JP2001137858A - Water treatment method and titanium oxide electrode to be used therein - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily and inexpensively remove scale in water. SOLUTION: Water is electrolyzed using TiOx(0<;x<;2) as an anode. Then Ca2+, Mg2+, or the like, in water are precipitated and removed. Since the titanium oxide electrode to be used is obtained at a low cost, water treatment cost is reduced. Also, by using it for a long period, scale is removed and also based on an electrochemical reaction, sometimes NaCl is produced in water, so that propagation of microorganisms can be prevented by the sterilization effect on water.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a water treatment method and a titanium oxide electrode used for the method.

[0002]

2. Description of the Related Art There are various water treatment methods for removing scale in water. For example, there are a method of collecting Ca ²⁺ and Mg ²⁺ in water using an ion exchange resin, a method of masking using EDTA, a distillation method, and the like.

[0003]

However, the former two of the above-mentioned conventional methods have a problem that it is difficult to prevent the propagation of microorganisms in long-term use. In addition, in the case of the distillation method, pure water can be obtained, but a huge amount of energy is required, and there is a problem that the cost is too high.

Accordingly, the present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a water treatment method capable of reducing costs and a titanium oxide electrode used for the same.

[0005]

The present invention has the following arrangement to achieve the above object. That is, TiOx (0 <x <2)
Is used as an anode to electrolyze water, and Ca ²⁺ , Mg ²⁺
Alternatively, the method is characterized in that colloidal particles of silicon are precipitated and removed. The titanium oxide electrode can be obtained at low cost, and the cost of water treatment can be reduced. In addition, the scale may be removed over a long period of use, and NaClO may be generated in water by an electrochemical reaction, which may prevent the growth of microorganisms.

The cathode is made of Ti, Fe, graphite, Cu, or T
iOx (0 <x <2) or the like can be used.

The method of the present invention is characterized in that water is electrolyzed using TiOx (0 <x <2) as an anode to precipitate and remove iron ions in the water. In this case, the same cathode as described above can be used.

[0008] By electrolysis of water using TiOx (0 <x <2) as an anode, scale is removed and Na is added to the water.
It can produce ClO, sterilize, decolorize and deodorize water, and prevent the growth of microorganisms.

Further, the titanium oxide electrode according to the present invention has a
O ₂ powder and SiO ₂ powder are mixed using a binder,
It is molded into the required shape, and this molded product is fired at 1200 ° C to 1450 ° C in an oxidizing atmosphere, and then fired in a reducing atmosphere. Things. It can be obtained at low cost and is suitable for use in the water treatment method.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail. First, a method for manufacturing a titanium oxide electrode will be described. The powder of TiO _{2 and} the powder of SiO ₂ are mixed at a weight ratio of approximately 8: 2 (the mixing ratio is arbitrary). At this time, the TiO ₂ powder and the SiO ₂ powder are mixed using a binder such as methyl cellulose and water. It is preferable to use a fine powder of about 1 μm for the TiO ₂ powder and a fine powder of about 3 μm for the SiO ₂ powder.

Then, it is formed into a required shape as an electrode to be used by a forming die. The molded product is placed in a firing furnace, and fired at a high temperature of 1200 ° C. to 1450 ° C. for about 30 hours while blowing air to blow off the binder component. Next, calcination is performed for about 10 hours in a reducing atmosphere such as hydrogen to reduce TiO ₂ to TiO x (0 <x <2) to form an N-type semiconductor electrode. Titanium dioxide (TiO ₂ ) has no conductivity but has oxygen deficiency
TiOx (0 <x <2) has conductivity.

Using the titanium oxide electrode obtained as described above as an anode, river water was electrolyzed for water treatment.

Example 1 Anode: TiOx (0 <x <2) Cathode: Fe 0.1 A × 65 VDC

[0014]

[Table 1] As shown in Table 1, the scale was effectively removed.

Example 2 Anode: TiOx (0 <x <2) Cathode: Fe 17 mA × 12 VDC

[0016]

[Table 2] As shown in Table 2, the scale was effectively removed.

Example 3 Anode: TiOx (0 <x <2) Cathode: Ti 0.3A × 54VDC

[0018]

[Table 3] As shown in Table 3, the scale was effectively removed.

Example 4 Anode: TiOx (0 <x <2) Cathode: Ti 0.2 A × 70 VDC

[0020]

[Table 4] As shown in Table 4, the scale was effectively removed.

Example 5 Anode: TiOx (0 <x <2) Cathode: graphite 0.1A × 75VDC

[0022]

[Table 5] As shown in Table 5, the scale was effectively removed.

Example 6 Anode: TiOx (0 <x <2) Cathode: Ti 0.2A × 27VDC

[0024]

[Table 6] As shown in Table 6, the scale was effectively removed.

Example 7 Anode: TiOx (0 <x <2) Cathode: Cooling tower water of TiA company

[0026]

[Table 7] As is clear from Table 7, Ca ²⁺ , Mg ²⁺ and Fe ²⁺ were removed. In addition, silicon components (suspended in water in a colloidal state) also precipitated in the form of SiO ₂ and could be removed.

Example 8 Anode: TiOx (0 <x <2) Cathode: Cooling tower water of TiB company

[0028]

[Table 8] As is clear from Table 8, Ca ²⁺ , Mg ²⁺ and Fe ²⁺ were removed. In addition, silicon components (suspended in water in a colloidal state) also precipitated in the form of SiO ₂ and could be removed.

Example 9 Anode: TiOx (0 <x <2) Cathode: TiOx (0 <x <2) Salt is added to river water

[Table 9]

[0030]

[Table 10]

[0031]

[Table 11]

[0032]

[Table 12]

[0033]

[Table 13]

[0034]

[Table 14]

[0035]

[Table 15]

[0036]

[Table 16]

As is clear from Tables 9 to 16, when a small amount of salt was added to river water and electrolysis was performed using the above electrode, NaClO was produced. As the amount of added salt increases, the amount of generated NaClO tends to increase. NaClO has a bactericidal, decolorizing and deodorizing effect. Therefore, it is suitable for water treatment. By the way, when the pigment was added to the river water and electrolyzed using the above electrode, the color of the pigment disappeared.

Example 10 Anode: TiOx (0 <x <2) Cathode: Ti River water itself is electrolyzed. 0.05A, 4V Initial value COND = 251μ / cm ORP = + 100mV PH = 8.89 Cl = 13.2mg / l

[0039]

[Table 17] As is clear from Table 17, NaClO is produced.

Example 11 Anode: TiOx (0 <x <2) Cathode: Ti River water itself was subjected to electrolytic treatment. 0.3A, 10V Initial value COND = 296μ / cm ORP = + 160mV PH = 9.01 Cl = 20.94mg / l

[0041]

[Table 18] As is clear from Table 18, NaClO is generated.

Example 12 Anode: TiOx (0 <x <2) Cathode: Fe salt was added to distilled water (Cl = 200 mg / l) 0.1 A, 15 V

[0043]

[Table 19]

Example 13 Anode: TiOx (0 <x <2) Cathode: Graphite Salt added to distilled water (Cl = 200 mg / l) 0.1 A, 16.12 V

[0045]

[Table 20]

Example 14 Anode: TiOx (0 <x <2) Cathode: Add salt to Cu distilled water (Cl = 200 mg / l) 0.1 A, 20 V

[0047]

[Table 21]

Example 15 Anode: TiOx (0 <x <2) Cathode: Ti Salt added to distilled water (Cl = 1000 mg / l) 0.4 A, 16.2 V

[0049]

[Table 22] As is clear from Tables 19 to 22, NaClO was generated even when the cathode electrode was changed.

[0050]

As described above, according to the present invention, underwater
Ca ²⁺ , Mg ²⁺ , iron ions, and silicon colloid can be effectively precipitated and removed, and the titanium oxide electrode used can be obtained at low cost, so that the cost of water treatment can be reduced.
In addition, the scale may be removed by long-term use, and NaClO may be generated in water by an electrochemical reaction, and the germicidal effect of water may prevent the growth of microorganisms.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat ゛ (Reference) C02F 1/50 520 C02F 1/50 540B 531 560F 540 5/00 610B 560 620B 5/00 610 C25B 1/26 C 620 11/04 Z C25B 1/26 11/06 B 11/04 C02F 1/46 102 11/06

Claims (5)

[Claims] An electric component of water using TiOx (0 <x <2) as an anode.
Perform the solution and add Ca ²⁺, Mg²⁺Or silicon colloid particles
A water treatment method comprising precipitating and removing particles. 2. The cathode is made of Ti, Fe, graphite, Cu or T
The water treatment method according to claim 1, wherein iOx (0 <x <2) is used. 3. A water treatment method comprising performing electrolysis of water using TiOx (0 <x <2) as an anode to precipitate and remove iron ions in the water. 4. A water treatment method comprising performing electrolysis of water using TiOx (0 <x <2) as an anode to generate NaClO in water. 5. A powder of TiO _{2 and} a powder of SiO ₂ are mixed by using a binder and molded into a required shape.
5. A calcination in an oxidizing atmosphere at a temperature of from 1 to 1450 ° C. and then in a reducing atmosphere. Titanium oxide electrode used for water treatment method.