KR100787118B1 - A zeolite adsorbent to remove harmfull gases released from elestomer, and a method of prepairing the same - Google Patents

Abstract

An adsorbent for removing harmful gases of rubber and a method of preparing the same are provided to adsorb and remove effectively harmful gases generated from rubber, be effectively used in the preparation of an environmentally friendly rubber composite material from which harmful gases are not released, and which has various colors when the adsorbent is used in a rubber material preparation process. A zeolite adsorbent for removing harmful gases of rubber comprises: a hydrogen ion exchanged zeolite in which at least one zeolite selected from the group consisting of ZSM-5, mordenite, and beta zeolite is ion exchanged with hydrogen; a metal oxide supported zeolite in which a metal oxide is supported onto the hydrogen ion exchanged zeolite; or a mixture thereof. The hydrogen ion exchanged zeolite is treated with at least one selected from the group consisting of ammonium nitrate, ammonium chloride, ammonium acetate, nitric acid, sulfuric acid, and hydrochloric acid. The hydrogen ion exchanged zeolite has a specific surface area of 300 to 650 m^2/g. The metal oxide is at least one metal oxide selected from the group consisting of nickel oxide(NiO), cupric oxide(CuO), cobalt oxide(CoO), and ferric oxide(Fe2O3). The metal oxide is supported onto the hydrogen ion exchanged zeolite in an amount of 0.1 to 30% by weight based on the total weight of the metal oxide supported zeolite.

Description

Zeolite adsorbent for removing harmful gas of rubber, and its manufacturing method {A ZEOLITE ADSORBENT TO REMOVE HARMFULL GASES RELEASED FROM ELESTOMER, AND A METHOD OF PREPAIRING THE SAME}

The present invention provides a rubber harmful for simultaneously removing acid, neutral, and basic harmful gases released from a rubber material by using ZSM-5, mordenite, beta zeolite, ion-exchanged with hydrogen, and an adsorbent in which a transition metal oxide is supported on these adsorbents. It relates to a gas adsorbent.

In the early days of industrialization, environmental pollution such as air and water has been a serious problem, but recently, due to the damage caused by indoor pollution such as sick house syndrome, preparations for this are becoming more serious. Therefore, in order to improve indoor air quality, countries around the world have enacted and implemented environmental standards for indoor polluted air. Since 2003, Korea has enacted the Indoor Air Quality Control Act for multi-use facilities, which has strengthened legal regulations on the emission of harmful gases. In order to cope with such regulations, research on building materials without harmful gases is being actively conducted.

In construction rubber materials, which are widely used in window frames and flooring materials, volatile organic compounds (VOCs) and odorous substances such as sulfur compounds and amine compounds, which are highly unpleasant, are emitted simultaneously, contaminating indoor air. It is the cause. Therefore, for the purification of indoor air, it is necessary to develop a building rubber material that does not emit harmful gas through the combination of an adsorbent and a rubber material that can effectively remove the harmful gas emitted from the rubber material. In order to develop such an affinity rubber material, development of an adsorbent capable of simultaneously adsorbing and removing various kinds of harmful gases emitted from the rubber material should be preceded. There is not much research on the type and concentration of gas.

Generally, activated carbon and activated carbon fibers are mostly used as adsorption materials for purifying indoor air. Activated carbon and activated carbon fibers with a large specific surface area are widely used as filters for air cleaners because they can effectively remove harmful gases such as volatile organic compounds that cause sickness syndrome and odors emitted from refrigerators. Korean Patent No. 0509854 discloses a method of preparing a deodorant which removes odor generated in a refrigerator such as ammonia and methyl mercaptan by using carbon nanoballs impregnated with a transition metal compound and potassium iodide as an adsorbent. 0550517 discloses an air purifier that manufactures a filter filled with activated carbon fibers to remove dust and odor generated in various industrial facilities, restaurants, and homes. However, in the case of activated carbon, despite the excellent adsorptive power of harmful gases, it is only applicable to the production of black rubber materials when manufacturing eco-friendly rubber materials due to the color of activated carbon. However, with the recent improvement of living standards and emphasis on aesthetics for buildings, various colors of rubber materials are required. When activated carbon is used to manufacture eco-friendly rubber materials by combining rubber materials and adsorbents, white rubber or other colored materials are used. It has the disadvantage that rubber manufacturing is impossible. Therefore, it is necessary to develop an adsorbent capable of manufacturing eco-friendly rubber materials of various colors.

In order to manufacture eco-friendly rubber materials of various colors, adsorbents that can effectively remove harmful gases emitted from rubber materials as white or off-white adsorbents are needed. Korean Patent Nos. 0413243 and 0424788 describe a method for preparing an adsorbent that can adsorb odors and volatile organic compounds released from a polymer material using bentonite activated by an acidic solution. Acid-treated bentonite is off-white and may be suitable for manufacturing eco-friendly rubber materials of various colors.

However, the activated bentonite adsorbent does not have high adsorption capacity for basic gas or acid gas depending on the type of metal cation. In addition, the adsorption power test of the adsorbent to the harmful gas is carried out on a single gas, it is not known whether the performance of the adsorbent is appropriate in the rubber material that is released by mixing various harmful gases. This is because when the acid, neutral, and basic gases are mixed and released like a rubber material, the same adsorbent may exhibit different adsorption power than when the adsorption performance is tested by a single gas. In fact, M.A. The report of Lillo-Rodenas discloses that the same VOCs system has a difference in adsorption power when adsorbed to the adsorbent as a single gas and when adsorbed to the adsorbent as a mixed gas (Carbon, Vol. 44, p. 1455). , 2006). Therefore, it is necessary to develop a white or off-white adsorbent having excellent adsorption power even in the presence of various kinds of harmful gases.

The present invention is to acid-treated ZSM-5, mordenite, Beta zeolite of white system ZSM-5, mordenite, to supplement the disadvantages of the above-mentioned conventional adsorbents and to develop eco-friendly rubber materials of various colors Beta zeolite was prepared, and its purpose is to prepare an adsorbent that can be effectively adsorbed and removed at the same time in a state in which harmful gases generated from rubber materials are mixed by supporting transition metal oxides in these adsorbents.

The present invention to achieve the above object is a hydrogen ion exchange zeolite ion-exchanged at least one zeolite selected from the group consisting of ZSM-5, mordenite, and Beta zeolite with hydrogen; A metal oxide-supported zeolite in which a metal oxide is supported on the hydrogen ion exchange zeolite; Or a rubber harmful gas adsorbent comprising a mixture of two or more thereof.

The present invention also includes at least one zeolite selected from the group consisting of ZSM-5, mordenite, and Beta zeolite, and at least one selected from the group consisting of ammonium nitrate, ammonium chloride, ammonium acetate, nitric acid, sulfuric acid, and hydrochloric acid. It provides a method for producing a rubber harmful gas adsorbent comprising the step of preparing a hydrogen ion exchange zeolite by treating with an acidic solution to dry.

In the present invention, as the raw material of the adsorbent, ZSM-5, mordenite, Beta zeolite having nano pores and a large specific surface area were used, and more preferably ZSM- having a specific surface area of 300 to 650 m ² / g. 5, mordenite, Beta zeolite was used.

In addition, although the raw materials are well developed pores and excellent performance as an adsorbent by itself, surface treatment processes such as hydrogen ion exchange and transition metal oxide support to effectively treat various types of harmful gases emitted from rubber materials at the same time. It is more preferable to prepare the adsorbent through.

Hydrogen ion exchange is preferably acid treated with at least one acid selected from the group consisting of ammonium nitrate, ammonium chloride, ammonium acetate, nitric acid, sulfuric acid, and hydrochloric acid.

In addition, in order to increase the adsorption capacity for various harmful gases emitted from the rubber material, nickel ions (NiO), copper oxides (CuO), cobalt oxides (CoO), and iron oxides (Fe ₂ O ₃ ) were added to the zeolite exchanged with hydrogen ions. It is more preferable to use an adsorbent carrying at least one transition metal oxide selected from the group consisting of:

In general, rubber materials commonly used for window frame rubber, home appliances, gaskets, and indoor flooring materials include EPDM rubber, SBR rubber, and NR rubber. These rubber materials include acid gases such as carbon disulfide and hydrogen sulfide, toluene, di (ethylene glycol) butyl ether, 2,6-di-tert-butyl-4-methyl phenol, and 2,4-dioctyl at high temperatures of 90 ° C. or higher. Various types of harmful gases are detected, such as neutral gases such as phenol, tetradecane, hexadecane, eicosane, norbornene, and basic gases such as diethylamine, dibutylamine and cyclohexylamine. However, since the concentration of polluting gases released is low (mostly 50 ppm or less), it is very difficult to effectively remove these harmful gases.

Accordingly, in the present invention, a hydrogen ion-exchanged zeolite obtained by ion-exchanging at least one zeolite selected from the group consisting of ZSM-5, mordenite, and beta zeolite with hydrogen, or a metal in which a transition exclusive oxide is supported on the hydrogen ion exchange zeolite Oxide-supported zeolite is used as an essential component of the rubber harmful gas adsorbent.

The hydrogen ion exchange zeolite may be prepared by adding ZSM-5, mordenite, or Beta zeolite to an acidic solution, stirring at 70 to 90 ° C. for a sufficient time, followed by filtration and washing with water. It is preferable to perform a filtration and a water washing process 3 times or more. After the treatment is completed, it may be used as a rubber harmful gas adsorbent through a drying process.

At this time, the acid used in the acid treatment of the zeolite is ammonium nitrate, ammonium chloride, ammonium acetate, nitric acid, sulfuric acid, hydrochloric acid and the like, a mixture of two or more of these may be used. The concentration of the acidic solution is preferably 0.1 to 1N, the weight ratio of the zeolite and the acidic solution is preferably in the ratio of 1:10 to 1:20.

In addition, the transition metal oxide supported adsorbent is preferably prepared by the impregnation method using a metal salt containing at least one transition metal selected from the group consisting of nickel, copper, cobalt, and iron, the metal salt is nitrate , At least one selected from the group consisting of sulfates, and chlorides. The hydrogen ion exchange zeolite was added to an aqueous solution in which the compound containing the transition metal was dissolved in water in a desired amount, stirred, and then dried using a rotary vacuum evaporator.

The dried adsorbent may be prepared by firing at a temperature of 400 to 700 ° C. in an oxygen atmosphere to prepare ZSM-5, mordenite, and beta zeolite adsorbent on which a transition metal oxide is supported. The firing time is not particularly limited so that sufficient firing can be achieved, but may be preferably performed by a method for 4 to 8 hours.

As the type of transition metal oxide supported on the adsorbent, one or more transition metal oxides selected from nickel oxide (NiO), copper oxide (CuO), cobalt oxide (CoO), and iron oxide (Fe ₂ O ₃ ) may be supported. Can be.

In the supported amount of the transition metal oxide, the content of the transition metal oxide supported on the adsorbent is preferably 0.1 to 30% by weight, more preferably 1 to 10% by weight. If the content is less than 0.1% by weight, the adsorption effect of harmful gases according to the transition metal oxide is insignificant, and if it exceeds 30% by weight, the pores of the adsorbent are blocked by the transition metal oxide, which decreases the ability to adsorb harmful gases. not.

ZSM-5, mordenite, beta zeolite and the adsorbent in which the transition metal oxide is supported on these adsorbents prepared by the present invention are carbon sulfides having acidic properties, volatile organic compounds having neutral properties, As an adsorbent that can effectively adsorb amines having basic properties and the like at the same time, it can be effectively used for removing various kinds of harmful gases emitted from rubber materials. In particular, ZSM-5, mordenite, Beta zeolite ionized with hydrogen and rubber adsorbents for removing harmful metals in which the transition metal oxides are supported on these adsorbents can be used as substitutes for reinforcement in the manufacturing process of rubber materials. By blocking the odor emitted from the rubber material in the process during the process, not only harmful gases are released, but also has the advantage of manufacturing an environmentally friendly rubber material having a variety of colors.

In particular, the rubber harmful gas adsorbent of the present invention has a toluene adsorption removal rate of 90% or more, a cyclohexylamine adsorption removal rate of 95% or more, and carbon disulfide based on a mixed gas containing 50 ppm of toluene and 50 ppm of cyclohexylamine. The adsorption removal rate for the sole gas (100 ppm basis) was mostly 75% or more, indicating a relatively high harmful gas removal rate.

Hereinafter, preferred examples are provided to help understanding of the present invention, but the following examples are merely to illustrate the present invention, and the scope of the present invention is not limited to the following examples.

Experimental Example 1 (Rubber harmful gas component analysis)

In order to identify the types of harmful gases emitted from EPDM rubber, SBR rubber, and NR rubber, the rubber materials were each mounted in an empty column, and heated to 90 ° C. to collect the harmful gases emitted from the rubber materials. Hazardous gases emitted from rubber materials are low in concentration, so for the purpose of accurate analysis, harmful gases are collected and concentrated for 1 hour with liquid nitrogen, which is then heated to produce hazardous gases, TD-GC-MS (Thermal Desoption Gas Chromatograph Mass Spectrometer). ) To be injected.

Examples of harmful gases detected by this method include acidic gases such as carbon disulfide and hydrogen sulfide, toluene, di (ethylene glycol) butyl ether, 2,6-di-tert-butyl-4-methyl phenol, and 2,4-di. Various types of harmful gases have been detected, such as neutral gases such as octylphenol, tetradecane, hexadecane, eicosane, norbornene, and basic gases such as diethylamine, dibutylamine and cyclohexylamine.

Example 1

20 g of ZSM-5 having a 400 m ² / g specific surface area was added to 200 g of 0.5 N ammonium nitrate aqueous solution, stirred at 70 ° C. for 12 hours, filtered, and washed with water until the pH became neutral.

Adsorbent prepared by adding washed ZSM-5 to 200 g of 0.5 N ammonium nitrate aqueous solution and repeating the acid treatment twice in the same manner as in the previous method, and then finally washing the washed powder at a temperature of 110 ° C. for 12 hours. Was used as an adsorbent to remove harmful gases released from rubber materials.

Example 2

An adsorbent was prepared in the same manner as in Example 1 except that mordenite having a specific surface area of 500 m ² / g was used.

Example 3

An acid treated adsorbent was prepared in the same manner as in Example 1 except that Beta-Zeolite having a specific surface area of 620 m ² / g was used.

Comparative Example 1

Na-ZSM-5 (Zeochem Co., Ltd.) was used as an adsorbent to remove harmful gases released from rubber materials.

Comparative Example 2

Commercially available Na-mordenite (Zeochem) was used as an adsorbent to remove harmful gases released from rubber materials.

Comparative Example 3

Na-Beta Zeolite (Zeochem Co., Ltd.) was used as an adsorbent to remove harmful gases emitted from rubber materials.

Example 4

Nickel nitrate 4.33 g was impregnated in 10 g of ZSM-5 ion-exchanged with hydrogen in Example 1, and then dried at 110 ° C. for 12 hours.

After the drying step, the dried nickel nitrate-supported ZSM-5 was calcined at 550 ° C. for 5 hours while flowing a predetermined amount of air to prepare a metal oxide-supported zeolite having a supported amount of nickel oxide of 10% by weight.

Example 5

1.60 g of copper nitrate was impregnated in 10 g of H-mordenite ion-exchanged with hydrogen in Example 2, followed by drying at 110 ° C. for 12 hours.

After the drying step, the dried copper nitrate-supported H-mordenite was calcined at 550 ° C. for 5 hours while flowing a predetermined amount of air to prepare a metal oxide-supported zeolite having a supported amount of copper oxide of 5% by weight.

Example 6

In Example 3, 104 g of beta zeolite ion-exchanged with hydrogen was impregnated with cobalt nitrate 2.04 g, and then dried at 110 ° C. for 12 hours.

After the drying process, the dried cobalt nitrate-supported beta zeolite was calcined at 550 ° C. for 5 hours while flowing a predetermined amount of air to prepare a metal oxide-supported zeolite having a supported amount of cobalt oxide of 5% by weight.

Example 7

In Example 1, 1.33 g of iron nitrate was impregnated in 10 g of ZSM-5 ion-exchanged with hydrogen, and then dried at 110 ° C. for 12 hours.

After the drying process, the dried iron nitrate-supported ZSM-5 was calcined at 550 ° C. for 5 hours while flowing a predetermined amount of air to prepare a metal oxide-supported zeolite having a loading amount of iron oxide of 5% by weight.

Experimental Example 2 (Evaluation of rubber harmful gas adsorption capacity)

In order to measure the adsorption removal rate of the adsorbent to the harmful gas released from the rubber material, a harmful gas of a constant concentration was prepared. Hazardous gases were mixed with 50 ppm of toluene and cyclohexylamine released through the heating of the rubber material to a total concentration of 100 ppm.

Carbon disulfide reacted with cyclohexylamine and mixed with each other to produce a white solid. Adsorption performance was evaluated at 100 ppm concentration without mixing.

0.2 g of the adsorbents according to Examples 1 to 7 were added to 1 L of the tether bag, 0.6 L of the harmful gas to be evaluated was injected into the tether bag, and the noxious gas was adsorbed and removed for 2 hours. The adsorption performance of each sample was investigated.

Table 1 shows the adsorption removal rate for the harmful gas released from the rubber material evaluated through Examples and Comparative Examples of the present invention.

division Toluene (50 ppm) Cyclohecylamine (50 ppm) Carbon disulfide (100 ppm) Example 1 97 100 90 Example 2 92 95 50 Example 3 95 100 75 Comparative Example 1 65 90 85 Comparative Example 2 60 85 54 Comparative Example 3 72 88 60 Example 4 100 100 95 Example 5 98 100 92 Example 6 95 100 78 Example 7 100 100 87

As shown in Table 1, the commonly used Na ion exchange zeolite showed lower adsorption performance of toluene, cyclohexylamine and carbon disulfide than the embodiment of the present invention.

The adsorbents according to the present invention showed excellent adsorption removal rates for all acidic, basic, and neutral harmful gases. In particular, the ZSM-5 adsorbents ion-exchanged with hydrogen had a removal efficiency of toluene, cyclohexylamine and carbon disulfide of 95% or more. As it shows very good adsorption of harmful gases, it is suitable as an adsorbent for removing harmful gases generated from rubber materials.

As described above, according to the present invention, ZSM-5, mordenite, Beta zeolite adsorbent and hydrogenated ion-exchanged ZSM-5, mordenite and Beta zeolite adsorbent are used to generate the rubber. Adsorption / removal of harmful gases can be effectively carried out, and the adsorbent can be effectively used to manufacture eco-friendly rubber composite materials having various colors without releasing harmful gases when used in combination with the adsorbent in the manufacturing process of rubber materials. Have

Claims (10)

Hydrogen ion exchange zeolites in which at least one zeolite selected from the group consisting of ZSM-5, mordenite, and Beta zeolite is ion exchanged with hydrogen; A metal oxide-supported zeolite in which a metal oxide is supported on the hydrogen ion exchange zeolite; or Mixtures of two or more of these Rubber harmful gas adsorbent comprising a. The rubber harmful gas adsorbent according to claim 1, wherein the hydrogen ion exchange zeolite is treated with one or more selected from the group consisting of ammonium nitrate, ammonium chloride, ammonium acetate, nitric acid, sulfuric acid, and hydrochloric acid. The rubber hazardous gas adsorbent of claim 1, wherein the hydrogen ion exchange zeolite has a specific surface area of 300 to 650 m ² / g. The rubber hazardous material according to claim 1, wherein the metal oxide is at least one metal oxide selected from the group consisting of nickel oxide (NiO), copper oxide (CuO), cobalt oxide (CoO), and iron oxide (Fe ₂ O ₃ ). Gas adsorbent. The rubber harmful gas adsorbent of claim 1, wherein the metal oxide is supported by 0.1 to 30% by weight based on the total weight of the metal oxide-supported zeolite. At least one zeolite selected from the group consisting of ZSM-5, mordenite, and Beta zeolite is an acidic solution containing at least one selected from the group consisting of ammonium nitrate, ammonium chloride, ammonium acetate, nitric acid, sulfuric acid, and hydrochloric acid. A process for preparing a rubber harmful gas adsorbent comprising treating and drying to prepare a hydrogen ion exchange zeolite. The method of claim 6, wherein the acid solution has a concentration of 0.1 to 1 N, and the mixing ratio of the zeolite and the acid solution is 1:10 to 1:20 by weight. The method of claim 6, wherein the acidic solution treatment is carried out three or more times of mixing, stirring, filtering, and washing the zeolite and the acidic solution, wherein the stirring temperature is 70 to 90 deg. Manufacturing method. The method according to any one of claims 6 to 8, wherein the metal salt containing at least one selected from the group consisting of nickel, cobalt, copper, and iron is supported on the hydrogen ion exchanged zeolite, and then fired. Rubber harmful gas adsorbent manufacturing method further comprising. 10. The method of claim 9, wherein the firing step is a rubber harmful gas adsorbent for heat treatment at 400 to 700 ℃ for 4 to 8 hours.