JPS6168135A - Agent for removing carbon monoxide in tobacco smoke - Google Patents

Abstract

PURPOSE:To obtain a CO-removing agent capable of reducing remarkably CO in smoke without deteriorating the flavor of tobacco smoke by using a mixed composition of metallic oxides and activated carbon as a carrier, and depositing a Pd salt and a copper salt on the carrier. CONSTITUTION:A mixture of a Pd salt and a copper salt is deposited on a carrier consisting of a mixed composition of metallic oxides and activated carbon. A material contg. >=1 kind selected from a group consisting of MgO, Al2O3, SiO2, P2O5, or transition metal oxides (e.g., CuO) is used as said metallic oxides. Besides, said metallic oxide is a silicate ore contg. >=1 kind between MgO or Al2O3 in the composition, and kaolinite and zeolite can be exemplified. In this case, the amt. of the metallic oxide to be contained in the mixed composition of activated carbon and metallic oxides is preferably regulated to 10-90wt%. By this CO-removing agent thus obtained, CO in smoke can be remarkably reduced without deteriorating the flavor of the tobacco smoke.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides the following advantages:
This invention relates to a remover that selectively removes carbon monoxide from tobacco smoke generated during smoking.

(Industrial Application Field) In general, carbon monoxide (hereinafter simply referred to as CO), which is generated by incomplete combustion of carbon and carbon-containing compounds, binds tightly to hemoglobin in the blood and inhibits oxygen absorption and transport in the blood. Because it significantly impedes the function of the drug, it can cause acute poisoning symptoms such as headache and dizziness, and in extreme cases, it can lead to death. Furthermore, long-term exposure to CO is said to cause chronic heart disease.

This CO is also contained in several percent of the smoke that smokers directly inhale when they smoke cigarettes, so-called mainstream smoke.
Although this is greatly diluted by the air that is simultaneously inhaled before reaching the lungs of the human body, it is thought to contribute to the chronic concentration of CO-bound hemoglobin in the blood of smokers.
It is desired to reduce CO from tobacco smoke.

(Prior Art) Conventionally, from this point of view, CO'b'lJ in mainstream cigarette smoke has been
Many attempts have been made to reduce the degree of damage, and many proposals have been made in patent specifications and the like.

These proposals can be broadly classified as follows.

1) A method of selecting and using raw materials that generate less Co.

2) A method of suppressing the production of CO by providing holes in a portion of the filter or using a wrapping paper with high porosity, or reducing the generated CO by diffusion from the wrapping paper.

3) Fill or hold an oxidation catalyst, oxidizer, or adsorbent in a part of the filter or cigarette holder, etc. to reduce CO
A method of reducing it by oxidizing or capturing it.

Among the methods 1) to 3) above, methods 1) and 2) have been extensively studied to date, and some of them have been commercialized.

However, as for method 3), no definitively effective method has yet been found. The reasons for this are that the contact time between tobacco smoke and the oxidation catalyst and other fillers is extremely short, that inhibiting components such as moisture and tar coexist in the surrounding environment, and that consideration must be given to the toxicity of the fillers themselves. In addition to the necessity, there are many other problems, such as the fact that the aroma and taste of cigarettes is impaired.

Examples of substances that have been proposed for the purpose of reducing CO in tobacco smoke by method 3) include the so-called hopkalift-based composite oxide catalyst (Japanese Unexamined Patent Application Publication No. 51/1982), which is mainly composed of a composite of copper oxide and manganese oxide. -72988, JP-A-53
-96399) and metal oxide catalysts such as manganese oxide (Br1t, Pat.

No. 1315374), but all of them suffer from significant deactivation due to moisture, and follow-up tests show almost no removal effect. In addition, there are many disclosures regarding precious metal supported catalysts (JP-A-55-73344, JP-A-53-149192, JP-A-55).
-137039), but as a result of additional tests, CO in smoke
It has become clear that no sufficient effect can be expected in the removal of .

However, on the other hand, it was developed for the purpose of synthesizing acetaldehyde using ethylene as a raw material and using oxygen in the gas phase.
The so-called Wacker type catalyst is highly active for CO oxidation, and also effectively incorporates water into the redox system and oxidizes CO using oxygen in the gas phase.
A mechanism has been proposed to oxidize O (Journal Air Pollution Control Association).
ol As5oc, ) 2 B, 253 (1978))
.

This Wachker type catalyst basically uses PdX2 or M2 PdX2 (X is a halogen atom, M is a group Ia metal in the periodic table) as an active compound for the substrate,
Moreover, CuX2 (X is a halogen atom) is used as a redox pair for this.

The presence of moisture, which is generally considered undesirable in low-temperature CO oxidation using metal oxides, works effectively in this type of catalyst, so under humid conditions such as the low range of CO in cigarette smoke. It can be said to be an excellent catalyst for use in

In the invention using such a Wasoker-type catalyst for reducing CO, copper salts other than copper halides (mainly copper nitrate) are added as a third component in order to promote reoxidation of palladium salts reduced by CO. How to increase activity by adding as
(Japanese Unexamined Patent Publication No. 50-33990) and an example in which tin ions are added to promote reoxidation (Japanese Unexamined Patent Publication No. 54-11).
No. 0400), and an example in which a monovalent copper salt was coexisting (Japanese Patent Application Laid-Open No. 55-97252). The Varaker-type catalysts seen in these inventions related to cO oxidation can be used as homogeneous catalysts in the form of solutions or as heterogeneous catalysts supported on various carriers such as alumina, silica, aluminosilicate, molecular sieves, and activated carbon. There is.

However, the catalyst in which the Waraker-type catalyst according to the conventional invention is supported on the above-mentioned carrier, which is known as a catalyst carrier,
When used for the purpose of reducing CO in mainstream tobacco smoke, the effect is not necessarily sufficient; on the other hand, when T-alumina is used as a carrier, the oxidation activity of co is high;
Although the reduction rate of CO in tobacco smoke is extremely high when it is partially filled in a cigarette filter, it has the disadvantage that it significantly reduces the aroma and taste of tobacco smoke. This is considered to be due to the physical and chemical properties of the γ-alumina surface. In addition, when activated carbon alone is used as a carrier, although no adverse effect on the taste of Taboko was observed, there is a drawback that a sufficient CO reduction effect cannot be obtained.

[Problem that the invention seeks to solve]

The present invention was made in view of the above-mentioned problems of conventional CO reduction catalysts, and provides a CO removal agent that is highly effective in reducing C○ in tobacco smoke and does not adversely affect the aroma and taste of tobacco smoke. The purpose is to provide.

When actually applying a CO remover to tobacco, mainly cigarettes, it is necessary to hold the CO oxidation catalyst constituting the CO remover on a carrier and fill it into a cigarette filter or holder. Therefore, the present inventors investigated in detail the relationship between the type of carrier on which the catalyst should be supported and the oxidation activity of CO, and the effect on the aroma and taste of tobacco smoke regarding the Varaka type catalyst consisting of a combination of palladium salt and copper salt. As a result of research, the inventors discovered that a highly active CO removal catalyst that does not adversely affect the aroma and flavor can be obtained when a mixed composition of metal oxides and activated carbon is used as a carrier, leading to the present invention. .

[Means for solving problems]

That is, the present invention is a carbon monoxide remover in tobacco smoke, characterized in that a mixture of a palladium salt and a copper salt is supported on a carrier made of a mixed composition of a metal oxide and activated carbon.

In the present invention, the activated carbon used as a carrier composition is not particularly limited, and vegetable activated carbon or coal-based activated carbon such as coconut shell charcoal, palm charcoal, and softwood charcoal is preferably used. Further, it is desirable that these activated carbons have a specific surface area of about 500 to 1300 m/g as determined by B, E, and T measurement methods.

Next, as metal oxides mixed with activated carbon, magnesium oxide (MgO), aluminum oxide (A12O
3) A metal oxide containing one or more selected from the group consisting of silica (Si02), phosphorus pentoxide (P2O3), and transition metal oxides, or a silicate containing one or more of magnesium or aluminum in its composition. Minerals such as kaolinite (A1203 ・2SiO□ ・2H20), asbestos (Mgo-3io2), sepiolite (Mgg H2
(Si4011)3 ・3H20), zeolite (Na
2 A12S 1301o-XH20), diatomaceous ±
(Si02 is the main component, A 1203 , F
Contains e2O3, MgO, and CaO. ) etc. are preferred.

Further, as the transition metal oxide, for example, copper oxide (Cub
), zirconium oxide (ZrO2), titanium oxide (T
i O□), nickel oxide (Nip), cobal oxide)
(Co 2 O) etc. can be suitably used.

Next, any known method may be used to solidify the activated carbon and the metal oxide to form a carrier. For example, activated carbon powder and total oxide powder may be mixed in an aqueous solution of a water-soluble polymer such as polyvinyl alcohol, silica sol, alumina sol, or water glass. Methods such as kneading and hardening the mixture, forming it into particles of about 20 to 60 meshes, pre-drying, and then heat-treating at a temperature of about 100° C. or higher may be employed.

In this case, the amount of metal oxide contained in the mixed composition of activated carbon and metal oxide is preferably 10 to 90% by weight, more preferably 30 to 70% by weight.

Next, the supported amount of the catalyst component contained in the CO removing agent of the present invention is 0.01 to 0.2 for palladium salts.
The range of m mol/g is good, and 0 for copper salts.
．． 1-2.0 mmol/g, preferably 0.4-2.0 mmol/g
A range of 1°0 mmol/g is preferable. Furthermore, as types of palladium salts and copper salts, chlorides, nitrates, sulfates, etc. can be used.

As a method for supporting the above-mentioned metal salt catalyst on a mixed composition carrier of metal oxide and activated carbon, the pore volume of the carrier is measured in advance using the B, E, T method, etc., and the volume is approximately equal to that of the carrier. The so-called bore filling method involves dissolving a palladium salt and a copper salt in a volume of water and absorbing the entire amount into the pores of the carrier, or by immersing the carrier in a mixed aqueous solution of a palladium salt and a copper salt, and then using a rotary evaporator, etc. It is possible to apply a method such as the so-called impregnation method, in which the solution is concentrated and the salts are precipitated onto the carrier using It is excellent because it does not require any restrictions.

The CO remover of the present invention prepared as described above is used by filling a portion of a cigarette filter or a cigarette holder.

The present invention will be explained in more detail with reference to Examples below. By using the CO remover of the present invention, it is possible not only to significantly reduce C○ in tobacco smoke, but also to improve the aroma and flavor of tobacco smoke. It has been found that it does not have any negative effects on smoke, but rather has excellent effects such as reducing the irritation caused by smoke.

(Example) (1) Preparation of carrier First, six types of catalyst carriers A to F according to the present invention made of a mixed composition of metal oxide and activated carbon were prepared by the following method.

Preparation Example 1 Coconut husk charcoal pulverized to a particle size of 200 mesosius or less
After sufficiently mixing 10 g of diatomaceous earth powder with a dry mixer, 35 m/m of silica sol having a concentration of 30% by weight was added. After thoroughly kneading this mixture, it was dried and solidified at 120°C. The particles were then pulverized to a particle size of 20 to 60 mesoyu to obtain a carrier (A).

Preparation Example 2 Coal-based activated carbon 15 crushed to a particle size of 200 mesh or less
g and 5 g of silica alumina powder were thoroughly mixed using a dry mixer, and then 35 mA of silica sol having a concentration of 20% by weight was added and further thoroughly kneaded. After drying this kneaded product at 120°C, the temperature was raised to 300°C and heat-treated for further 2 hours.

Next, the mixture was allowed to cool and then ground to obtain a carrier (B) with a uniform particle size of 20 to 60 granules.

Preparation Example 3 Coal-based activated carbon Lo crushed to a particle size of 200 mesh or less
After thoroughly mixing 10 g of cupric oxide (CuO) with 10 g of cupric oxide (CuO), a silica sol 3 Q m 7! was added and thoroughly kneaded. This kneaded product was dried at 120° C. and then pulverized to have a uniform particle size of 20 to 60 mesh to obtain a carrier (C).

Example 4: 10 g of coconut husk charcoal crushed to a particle size of 200 mesosius or less
10 g of magnesium pyrophosphate (2Mgo.P2O5) powder and 35 mj2 of No. 3 sodium silicate were added to the mixture, thoroughly kneaded, and then dried at 150°C. Then crush, 2
The particle size was adjusted to 0 to 60 mesh to obtain a carrier (D).

S Peripheral Example 5 30 m2 of silica sol having a concentration of 30% by weight was added to 10 g of coal charcoal and 10 g of kaolinite powder crushed to a particle size of 200 mesh or less, thoroughly kneaded, and then dried at 120°C. Then, heat treatment was further performed at 800° C. for 2 hours in a nitrogen stream. After being left to cool, it was pulverized to a particle size of 20 to 60 mesh to obtain a carrier (E).

II Preparation Example 6 10 g of coal charcoal crushed to a particle size of 200 mesosius or less,
Zirconium oxide (ZrO2) prepared to similar particle size5
After dry mixing 5 g of nickel oxide (Ni0) and 5 g of nickel oxide (Ni0), silica sol 3Qm6 with a concentration of 30% by weight was added, thoroughly kneaded, and dried at 120°C. Next, this was further heat-treated at 300°C for 2 hours, and then crushed to give a
The particle size was adjusted to 60 mesh to obtain a carrier (F).

(2) Preparation of carrier-supported catalyst The above-mentioned carriers (A) to (E) each prepared by the method (1)
), 2 m of palladium chloride aqueous solution with 0.1 mol/β concentration, 1 ml of cupric chloride aqueous solution with 1 mol/β concentration
mj! A mixed aqueous solution consisting of 1 ml of a copper nitrate aqueous solution having a concentration of 1 mol/β was added to the carrier to impregnate the catalyst component consisting of a palladium salt and a copper salt. 4 each
The carrier-supported catalyst (A)′(B) of the present invention was dried at 0°C.
', (C)', (D)' and (E)' were obtained.

Regarding carrier (F), 1 as copper salt per 3 g of carrier.
Mol/7! 1 each of aqueous solutions of cupric chloride and copper sulfate
．． Catalyst (F)' was obtained in the same manner as in the case of supports (A) to (E) except that 5 ml was used.

(3) 20 Qmg of each of the carrier-supported catalysts of the present invention obtained in the test for removing CO in tobacco smoke (2),
A portion of the filter of a product cigarette (product name highlight) was filled with it. Connect this cigarette to an automatic smoking device,
Smoking was performed for 6 puffs under standard smoking conditions (35m7! inhalation/1 puff, 2 seconds/1 puff), and the C○ concentration in the obtained mainstream smoke gas was measured using a non-dispersive infrared spectrophotometer needle (ND-IR). It was measured using In addition, using γ-alumina and coconut husk charcoal as carriers, the CO concentration was measured in the same way as a comparison sample with a catalyst on which catalyst components were supported in the same way as in the case of the carriers A-E, and the same amount of only coconut husk charcoal was used as a comparison sample. The CO concentration was similarly measured using the filter filled as a control. From the above measured values, the CO removal rate relative to the control was calculated and the results are shown in Table 1.

Table 1 Note that the CO removal rate was calculated using the following formula.

As is clear from the results in Table 1, the filter filled with the carrier-supported catalyst of the present invention exhibited a CO removal rate 2 to 2.7 times higher than that of the catalyst using coconut husk charcoal alone as a carrier, and the γ-
It had performance comparable to that of an alumina carrier.

(4) Cigarette Smoke Flavor and Flavor Test Samples obtained in the same manner as in (3) were evaluated by a trained professional sensory panel of 10 people, and the results are shown in Table 2.

Table 2 As seen in the evaluations in Table 2, the carrier-supported catalyst of the present invention has almost no adverse effect on the aroma and flavor of tobacco smoke, and all panelists agreed that there was no difference between the control product and the coconut husk charcoal filter. On the other hand, the γ-alumina carrier catalyst was found to have a significant negative impact on the aroma and taste of tobacco.

(Effects of the Invention) As described in detail above, including the Examples, the present invention comprises a mixed composition of a metal oxide and activated carbon as a carrier, and a mixture of a palladium salt and a copper salt supported on the carrier. This CO removal catalyst can significantly reduce CO in smoke without reducing the aroma and taste of tobacco smoke.

Patent applicant: TOBIA GYO Co., Ltd.
Japan Monopoly Corporation

Claims (3)

[Claims] (1) An agent for removing carbon monoxide from tobacco smoke, characterized in that a mixture of a palladium salt and a copper salt is supported on a carrier made of a mixed composition of a metal oxide and activated carbon. (2) Metal oxides are MgO, Al_2O_3, SiO_
2. The carbon monoxide remover in tobacco smoke according to claim 1, which contains one or more selected from the group consisting of P_2O_5 and transition metal oxides. (3) The metal oxide contains MgO or Al_
The carbon monoxide remover in tobacco smoke according to claim 1, which is a silicate mineral containing one or more of 2O_3.