JPS60225688A - Filter for filtering purified water - Google Patents

Abstract

PURPOSE:To positively adsorb a mutagenic substance in urban tap water, by packing a container such as a column with chitin in a solid state to bring chitin to a water flowable state. CONSTITUTION:Chitin is formed into a molded body having a fibrous, film like or nonwoven fabric like shape in a powdery state or after dissolved in a solvent. A column is packed with this molded body to be used as a filter for filtering purified water.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a filter for filtering purified water, and particularly to a filter for removing mutagenic substances contained in purified water such as city tap water.

Purified water, especially chlorinated municipal tap water, contains mutagenic or carcinogenic substances.
It has been reported at academic conferences, etc.

Its removal is desired. For example, this is also stated in the ``mutagenicity level of urban tap water'' (Fujo et al.) in Doshi Daigaku Faculty of Science and Engineering Research Report, Volume 24, No. 3, page 61; CtlC13+ contained in water
CllBrC12+ CHBr+CI, CIIBr
a t CCl41CHx CI C11ll CL
It describes trihalomethane-based substances such as CHCl=CHCl, N11z C1,O-dichlorobenzene, and p-dichlorobenzene, and all of these substances contain Am.
It has been reported that es Te5t has mutagenicity or carcinogenicity, and the reduction or removal of these harmful substances, mainly trihalomethanes, contained in municipal tap water is currently a major issue.

Traditionally, shad has been included in municipal water supplies.

The use of activated carbon has been proposed as a method of removing odors, and is actually used in the form of cartridges in municipal tap water faucets. However, these do not actively remove mutagenic or carcinogenic substances such as trihalomethanes.

As a result of intensive research into filters that remove mutagenic substances from urban tap water, the present inventors discovered that mutagenic substances could be removed by using chitin as a filtering material, and thus arrived at the present invention. be.

That is, the present invention is a filter that contains chitin in the filter and is applicable to purified water sources such as city tap water.

Chitin as used in the present invention refers to poly(N-acetyl-D-glucosamine) or its derivatives obtained by treating crustaceans, insects, etc. with hydrochloric acid and hydrochloric acid to separate and purify protein and calcium components. means. As a derivative of chitin, for example, part or all of the acetylamino groups of chitin are deacetylated. The filter for purifying water sources of the present invention includes chemically modified chitin such as so-called chitosan, chitin etherified products, esterified products, carboxymethylated products, hydroxyethylated products, and 0-ethylated products. It is made into a container that can be filled with water.

To make the filter of the present invention9 For example, use chitin powder as it is or dissolve chitin in a solvent to form a fibrous
After forming a film, a non-woven ring, or various molded products, they may be packed in a column or the like. In the case of chitin in the narrow sense, which has many acetylgelcosacin groups, the specific method for producing the molded article is to use a mixed solution of trichloroacetic acid and a halogenated hydrocarbon, or a mixed solution of lithium chloride and N-methylpyrrolidone or dimethyl chloride. One method is to dissolve chitin in a mixed solution with acetamide to make a dope, and then coagulate this dope with water, alcohol, ketones, etc. In the case of chitin, so-called chitosan, which has many glucosamine groups, chitosan is dissolved in an acetic acid aqueous solution. Examples include a method of dissolving to make a dope and coagulating this dope in water or an alcohol solution containing an alkali.

The filter of the present invention can be attached to a city tap water faucet or the like and used to filter water, and can adsorb mutagenic substances when the water passes through the water.

Hereinafter, the present invention will be explained in more detail with reference to Examples.

Example 1. Comparative Examples 1 and 2 Chitin powder was treated with a 40% aqueous sodium hydroxide solution at 95° C. for 3 hours to produce chitosan powder.

This powdered chitosan was sufficiently washed with water and dried, and then dissolved in a 0.1 M acetic acid aqueous solution to give a concentration of 8% by weight.
chitosan dope was created. This dope is transported by a gear pump, extruded from a nozzle into methanol containing 5% by weight of sodium hydroxide, wet-spun, and has a single yarn denier of 2.
A multifilament of d was obtained. After thoroughly washing and drying this filament, cut it into a length of 30 mm.
It was made into cotton using an A-fiber opening machine. 5g of this cotton with an inner diameter of 2'cm
After filling a cylindrical column with a height of 5'r and m with city tap water chlorinated with tertiary sodium hypochlorite and flowing it at a rate of about 2♂/hr for one week, the cotton was removed from the column. , thoroughly washed with distilled water, and dried.

For comparison, 5 g each of commercially available 1.8 denier rayon thread (Comparative Example 1) and activated carbon (GP60 manufactured by Catara Industries) (Comparative Example 2) were taken and packed in the same cylindrical column as in Example 1, and the experiment was carried out. City tap water was run under the same conditions as in Example 1.

After drying, the cotton, yarn or activated carbon was ground into silk powder, then dispersed in dimethyl sulfoxide and subjected to the Ames test. Salmo TA-100 was used as the bacterial strain, and the number of mutagenic colonies was determined.

The results were as shown in Table 1. As is clear from Table 1, Salmonella TA-9 dispersed in the cotton of Example 1
8. In both TA-100 strains, a large number of colonies with mutations occurred compared to the control, whereas in the case of Comparative Example 1.2, there was no significant difference from the control, and in the case of Example 1, there was no mutagenicity. It was determined that the substance was adsorbed.

6- Example 2 Chitin powder was ground into 100 mesoyu pieces and 1N-11c
I for 1 hour at 4°C, and further treated with 3% NaOI+
The chitin powder was heated at 90°C for 3 hours in a liquid solution to remove calcium and protein contained in the chitin powder, and then washed with water repeatedly and dried. The chitin thus obtained was dissolved at room temperature in a dimethylacetamide solution containing 7% by weight of lithium chloride to a concentration of 7% by weight. The obtained solution was filtered through 800 Mg steel, left to degas, then put into a tank, transported under pressure with a gear pump, and pushed out through a nozzle with 2 diameters of 0.07 mm and 200 holes into water, which is a coagulating liquid. It was solidified and wound up using a perforated pobbin at a speed of 10 m/min. When this bobbin was thoroughly washed with warm water and dried, the thread denier was 1.56.
chitin fibers were obtained.

Pack 5g of this chitin fiber into the same column as in Example 1,
Approximately 2n of chlorinated city tap water for one week? /h
After flowing with r, the fibers were taken out from the column, washed with methanol, and dried. The dried fibers were pulverized, dispersed in dimethyl sulfoxide, and subjected to the ^mes test in the same manner as in Example 1, and the results shown in Table 2 were obtained.

As is clear from Table 2, in the case of Example 2 as well, it was found that mutagenic substances in city tap water were adsorbed similarly to Example 1.

Patent applicant: Yu-Tei Riki Co., Ltd.

Claims (1)

[Claims] (1) A filter that can be applied to purified water sources such as urban tap water, which contains chitin in the filter.