CN111830026A

CN111830026A - Rapid detection method and kit for potassium ions

Info

Publication number: CN111830026A
Application number: CN202010708340.5A
Authority: CN
Inventors: 潘咏梅; 章德宏; 温杰
Original assignee: Guan Universal Biochemical Technology Co ltd
Current assignee: Guan Universal Biochemical Technology Co ltd
Priority date: 2020-07-21
Filing date: 2020-07-21
Publication date: 2020-10-27

Abstract

The invention relates to a rapid detection technology of potassium ions in a water body, in particular to a rapid detection method of potassium ions and a kit. The potassium ion rapid detection kit comprises: a precipitating agent comprising sodium tetraphenylborate or a solution thereof; the measuring rod comprises a measuring handle with scales and a measuring marker connected with one end of the measuring handle; or also a measuring vessel. The invention also provides a method for detecting potassium ions in water by using the test kit. The potassium ion rapid detection method and the kit provided by the invention can simply and rapidly detect potassium ions in water.

Description

Rapid detection method and kit for potassium ions

Technical Field

The invention relates to a rapid detection technology of potassium ions in a water body, in particular to a method and a kit for rapidly detecting potassium ions.

Background

Potassium ion (K) in water⁺) Is an important index of water, and particularly has extremely important significance for aquaculture. The action of potassium ions on aquatic animals and plants is multifaceted, the most important of which is ion transport enzyme (Na)⁺-K⁺-ATPase) plays an important regulatory role. The lack of potassium ions in the water body can seriously affect the growth and survival of aquatic animals. With the further development of research, the role of potassium ions in aquaculture is receiving more and more attention. Therefore, the determination and adjustment of the potassium ion concentration in the water body also become a necessary trend in the development of aquaculture. However, a key factor in the implementation process limits the popularization and application of the method, and the factor isDetection technology of potassium ions.

The potassium ion is measured by a very large number of methods, including a flame photometry, an atomic absorption spectrophotometry, an ICP method for measuring the potassium ion content, and a sodium tetraphenylborate gravimetric method. However, the method needs professional instruments, equipment and personnel for operation, consumes more time and higher cost, and is completely not suitable for aquaculture farmers to operate the pond. Therefore, the measurement and adjustment of potassium ions are more limited in a laboratory, and are not widely popularized and used in actual farmers, and the loss of aquatic animals caused by water ions is neglected, so that the loss of the farmers is caused; meanwhile, because potassium ions in the water body cannot be measured, the existing water body cannot be reused after being adjusted, the used water is directly discharged, and new aquaculture water is prepared again, so that the environmental pollution and the water resource waste are caused.

For potassium ions in the aquaculture water, the water quality difference of different regions is large, the demand quantity of cultured animals of different species and even different stages of the same species for the potassium ions is greatly changed, and the potassium ion concentration is dozens, hundreds or even thousands of times different from that of fresh water and seawater and desalinated seawater. The difference also brings challenges to the detection technology, increases the detection difficulty and requirements on detection personnel, further leads to the monitoring and adjustment of potassium ions, and is difficult to popularize in the practical application of aquaculture.

Among many methods, the sodium tetraphenylborate gravimetric method is the detection method with the lowest investment cost, and uses sodium tetraphenylborate and potassium tetraphenylborate to generate potassium tetraphenylborate precipitate, and after filtration, drying and weighing are carried out to calculate the content of potassium ions in the water body. However, the method requires a filter device and a drying device and an electronic balance, and a series of calculation is required to obtain the result, so that the method consumes several hours (more than 4 hours), and is obviously not suitable for farmers to operate and use. Besides, the potassium content can be calculated by using a spectrophotometric turbidimetry method by using sodium tetraphenylborate, forming potassium tetraphenylborate precipitate and measuring the transmittance of the obtained suspension by using a spectrophotometer in the same way as the principle.

The concentration range of potassium ions in different water bodies is wide, from a few ppm to thousands of ppm, and under the condition of uncertain concentration, the detection method usually needs a plurality of times of experiments to obtain results. For example, when the potassium ion concentration is high, the precipitation method or the turbidity method may cause that the added precipitant is insufficient or exceeds the linear detection range, and the experiment failure needs to be determined again.

Disclosure of Invention

The inventor in practice finds that sodium tetraphenylborate forms potassium tetraphenylborate precipitate with potassium ions, and the precipitate forms suspension with turbidity proportional to the concentration of potassium ions. I.e. the suspension of the same depth, the greater its concentration, the shorter the distance the light can be transmitted; the same object is seen through the suspension, and the distance of the object penetrating into the liquid surface is smaller as the concentration of the object is higher.

Based on the above findings, the embodiment of the invention provides a method and a kit for rapidly detecting potassium ions, which can simply and rapidly detect potassium ions in a water body.

Terms and definitions referred to in the present invention:

water sample to be detected: the invention needs the detected water sample.

Blank water sample: in the invention, if the water sample to be detected contains high potassium ion concentration, pure water which does not contain or contains a very small amount of potassium ions and is used for diluting the water sample is required.

Liquid to be detected: in the invention, the liquid (such as suspension) is obtained by adding the precipitant into the water sample to be detected or the diluted water sample to be detected.

A precipitant: the reagent required by the invention for measuring potassium ions comprises sodium tetraphenylborate or a solution thereof; in some cases also an acid-base modifier or a solution thereof; in some cases, the ion source also comprises a masking agent or a solution thereof for eliminating other ion interference; the acid-base regulator can adopt some common acids (such as phosphoric acid, sulfuric acid, disodium hydrogen phosphate, citric acid and the like), common bases (such as sodium hydroxide, sodium carbonate and the like); the masking agent may be selected from disodium EDTA, isopropanol, and the like.

The water sample measuring device comprises: measuring tools (such as a graduated pipette, a syringe, a measuring cylinder, a measuring cup and the like) for diluting a water sample containing high-concentration potassium ions.

Measuring container (sometimes also called measuring cup): the invention relates to a container for containing liquid to be detected; in some cases, the container is transparent, in the shape of a column (cube or cylinder); in some cases, the container has a depth; the container may have one or more graduations (e.g., 10mL, 20mL, 50mL, etc.).

Measuring a rod: the device for measuring the potassium ion concentration comprises a measuring handle with scales and a measuring marker connected with one end of the measuring handle; in some cases, the radial direction of the measurement marker is perpendicular or substantially perpendicular to the length direction of the measurement shaft. When in use, the upper end of the measuring handle is pinched, and one end of the measuring handle connected with the measuring marker is put into the liquid to be measured.

Measuring the marker: the device, which is arranged at one end of the measuring shaft of the measuring stick, observes its changes during the measurement until it reads the scale values on the measuring shaft when the liquid to be measured disappears (i.e. cannot be seen visually).

A potassium ion rapid detection kit comprises:

a precipitating agent comprising sodium tetraphenylborate or a solution thereof;

the measuring rod comprises a measuring handle with scales and a measuring marker connected with one end of the measuring handle;

or also a measuring vessel.

In some embodiments, the precipitating agent is sodium tetraphenylborate or a solution thereof.

In some embodiments, the precipitating agent comprises an acid-base modifier or a solution thereof in addition to sodium tetraphenylborate or a solution thereof. The main function of the pH regulator is to adjust a water sample to be in alkalescence, and ensure that potassium ions and sodium tetraphenylborate can generate stable precipitates. Wherein, the alkali in the acid-base regulator is commonly used, but when the alkalinity of the water body is too high, the acid can be used for adjusting back properly; the pH regulator can be selected from common acids (such as phosphoric acid, sulfuric acid, disodium hydrogen phosphate, citric acid, etc.), common bases (such as sodium hydroxide, sodium carbonate). It is understood that the pH modifying agent used in the present invention does not contain potassium ions.

In some embodiments, the precipitating agent includes, in addition to sodium tetraphenylboron or a solution thereof, a masking agent for eliminating interference of ions other than potassium ions or a solution thereof; the masking agent may be selected from disodium EDTA, isopropanol, and the like.

Herein, when the precipitant is sodium tetraphenylborate (which refers to a solid), sodium tetraphenylborate can be used directly as a solid. In some embodiments, the precipitating agent includes a solid diluent, such as sodium chloride, in addition to sodium tetraphenylborate. In practice, the solid diluent is added into the sodium tetraphenylborate, so that the accuracy of spoon sampling of the dosage can be improved, and the problem that the sampling quantity is inaccurate due to the light density of the sodium tetraphenylborate, the result accuracy is influenced or unnecessary waste is caused is solved. Herein, when the precipitant is sodium tetraphenylborate (referring to solids), the sodium tetraphenylborate solids can be used directly; meanwhile, a mixture of the sodium tetraphenylborate and the sodium chloride after grinding can be used for conveniently measuring the sodium tetraphenylborate (the sodium tetraphenylborate is loose, and the common measuring spoon is difficult to measure and quantify); wherein, the proportion of the sodium tetraphenylborate in the mixture is preferably 1 wt% -70 wt%. In some embodiments, the kit may be equipped with a dosing spoon to facilitate dosing of the precipitating agent as sodium tetraphenylborate.

Herein, a precipitant other than sodium tetraphenylboron or a solution thereof is sometimes referred to as a precipitation modifier.

Herein, when the precipitant is a sodium tetraphenylborate solution, the precipitant concentration and the number of drops are selected as the case may be, and preferably the concentration is 1 wt% to 30 wt%, and the number of drops is 1 drop to 20 drops.

Herein, the pH regulator and the masking agent can be packaged separately and prepared at the moment of use, and can also be prepared with the sodium tetraphenylborate or the solution thereof in advance. The sodium tetraphenylborate solution or the sodium tetraphenylborate solution containing the pH regulator and/or the masking agent is placed in a dropping bottle, and a fixed dropping amount is dropped into a measuring cup when in use.

Further research shows that the masking agent can be added into a water sample to be detected simultaneously with the sodium tetraphenylborate, or the masking agent can be added into the water sample to be detected first and then the sodium tetraphenylborate is added. Therefore, the interference of other ions to the result can be better reduced, and the accuracy is improved.

The addition of the pH regulator has no special requirements, and can be added with the sodium tetraphenylborate sequentially or simultaneously.

All solutions described herein are aqueous solutions unless otherwise specified.

In some embodiments, the measuring rod is provided with a scale on the measuring handle. In some embodiments, these scales represent concentration units, e.g., mg/L, ppm, mol/L, and the like. In some embodiments, the scales represent units of length, such as cm, mm, and the like. The potassium ion concentration in the water sample to be measured can be directly obtained by reading the scale on the measuring handle or obtained by conversion. Specific methods are described in the examples below.

In some embodiments, the color of the measurement marker is black or gray-black. Studies have shown that the shade of the color of the measuring marker, in relation to its depth, which is visible or invisible in the liquid to be measured, influences the final penetration depth of the measuring stick, i.e. the measurement result, and can therefore be selected and determined according to the actual measurement requirements. Among them, the preferred embodiment is that the color of the measuring marker is set to black or gray black.

In some embodiments, the measurement marker is a strip, a ribbon, or a disk.

In some embodiments, the material of the measuring handle and the measuring marker can be metal or plastic.

For ease of viewing, in some embodiments, the measurement marker is annular, cross-shaped, or otherwise shaped. Some specific forms of measurement markers are illustrated in the drawings.

In some embodiments, the measurement marker is further provided with a bulge or a wave stripe, so that the measurement marker is easier to observe in a potassium tetraphenylborate suspension formed in a liquid to be measured and is easier to judge a critical point when the critical point cannot be observed visually, and thus, the detection error can be reduced.

Further studies have found that when the measurement marker is a strip or ribbon, its width affects the final penetration depth, i.e. the assay result. In some embodiments, when the measurement marker is a strip or ribbon, its width ranges from 0.1mm to 5 mm.

In some embodiments, the measurement marker is a disk (e.g., black or gray black in color), or further a strip or ribbon having a color such as black or gray black disposed thereon.

In some embodiments, the radial direction of the measurement marker is perpendicular or substantially perpendicular to the length direction of the measurement shaft.

In some embodiments, the measurement container is a transparent material, such as plastic or glass.

In some embodiments, the measurement container is cylindrical, such as a cube or cylinder.

In some embodiments, the measurement container further carries one or more graduations, e.g., 10mL, 20mL, 50mL, etc.

In some embodiments, the measuring vessel is a measuring cylinder.

In some embodiments, the rapid potassium ion detection kit further comprises a measurement table, which records a conversion table or a calculation formula for further obtaining the potassium ion concentration in the water sample to be detected according to the scale obtained from the measurement handle. The measurement table can be obtained by measuring the potassium ion standard solution with known concentration. For the preparation of the measurement tables, reference is made to the examples below.

In some embodiments, the kit for rapidly detecting potassium ions further comprises a water sample measuring device for measuring the water sample to be detected, for example, the water sample measuring device can be selected from a straw with scales, a syringe, a measuring cup, a measuring cylinder and the like.

The potassium ion rapid detection kit can be used for simply, conveniently and rapidly detecting potassium ions in water. The potassium ion concentration in the water body to be detected can be obtained within minutes without professional experimental instrument and equipment and professional operation.

The invention also provides a rapid detection method of potassium ions, which comprises the following steps:

providing a precipitant, a measuring rod and a measuring container; wherein the precipitating agent comprises sodium tetraphenylborate or a solution thereof; the measuring rod comprises a measuring handle with scales and a measuring marker connected with one end of the measuring handle;

reacting the precipitant with a water sample to be detected to generate a liquid to be detected;

placing the liquid to be measured in the measuring container; inserting the measuring rod into the liquid to be measured, slowly detecting downwards, observing a measuring marker on the measuring rod downwards from the liquid level of the liquid to be measured until the measuring marker cannot be visually observed, and reading the scale which is intersected with the liquid level of the liquid to be measured on the measuring handle of the measuring rod at the moment;

and obtaining the potassium ion concentration in the water sample to be detected.

The precipitant, the measuring rod, the measuring container and the like involved in the rapid detection method for potassium ions of the present invention can be referred to the description of the rapid detection kit for potassium ions above.

In some embodiments, the concentration of potassium ions in the sample to be tested may be in the range of 1mg/L to 22 mg/L.

In some embodiments, when the concentration of potassium ions in the water sample to be tested is high, for example, more than 10mg/L, the potassium ions can be detected after being diluted with a blank water sample or purified water. In some embodiments, when the potassium ion concentration in the water sample to be detected is found to be too high in a specific detection process, a proper amount of blank water sample or purified water can be directly added for dilution, and detection is performed after uniform mixing, without re-detection. In some embodiments, when the potassium ion concentration in the water sample to be detected is found to be too low in a specific detection process, a proper amount of blank water sample containing potassium ions can be directly added, and the mixture is uniformly mixed and then detected without re-detection. Therefore, the water sample does not need to be replaced, the method can be simplified, the time is saved, and the working efficiency is improved.

The inventor also finds that when the pH of the solution to be detected is adjusted to 8-11, stable precipitation of potassium ions and sodium tetraphenylborate can be ensured, and the accuracy of the detection result can be improved.

In some embodiments, the water sample to be tested comprises freshwater aquaculture water, saltwater aquaculture water, seawater, aquaculture wastewater and other common water bodies needing to be measured for potassium ions.

The potassium ion rapid detection method can simply, conveniently and rapidly realize the detection of potassium ions in the water body. The potassium ion concentration in the water body to be detected can be obtained within minutes without professional experimental instrument and equipment and professional operation.

Specifically, in some embodiments, the method for rapidly detecting potassium ions of the present invention includes the following steps:

taking a water sample to be detected, and dividing the water sample into two conditions:

directly taking a water sample containing low-concentration potassium ions into a measuring cup, wherein the sampling amount can reach a higher scale, and can also be supplemented when insufficiency is found in the measuring process;

the method comprises the following steps of (1) accurately measuring a water sample containing high-concentration potassium ions (a graduated straw, a syringe, a measuring cup or a low-level scale mark on the measuring cup by directly adding the water sample), adding a blank water sample to a certain scale mark on the measuring cup, and recording the dilution times of the operations.

And adding a precipitator into the water sample to be detected, and uniformly mixing to prepare the liquid to be detected.

Measurement:

and inserting the measuring rod into the testing tube containing the liquid to be tested, slowly probing downwards, observing the measuring marker on the measuring rod until the measuring marker disappears, and reading the scale on the measuring handle at the liquid level.

And (3) calculating:

the scale on the measuring handle can be length unit (such as cm, mm, etc.) or potassium ion concentration unit (mg/L, ppm, mol/L, etc.), when the scale is length unit, a conversion table or a calculation formula is also needed, and the potassium ion concentration is obtained or calculated through the conversion table or the calculation formula. And multiplying the dilution times by the potassium ion concentration obtained in the process to obtain the potassium ion concentration of the water sample to be detected.

The kit and the detection method provided by the invention can realize the measurement of the potassium ion concentration by visually observing the change of the measurement mark and reading the scale on the measurement handle. In particular, for the kit of the invention,

1) the result can be judged by naked eyes based on the measuring marker on the measuring rod;

2) the measuring rod can drive the measuring marker to move up and down in the liquid to be measured through the measuring handle on the measuring rod, and a proper position is found to realize the purpose of detection;

3) the potassium ion concentration result can be directly or indirectly obtained by reading the scale of the measuring handle on the measuring rod; when the scale is the potassium ion concentration, the result can be directly read, and when the scale is the length unit, the result can be obtained by looking up the table or converting;

4) the measuring cup is provided with scales, and can realize dilution of a water sample to be measured by alone or matching with a water sample measuring device, so that the detection of potassium ions in a wider water body is realized;

5) the actual water sample determination requirement can be met by adjusting the thickness and the color depth of the measuring marker according to different water samples to be measured.

The invention has the beneficial effects that:

1) the field rapid detection is realized:

the invention can avoid the use of instruments and equipment such as an oven, a spectrophotometer, a balance and the like and avoid the complicated process of preparing the standard solution. The measurement time is reduced from hours to minutes, the detection cost is greatly reduced, the most important is that the operation difficulty of detection is low, professional analysis and detection personnel are not needed to operate, professional technical training is not needed, the on-site detection of an aquaculture site can be realized, farmers can adjust the concentration of potassium ions in water according to the result, the adjusted result can be detected on the site again after adjustment, and the method is very convenient.

2) Simple measuring method and wide detection range

The measuring method designed by matching with the detection kit has two characteristics (1) simple operation: taking a water sample, adding a precipitator, inserting a measuring rod, reading a result, and looking up a table or simply converting to obtain a result if necessary; (2) the large-range detection is realized: through simple dilution operation, can realize detection on a large scale (several mg/L to several thousand mg/L), and need not change detect reagent and detection device, solved different aquaculture water body to the different requirements of detection.

3) Can realize the rapid detection of unknown water bodies

The detection method has the important characteristic that when the potassium ion water with unknown concentration is detected, the detection result can be obtained quickly. The concentration range of potassium ions in different water bodies is wide, from a few ppm to thousands of ppm, and under the condition of uncertain concentration, the traditional detection method usually needs a plurality of times of experiments to obtain results. For example, when the potassium ion concentration is high, the precipitation method or the turbidity method may cause that the added precipitant is insufficient or exceeds the linear detection range, and the experiment failure needs to be determined again. In the invention, a proper amount of water sample can be measured by the water sample measuring device, the precipitation condition is observed after the precipitator is added, and blank water samples are gradually added according to the precipitation condition for dilution and observation until the dilution times are proper. When the concentration of the potassium ions in the water body is lower than the estimated concentration in the experiment, a water sample to be detected can be taken by the water sample measuring device and added into the water sample. Therefore, one-time success can be realized, and manpower, reagents and time are saved.

The invention has the advantages that:

1) the method is simple and convenient, realizes the field operation of potassium ion determination, and quickly gives out a detection result;

2) the cost of the test box or the detection cost is very low, so that the test box is convenient to popularize and apply;

3) wide detection range, and can meet the actual requirements of aquaculture and the like

4) The operation is flexible and convenient, the determination times can be reduced for samples with unknown concentration, and the determination result can be obtained quickly.

Drawings

FIG. 1 is a schematic diagram of a kit for rapid detection of potassium ions according to an embodiment of the present invention;

FIG. 2 is a schematic view of a measuring rod in a rapid potassium ion detection kit according to an embodiment of the present invention;

FIG. 3 is a schematic view (top view) of the measurement marker of the measurement rod in some of the rapid potassium ion detection kits according to the embodiments of the present invention;

FIG. 4 is a schematic diagram of the rapid detection of potassium ions according to an embodiment of the present invention;

wherein, 1 is a precipitator (placed in a reagent bottle); 2 is a measuring rod, 21 is a measuring handle of the measuring rod, and 22 is a measuring marker of the measuring rod; 3 is a measuring container, 4 is a measuring table and 5 is a water sample measuring device; and 6 is the liquid level of the liquid to be detected.

Detailed Description

The present invention will be described in further detail with reference to examples. But not to limit the invention thereto.

Unless otherwise specified, the concentration of each reagent in the invention is mass percentage concentration.

Please refer to fig. 1 and 2. FIG. 1 is a schematic diagram of a kit for rapid detection of potassium ions according to an embodiment of the present invention; it includes: precipitant 1 (placed in a reagent bottle) and measurement stick 2.

In some embodiments, the precipitant 1 is sodium tetraphenylborate or a solution thereof. The precipitant can be placed in a reagent bottle or plastic bag. In some embodiments, when the precipitant is sodium tetraphenylborate solution, the precipitant concentration and the number of drops are selected as the case may be, and preferably the concentration is 1 wt% to 30 wt%, and the number of drops is 1 drop to 20 drops. In some embodiments, the precipitating agent comprises an acid-base modifier or a solution thereof in addition to sodium tetraphenylborate or a solution thereof. The pH regulator can be selected from common acids (such as phosphoric acid, sulfuric acid, disodium hydrogen phosphate, citric acid, etc.), common bases (such as sodium hydroxide, sodium carbonate). In some embodiments, the precipitating agent includes, in addition to sodium tetraphenylboron or a solution thereof, a masking agent or a solution thereof for eliminating other ionic interference; the masking agent may be selected from disodium EDTA, isopropanol, and the like.

As shown in fig. 2, the measuring stick 2 includes a measuring handle 21 with a scale, and a measuring marker 22 connected to one end of the measuring handle 21. The measurement marker 22 connected to one end of the measurement handle 21 may be connected to one end of the measurement handle 21 in advance, or may be temporarily connected in use. The connection mode used can be fixed connection or movable connection, such as welding, riveting, bolt connection and the like. Can be set according to the needs.

In some embodiments, the measurement marker 22 is integrally formed with one end of the measurement shaft 21. In some embodiments, the material of the measuring handle 21 and the measuring marker 22 can be metal (e.g., iron wire) or plastic.

In some embodiments, the measuring stick has a scale on the measuring shaft 21. In some embodiments, these scales represent concentration units, e.g., mg/L, ppm, mol/L, and the like. In some embodiments, the scales represent units of length, such as cm, mm, and the like. The potassium ion concentration in the water sample to be measured can be directly obtained by reading the scale on the measuring handle or obtained by conversion. Specific methods are described below.

In some embodiments, the measurement marker 22 is black or gray-black in color.

In some embodiments, the measurement marker 22 is a strip, ribbon, or disk.

In some embodiments, the measurement marker is a ring, cross, or other shape, as can be seen in particular in fig. 3 a-g.

Please continue to refer to fig. 1. As shown in fig. 1, the kit for rapidly detecting potassium ions according to the embodiment of the present invention further includes a measuring container 3. In some embodiments, the measurement container is a transparent material, such as plastic or glass. In some embodiments, the measurement container is cylindrical, such as a cube or cylinder. In some embodiments, the measurement container further carries one or more graduations, e.g., 10mL, 20mL, 50mL, etc. In some embodiments, the measuring vessel is a measuring cylinder.

Please continue to refer to fig. 1. As shown in fig. 1, the kit for rapidly detecting potassium ions according to the embodiment of the present invention further includes a measurement table 4 (which is recorded with a conversion table or a calculation formula) for further obtaining the concentration of potassium ions in the water sample to be detected according to the scale obtained from the measurement handle 21. The measurement table 4 can be obtained by measuring the preparation of a standard solution of potassium ion of a known concentration. The preparation of the measurement tables can be found below.

Please continue to refer to fig. 1. As shown in fig. 1, the kit for rapidly detecting potassium ions in the embodiment of the present invention further includes a water sample measuring device 5, which is used for measuring a water sample to be detected, and can be selected from a straw with scales, a syringe, a measuring cup, a measuring cylinder, and the like.

The arrangement positions of the components in the kit are not particularly required.

Please refer to fig. 4. FIG. 4 is a schematic diagram of a specific application of the kit of the present invention in rapid detection of potassium ions in water. Wherein 2 is a measuring rod, 21 is a measuring handle of the measuring rod, and 22 is a measuring marker of the measuring rod; 3 is a measuring container, and 6 is the liquid level of the liquid to be measured. The specific detection method comprises the following steps:

taking the kit, taking a proper amount of water sample to be detected, and reacting the water sample to be detected with a proper amount of precipitator to generate a liquid to be detected; placing the solution to be measured in a measuring container 3 (or directly carrying out reaction in the measuring container); inserting the measuring rod 2 into the liquid to be measured, slowly detecting downwards, observing a measuring marker 22 on the measuring rod downwards from the liquid level 6 of the liquid to be measured until the measuring marker 22 cannot be observed visually, and reading the scale which is intersected with the liquid level 6 of the liquid to be measured on the measuring handle 21 of the measuring rod at the moment; if the scale represents the potassium ion concentration in the water sample to be detected, the potassium ion concentration in the water sample to be detected can be directly obtained; if the scale indicates the depth of the measuring marker extending below the liquid level of the liquid to be measured, the potassium ion concentration in the water sample to be measured can be obtained through a measuring table 4 (a conversion table or a calculation formula).

Surprisingly, it has been found that the method of the present invention provides a higher degree of accuracy when controlling the concentration of potassium ions in the solution to be tested to be in the range of 1mg/L to 22 mg/L. That is to say, the potassium ion concentration in the water sample to be detected obtained by the method of the invention is closer to the true value.

Generally, the concentration of potassium ions in the water body is not lower than 0.8mg/L, and when a special requirement is to determine the low-concentration potassium ion water body (the concentration is lower than 1.0mg/L), two schemes can be selected:

one is to select a deeper measuring vessel and a measuring stick with a longer measuring handle; and secondly, the measuring rod is replaced, and the line of the measuring marker on the replaced measuring rod is thinner and the color of the measuring marker is lighter.

When the potassium ion concentration in the solution to be detected is higher than 22mg/L (or when the potassium ion concentration is higher than 10mg/L for improving the detection accuracy), the solution can be quantitatively diluted and then detected (namely, a water sample to be detected is quantitatively taken, purified water is quantitatively added, and the solution to be detected is quantitatively diluted), so that the potassium ion concentration in the solution to be detected is in the range of 1mg/L-22 mg/L. For the solution to be tested with uncertain potassium ion concentration range, a stepwise quantitative dilution process can be adopted (see the examples). The operation has the advantages that not only can more accurate detection results be obtained, but also the detection process is simpler and more convenient, namely, the water sample to be detected does not need to be replaced for re-detection; in addition, the detection reagent (precipitator) is saved, and the detection time is saved.

Example 1

A precipitant: aqueous solution of sodium tetraphenylborate (10 wt%).

Measuring a rod: as shown in fig. 4, the measuring handle 21 is provided with scales, and the scales are length units; the scale at the joint of the measuring handle 21 and the measuring marker 22 is 0, the highest scale is 20cm, and the unit of the smallest scale is 1 mm; the measuring marker 22 specifically comprises a disk whose radial direction is perpendicular to the measuring shaft 21 and two 2cm long perpendicularly intersecting black iron wires (wire diameter 1mm) provided on the disk, which are used as measuring markers during the test.

Measuring a cup: the cylindrical glass is made of transparent glass, the diameter is 3cm, the depth is 25cm, and the highest scale mark is 20 cm.

Production process of measurement table (conversion table):

respectively preparing potassium ion standard solutions: 1mg/L, 100mg/L, 1000 mg/L. Pouring 1mg/L of potassium ion standard solution into a measuring cup to a 20cm scale mark, putting a measuring rod to enable the liquid level to be intersected with the 20cm scale mark on the measuring handle 21, observing the measuring mark 22 from the upper end of the liquid level of the measuring cup downwards through the solution, adjusting the potassium ion standard solution to be 100mg/L and 1000mg/L until the measuring mark 22 just disappears in a sight line, recording the adjusting process, and converting the concentration of potassium ions in the measuring cup at the moment to obtain the concentration of the corresponding potassium ions at the 20cm scale mark on the measuring handle 21. The concentrations of potassium ions corresponding to other heights on the measurement shaft 21 were measured in sequence in the above-described manner. Specific results are shown in table 1 below:

TABLE 1

The measuring handle 21 is provided with a reading scale (cm)	Concentration of potassium ion (mg/L)
		1	22
2	11
		3	7.3
4	5.5
		5	4.4
6	3.6
		8	2.8
10	2.2
		11	2.0
14	1.6
		16	1.4
18	1.2
		20	1.1

1) Determining a water sample 1 to be detected:

adding a water sample to be detected with a scale mark of 1-20 cm into a measuring cup, dripping 8 drops of precipitator into the measuring cup, uniformly stirring the mixture, and staying for three minutes to obtain a liquid to be detected; inserting the measuring rod 2 into the liquid to be detected, slowly downwards detecting, and observing the measuring marker on the measuring rod from the liquid level of the liquid to be detected downwards, wherein the measuring rod can be properly lifted up or downwards detected until the measuring marker cannot be visually detected (the measuring marker disappears from the sight); and reading the scale which is intersected with the liquid level of the liquid to be measured on the measuring handle of the measuring rod at the moment and is 8.2 cm. As shown in Table 1 above, the concentration of potassium ions in the water sample 1 to be tested is 2.8 mg/L.

Meanwhile, the water sample 1 to be detected is detected by adopting a tetraphenylboropotassium gravimetric method (determination of total nitrogen, phosphorus and potassium contents of NY/T1977-.

Therefore, the method of the invention is close to the result obtained by the method of the prior art, and the error is not more than 5%.

2) And (3) determining the water sample 2 to be detected:

and taking a water sample 2 to be detected, and detecting by adopting the method of the water sample 1 to be detected respectively. Wherein, the potassium ion concentration in the water sample 2 to be measured is 1.1mg/L by adopting the method of the invention, and the result measured by adopting the method of the prior art is 0.74 mg/L. As can be seen, the potassium ion concentration in the water sample 2 to be detected is lower than 1.2mg/L, so that the method has certain error, but still is within an acceptable range.

Further, the following two methods can be arbitrarily selected:

the method comprises the following steps: and (3) replacing the measuring cup (the depth of the replaced measuring cup exceeds 30cm), replacing the measuring rod (the scale of the measuring handle of the replaced measuring rod is 30cm at most), measuring according to the measuring process of the water sample 1 to be measured, and inquiring the measuring result according to the table 2. And adding a potassium ion standard solution with the concentration of 100mg/L into the solution to be detected, recording the added volume, and detecting by using the method, wherein the potassium ion concentration in the water sample 2 to be detected is measured to be 0.7 mg/L. It can be seen that the results obtained by the method of the present invention are close to those obtained by the prior art method, and the error is not more than 6%.

TABLE 2

The method 2 comprises the following steps: and replacing the measuring rod, namely replacing the vertically crossed black iron wire (the diameter of the iron wire is 1mm) serving as the measuring marker on the measuring rod with a vertically crossed gray iron wire (the diameter of the iron wire is 0.5mm), namely, the color of the replaced measuring marker is light and the diameter of the iron wire is thinner.

The measurement table is reproduced as shown in Table 3 according to the above-mentioned process

TABLE 3

The measuring handle 21 is provided with a reading scale (cm)	Concentration of potassium ion (mg/L)
		1	10.0
2	5.0
		3	3.3
4	2.5
		5	2.0
6	1.7
		8	1.3
10	1.0
		11	0.9
14	0.7
		16	0.6
18	0.6
		20	0.5

And (4) determining according to the determination process of the water sample 1 to be determined, and inquiring the determination result according to the table 3. The potassium ion concentration in the water sample 2 to be measured at this time is 0.7 mg/L. It can be seen that the results obtained by the method of the present invention are close to those obtained by the prior art method, and the error is not more than 6%.

3) And (3) determining a water sample to be detected:

and taking a water sample 3 to be detected, and detecting by adopting the method of the water sample 1 to be detected respectively. Wherein, the potassium ion concentration in the water sample 3 to be measured is 22mg/L by adopting the method of the invention, and the result measured by adopting the prior art method is 30 mg/L. As can be seen, the potassium ion concentration in the water sample 3 to be detected is higher than 22mg/L, so that the method has certain error, but still is within an acceptable range.

And (3) measuring the water sample to be measured again to a 5cm scale mark of the measuring cup, adding purified water to the liquid to be measured to a 20cm scale mark, properly stirring the liquid to be measured by using the measuring rod until the liquid is uniform, detecting the liquid by using the method, wherein the measured potassium ion concentration in the measuring cup is 7.3mg/L, and multiplying the value by the dilution factor 4 to obtain the potassium ion concentration of the water sample 3 of 29.2 mg/L. It can be seen that the results obtained by the method of the present invention are close to those obtained by the prior art method, and the error is not more than 3%.

Example 2

The measuring cup and the precipitating agent are the same as those in example 1.

The measuring bar is the same as in example 1 except for the scale on the measuring shaft 21.

In this embodiment, the scale on the measurement handle 21 is set to the potassium ion concentration (mg/L).

The calibration method of the scale on the measuring handle 21 in this embodiment is basically the same as that in embodiment 1, except that: potassium ion standard solutions (1-20mg/L) with different concentrations are prepared, and the scales on the measuring handle 21 are calibrated according to the detection method of the embodiment 1.

In the detection process, the length scale on the measuring handle 21 corresponding to each potassium ion standard solution is recorded, and the corresponding relation with the reading scale (cm) on the measuring handle 21 of the embodiment 1 is shown in the following table 4:

TABLE 4

Concentration of Potassium ion (mg/L)	Corresponding Length Scale (cm) in example 1
		1	22.0
2	11.0
		3	7.3
4	5.5
		5	4.4
7	3.1
		9	2.4
12	1.8
		18	1.2
20	1.1

Determining a water sample 1 to be detected: the determination process is the same as that in the embodiment 1, the scale of the intersection of the measuring handle of the measuring rod and the liquid level of the liquid to be determined is read to be between 2mg/L and 3mg/L, and the potassium ion concentration in the water sample 1 to be determined is estimated to be 2.5 mg/L.

Example 3

The same as in example 1. The following conversion formula is adopted:

determining a water sample 1 to be detected: the measuring process is the same as that in example 1, the scale intersecting with the liquid level of the liquid to be measured on the measuring handle of the measuring stick at the moment is read to be 8.2cm, and the formula is substituted, so that the potassium ion concentration in the water sample 1 to be measured is obtained to be 22/8.2-2.7 mg/L.

Example 4

The same as example 1, wherein the measuring cup is provided with a scale (0-20 cm scale units cm from the bottom upwards).

The water sample 4 was assayed: pouring a water sample 4 into a measuring cup to a scale mark of 1cm, adding 5 drops of precipitator, adding a blank water sample (Wahaha purified water) to a scale mark of 10mL of the measuring cup, uniformly stirring the measuring rod, standing for 3min, measuring after stirring, intersecting the measuring handle of the measuring rod with the liquid level at a position of 3cm, and looking up a table 1 to obtain the potassium ion concentration in the water sample at the moment of 7.3 mg/L. In sample 4, the concentration of potassium ions was 7.3mg/L × dilution factor was 7.3mg/L × 10 was 73 mg/L.

The water sample 5 was tested: according to the determination process of the water sample 5, the measurement handle of the measurement rod intersects with the liquid level at a position less than 1cm, the blank water sample is continuously added to the measurement cup at a position of 20cm, at this time, the measurement handle of the measurement rod intersects with the liquid level at a position of 1.5cm, the calculation formula in the embodiment 3 can be adopted, and the potassium ion concentration in the water sample is 14.7mg/L, and the potassium ion concentration in the water sample 5 is 14.7mg/L multiplied by the dilution factor, 14.7mg/L multiplied by 20, 294 mg/L.

Example 5

As in example 1, wherein the measurement markers of the measurement stick are selected from the following, see in particular fig. 3:

as shown in c of fig. 3, the measuring mark is a circular ring, a cross-shaped intersecting line (a metal wire or a wire made of other materials, the color is black) is arranged in the middle of the circular ring, and a measuring handle of the measuring rod is connected with the edge of the circular ring and is perpendicular to the plane of the circular ring.

As shown in e in fig. 3, the chassis is a silver white metal disc, a cross-shaped intersection line (engraved on the metal disc and the scribed line covered with black paint) is arranged in the middle, the measuring handle of the measuring rod is connected with the edge of the disc, and the plane of the fish ring is vertical.

As shown in f of fig. 3, the measuring marker is a quadrangle with a cross-shaped intersection line (a metal wire or other material wire, black in color) in the middle, and the measuring handle of the measuring rod is connected with the edge of the quadrangle and is perpendicular to the plane of the ring.

Example 6

The same as example 1, wherein the measuring cup has 25mL and 50mL marks and is equipped with 1 graduated glass pipette, the maximum measuring range of the glass pipette is 1mL, and the minimum scale is 0.1 mL.

The water sample 6 was tested: sucking 1mL of water sample 6 by using a suction pipe, putting the water sample into a measuring cup, diluting the water sample to 50mL of scale mark by using deionized water, adding 5 drops of precipitator, uniformly stirring the mixture by using a measuring rod, standing the mixture for 3min, stirring the mixture again, measuring the mixture until the measuring rod reaches the bottom, still seeing a measuring mark, sucking 1mL of water sample 4 by using the suction pipe, putting the mixture into the measuring cup, uniformly stirring the mixture by using the measuring rod, standing the mixture for 3min, stirring the mixture again, and measuring the mixture, wherein the measuring handle of the measuring rod and the liquid level intersect at 12 cm. It is estimated from Table 1 in example 1 that the potassium ion concentration in the liquid at this time was about 1.8mg/L, and thus the potassium ion concentration in sample No. 6 was 1.8 mg/L.times.the dilution factor was 1.8 mg/L.times. 50/2 was 45mg/L

The water sample 7 was tested: and (3) measuring the same water sample 6, sucking 0.1mL of water sample 5 by using a suction pipe, putting the water sample into a measuring cup, diluting the water sample to 50mL of scale mark by using deionized water, adding 5 drops of precipitator, uniformly stirring the mixture by using a measuring rod, standing the mixture for 3min, stirring the mixture again, and measuring the mixture, wherein the measuring handle of the measuring rod is intersected with the liquid level at 4 cm. It is estimated from Table 1 in example 1 that the potassium ion concentration in the liquid at this time was about 5.5mg/L, and thus the potassium ion concentration in sample 7 was 5.5mg/L × dilution factor of 5.5mg/L × 50 ÷ 0.1 ═ 2750mg/L

In the embodiment, the glass straw with scales can be replaced by a syringe, a measuring cylinder and the like.

Example 7

As in examples 1 and 5, where the cross-shaped measurement marker is used, the line width may vary, for example from 0.1mm to 5mm, and the color may also vary between black and grey.

When the above-mentioned situation changes, it is necessary to newly prepare the conversion table in example 1, the scale of the potassium ion concentration on the measurement stem in example 2, or the conversion formula in example 3.

Example 8

In embodiments 1 and 5, the cross-shaped measurement marker can be replaced by other shapes, such as two or more intersecting line segments or curves, for easy observation. For example, d and g in fig. 3.

Example 9

The concentration of the precipitant and the number of drops in example 1 are selected as appropriate, for example, from 1% to 30% and from 1 to 20 drops.

Example 10

The precipitant in example 1 may also be a sodium tetraphenylborate solid directly, or a mixture of sodium tetraphenylborate and sodium chloride (sodium tetraphenylborate is relatively loose, and it is difficult to measure and quantify it with a common spoon) may be used for convenience, and the ratio of sodium tetraphenylborate in the mixture is, for example, 1% to 70%.

Example 11

The precipitant in example 1, example 9, and example 10 can also be added with acid-base regulator according to the characteristics of the water sample, and the acid-base regulator can be selected from sodium hydroxide, disodium hydrogen phosphate, etc., and can be independently prepared into solution and put into a dropping bottle for practical use, and the precipitant can be used together with the sodium tetraphenylborate or before or after the sodium tetraphenylborate.

Example 12

In the precipitating agents in the embodiments 1, 9 and 10, masking agents can be added according to the characteristics of the water sample to avoid other ions from interfering the detection, and the optional masking agents are EDTA disodium salt, phosphoric acid and the like. The masking agent may be added simultaneously with or prior to the sodium tetraphenylborate.

Although the invention has been described in detail hereinabove with respect to a general description and specific embodiments thereof, it will be apparent to those skilled in the art that modifications or improvements may be made thereto based on the invention. Accordingly, such modifications and improvements are intended to be within the scope of the invention as claimed.

Claims

1. A potassium ion rapid detection kit comprises:

or also a measuring vessel.

2. The kit for rapidly detecting potassium ions according to claim 1, wherein the precipitant further comprises one or more of an acid-base modifier or a solution thereof, a masking agent for eliminating interference of ions other than potassium ions or a solution thereof, and a solid diluent; the solid diluent is preferably sodium chloride.

3. The potassium ion rapid detection kit according to claim 1, wherein the precipitant is a mixture of sodium tetraphenylborate solid and sodium chloride; preferably, the proportion of the sodium tetraphenylborate in the mixture is 1 wt% -70 wt%.

4. The potassium ion rapid detection kit according to any one of claims 1 to 3, wherein the color of the measurement marker is black or gray-black; and/or the presence of a gas in the gas,

the measuring marker is a strip, a belt or a disc; and/or the presence of a gas in the gas,

the measuring marker is annular, cross-shaped or other shapes; and/or the presence of a gas in the gas,

and the measuring marker is also provided with a bulge or a wave stripe.

5. The potassium ion rapid detection kit according to any one of claims 1 to 4, wherein the potassium ion rapid detection kit further comprises a measurement table for further obtaining the potassium ion concentration in the water sample to be detected according to the scale obtained from the measurement handle; and/or the presence of a gas in the gas,

the potassium ion rapid detection kit further comprises a water sample measuring device.

6. A method for rapidly detecting potassium ions comprises the following steps:

7. The method for rapidly detecting potassium ions according to claim 6, wherein the precipitating agent is the same as in claim 2 or 3.

8. The method for rapidly detecting potassium ions according to claim 6 or 7, wherein the measurement marker is the same as in claim 4.

9. The method for rapidly detecting potassium ions according to any one of claims 6 to 8, wherein the concentration of potassium ions in the water sample to be detected is controlled within the range of 1mg/L to 22 mg/L.

10. The method for rapidly detecting potassium ions according to any one of claims 6 to 9, wherein the pH of the solution to be detected is adjusted to be in the range of 8 to 11.