10 〃 10 31.9% 〃 11 〃 12 39.7% 〃 12 〃 14 46.6% 〃 13 〃 16 47.5% 〃 14 〃: 1,400g: 〃 〃 35.6% 〃 15 〃: 1,750g: 〃 〃 37.2% 〃 16 〃: 2,100g: 〃 〃 39.4% 〃

Examples 17-20 (final material preparation; production of basic aluminum silicate)

After dissolving aluminum dross with caustic soda (33% solution) and filtering, 10% by weight of sodium silicate was added to the filtrate to make precipitate for 24 hours, and 35% hydrochloric acid was added to the prepared precipitate by weight 1: NaAlO ₂ prepared by adding 1 and decomposing the Al contained in the aluminum dross into Al (OH) ₃ in 3.5 times water and 33% caustic soda 1.75 times (1/2 of the amount). Polyaluminum chloride silicate having the following structural formula was prepared by varying the amount of aluminum (soda aldehyde) and aluminum.

(Na ₂ O) _x Al ₂ O ₃ ㆍ SiO ₂ + yHCl → [Al (OH) _a (Cl) _b (SiO _x ) _c (H ₂ O) _d ] _n

m = 2 or more, n = 3 or more, x = 4, y is 3 or more

Examples 21-24 (final material preparation; preparation of basic aluminum silicate)

After dissolving aluminum dross with caustic soda (33% solution) and filtering, 10% by weight of sodium silicate was added to the filtrate to make a precipitate for 24 hours, and 98% sulfuric acid was added to the prepared precipitate by weight 1: NaAlO ₂ prepared by adding 1 and decomposing the Al contained in the aluminum dross into Al (OH) ₃ in 3.5 times water and 33% caustic soda 1.75 times (1/2 of the amount). Polyaluminum sulfate silicate having the following structural formula was prepared by varying the amount of aluminum (soda aldehyde) and aluminum.

(Na ₂ O) _x Al ₂ O ₃ ㆍ SiO ₂ + yH ₂ SO ₄ → Al _A (OH) _B (SO ₄ ) _C (SiO _x ) _D (H ₂ O) _E

A = 1.0, B = 0.75 ~ 2.0, C = 0.3 ~ 1.12, D = 0.005 ~ 0.1, E ≥4, 2 ≤x ≤4

Table 3-3 Preparation of Basic Aluminum Silicate According to the Example

Example Sediment amount Type and amount of acid Alum Usage NaAlO ₂ PH importance 17 400 g (humidity product) 1: 1 HCl 1,000g - 225 g 0.60 1.182 18 200g 〃   〃 500g 500 g 50 g 0.57 1.128 19 100 g (dry) 1: 1 HCl 1,000g       - 20 50g 〃 1: 1 HCl 500g      500 g 21 200 g (humidity product) 1: 1 H ₂ SO ₄ 1,000g - 575 g 0.37 1.265 22 100g 〃    500 g 500 g 225 g 0.38 1.260 23 50 g (dry) 1: 1 H ₂ SO ₄ 1,000g       - 24 25g 〃 1: 1 H ₂ SO ₄ 500g      500 g

Experimental Example 1

In Table 4, aluminum dross used Al, a metal content of 35%, caustic soda concentration of 33%, and sodium silicate SiO ₂ : Na ₂ O ratio of 3.22: 1.0.

Table 4 Sediment Production

Example Aluminum material: NaOH: water Sodium silicate usage (% of solution) Sediment Generation Remarks One 600g: 1,800g: 2,100g 6 19.9% (humidity product) 2 〃 8 23.8% 〃 3 〃 10 41.3% 〃 4 〃 12 45.2% 〃 5 〃 14 48.2% 〃 6 〃 16 50.1% 〃 7 〃 18 50.5% 〃

In the test method, 2,100 ml of water was first added to a 20-l container (stainless steel), and then 1,050 g of 33% NaOH (1.75 times the amount of aluminum dross) was added, followed by dissolving 600 g (Al, 35 weight% of metal) of dross. After filtration, 750 g of 33% caustic soda was added, and the amount of precipitate formed by varying the amount of sodium silicate to 6-18% by weight was measured.

 The precipitate was filtered and washed five times with water and then the amount was measured in a humid state.

From the beginning, the amount of caustic soda was used in the minimum amount without decomposing it into the required amount, so that it was difficult to filter when the color of the filtrate and the concentration were high during filtration.

As shown in Table 4, it can be seen that the amount of precipitate increases according to the amount of sodium silicate used when dissolving aluminum material (aluminum dross) with caustic soda.

Experimental Example 2

The precipitates generated by using caustic soda and sodium silicate are shown in the following table.

Table 5 Sediment Production

Example dross: NaOH: water Sodium silicate usage (% of solution) Sediment Generation Remarks 8 600g: 1,050g: 2,100g 6 22.3% 9 〃 8 26.2% 10 〃 10 31.9% 11 〃 12 39.7% 12 〃 14 46.6% 13 〃 16 47.5%

As shown in Table 5, when sodium silicate is maintained to keep the dissolution condition of aluminum dross constant and the precipitate is formed, the amount of precipitate formation increases depending on the amount of sodium silicate, but the filtration operation is performed when more than 12% It is difficult to maintain the dosage of sodium silicate at about 12% by weight.

The experimental method was the same as the method shown in Table 4, but the experiment was conducted with a solution after dissolving aluminum dross without adding caustic soda. This is because the aluminum compound is hydrolyzed and precipitated into the hydroxide, so the experiment should be performed within 24 hours after filtering the dross solution.

Experimental Example 3

Table 6 Sediment Formation (According to Caustic Sodium Consumption)

Example dross: NaOH: water Sodium silicate usage (% of solution) Sediment Generation Remarks 10 600g: 1,050g: 2,100g 10 27.7% (humidity product) 14 〃: 1,400g: 〃 〃 35.6% 〃 15 〃: 1,750g: 〃 〃 37.2% 〃 16 〃: 2,100g: 〃 〃 39.4% 〃

The experimental method is shown in Table 4, but dissolved by 1.75 times of caustic soda (33%) based on the amount of aluminum dross, filtered, and then added 10% by weight, 20% by weight, and 30% by weight of caustic soda to the filtrate. Afterwards, the amount of precipitate generated by increasing caustic soda was measured.

As shown in Table 5, the amount of precipitate produced increases with increasing caustic soda.

Experimental Example 4

The precipitates obtained in Tables 4 and 5 were dissolved in 1: 1 hydrochloric acid solution and 1: 1 sulfuric acid solution, and various properties were investigated as follows.

Table 7 PACS and PASS Manufacturing Experiment

Example Sediment amount Type and amount of acid Alum Usage NaAlO ₂ 17 400 g (humidity product) 1: 1 HCl 1,000g - 225 g 18 200g 〃 500 g 500 g 50 g 21 200g 〃 1: 1 H ₂ SO ₄ 1,000g - 575 g 22 100g 〃 500 g 500 g 225 g

     1) In Table 6, 10% by weight of sodium silicate (relative to the solution) was added to the filtered solution by dissolving aluminum dross in 33% NaOH to produce a precipitate for 24 hours, and a filtered product (water content: 75%) was used.

2) A commercial product having 8% by weight of Al ₂ O ₃ was used as aluminum.

3) NaAlO ₂ (sodium aldehyde) is converted into Al (OH) ₃ in aluminum dross and converted into Al (OH) ₃ with 3.5 times water and 33% caustic soda 1.75 times (1/2 of the volume). Then used.

(Al ₂ O ₃ = 10.4%, NaOH = 9.2%)

     4) 35% hydrochloric acid and 98% sulfuric acid were tested.

     5) In the above experiment, since the dissolved amount of the precipitate in hydrochloric acid or sulfuric acid is more than 10% by weight, gelation (within 12 hours) was added soda amine to prevent the gelation of the melt.

Comparison of Coagulation Effect between PACS and PASS Prepared with Alum

Table 8 Agglomeration Effect as Water Treatment Agent

Example Sediment amount Type and amount of acid Size of Floc Sedimentation rate 19 100 g (dry) 1: 1 HCl 1,000g versus speed 20 50g 〃 1: 1 HCl 500g + Alum 500g medium usually 23 50g 〃 1: 1 H ₂ SO ₄ 1,000g medium usually 24 25g 〃 1: 1 H ₂ SO ₄ 500g + Alum 500g small Slow

Experimental Example 5

Aluminum dross was dissolved in caustic soda (33% solution), filtered, and sodium silicate was added to the filtrate by 12% by weight to form a precipitate. The results of testing the effect as a water treatment agent by the production of sulfasilicate aluminate and polychlorinate silicate (PACS) are as follows.

SampleNo Sediment amount Kind of the mountain PH importance Water treatment effect One 600 g 1: 1 H ₂ SO ₄ 500g 1.46 1.244 Floc is big and sinks quickly 2 310 g 1: 1 HCl 500g 1.50 1.127 Floc is largest and sinks quickly 3 Alum Al ₂ O ₃ = 8% 1.31 1.320 Floc is small and slowly sinks

      1) When the precipitate is dissolved in sulfuric acid, it is difficult to dissolve due to gelation. However, dissolution and dissolution can be performed within 10 minutes by dissociation and dissolution in an experimental ball mill.

       2) The small amount of dissolved solution in hydrochloric acid seems to be due to the lower content of hydrochloric acid than sulfuric acid.

       3) The amount of dissolution is different depending on the type of acid. If the amount of dissolution is small (excess acid), gelation occurs. If the amount of dissolution is high, hydroxide precipitation occurs. This doesn't happen.

       4) The performance of water treatment agent is much higher than that of sulphate, and the performance of the solution in which the precipitate is dissolved in hydrochloric acid or sulfuric acid is superior to that of aluminum sulfate, which is a simple compound.

       5) 1 ml each of the solution of the precipitate dissolved in acid and the aluminum sulfate solution were added, and 1,000 ml of water was added to a 1 l beaker and neutralized with 33% caustic soda.

Review of experimental results

1) When aluminum is a metal state or compound [Al (OH) ₃ ], Al (OH) ₃ (60 ~ 65% by weight of Al ₂ O ₃ ), which is the theoretical value when dissolved in alkali (33%, 50% NaOH): NaOH ( 50%) Reaction (dissolution) in the ratio of 1: 1.1 ~ 1.15 and in the case of metal, the reaction proceeds without applying heat, but in the case of a compound, it must be supplied with heat of 115 ℃ or higher to dissolve. It can be seen from Tables 1 and 2 that the alkali content should be high to prevent hydrolysis from occurring.

  2) In order to form precipitates with sodium silicate in the alkali decomposition solution of aluminum dross, the amount of sodium silicate must be increased or the alkali content must be increased. Tables 4-5

3) In order to prevent gelation when dissolving the precipitate with hydrochloric acid or sulfuric acid, free sulfuric acid or hydrochloric acid should be removed with the filtered solution (NaAlO ₂ ) by dissolving aluminum material to prevent gelation. Could.

    4) It is necessary to keep the pH of solution at 1.0 ~ 1.5 to prevent gelation when dissolving precipitate with hydrochloric acid or sulfuric acid. (You can dissolve only the precipitate, reduce the amount of precipitate, and adjust the pH with sodium phosphate.)

  5) As a result of testing the water treatment effect of the produced product, it was found that the hydrochloride has larger Floc size and faster sedimentation rate than the sulfate as shown in Table 7.

As described above, the present invention uses PACS (Poly Aluminum Chloric Silicate) and PASS (d) using dross, which is an essential ingredient in the production of aluminum ingots produced in large quantities (about 10,000-20,000 tons / month). It produces Poly Aluminum Sulfuric Silicate, which not only contributes to the cost and environmental pollution caused by the disposal of aluminum ash, but also significantly lowers the cost of manufacturing water treatment and significantly improves the treatment effect.

Claims (5)

In the method for producing a basic aluminum silicate, an aluminum material (Aluminium dross) is dissolved in caustic soda (33% solution), filtered, and sodium silicate is added to the filtrate 10% by weight to make a precipitate for 24 hours, to prepare a precipitate Acid was added 1: 1 to the weight, and Al contained in aluminum dross was converted into Al (OH) ₃ to decompose 3.5 times of water and 1.75 times of 33% caustic soda. A method for producing basic aluminum silicate by varying the amount of NaAlO ₂ (sodium aldehyde) prepared by filtration and aluminum. The method of claim 1, wherein the acid is any one compound selected from 35% hydrochloric acid and 98% sulfuric acid. In the method of producing basic aluminum silicate, aluminum material (Aluminum dross) is dissolved in caustic soda (33% solution), filtered, and sodium silicate is added to the filtrate by 10% by weight to form a precipitate for 24 hours, and to the prepared precipitate. 35% hydrochloric acid is added 1: 1 by weight, and Al in aluminum dross is converted into Al (OH) ₃ to 3.5 times water and 33% caustic soda 1.75 times (1/2 of the volume). A method for producing a basic aluminum silicate, characterized in that polyaluminum silicate having the following structural formula is prepared by varying the amount of NaAlO ₂ (sodium aldehyde) prepared by decomposition by filtration and aluminum. (Na ₂ O) _x Al ₂ O ₃ ㆍ SiO ₂ + yHCl → [Al (OH) _a (Cl) _b (SiO _x ) _c (H ₂ O) _d ] _n m = 2 or more, n = 3 or more, x = 4, y is 3 or more, A = 1.0, B = 0.75 ~ 2.0, C = 0.3 ~ 1.12, D = 0.005 ~ 0.1 In the method for producing a basic aluminum silicate, an aluminum material (Aluminum dross) is dissolved in caustic soda (33% solution), filtered, and sodium silicate is added 10% to the filtrate to form a precipitate for 24 hours, 98 to the precipitate prepared % Sulfuric acid is added 1: 1 by weight, and Al in aluminum dross is converted into Al (OH) ₃ to 3.5 times water and 33% caustic soda 1.75 times (1/2 of the volume). A method for producing a basic aluminum silicate, characterized by producing polyaluminum sulfate having the following structural formula by changing the addition amount of NaAlO ₂ (sodium aldehyde) prepared by decomposition and filtration. (Na ₂ O) _x Al ₂ O ₃ ㆍ SiO ₂ + yH ₂ SO ₄ → Al _A (OH) _B (SO ₄ ) _C (SiO _x ) _D (H ₂ O) _E A = 1.0, B = 0.75 to 2.0, C = 0.3 to 1.12, D = 0.005 to 0.1, E ≧ 4, 2 ≦ x ≦ 4, y is 3 or more The method according to any one of claims 1, 3 and 4, wherein the precipitate (intermediate) is placed in a 20 liter container (stainless steel) with 2,100 ml of water and 1,050 g of 33% NaOH (1.75 times the amount of aluminum dross). After addition, 600 g of aluminum material (aluminum dross) containing 35% by weight of aluminum was dissolved, filtered, and then 750 g of 33% caustic soda was added, and 6 parts of sodium silicate having a SiO ₂ : Na ₂ O weight ratio of 3.22: 1.0 was added to the solution. (Me ₂ ) _n O.Al ₂ O ₃ ㆍ xSiO ₂ ㆍ yH ₂ O (Me: Na, Ca, K, n: 1-5, x: 2, y: 20-30 ) A method for producing a basic aluminum silicate, characterized in that to prepare a precipitate (intermediate) having a structural formula.