JP2014232074A - Phosphoric acid measurement kit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a phosphoric acid measurement kit that enables a phosphoric acid ion in a specimen to be easily measured.SOLUTION: A phosphoric acid measurement kit 1 comprises: a bottomed optical cell that has a first opening at one end, and makes at least a part of a peripheral wall light transmissive, and makes light incident from the peripheral wall emittable from a facing peripheral wall; and a lid member 32 that is capable of blocking the first opening of the optical cell. The lid member 32 includes a bottomed cylindrical accommodation part 321 that is capable of being fluid-tightly fitted into an inner side of the first opening, and that has a second opening 321a at one end. An acidic solution containing a molybdate ion is accommodated in an optical cell main body 2, and an ascorbic acid is accommodated in the accommodation part 321 in a state where the ascorbic acid is isolated from the acidic solution containing the molybdate ion.

Description

  The present invention relates to a phosphoric acid measurement kit.

  Phosphorus is known as a causative substance of eutrophication in rivers and oceans, and there are emission regulations for wastewater discharged into the natural environment. Therefore, the quantification of phosphorus in wastewater, particularly the quantification of phosphate ions, is routinely performed.

  The method for quantifying phosphate ions contained in water is defined as molybdenum blue absorptiometry in JIS K0102 “Factory Wastewater Test Method” (2010) 46.1.1. Based on this measurement principle, various measurement methods have been proposed (see, for example, Patent Documents 1 and 2).

JP 2005-99014 A JP 2011-227040 A

  In the JIS standard method, the molybdate complex of phosphate ions is reduced using ascorbic acid. However, ascorbic acid is oxidatively deteriorated and colored when stored for a long time in the form of an aqueous solution, so it is necessary to control the storage temperature and storage period. Further, when preparing an aqueous solution by dissolving solid ascorbic acid immediately before the measurement, the operation becomes complicated. For this reason, there has been a demand for a technique that allows simple measurement of phosphate ions dissolved in wastewater or the like as a sample.

  This invention is made | formed in view of such a situation, Comprising: It aims at providing the kit for a phosphoric acid measurement which can measure the phosphate ion in a sample simply.

  In order to solve the above problems, one embodiment of the present invention has a first opening at one end, at least a part of the peripheral wall is light-transmitting, and light incident from the peripheral wall can be emitted from the opposing peripheral wall. A bottomed optical cell, and a lid member capable of closing the first opening of the optical cell, the lid member being capable of being liquid-tightly fitted inside the first opening, and A bottomed cylindrical storage portion having a second opening at one end, an acidic solution containing molybdate ions in the optical cell, and an acidic solution containing molybdate ions in the storage portion; Provides a kit for measuring phosphate containing ascorbic acid in an isolated state.

  According to an aspect of the present invention, the connection between the inside of the optical cell and the outside of the optical cell through the first opening, or the inside of the housing and the housing through the second opening. It is good also as a structure which has the isolation | separation member which isolate | separates the acidic solution containing the said molybdate ion and the said ascorbic acid by interrupting | blocking at least any one of the connection with the exterior of this.

  According to an aspect of the present invention, the separating member is detachably attached to the optical cell and the lid member in a state where the lid member does not block the first opening, The first opening and the second opening may be sealed together in a state where the portion is not fitted inside the first opening.

  According to an aspect of the present invention, the optical cell has an opening at one end, at least a part of the peripheral wall is light-transmitting, and light incident from the peripheral wall can be emitted from the opposing peripheral wall. A first member on the bottom and a second member provided at one end of the first member and having a through-hole penetrating through the first member, and the opening and the through-hole communicate with each other to form the first opening The isolation member may be sandwiched and fixed between the first member and the second member.

  ADVANTAGE OF THE INVENTION According to this invention, the kit for a phosphoric acid measurement which can measure the phosphate ion in a sample simply can be provided.

It is a perspective view which shows the kit for a phosphoric acid measurement of this embodiment. It is sectional drawing of the kit for a phosphoric acid measurement of this embodiment. It is explanatory drawing which shows the phosphoric acid measuring method using the kit for phosphoric acid measurement of this embodiment. It is the elements on larger scale which show the state which closed the 1st opening part with the cover material. It is sectional drawing of the modification of the kit for phosphoric acid measurement.

  Hereinafter, the phosphoric acid measurement kit according to the embodiment of the present invention will be described with reference to the drawings. In all the drawings below, the dimensions and ratios of the constituent elements are appropriately changed in order to make the drawings easy to see.

(Phosphate measurement kit)
FIG. 1 is a perspective view showing a phosphoric acid measurement kit 1, in which FIG. 1 (a) shows a state during storage, and FIG.

  The phosphoric acid measurement kit 1 of the present embodiment includes an optical cell main body (first member) 2, a lid unit 3, and a sealing material (separating member) 4. The optical cell body 2 accommodates a first reagent 5 described later.

  As shown in FIG. 1B, the lid unit 3 connects the base material (second member) 31 provided at one end of the optical cell body 2, the lid material 32, the base material 31, and the lid material 32. And a hinge 33. The base material 31 is provided with a through hole 311a connected to the inside of the optical cell main body 2, and the lid member 32 is provided with a storage portion 321 for storing a second reagent described later.

  As shown in FIG. 1A, in the phosphoric acid measurement kit 1, the sealing material 4 covers the base material 31 and the lid material 32 in the storage state. Moreover, as shown in FIG.1 (b), by peeling off the sealing material 4 at the time of use, the 2nd opening part 321a of the accommodating part 321 which the through-hole 311a of the base material 31 has, and the cover material 32, Is configured to be exposed.

  FIG. 2 is a cross-sectional view of the phosphoric acid measurement kit 1.

  The optical cell body 2 is a bottomed cylindrical prism having an opening 2a at one end. The peripheral wall is light-transmitting so that measurement by an absorptiometry is possible, and light incident from the peripheral wall faces each other. It is comprised so that it can radiate | emit from a surrounding wall. As the optical cell body 2, for example, a square cell having an optical path length of 10 mm can be adopted. The optical cell body 2 can be made of glass or quartz as a forming material, but it is made of an acrylic resin such as polymethyl methacrylate (PMMA), a polyester resin such as polyethylene terephthalate (PET), or a resin material such as polystyrene. It is good. An external thread 2b is formed on the outer side of the optical cell body 2 where the opening 2a is provided.

  An internal thread 31 a is formed on the base material 31, and is fixed to the external thread 2 b of the optical cell body 2. Further, the through hole 311 a of the base material 31 communicates with the opening 2 a of the optical cell body 2. In the present embodiment, the combined structure of the optical cell main body 2 and the base material 31 corresponds to the “optical cell” in the present invention, and the opening formed by communicating the opening 2a and the through hole 311a, This corresponds to the “first opening” in the present invention.

The lid member 32 has a bowl shape having a bottom portion 32a and a closed annular side wall 32b provided on the periphery of the bottom portion 32a. It has a bottomed cylindrical housing 321 configured. As will be described later, the accommodating portion 321 has a size capable of being liquid-tightly fitted into the through hole 311a.
The base material 31 and the lid member 32 are connected by a hinge 33.

  The lid unit 3 (base material 31, lid material 32 and hinge 33) is integrally formed of a resin material. The lid unit 3 may be formed using the same material as the optical cell body 2 such as an acrylic resin, a polyester resin, or polystyrene, or may be formed using a different material. The lid unit 3 preferably has a light shielding property.

  The sealing material 4 is made of a metal material such as aluminum, for example, and a resin film may be formed on the surface as necessary. The sealing material 4 is, for example, a sheet-like or film-like member, and the end portion (first opening) and the second portion of the through hole 311a in a state where the accommodating portion 321 is not fitted inside the through hole 311a. It is attached so as to seal the opening 321a together and is provided so as to be peelable. The sealing material 4 blocks the connection between the inside and the outside of the optical cell main body 2 through the through hole 311a, and the connection between the inside and the outside of the housing portion 321 through the second opening 321a. In the previous period, the first reagent 5 and the second reagent 6 are isolated. In addition, the sealing material 4 prevents the first reagent 5 and the second reagent 6 from coming into contact with the outside air during the period from storage to before use. The first reagent 5 and the second reagent 6 Is preventing deterioration.

  The first reagent 5 is an acidic solution containing molybdate ions. The “acidic solution containing molybdate ions” of the present invention can be used if it contains molybdate ions and the pH of the solution is acidic. When preparing an acidic solution containing molybdate ions, molybdate can be used as a source of molybdate ions. For example, sulfuric acid can be used as the acid for adjusting the acidity of the solution. Moreover, in order to make it color strongly in the coloring reaction mentioned later, it is good to contain antimonyl potassium tartrate.

  Examples of such an “acidic solution containing molybdate ions” include a mixed aqueous solution of molybdic acid, sulfuric acid, and potassium antimonyl tartrate. Further, as the acidic solution containing molybdate ions, an ammonium molybdate solution defined in JIS K0102 “Factory Wastewater Test Method” (2010) 46.1.1 can also be used. A known amount of the first reagent 5 is accommodated in the optical cell body 2.

  The second reagent 6 is solid ascorbic acid. As the form of ascorbic acid, various forms such as powder, fine granules, and granules can be adopted. However, ascorbic acid needs to be dissolved in the operation described later, the smaller the particle size is preferable. An excessive amount of the second reagent 6 is accommodated in the accommodating portion 321 with respect to a necessary amount in a reduction reaction described later.

(Phosphoric acid measurement method)
FIG. 3 is an explanatory diagram showing a phosphoric acid measurement method using the phosphoric acid measurement kit 1 of the present embodiment.

  First, as shown in FIG. 3A, the sealing material 4 is peeled from the phosphoric acid measurement kit 1 to expose the through hole 311a and the second opening 321a. Thereafter, a sample 7 such as waste water to be measured is injected into the optical cell body 2 through the through hole 311a. The amount of the sample 7 to be injected is specified in advance, and the specified amount is injected using a pipette or the like. Thereby, the 1st reagent 5 and the sample 7 are mixed. In the mixed solution of the first reagent 5 and the sample 7, the molybdate ion in the first reagent 5 and the phosphate ion in the sample 7 form a complex.

  Next, as shown in FIG. 3B, the hinge 33 is bent, and the accommodating portion 321 of the lid member 32 is fitted into the through hole 311a. Thereby, the lid member 32 closes the through hole 311a (first opening) in a state where the inside of the accommodating portion 321 faces the inside of the optical cell main body 2.

  Next, in a state where the through-hole 311 a is sealed with the lid member 32, the entire optical cell body 2 and the lid unit 3 are shaken and mixed, so that the mixed solution 8 of the first reagent 5 and the sample 7 is placed inside the storage portion 321. In contact with the second reagent 6 contained therein, the second reagent 6 is dissolved, and left for 5 minutes, for example. In the mixed solution 8 in which the second reagent 6 is dissolved, the molybdate complex is reduced by ascorbic acid and colored blue. This blue intensity is proportional to the phosphate ion concentration in the sample 7.

  Here, FIG. 4 is a partially enlarged view showing a state in which the through hole 311a is closed by the lid member. FIG. 4A shows a case where the through-hole 311 a is closed using the lid member 132 when the phosphoric acid measurement kit 100 including the lid member 132 not having the accommodating portion 321 is assumed. FIG. 4B shows a case where the through hole 311a is closed by the lid member 32 of the present embodiment.

  First, as illustrated in FIG. 4A, when the phosphate measuring kit 100 including the lid member 132 that does not have the accommodating portion 321 is assumed, the second reagent 6 is accommodated in the lid member 132. It is possible to dissolve the second reagent 6 in the mixed liquid in the optical cell body 2 by closing the lid member 132 and shaking and mixing. However, in the lid member 132 having such a configuration, the second reagent 6 remaining undissolved in the space (shown by α in the drawing) between the through hole 311a and the side wall of the lid member 132 and the mixture to be measured are mixed. There is a possibility that the liquid may accumulate, which causes the measurement value to fluctuate.

  On the other hand, in the phosphoric acid measurement kit 1 of the present embodiment shown in FIG. 4 (b), the lid member 32 has a housing portion 321, and the housing portion 321 is liquid-tightly fitted into the through hole 311a. The through hole 311a is closed. Thereby, the second reagent 6 accommodated in the accommodating portion 321 faces the inside of the optical cell main body 2, and the second reagent 6 is obtained by shaking and mixing the entire optical cell main body 2 and the lid unit 3. Can be dissolved easily. Therefore, the liquid mixture to be measured can be reliably adjusted using the entire amount of the second reagent 6, and the measurement value is stabilized.

  Next, as shown in FIG. 3C, the mixed solution 9 of the first reagent 5, the second reagent 6, and the sample 7 is measured by absorptiometry. The measurement can be performed using a generally known absorptiometer, and is performed using light having a wavelength of 490 nm to 700 nm. In addition, a blank test sample in which pure water is injected into the optical cell main body 2 is separately prepared, and the measurement is performed in the same manner to obtain a correction value. In this way, a correction value of the extinction coefficient measured for the blank test sample is subtracted from the extinction coefficient measured for the mixed liquid 9 to obtain a true extinction coefficient for the mixed liquid 9.

  By preparing a calibration curve indicating the relationship of the absorption coefficient with respect to the phosphate ion concentration in advance, the phosphate ion in the sample 7 is obtained from the true absorption coefficient for the mixed liquid 9 obtained with reference to the calibration curve. The concentration can be determined.

  According to the phosphoric acid measurement kit 1 configured as described above, since solid ascorbic acid is sealed in the housing portion 321 during storage, oxidative degradation can be prevented. Moreover, the lid 32 connected by the hinge 33 is closed, and the solid ascorbic acid is dissolved to adjust the measurement liquid mixture by a simple operation of shaking the entire optical cell body 2 and the lid unit 3 together. can do. Therefore, according to the kit 1 for measuring phosphoric acid, phosphate ions in the sample can be easily measured.

  The preferred embodiments of the present invention have been described above with reference to the accompanying drawings, but it goes without saying that the present invention is not limited to such examples. Various shapes, combinations, and the like of the constituent members shown in the above-described examples are examples, and various modifications can be made based on design requirements and the like without departing from the gist of the present invention.

  For example, in the present embodiment, the base material 31 and the lid material 32 constituting the lid unit 3 are connected by the hinge 33, but there is no hinge 33 and the base material 31 and the lid material 32 are independent. A configuration can also be adopted.

  In the present embodiment, the optical cell main body 2 and the base material 31 are configured as separate bodies, and are described as being configured to be screwed using the male screw 2b and the female screw 31a respectively formed. The optical cell body 2 and the base material 31 may be integrally formed of a transparent resin.

  In the present embodiment, the peripheral wall of the optical cell main body 2 is light transmissive. However, the entire peripheral wall of the optical cell main body 2 is not necessarily required to be light transmissive. As long as a part of the opposed peripheral walls is light transmissive and light incident from the peripheral wall is configured to be emitted from the opposed peripheral walls, the other peripheral walls may be configured to have no light transmissive property. .

  In the present embodiment, the sealing material 4 is attached so as to seal the through hole 311a and the second opening 321a together, and is provided so as to be peelable. Not limited to.

FIG. 5 is an explanatory diagram according to a modification of the present embodiment, and corresponds to FIG.
In the phosphoric acid measurement kit 11 shown in FIG. 5A, the opening 2a is sealed at the end of the through-hole 311a on the optical cell body 2 side instead of the sealing material 4 described in the above embodiment. It has a first sealing material (separating member) 41 and a second sealing material (separating member) 42 that seals the end of the second opening 321a (the end of the accommodating portion 321). The first sealing material 41 is sandwiched and fixed between the optical cell main body 2 and the base material 31. In such a phosphoric acid measurement kit 11, the through hole 311 a and the second opening 321 a are individually sealed by the first sealing material 41 and the second sealing material 42.

  When the phosphoric acid measurement kit 11 is used, a hole is made in the first sealing material 41, and a sample 7 (see FIG. 3) such as drainage is put into the optical cell body 2 through the formed hole. On the other hand, after the second sealing material 42 is peeled off, the lid 32 is closed and the phosphoric acid measurement kit 11 is shaken and mixed to adjust the blue colored mixture, and the resulting mixed solution absorbs light. Measure the coefficient.

  In the phosphoric acid measurement kit 11 having such a configuration, the lid member 32 is closed and penetrated in a state where the first reagent and the second reagent are isolated by the first sealing material 41 and the second sealing material 42. The hole 311a can be closed and stored. Therefore, it is possible to suppress breakage due to interference between the lid members 32 during storage and transfer, and it is possible to efficiently store many phosphoric acid measurement kits 11 even in a narrow storage place.

  In the phosphoric acid measurement kit 11, the connection between the inside and the outside of the optical cell main body 2 via the first opening, or the connection between the inside and the outside of the accommodating portion 321 via the second opening 321a, As long as at least one of them can be blocked, for example, the second sealing material 42 may not be provided. In that case, in order to suppress the deterioration of the second reagent 6 during storage, the lid 32 is closed during storage of the phosphoric acid measurement kit 11 to prevent contact between the second reagent 6 and air. Good.

  Further, as in the phosphoric acid measurement kit 12 shown in FIG. 5B, the first cap (isolation member) 43 that seals one end of the through hole 311a and the end of the second opening 321a are sealed. The second cap (isolation member) 44 may be included. As the first cap 43 and the second cap 44, for example, rubber ones can be used.

  DESCRIPTION OF SYMBOLS 1 ... Phosphate measuring kit, 2 ... Optical cell main body, 2a ... Opening part, 3 ... Cover unit, 4 ... Sealing material, 32 ... Cover material, 33 ... Hinge, 311a ... Through-hole, 321 ... Storage part, 321a ... Second opening

Claims (4)

A bottomed optical cell having a first opening at one end, at least a part of the peripheral wall being light transmissive, and allowing light incident from the peripheral wall to be emitted from the opposing peripheral wall;
A lid capable of closing the first opening of the optical cell,
The lid member includes a bottomed cylindrical accommodating portion that can be liquid-tightly fitted inside the first opening and has a second opening at one end;
An acidic solution containing molybdate ions is contained in the optical cell;
A kit for measuring phosphoric acid in which ascorbic acid is housed in the housing part in a state isolated from the acidic solution containing the molybdate ions.   At least one of the connection between the inside of the optical cell and the outside of the optical cell through the first opening, or the connection between the inside of the housing and the outside of the housing through the second opening. The kit for measuring phosphoric acid according to claim 1, further comprising a separating member that isolates the ascorbic acid from the acidic solution containing the molybdate ion by blocking either of them. The isolation member is detachably attached to the optical cell and the lid member in a state where the lid member does not block the first opening.
3. The kit for measuring phosphoric acid according to claim 2, wherein the first opening and the second opening are sealed together in a state where the housing is not fitted inside the first opening. The optical cell has an opening at one end, at least a part of the peripheral wall is light-transmitting, and a bottomed first member that allows light incident from the peripheral wall to be emitted from the opposing peripheral wall;
A second member provided at one end of the first member and having a through-hole penetrating through the first member;
The opening and the through hole communicate with each other to form the first opening;
The phosphoric acid measurement kit according to claim 2, wherein the isolation member is sandwiched and fixed between the first member and the second member.

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