JPH052336B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a deodorizing agent, more specifically a deodorizer for homes, factories,
This invention relates to a solid deodorizing agent for deodorizing bad odors generated from agricultural products, automobiles, etc. (Prior Art) Conventionally, solid deodorizing agents include those that adsorb and remove odors through physical adsorption (e.g., activated carbon, zeolite, alumina, etc.), and odorless compounds that chemically remove odor components. (For example, a carrier such as zeolite or alumina is impregnated with a solution deodorizer such as an iron compound or glyoxal). These solid deodorizers are in the form of powder, granules, or irregular shapes, and they can be placed in some kind of well-ventilated container and placed indoors, in a refrigerator, in a car, or filled into a factory exhaust gas treatment tower. It is used as such.
In addition, the shape of the container is mostly cylindrical, prismatic, etc. (Problems to be Solved by the Invention) However, these solid deodorizing agents have the following problems, and their solution has been strongly desired. That is, firstly, conventional solid deodorizing agents have a slow deodorizing speed and lack quick effectiveness. Second, the deodorizing effect did not last long, and the entire container or contents had to be replaced after about a month. Thirdly,
It is difficult to mold the deodorizer into arbitrary particles or molded objects, or even if molded, the strength is weak and it may lose its shape with weak force or turn into powder, which can conversely pollute the environment. It was hot. Fourth, the end point of the deodorizing effect was unclear, making it difficult to determine when to replace it. Fifth, when used in a packed tower or the like, there were problems such as a large pressure loss due to the particle shape and an increase in the size of the blower. (Means for Solving the Problems) The present inventors have conducted intensive studies to improve the conventional solid deodorizers, which have many problems as described above, and have previously proposed the following (Patent Application No. 1983). -10535) Porous particles of cellulose acetate are impregnated with an aqueous solution of a composition containing an iron compound as a main component (Japanese Patent Application Laid-open No. 156539/1983), which has a long-lasting deodorizing effect and is stable even during storage, and then dried. discovered that it could be a solid deodorizer with deodorizing power, sustainability, and ease of handling, and completed the present invention. That is, the present invention provides a solid deodorizing agent characterized in that porous particles of cellulose acetate support a composition containing an iron (2) compound as a main component. The cellulose acetate used in the present invention is so-called cellulose diacetate, which has a hydroxyl group and an acetyl group and has an acetylation degree of 50 to 58%. If the degree of acetylation is less than 50%, the particle strength is weak and it is easy to absorb moisture.
% is not preferable because it lacks hydrophilicity and when immersed in an aqueous solution of a composition containing an iron() compound as a main component, liquid penetration is slow and the amount of impregnation is small. In addition, the porous cellulose acetate used in the present invention can be obtained by extruding an acetone or acetic acid solution of cellulose acetate into a suitable coagulation bath, for example, an acetone aqueous solution or an acetic acid aqueous solution, forming it into an arbitrary shape while coagulating it, and washing it. Obtained by drying. The shape of this molded product can be various, but a granular shape, particularly a spherical shape, is advantageous in terms of increasing the surface area, toughness, and ease of handling during use. The particles produced by this method are characterized by a high degree of crushing despite the large pore volume within the particles. The cellulose acetate used in the present invention is a porous molded product having a pore volume of 0.7 cc/g or more and a crushing strength of 10 kg or more. If the pore volume is less than 0.7 cc/g, the amount of impregnation with an aqueous solution of a composition containing an iron () compound as a main component is small, and as a result, only a solid deodorizer with low deodorizing power can be obtained; In terms of pore volume, it is better to have more pores with small pore diameters, and preferably one with an average pore diameter of 1000 Å or less. The crushing strength is important because it prevents particles from contacting or colliding with each other and becoming powder during manufacturing processes such as the impregnation process with an aqueous solution of a composition mainly composed of iron () compounds, the drying process, and during use. The weight is preferably 10 kg or more, and the solid deodorizer of the present invention satisfies that requirement. Further, the size of the particles varies depending on the place where the deodorizing agent is used, but from the viewpoint of yield in the manufacturing process and ease of handling, a diameter of 3 to 5 mm is preferable. However, it is also possible to use particles formed by forming these particles into an arbitrary shape. A composition containing an iron () compound as a main component used in the present invention, a combination of an iron () compound and ascorbic acid and/or citric acid,
This can be made into an aqueous solution and impregnated into cellulose acetate. Examples of iron () compounds used in the composition containing iron () compounds as a main component of the present invention include ferrous sulfate, ferrous chloride, ferrous nitrate, ferrous bromide,
In addition to iron () inorganic salts such as ferrous iodide, iron () organic salts such as ferrous gallate, ferrous malate, and ferrous fumarate can be mentioned. The iron () compound is not limited to those exemplified above, and any compound can be used as long as it dissolves in water and forms divalent iron ions. Ascorbic acid, L-ascorbic acid, D-isoascorbic acid (erythorbic acid)
is used, but L-ascorbic acid is preferred. In the present invention, ascorbic acid and citric acid may be used alone or in combination. When used together, citric acid is thought to act as a stabilizing agent for ascorbic acid. Further, the ratio of the iron () compound to ascorbic acid and/or citric acid in the composition containing the iron () compound as a main component is preferably in the range of 1:0.02 to 0.3 (weight ratio), more preferably 1:0.03. ~0.1 range. Ascorbic acid and/or
Alternatively, if citric acid is used, the composition becomes colored and becomes uneconomical, and its freshness-keeping and deodorizing functions are reduced, and below the lower limit, the stability of iron () becomes insufficient. In the present invention, it is preferable that the iron() compound and ascorbic acid and/or citric acid are combined, and this can be easily done by forming a composition containing the iron() compound as a main component into an aqueous solution. can. Further, for impregnating the carrier with this aqueous solution, a known method such as a method of impregnating the carrier into the above-mentioned aqueous solution or a method of sprinkling the aqueous solution onto the carrier can be used. The subsequent drying is carried out using a known drying method without any problems, and through this drying, only the deodorant is trapped in the pores of the particles, making it possible to obtain an excellent solid deodorizer extremely easily. . Further, the solid deodorizing agent of the present invention can achieve its purpose by placing it in a container and placing it indoors, in a car, etc. Furthermore, when used as a deodorizing agent for malodorous gases in factories, etc., it can be used by filling exhaust ducts. In that case, the pressure loss due to the packed bed can be reduced by making the product of the present invention spherical. Furthermore, by coating the surface of the product of the present invention with a special water-insoluble film, it can also be used as a water deodorizer. (Effects of the Invention) Comparing the products of the present invention with conventional products, the following table shows that the products of the present invention are superior.

[Table] (Note) ◎ Excellent △ Fair × Poor (Examples) The present invention will be explained in more detail with reference to Examples below. In addition, the physical property values of cellulose acetate in Examples were measured by the following method. (a) Degree of acetylation After drying approximately 5 g of the pulverized sample in a dryer at 100 to 105°C for 2 hours, weigh it accurately. Add 50 ml of purified acetone to this sample and after complete dissolution, add 50 ml of 0.2N-NaOH aqueous solution, then 50 ml of 0.2N-HCl aqueous solution in order, and use phthaenolphrein as an indicator.
Titrated with 0.2N-NaOH aqueous solution and calculated using the following formula: Degree of acetylation = (A-B) x F x 1.201/sample weight (
g) However, A: Titration number of 0.2N-NaOH aqueous solution (ml) B: Titration number of 0.2N-NaOH aqueous solution in blank test (ml) F: Factor of 0.2N-NaOH aqueous solution The degree of acetylation calculated by this method is acetic acid Content (%)
It is. (b) Pore volume The volume of mercury injected into the pores at a pressure of 0 to 1000 [Kg/cm ² G] using a mercury injection porosimeter (manufactured by Carlo Elpa) corresponds to the volume of pores of 75 to 75000 Å. It is expressed in volume per 1 g of sample. (c) Crushing strength Using a Monsanto tablet hardness tester (manufactured by Oiwa Pharmaceutical Machinery Co., Ltd.), calculate the average value of the measured values of 10 particles. In addition, parts and percentages indicating compositions in the examples indicate parts by weight and percentages by weight, respectively, unless otherwise specified. Example 1 10 g of spherical cellulose acetate with a degree of acetylation of 54.5%, pore volume of 0.95 cc/g, average pore radius of 900 Å, crushing strength of 15 kg, and average particle diameter of 4.6 mm was mixed with 1 part of ferrous sulfate and L
- 25 of a deodorizing composition consisting of 0.05 parts of ascorbic acid
% aqueous solution for 8 hours while stirring at room temperature. After that, the solid and liquid are separated using a wire mesh, and the solid content is reduced to 105
It was dried for 2 hours in a steam dryer at ℃ to obtain a spherical solid deodorizer. This product contained about 14% of the deodorizing composition and had the same apparent shape and size as the first one. Moreover, the crushing strength did not change, and the color was pale green. Furthermore, the destruction of particles during impregnation,
There was also no powdering. I put 1 g of this solid deodorizer in its original form into a glass container with a volume of 1 and ammonia gas concentration of 540 ppm.I shook the container well and measured the ammonia gas concentration after 30 minutes.It was 1.5 ppm, and I could not feel any ammonia odor. Ta. Comparative Example 1 When activated carbon (Kuraray Coal 4GG, manufactured by Kuraray Chemical Co., Ltd.), which is a commercially available solid deodorizer, was used instead of the solid deodorizer of Example 1, the ammonia gas concentration after 30 minutes was 300 ppm, and there was a strong ammonia odor. . When the time was further extended and the concentration was measured after 2 hours, 200 ppm of ammonia remained. Example 2 Spherical cellulose acetate with an acetylation degree of 54.9%, a pore volume of 0.9 cc/g, an average pore radius of 500 Å, a crushing strength of 20 Kg, and an average particle diameter of 3.5 mm was made into spherical cellulose acetate with a length of 50 cm, a width of 50 cm, and a height of 3 cm.
Filled into a rectangular wire mesh mold, immersed in ethyl acetate solution for 30 seconds, immediately removed from the solution, air-dried for 10 minutes, completely evaporated the solvent in a dryer at 105℃, removed from the dryer, and placed in a metal frame. was removed to obtain a rectangular parallelepiped molding. This product was immersed in the same deodorizing composition aqueous solution as in Example 1 for 8 hours so that the entire product was immersed in the liquid, and then dried to obtain a solid deodorizer. When this was used as a filter for the exhaust duct of a factory with a strong ammonia odor, the ammonia concentration of exhaust gas of 10,000 ppm was reduced to 2 to 3 ppm after passing through the filter. Comparative Example 2 When the activated carbon of Comparative Example 1 was used as a binder with carboxymethyl cellulose to make a molded article similar to that of Example 2 and used as a filter similar to that of Example 2, the ammonia concentration of the exhaust gas after passing through the filter was 1000 ppm. Furthermore, the molded product was extremely brittle and broke when tapped lightly.

Claims (1)

[Scope of Claims] 1. A solid deodorizer characterized in that porous particles of cellulose acetate support a composition containing an iron compound as a main component. 2 Porous particles of cellulose acetate have an acetylation degree of 50 to 58
%, a pore volume of 0.7 cc/g or more, and a crushing strength of 10 Kg or more. 3. The solid deodorizer according to claim 1, wherein the composition containing an iron () compound as a main component is a combination of the iron () compound and ascorbic acid and/or citric acid.