JP2017127822A - Knitted fabric for removing volatile organic compound - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a catalyst for removing a VOC by catalytic burning that has a low pressure drop and is able to deal with a channel of a complicated shape.SOLUTION: A metal species of high VOC burning ability is carried by a knitted fabric formed by knitting or weaving inorganic fiber yarn to produce a knitted fabric for removing a VOC (hereinafter, VOC removal knitted fabric) that is excellent in heat resistance and flexibility and has low fuzz scattering. Gas permeability of the VOC removal knitted fabric is controlled by adjusting yarn density in knitting and weaving and thus pressure drop in a VOC channel and drift of an exhaust gas containing a VOC are suppressed. Strength and flexibility of the VOC removal knitted fabric are controlled by adjusting fineness and number of twists of the inorganic fiber yarn. Therefore, a catalyst for removing a VOC can be installed in the VOC channel of a complicated shape.SELECTED DRAWING: Figure 5

Description

The present invention relates to a VOC-removed knitted fabric in which a metal species having the ability to decompose and remove volatile organic compounds (hereinafter referred to as VOC) is supported on a knitted fabric having high heat resistance and excellent flexibility, and a manufacturing technique thereof.

(About VOC)
VOC is a general term for organic compounds that are volatile and become gaseous in the atmosphere, and include a wide variety of substances such as ethylene, butane, toluene, xylene, ethyl acetate, and formalin. These VOCs are considered as causative substances for organic solvent poisoning in the workplace such as sickness, sickness syndrome and sick building syndrome due to high airtightness of houses and offices, use of new building materials, printing, painting, adhesion and dry cleaning. Yes. In addition, with the revision of the Air Pollution Control Act in 2006, regulations on VOCs have been strengthened, and there is a demand for higher performance of VOC decomposition and removal equipment.

(Current VOC removal method)
Current methods of removing VOCs include “combustion methods” such as direct combustion method, heat storage combustion method and catalytic combustion method, and “adsorption method” in which VOC is adsorbed on adsorbents such as activated carbon and high silica zeolite.

The adsorption method has the merit that it can be recovered and reused when there is a single type of VOC, because VOC is physically adsorbed on the adsorbent and collected. However, when there are many types of VOCs generated, such as in printing and painting sites, the purification process after adsorption is complicated, so there are few merits of collection and reuse. In addition, there is a problem that the adsorption capacity is lowered when the VOC is sufficiently adsorbed on the adsorbent. On the other hand, the combustion method decomposes VOCs by combustion, so it is suitable for use in exhaust facilities in factories where VOCs are generated in large quantities and in large quantities.

Among these combustion methods, the catalytic combustion method is a method in which VOC is brought into contact with a catalyst having VOC combustion activity (hereinafter referred to as VOC combustion catalyst) and decomposed and removed. In the direct combustion method and heat storage combustion method, the treatment temperature is 700 to 850 ° C, whereas in the catalytic combustion method, the treatment temperature is as low as 350 to 450 ° C, so the auxiliary fuel cost can be reduced, and the nitrogen oxides accompanying combustion Since carbon monoxide is not produced as a by-product, it has been put into practical use in recent years.

Platinum-based catalysts are mainly used for VOC catalytic combustion, but metal catalysts such as nickel, cobalt, ruthenium, and palladium, and metal oxide catalysts such as ceria, titania, and zirconia are also used (for example, patent documents). 1).

Furthermore, a VOC removal filter in which a metal species having VOC combustion activity or a VOC adsorbent is attached to a heat-resistant inorganic fiber sheet-like substrate made of silica / alumina fibers and wound around a cylindrical wire mesh in a roll form is also known. (For example, Patent Document 2). At this time, the frequency of contact with the VOC can be adjusted by changing the size of the filter mesh and the number of windings on the wire mesh.

Japanese Patent Publication No. 8-24819 JP 2009-61433 A

However, in the conventional VOC removal method by catalytic combustion, the VOC combustion catalyst is filled into the VOC flow path of the exhaust equipment or the like, but there is a problem that the pressure loss increases and the processing efficiency decreases as the filling becomes dense. In addition, when the VOC flow path has a complicated shape, there is a concern that void loss and exhaust gas drift may occur during filling, further reducing the processing efficiency.

Further, with regard to the VOC removal filter described above, most of the inorganic fiber sheet-like base materials to which the metal species having VOC combustion activity and the adsorbent are attached are nonwoven fabrics. For this reason, when exhaust gas containing VOC is introduced, fluff is scattered by wind pressure, which may cause a malfunction of the VOC removal device. In addition, metal species or adsorbents with VOC combustion activity are also injected directly onto the sheet-like substrate, or the sheet-like substrate is impregnated in an aqueous dispersion of metal species or adsorbents with VOC combustion activity. Therefore, there is a concern that the metal species having the VOC combustion activity and the adsorbent adsorbent may be easily peeled off from the sheet-like substrate.

In view of the above circumstances, as a result of earnest research, by supporting a metal species having a high VOC combustion ability on a knitted fabric woven or knitted using a yarn made of an inorganic compound having high heat resistance (hereinafter referred to as inorganic fiber yarn), We have established a manufacturing technology for VOC-removed knitted fabrics (hereinafter referred to as VOC-removed knitted fabrics) that have high heat resistance, excellent flexibility, and little fluff scattering.

At this time, since the air permeability of the VOC-removed knitted fabric can be controlled by adjusting the yarn density during weaving or knitting, it is possible to suppress the pressure loss of the VOC passage and the drift of exhaust gas containing VOC. Moreover, since the strength and flexibility of the VOC-removed knitted fabric can be controlled by adjusting the fineness and the number of twists of the inorganic fiber yarn, it can be installed in a VOC flow path having a complicated shape. Furthermore, by coating the surface of the knitted fabric with a metal oxide, the metal supporting force and dispersibility are improved, and peeling can be suppressed.

That is, the present invention relates to (1) a knitted woven fabric carrying a metal species having a volatile organic compound combustion activity and a method for producing the same, or (2) a metal oxide. A volatile organic compound-removed knitted fabric having a volatile organic compound combustion activity supported on a knitted fabric coated on the surface, and a method for producing the knitted fabric, and (3) the yarn constituting the knitted fabric The material is characterized by containing at least one of basalt, silica, alumina, glass, carbon fiber, activated carbon fiber, hydrous aluminum silicate, potassium titanate, iron, copper, zinc, nickel, gold, silver, platinum. The volatile organic compound-removed knitted fabric according to (1) and (2) and a method for producing the same, and (4) the mesh size of the knitted fabric is 0.1 mm to 30 mm. The volatile organic compound-removed knitted fabric according to (1) and (2) and the method for producing the same, and (5) the metal species having the combustion activity of the volatile organic compound is nickel, cobalt, ruthenium, platinum, palladium The volatile organic compound-removed knitted fabric according to (1) and (2) and a method for producing the same, comprising at least one of ceria, zirconia, and titanium oxide (6) The metal oxide coated on the surface of the knitted fabric is composed of at least one of silica, alumina, and titania. The volatile organic compound-removed knitted fabric according to (2) and the method for producing the same It is said.

By using a knitted fabric made of inorganic fiber yarns, heat resistance is high, the strength is high, and scattering of fluff can be suppressed. In addition, many of the conventional VOC combustion catalysts are those in which active metal species are supported on pellets, powders, and granular carriers, but active metal species having VOC combustion ability are formed on the knitted fabric made of the knitted fabric of the present invention. By supporting it, the shape can be freely changed and it can be installed in VOC flow paths of factory exhaust equipment with complicated shapes.

A preferred embodiment of the present invention will be described. The embodiments described below do not limit the contents of the present invention described in the claims. In addition, all of the configurations described below are not necessarily essential requirements of the present invention.

(Material of inorganic fiber yarn)
The yarn materials used for knitted fabrics made of knitted fabric are basalt, silica, alumina, glass, carbon fiber, activated carbon fiber, hydrous aluminum silicate, potassium titanate, iron, copper, zinc, nickel, gold, silver, platinum Of these, it is preferable to contain at least one or more, more preferably at least one of basalt, silica, alumina, glass, iron, copper, zinc, nickel, basalt, silica, alumina Most preferably, at least one kind is contained. This is because basalt, silica, and alumina have high heat resistance, there is no concern about ignition, and yarns composed of these are put into practical use and easily available.

(Fineness of inorganic fiber yarn)
The fineness of the inorganic fiber yarn is preferably 20 to 2000 d (denier), more preferably 50 to 500 d, and most preferably 100 to 300 d. If it is less than 20d, the strength is low, and yarn breaks easily during weaving, knitting and active metal loading, and if it is thicker than 2000d, the strength is high, and there is a concern that the loom or knitting machine parts may be damaged during weaving or knitting. Because.

(Type of inorganic fiber yarn)
As the types of inorganic fiber yarns, both long fibers and short fibers can be used for VOC-removed knitted fabric, but long fibers are more preferable. This is because fluff is less likely to scatter in the case of long fibers compared to short fibers.

(Number of twists of inorganic fiber yarn)
The number of twists of the inorganic fiber yarn is preferably 20 T / m to 500 T / m, more preferably 100 T / m to 300 T / m, and most preferably 150 T / m to 200 T / m. If the number is less than 20 T / m, twisting is easy to unwind and there is a concern that sufficient strength cannot be maintained. If it is more than 500 T / m, twisting of the yarn is likely to occur, and weaving and knitting This is because not only is difficult, but the loom or knitting machine parts are easily damaged.

(Mesh size of knitted fabric made of inorganic fiber yarn)
The mesh size of the knitted fabric made of inorganic fiber yarns is preferably 0.1 mm to 10 mm, more preferably 0.3 mm to 1 mm, and most preferably 0.4 mm to 0.6 mm. This is because when the mesh size is less than 0.1 mm, sufficient air permeability cannot be secured, so the pressure loss of the VOC flow path becomes large, and when it is larger than 10 mm, the exhaust gas containing VOC is exhausted. This is because even when gas is introduced into the VOC-removed knitted fabric, the contact frequency between the VOC and the VOC-removed knitted fabric is low, and the VOC removal effect is low.

(Material of the yarn to cover the inorganic fiber yarn)
When weaving or knitting the inorganic fiber yarn, covering the inorganic fiber yarn with a yarn made of an organic polymer material in advance makes it easier to adjust the tension, and also prevents yarn breakage during weaving or knitting. At this time, the type of yarn used for the cover ring is preferably polyethylene terephthalate, nylon, polyethylene, polypropylene, acrylic, cotton, silk, wool, rayon or acetate, more preferably polyethylene terephthalate, nylon, polyethylene, polypropylene or acrylic, polyethylene terephthalate. And nylon are most preferred. This is because yarns of various finenesses are inexpensive and widely distributed and are easily available.

(Fineness of yarn used for covering)
The fineness of the yarn used for the covering is preferably 20 to 500d, more preferably 50 to 200d, and most preferably 75 to 150d. If it is less than 20d, the strength is low, and yarn breaks easily during covering, weaving or knitting. Also, if it is thicker than 500d, the thickness of the covering yarn is uneven, and the covering yarn is used during weaving or knitting. This is because it is difficult to adjust the tension.

(Number of windings of yarn used for covering onto inorganic fiber yarn)
The number of windings of the yarn used for the cover ring onto the inorganic fiber yarn is preferably 20 times / m to 300 times / m, more preferably 50 times / m to 250 times / m, 120 times / m to Most preferably, it is 150 times / m. When the number of windings is less than 20 turns / m, the effect of covering is hardly expected, and when it is more than 300 turns / m, the covering thread becomes thick, and the tension of the covering thread can be adjusted during weaving or knitting. This is because it becomes difficult.

(Weaving and knitting speed)
The weaving and knitting speed of the knitted fabric is preferably 10 to 500 pieces / min, more preferably 50 to 300 pieces / min, and most preferably 100 to 150 pieces / min. When the speed is slower than 10 yarns / min, the weft yarn tension becomes uneven and the knitted fabric is likely to wave (puckering). In addition, when it is faster than 500 yarns / min, the tension applied to the weft is large and the thread is easily broken. Alternatively, if the yarn is high strength, the yarn does not break and there is a concern that the loom and the knitted part may be damaged.

(Thread removal temperature for covering)
After weaving or knitting, the yarn used for the covering is removed by thermal decomposition. The removal temperature at this time is preferably 350 to 700 ° C, more preferably 400 to 600 ° C, and most preferably 450 to 550 ° C. If the temperature is lower than 350 ° C, there is a concern that the yarn used for the covering will not be thermally decomposed sufficiently, and if the temperature is higher than 700 ° C, there is no change in the thermal decomposition removal effect of the yarn used for the covering. This is because the yarn is likely to deteriorate.

(Type of metal oxide coating)
The metal oxide coating on the surface of the knitted fabric made of inorganic fiber yarn is preferably performed by a sol-gel method. At this time, the metal organic compound used contains at least one of the group consisting of tetraethoxysilane, tetraethoxytitanium, aluminum isopropoxide, zinc acetylacetonate, lead acetate, and barium oxalate. is there. Among them, tetraethoxysilane and aluminum isopropoxide are more preferable because they are converted to silicic acid and alumina which are generally used as industrial catalyst carriers by hydrolysis.

(Weight ratio of metal oxide coating the VOC-removed knitted fabric surface)
The weight ratio of the metal oxide coating the surface of the VOC-removed knitted fabric is preferably 0.1 to 30 wt.%, More preferably 1 to 10 wt.%, And most preferably 2 to 4 wt.% With respect to the VOC-removed knitted fabric. When the ratio of the metal oxide to the VOC-removed knitted fabric is less than 0.1 wt.%, The active metal tends to peel off and uniform loading becomes difficult, so there is a concern that the VOC removal ability may be reduced. On the other hand, if it exceeds 30 wt.%, The air permeability and flexibility of the knitted fabric are impaired, and there is a concern that the pressure loss will increase.

(Metal species with VOC combustion activity)
The metal species having VOC combustion activity preferably contains at least one of nickel, cobalt, ruthenium, platinum, palladium, ceria, zirconia, and titanium oxide. Nickel, cobalt, ruthenium, platinum, palladium Of these, it is more preferable to contain at least one of them, and it is most preferred to contain at least one of nickel, platinum, and palladium. This is because these metals are metal species with particularly high VOC resolution.

In addition, the metal which has VOC combustion activity may use single type among the above-mentioned thing, and may use it in mixture of 2 or more types.

Detailed examples are disclosed below. This is for the purpose of accurately showing the gist of the present invention, and the present invention should not be limited.

(Preparation of inorganic fiber yarn covered with polyester yarn)
In this example, basalt fiber yarn (made by Nippon Basalt Fiber, total fineness: 300d) obtained by injecting naturally occurring basalt into fine fibers was used. Moreover, polyester (PET) yarn (manufactured by Teijin Frontier, Superextor TW fineness: 150d, number of filaments: 72) was covered at 135 times / m on the basalt fiber yarn (hereinafter referred to as basalt fiber-PET yarn). . In addition, when using a thermogravimetric analyzer (TG-DTA 2000S) manufactured by Mac Science, the temperature of the basalt fiber-PET yarn was raised from room temperature to 900 ^o C at a temperature rise rate of 10 ^o C / min in an air atmosphere. As shown in FIG. 1, a 40% weight loss was observed by thermal decomposition of the PET yarn up to 500 ° C. After that, there was almost no change in weight up to 900 ° C.

(Weaving)
Basalt fiber-Weaving PET yarn using rapier loom (made by Itema Webbing, model number: ceramic special type) so that the number of driven yarns is 29 warp / inch and 28 weft / inch in the weft direction. A PET fabric was obtained. At this time, the mesh size was 1 mm square.

(Removal of PET fiber by pyrolysis)
The basalt fiber-PET fabric was heat-treated at 500 ° C. in the presence of air to remove the PET yarn to obtain a basalt fiber fabric.

(Silica coating of basalt fiber fabric by sol-gel method)
5 g of basalt fiber fabric was immersed in a mixed solution of 25 g of tetraethyl orthosilicate (special grade reagent, Wako Pure Chemical Industries, Ltd.), 37.6 g of ethanol, 23.5 g of distilled water and 0.3 g of hydrochloric acid, and air-dried at room temperature for 48 hours. Thereafter, heat treatment was performed at 500 ^° C. for 1 hour using an electric furnace to obtain a SiO ₂ -basalt fiber fabric.

(Supporting metals with VOC combustion activity)
After dissolving 2.7 g of Ni (NO ₃ ) ₂ · 6H ₂ O (special grade reagent, Wako Pure Chemical Industries) in 30 ml of a mixture of pure water and methanol in a volume ratio of 2: 1, SiO ₂ -basalt fiber 5 g of the woven fabric was immersed for 30 minutes at room temperature and normal pressure. After drying, it is heated in air at 500 ° C for 2 hours, and the precursor of SiO ₂ -basalt fiber fabric (hereinafter referred to as Ni (10) / SiO ₂ -basalt fiber fabric) in which nickel is supported at a rate of 10wt% Got the body.

(VOC decomposition experiment)
The reaction bed 1 is filled with 5.0 g of Ni (10) / SiO ₂ -basalt fiber fabric using a circulation reaction apparatus (total volume 312 ml) as shown in FIG. Was installed. After opening the valve 3, the valve 4 and the valve 5, the valve 6 was opened and the system was evacuated by the vacuum pump 7. After the valve 6 was closed, the pressure regulating valve 8 and the valve 9 were opened, and 250 Torr of hydrogen was introduced from the hydrogen cylinder 10 into the system. After closing the valve 3, the temperature of the reaction bed 1 was raised to 500 ° C. using the electric furnace 2, and the circulation pump 11 was operated to perform hydrogen reduction for 1 hour. After the valve 3 is opened and the circulation pump 11 is stopped, the valve 6 is opened, the inside of the system is evacuated by the vacuum pump 7, the valve 6 is closed again, and the pressure regulating valve 12 and the valve 13 are opened to enter the system. 30 torr of butane was introduced from the nC ₄ H ₁₀ (hereinafter referred to as butane) cylinder 14 into the system. Further, after closing the valve 13, the pressure regulating valve 15 and the valve 16 are opened, and 600 Torr of clean gas is introduced from a gas (clean gas) cylinder 17 in which N ₂ and O ₂ are mixed at a ratio of 4: 1 (inside the system) Oxygen / carbon (O / C) ratio = 1, butane-derived carbon concentration = 50000 ppmC). After the valve 16 was closed, the valve 3 was opened and the circulation pump 11 was operated to raise the reaction bed temperature to 400 ° C.

When sampling and analyzing the gas in the system, the pressure regulating valve 18 is opened, the valve 19 is opened, and argon gas is introduced from the argon gas cylinder 20 into the hydrogen ionization gas chromatograph detector 22 via the four-way cock 21. . Next, the valve 23 was opened and the gas reservoir 25 was evacuated by the vacuum pump 24. After the valve 23 was closed, the valve 26 was opened, and the gas in the system was introduced into the gas reservoir 25. Thereafter, the valve 26 was closed, the four-way cock 21 was rotated by 90 ° C., and the system gas introduced into the gas reservoir 25 was introduced into the hydrogen ionization gas chromatograph detector 22 together with the argon gas supplied from the argon gas cylinder 20. By such an operation, the gas in the system was sampled every predetermined time, the hydrocarbon was determined based on the C concentration in the circulation reaction system, and the combustion rate was determined by the following formula.

Formula 1

As a result, as shown in FIG. 3, the burning rate 60 minutes after the start of the experiment was 70.2%, and the butane-derived carbon concentration in the system was reduced to 15000 ppmC.

(VOC resolution evaluation of Ni / SiO ₂ -basalt fiber fabric)
From the above results, the VOC resolution evaluation of the Ni / SiO ₂ -basalt fiber fabric produced in this example was appropriate.

Preparation of a basalt fiber yarn covered with a polyester yarn, preparation of a basalt fiber fabric, and silica coating of a basalt fiber fabric by a sol-gel method were performed in the same manner as described in Example 1.

(Supporting metals with VOC combustion activity)
As described in Example 1, except that 4.1 g of Ni (NO ₃ ) ₂ · 6H ₂ O (special grade reagent, manufactured by Wako Pure Chemical Industries) was dissolved in 30 ml of a mixture of pure water and methanol in a volume ratio of 2: 1. A precursor of SiO ₂ -basalt fiber woven fabric (hereinafter referred to as Ni (15) / SiO ₂ -basalt fiber woven fabric) carrying nickel at a ratio of 15 wt% was obtained by the same method as described above.

(VOC decomposition experiment)
Experiments were performed in the same manner as described in Example 1 except that the reaction bed was filled with 5.0 g of Ni (15) / SiO ₂ -basalt fiber fabric using the circulating reaction apparatus shown in FIG. Further, the combustion rate was obtained by Equation 1.

As a result, as shown in FIG. 4, the combustion rate 60 minutes after the start of the experiment was 92.4%, and the butane-derived carbon concentration in the system was reduced to 3800 ppmC.

(VOC resolution evaluation of Ni (15) / SiO ₂ -basalt fiber fabric)
From the above results, the VOC resolution evaluation of the Ni / SiO ₂ -basalt fiber fabric produced in this example was appropriate.

Preparation of a basalt fiber yarn covered with a polyester yarn, preparation of a basalt fiber fabric, and silica coating of a basalt fiber fabric by a sol-gel method were performed in the same manner as described in Example 1.

(Supporting metals with VOC combustion activity)
As described in Example 1, except that 5.4 g of Ni (NO ₃ ) ₂ · 6H ₂ O (special grade reagent, manufactured by Wako Pure Chemical Industries) was dissolved in 30 ml of a solution in which pure water and methanol were mixed at a volume ratio of 2: 1. A precursor of SiO ₂ -basalt fiber woven fabric (hereinafter referred to as Ni (20) / SiO ₂ -basalt fiber woven fabric) carrying nickel at a ratio of 20 wt% was obtained by the same method as described above.

(VOC decomposition experiment)
The experiment was conducted in the same manner as described in Example 1 except that the reaction bed was filled with 5.0 g of Ni (20) / SiO ₂ -basalt fiber fabric using the circulating reaction apparatus shown in FIG. Further, the combustion rate was obtained by Equation 1.

As a result, as shown in FIG. 5, the burning rate 60 minutes after the start of the experiment was 99.2%, and the butane-derived carbon concentration in the system was reduced to 400 ppmC.

(VOC resolution evaluation of Ni (20) / SiO ₂ -basalt fiber fabric)
From the above results, the VOC resolution evaluation of the Ni / SiO ₂ -basalt fiber fabric produced in this example was appropriate.

Preparation of a basalt fiber yarn covered with a polyester yarn, preparation of a basalt fiber fabric, and silica coating of a basalt fiber fabric by a sol-gel method were performed in the same manner as described in Example 1.

(Supporting metals with VOC combustion activity)
Hexachloroplatinum (IV) acid hexahydrate (manufactured by Wako Pure Chemical Industries, Ltd.) 0.13 g was dissolved in 30 ml of a mixture of pure water and methanol at a volume ratio of 2: 1 and 5 g of SiO ₂ -basalt fiber fabric was immersed. . A 1M NaOH aqueous solution was added dropwise under a temperature condition of 50 ° C., and the mixture was stirred for 1 hour while adjusting the pH to 7.0, followed by vacuum drying. Thereafter, 250 ml of distilled water was added and the operation of stirring for 30 minutes was repeated three times, followed by vacuum drying again. Next, a precursor of SiO ₂ -basalt fiber woven fabric (hereinafter referred to as Pt (1) / SiO ₂ -basalt fiber woven fabric) baked in air at 500 ° C for 2 hours and loaded with platinum at a rate of 1wt% Got.

(VOC decomposition experiment)
Experiments were conducted in the same manner as described in Example 1, except that 5.0 g of Pt (1) / SiO ₂ -basalt fiber woven fabric precursor was charged into the reaction bed using the circulation reactor shown in FIG. . Further, the combustion rate was obtained by Equation 1.

As a result, as shown in FIG. 6, the burning rate 60 minutes after the start of the experiment was 99.9%, and the butane-derived carbon concentration in the system was reduced to 50 ppmC.

(VOC resolution evaluation of Pt (1) / SiO ₂ -basalt fiber fabric)
From the above results, the VOC resolution evaluation of the Pt (1) / SiO ₂ -basalt fiber fabric produced in this example was appropriate.

Comparative Example 1

Preparation of a basalt fiber yarn covered with a polyester yarn, preparation of a basalt fiber fabric, and silica coating of a basalt fiber fabric by a sol-gel method were performed in the same manner as described in Example 1.

(VOC decomposition experiment)
Experiments were conducted in the same manner as described in Example 1 except that 5.0 g of basalt fiber fabric was charged into the reaction bed using the circulation reaction apparatus shown in FIG. Further, the combustion rate was obtained by Equation 1 described in Example 1.

As a result, as shown in FIG. 7, the combustion rate 60 minutes after the start of the experiment was 0.0%, and no change was observed in the butane-derived carbon concentration in the system.

(Comprehensive evaluation of basalt fiber fabric)
From the above results, the VOC resolution evaluation of the basalt fiber fabric used in this comparative example was inappropriate.

Comparative Example 2

Preparation of a basalt fiber yarn covered with a polyester yarn, preparation of a basalt fiber fabric, and silica coating of a basalt fiber fabric by a sol-gel method were performed in the same manner as described in Example 1.

(VOC decomposition experiment)
Experiments were performed in the same manner as described in Example 1 except that 5.0 g of SiO ₂ -basalt fiber fabric was charged into the reaction bed using the circulating reaction apparatus shown in FIG. Further, the combustion rate was obtained by Equation 1.

As a result, as shown in FIG. 8, the combustion rate 60 minutes after the start of the experiment was 0.0%, and no change was observed in the butane-derived carbon concentration in the system.

(VOC resolution evaluation of SiO ₂ -basalt fiber fabric)
From the above results, the VOC resolution evaluation of the SiO ₂ -basalt fiber fabric used in this comparative example was inappropriate.

The results of VOC resolution evaluation performed in Examples 1 to 4 and Comparative Examples 1 and 2 are summarized in Table 1.

The VOC-removed knitted fabric of the present invention is used as a filter for removing VOC by installing it in an exhaust facility at a site where VOC is generated such as printing, painting, adhesion, and dry cleaning.

It is a figure showing the thermogravimetric curve of a basalt fiber-PET yarn. It is a figure which represents typically the circulating reaction apparatus used in VOC decomposition | disassembly experiment. Ni (10) / SiO ₂ - is a diagram showing over time the VOC resolution of basalt fiber fabric. Ni (15) / SiO ₂ - is a diagram showing over time the VOC resolution of basalt fiber fabric. Ni (20) / SiO ₂ - is a diagram showing over time the VOC resolution of basalt fiber fabric. Pt (1) / SiO ₂ - is a diagram showing over time the VOC resolution of basalt fiber fabric. It is a figure which shows the VOC resolution | decomposability of a basalt fiber fabric over time. SiO ₂ - is a diagram showing over time the VOC resolution of basalt fiber fabric.

1 ... Reaction bed of a circulating reactor,
2 ... Electric furnace,
3-6 ... Valve,
7 ... Vacuum pump,
8 ... Pressure regulating valve,
9 ... Valve,
10 ... Hydrogen cylinder,
11… Circulating pump of circulating reactor,
12 ... pressure regulating valve,
13… Valve,
14 ... Butanbomb,
15 ... pressure regulating valve,
16 ... Valve,
17 ... Clean gas cylinder,
18 ... pressure regulating valve,
19… Valve,
20… Argon gas cylinder,
21 ... Four-way cock,
22 ... Hydrogen ionization gas chromatograph detector,
23… Valve,
24 ... Vacuum pump,
25 ... Gas reservoir,
26… Valve

Claims (6)

A volatile organic compound-removed knitted fabric characterized by carrying a volatile organic compound combustion activity on the knitted fabric, and a method for producing the same. A volatile organic compound-removed knitted fabric having a metal oxide having a combustion activity of a volatile organic compound supported on a knitted fabric having a metal oxide coated on the surface, and a method for producing the same. The material of the yarn constituting the knitted fabric is at least one of basalt, silica, alumina, glass, carbon fiber, activated carbon fiber, hydrated aluminum silicate, potassium titanate, iron, copper, zinc, nickel, gold, silver, platinum The volatile organic compound-removed knitted fabric according to claim 1 and a method for producing the same. 3. The volatile organic compound-removed knitted fabric according to claim 1 and a method for producing the knitted fabric, wherein the knitted fabric has a mesh size of 0.1 mm to 30 mm. The metal species having a combustion activity of a volatile organic compound is composed of at least one of nickel, cobalt, ruthenium, platinum, palladium, ceria, zirconia, and titanium oxide. 2. The volatile organic compound-removed knitted fabric according to 2, and a production method thereof. 3. The volatile organic compound-removed knitted fabric according to claim 2, wherein the metal oxide coated on the surface of the knitted fabric comprises at least one of silica, alumina, and titania.