Portable developing test ball for rapidly detecting trivalent antimony in water body and preparation method of portable developing test ball

Abstract

The invention discloses a portable developing test ball for rapidly detecting trivalent antimony in a water body and a preparation method of the portable developing test ball, and belongs to the technical field of environment detection. The color developing test ball is composed of graphene, sodium alginate, a sulfydryl modified group and a rhodamine B color developing agent. The graphene is used for adsorbing trivalent antimony in a water body; sodium alginate is used as a carrier material and is compounded with graphene and sulfydryl modification groups to form a gelatinous material, the gelatinous material has the effects of mechanically supporting and adsorbing antimony ions, and a stable sphere structure is formed through crosslinking of a calcium salt solution; the sulfydryl modified group is combined with graphene or sodium alginate through a chemical reaction to form a functionalized adsorption interface, and sulfydryl can be subjected to a strong coordination reaction with trivalent antimony, so that the selectivity of the test ball to the trivalent antimony is remarkably improved. A rhodamine B color developing agent is used as a color developing material, and is subjected to a specific reaction with trivalent antimony, so that the rhodamine B color developing agent shows amaranth. The test ball realizes efficient adsorption and color development detection of trivalent antimony in a water body through the synergistic effect of all the components.

Description

Technical Field

[0001] The present invention relates to the technical field of environmental detection, and particularly relates to a portable colorimetric test ball for rapid detection of trivalent antimony in water and a preparation method thereof. Background Art

[0002] With the rapid development of the electronics, metallurgy, and chemical industries, industrial pollution has intensified, leading to an increasingly serious problem of antimony (Sb) pollution in water bodies. Among them, trivalent antimony (Sb 3+ ) has received extensive attention due to its high toxicity. Trivalent antimony not only poses a serious threat to aquatic organisms and ecosystems but also harms human health through drinking water. According to the "Guidelines for Drinking Water Quality" of the World Health Organization (WHO), the concentration of antimony in water should not exceed 5 μg / L. Therefore, the detection of antimony has become an important topic in the field of environmental monitoring.

[0003] The existing detection technologies for trivalent antimony mainly include the following several types: 1. Spectral analysis methods: such as atomic absorption spectrometry (AAS) and inductively coupled plasma mass spectrometry (ICP-MS). These methods have high sensitivity and high precision and can distinguish different valence states of antimony (such as Sb 3+ and Sb 5+ ).

[0004] 2. Chromatographic analysis methods: liquid chromatography (HPLC) and gas chromatography (GC) are used to separate different forms of antimony and can accurately determine the antimony content in complex samples.

[0005] 3. Colorimetric detection method: The colorimetric detection method is a detection means based on a chemical color reaction. By reacting a color reagent with trivalent antimony (Sb³⁺) to produce a color change, the concentration of antimony can be quickly judged.

[0006] 4. Electrochemical detection method: The application of electrochemical sensors in the detection of trivalent antimony is gradually increasing, with high sensitivity and portability.

[0007] However, there are many problems and deficiencies in the existing detection methods. For example: 1. Poor portability: The existing technologies (such as spectral methods and chromatographic methods) require expensive instrument equipment, complex operations, and the detection process can only be completed in the laboratory and cannot be applied to on-site field detection. After field sampling, the water sample needs to be sent back to the laboratory for analysis, which is not only time-consuming and laborious but also may cause oxidation or loss of trivalent antimony in the water sample, affecting the detection results.

[0008] 2. Insufficient sensitivity and selectivity: Compared with spectroscopic analysis and chromatographic analysis, although colorimetric methods and electrochemical sensors have certain advantages in on-site detection. However, existing colorimetric detection methods generally require complex reagent preparation and experimental operations, and are usually in liquid phase systems, which are not convenient for long-term storage or on-site application. Moreover, colorimetric methods are easily interfered by other metal ions (such as iron, copper, etc.) in water samples; electrochemical methods have high requirements for equipment accuracy, are easily affected by environmental conditions, resulting in easy damage to the equipment, and due to high requirements for the manufacturing process of sensors, the cost is relatively high, so large-scale popularization has not been achieved yet.

[0009] 3. Poor real-time performance: Existing methods (especially laboratory detection methods) are difficult to quickly obtain detection results and cannot meet the rapid screening requirements for water pollution.

[0010] 4. Complicated operation: Some colorimetric methods require adjusting the pH or adding multiple chemical reagents, and the experimental process is cumbersome, which is not suitable for non-professional personnel to operate.

[0011] Therefore, there is an urgent need for a technology that is portable, easy to operate, highly sensitive and can quickly detect trivalent antimony in water on-site. Summary of the Invention

[0012] The purpose of the present invention is to provide a portable colorimetric test ball for rapid detection of trivalent antimony in water and its preparation method, so as to solve the problems of poor portability, long detection time, complicated operation, insufficient sensitivity and selectivity in the background technology, realize the on-site rapid detection of trivalent antimony in water, and is particularly suitable for pollution screening in the field environment.

[0013] To achieve the above purpose, the present invention provides a preparation method of a portable colorimetric test ball for rapid detection of trivalent antimony in water, which specifically includes the following steps: Step 1. Preparation of solutions Prepare rhodamine B solution, graphene solution, sodium alginate solution and sodium thioglycolate solution; Step 2. Formation of composite material solution Ultrasonically treat the graphene solution, and after dispersing it evenly, add the graphene solution to the sodium alginate solution and mix evenly to obtain a mixed solution of graphene and sodium alginate; then add the sodium thioglycolate solution to the mixed solution of graphene and sodium alginate, and stir evenly to form a composite material solution; Step 3. Spherification and crosslinking Drop the composite material solution into a bath containing calcium salt solution, and the calcium ions react with the sodium alginate in the composite material solution to crosslink and solidify into spheres. After the spheres are soaked in the calcium salt solution, take out the spheres and immerse them in the sodium alginate solution. After coating with sodium alginate, the spheres are immersed in the calcium salt solution again and undergo a crosslinking reaction to form composite spheres; Step 4: Preparation of the color-developing test balls Put the obtained composite spheres into a rhodamine B solution, take them out after soaking, and place them in a desiccator for natural drying to obtain the color-developing test balls.

[0014] Preferably, in Step 1, the specific preparation method of the rhodamine B solution is: dissolve 47.90 mg of rhodamine B powder in 100 mL of deionized water to prepare the rhodamine B solution.

[0015] Preferably, in Step 1, the specific preparation method of the graphene solution is: dissolve 1 g of graphene oxide powder in 100 mL of deionized water to obtain a graphene oxide solution, and then use ultrasonic treatment for 1.5 hours to obtain the graphene solution.

[0016] Preferably, in Step 1, the specific preparation method of the sodium alginate solution is: add 2 g of sodium alginate powder to 100 mL of deionized water and stir to dissolve to obtain the sodium alginate solution.

[0017] Preferably, in Step 1, the specific preparation method of the sodium thioglycolate solution is: dissolve 3 g of sodium thioglycolate powder in 100 mL of deionized water to prepare the sodium thioglycolate solution.

[0018] Preferably, in Step 3, the calcium salt solution is a calcium chloride solution.

[0019] Preferably, the specific preparation method of the calcium chloride solution is: dissolve 1.665 g of calcium chloride in 100 mL of deionized water to prepare the calcium chloride solution.

[0020] Preferably, in Step 4, the soaking time is 2 h and the drying temperature is less than 50 °C.

[0021] The present invention also provides the color-developing test balls prepared by the above-mentioned preparation method.

[0022] Therefore, a portable color-developing test ball for rapid detection of trivalent antimony in water and its preparation method provided by the present invention, when the prepared test ball is applied to water bodies polluted by heavy metals, can significantly improve the portability, sensitivity and real-time performance of the detection of trivalent antimony in water bodies. Its main technical effects are as follows: (1) Portability: The test ball is small in volume and light in weight, can be used portably, is suitable for rapid detection in the field environment, and does not require complex instrument equipment; (2) Real-time performance: The test ball can complete the color-developing reaction within a few minutes during on-site detection, quickly judge whether the trivalent antimony exceeds the standard, and meet the timeliness requirements of pollution screening; (3) Simple operation: The test process does not require adjusting the pH or adding additional reagents, is simple to operate, and can be used by non-professionals; (4) Sensitivity and selectivity: The detection sensitivity of the test ball for trivalent antimony can reach 5 μg / L, with good selectivity and not significantly interfered by other metal ions in the water body. (5) Economy: The test ball is prepared with low-cost materials, and the production and detection costs are significantly reduced compared with the existing laboratory detection methods. (6) Broad application prospects: The test ball of the present invention is suitable for pollution screening of various water bodies such as drinking water, surface water, and groundwater, and can be widely applied in the fields of environmental monitoring, water quality assessment, and pollution control.

[0023] The technical solution of the present invention will be further described in detail below through the drawings and embodiments. Description of the Drawings

[0024] Figure 1 It is the preparation flow chart of the colorimetric test ball in the embodiment of the present invention. Figure 2 It is the use flow chart of the colorimetric test ball prepared in the embodiment of the present invention. Detailed Embodiments

[0025] In the present invention, graphene, sodium alginate, mercapto-modified group, and rhodamine B color reagent are integrated into the test ball. The colorimetric test ball is placed in a 1 L heavy metal polluted water sample. Through the synergistic effect of each component, the test ball realizes the efficient adsorption and colorimetric detection of trivalent antimony (Sb 3+ ) in the water body. If the concentration of trivalent antimony exceeds 5 μg / L, the colorimetric result is purple-red. Among them, the test ball realizes the rapid detection of trivalent antimony through the following main structures and functions: Graphene: It is used to adsorb trivalent antimony (Sb 3+ ) in the water body to improve sensitivity and selectivity. Graphene has a large specific surface area and excellent adsorption performance. As the main adsorption material, it can effectively bind trivalent antimony ions in water.

[0026] Sodium alginate: As a carrier material, it is compounded with graphene and mercapto-modified group to form a gel-like material, which plays a role in mechanical support and adsorption of antimony ions. A stable gel sphere structure is formed by cross-linking with a calcium salt solution.

[0027] Mercapto-modified group: The mercapto (-SH) has a strong coordination ability for trivalent antimony. By chemically modifying and introducing mercapto, the selectivity of the test ball for trivalent antimony can be significantly improved. The mercapto-modified group is combined with graphene or sodium alginate through a chemical reaction to form a functionalized adsorption interface.

[0028] Rhodamine B color reagent: As a colorimetric material, it reacts specifically with trivalent antimony to show purple-red. This colorimetric reaction is sensitive, fast, and the change can be directly observed with the naked eye.

[0029] The present invention also provides a method for preparing a portable test ball based on a color reaction, as follows: (1) Solution preparation: Rhodamine B solution is used for color development. The graphene oxide solution is ultrasonically treated for 1.5 hours to improve the dispersion uniformity. The sodium alginate solution is fully stirred until completely dissolved.

[0030] (2) Formation of the composite material: The graphene oxide solution is mixed with the sodium alginate solution, and the sodium thioglycolate solution is added. The mixed solution is ultrasonically treated for 20 minutes to ensure the uniform combination of each component.

[0031] (3) Ball formation and crosslinking: The mixed solution is slowly dropped into the calcium salt solution by titration. In the calcium salt solution, sodium alginate forms stable spheres through a crosslinking reaction and is soaked for 30 minutes to ensure complete gelation.

[0032] Among them, the titration method can be replaced by a spraying method: The composite solution is atomized through a spraying system (such as a spray tower, a spray gun, or an ultrasonic nebulizer). The spraying system can form tiny droplets of the liquid ejected through the action of compressed air or ultrasonic waves, and the spray droplets form spheres in the calcium salt solution. This method can form more uniform spherical particles. The size and uniformity of the spray droplets depend on the nozzle size of the sprayer, the liquid flow rate, and the air flow rate.

[0033] (4) Loading the color developer: The generated test balls are soaked in the Rhodamine B solution for 2 hours to allow the color developer to be fully adsorbed inside and outside the balls. Subsequently, the test balls are taken out and naturally dried at a temperature below 50 °C.

[0034] (5) Drying and packaging: The dried test balls are individually packaged or packaged in groups for easy carrying and on-site use, while preventing moisture and contamination.

[0035] The technical solutions of the present invention are further described below with reference to the accompanying drawings and embodiments. It should be understood that these embodiments are only used to illustrate the present invention and not to limit the scope of the present invention. Any other changes, modifications, substitutions, combinations, and simplifications made without departing from the spirit and principle of the present invention shall be equivalent replacement methods and shall be included in the protection scope of the present invention. In addition, it should be understood that after reading the content of the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the appended claims of this application and belong to the protection scope of the present invention.

[0036] References to "embodiments" in this document mean that the specific features, structures, or characteristics described in connection with the embodiments may be included in at least one embodiment of the present application. The term "embodiment" appearing in various positions in the specification does not necessarily refer to the same embodiment, nor is it particularly limited to its independence or relevance to other embodiments. In principle, in the present application, as long as there is no technical contradiction or conflict, the various technical features mentioned in each embodiment can be combined in any way to form corresponding implementable technical solutions.

[0037] Unless otherwise defined, the meanings of the technical terms used in this document are the same as those commonly understood by those skilled in the technical field to which this application belongs; the use of the relevant terms in this document is only for describing specific embodiments and is not intended to limit this application.

[0038] Unless otherwise specified in the present invention, the reagents, instruments, equipment, etc. used are the reagents, instruments, and equipment commonly used by those skilled in the art in this field.

[0039] Embodiment In this embodiment, a colorimetric test ball is supported by integrating graphene, sodium alginate, a mercapto-modified group, and a rhodamine B color reagent into the test ball. For the specific manufacturing flow chart, see Figure 1 as shown. The process is as follows: (1) Preparation of rhodamine B solution: Dissolve 47.90 mg of rhodamine B powder in 100 mL of deionized water to prepare a rhodamine B solution.

[0040] (2) Preparation of graphene solution: Dissolve 1 g of graphene oxide powder in 100 mL of deionized water to obtain a graphene oxide solution, and then use ultrasonic treatment for 1.5 hours to obtain a graphene solution.

[0041] (3) Dissolution of sodium alginate: Add 2 g of sodium alginate powder to 100 mL of deionized water and stir to dissolve to obtain a sodium alginate solution.

[0042] (4) Preparation of sodium thioglycolate solution: Dissolve 3 g of sodium thioglycolate in 100 mL of deionized water to obtain a sodium thioglycolate solution.

[0043] (4) Formation of the composite material: First, use ultrasonic treatment on the graphene solution (for 20 minutes) to help disperse the graphene evenly and promote the composite effect. Slowly add 100 mL of the graphene solution to 100 mL of the sodium alginate solution and mix evenly. At this time, the graphene will interact with the sodium alginate molecules through electrostatic or hydrogen bond interactions to form a composite material. Add 100 mL of the sodium thioglycolate solution to the composite solution of sodium alginate and graphene and stir evenly. The mercapto group can improve the adsorption capacity for trivalent antimony through a coordination reaction with antimony ions.

[0044] (5)Spheroid formation and crosslinking: Using the titration method, the composite material solution was slowly dropped into a calcium chloride bath using a dropper (preparation of calcium chloride solution: 1.665 g of calcium chloride powder was added to 100 mL of deionized water to prepare a 0.15 mol / L calcium chloride solution). Calcium ions (Ca²⁺) would react with sodium alginate in the composite material solution to form a crosslinking reaction and quickly solidify into spheres. The spheres were soaked in the calcium salt solution for 30 minutes to ensure complete gelation. To enable the outer part of the spheres to carry more color-developing agent, the formed composite spheres were immersed again in a separate sodium alginate solution (the same sodium alginate solution as prepared before) to ensure a thin layer of solution was evenly coated on the surface of each sphere. The coated spheres needed to be soaked in the calcium chloride solution again. Calcium ions would react with the carboxyl groups (-COO⁻) in the sodium alginate solution to quickly form a strong outer shell. The spheres should be soaked in the calcium salt solution again for 30 minutes to ensure the outer shell was fully crosslinked and a firm protective layer was formed.

[0045] (6)Loading color-developing agent: The solidified composite spheres were placed into a rhodamine B solution, and using the soaking method, they were stirred to enable the surface or interior to fully adsorb the color-developing agent. The soaking time was 2 hours to ensure full adsorption of the color-developing agent.

[0046] (7)Drying and encapsulation: The spheres loaded with rhodamine B were taken out and dried in a dryer at 30 °C to avoid degradation of the color-developing agent. The dried test spheres could be individually packaged or packaged in small bags for convenient use. Attention should be paid to moisture-proof and anti-pollution during packaging.

[0047] As Figure 2 shown, the usage steps of the color-developing test spheres prepared in this example are as follows: The test spheres were directly placed into the heavy metal-polluted water sample to be detected (1 L). The color-developing agent on the surface of the test spheres reacted with trivalent antimony in the water sample. After soaking for 5 minutes, the spheres showed a purplish red color. Through experimental verification, the test spheres of the present invention showed good color-developing effects in different concentrations of trivalent antimony solutions, and the color-developing intensity was positively correlated with the concentration.

[0048] Therefore, the test spheres prepared by the present invention are small in volume, light in weight, convenient to carry around, suitable for use in the field environment, and do not require additional reagents and complex operations. The color-developing reaction time is short, and the detection can be completed in only a few minutes; at the same time, the detection limit is as low as 5 μg / L, it has high selectivity for trivalent antimony, is not interfered by other metal ions, and has high sensitivity and selectivity. It can meet the requirements of rapid screening of heavy metal pollution in the field of environmental monitoring and has broad application prospects.

[0049] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions of the present invention or make equivalent replacements, and these modifications or equivalent replacements do not enable the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for preparing a portable colorimetric test ball for rapid detection of trivalent antimony in water, characterized in that: The specific steps include: Step 1: Solution preparation preparing a rhodamine B solution, a graphene solution, a sodium alginate solution and a sodium thioglycolate solution; Step 2: Formation of composite material solution Ultrasonic treatment of the graphene solution, after uniform dispersion, adding the graphene solution to the sodium alginate solution and mixing evenly to obtain a mixed solution of graphene and sodium alginate; then adding the sodium thioglycolate solution to the mixed solution of graphene and sodium alginate, stirring evenly to form a composite material solution; Step 3: Balling and cross-linking The composite material solution is dripped into a bath containing a calcium salt solution, and the calcium ions react with the sodium alginate in the composite material solution to form a sphere, and the sphere is soaked in the calcium salt solution, and then the sphere is taken out and immersed in a sodium alginate solution, and the sphere coated with sodium alginate is immersed in the calcium salt solution again to cause a cross-linking reaction to form a composite sphere; Step 4: Preparation of color test balls The obtained composite sphere is placed in a rhodamine B solution, taken out after soaking, and placed in a dryer for natural drying to obtain the color development test sphere.

2. The method for preparing a portable colorimetric test ball for rapid detection of trivalent antimony in water according to claim 1, characterized in that: In step 1, the specific preparation method of the rhodamine B solution is: dissolving 47.90 mg of rhodamine B powder in 100 mL of deionized water to prepare a rhodamine B solution.

3. The method for preparing a portable colorimetric test ball for rapid detection of trivalent antimony in water according to claim 1, characterized in that: In step 1, the specific preparation method of the graphene solution is: dissolving 1 g of graphene oxide powder in 100 mL of deionized water to obtain a graphene oxide solution, and then using ultrasonic treatment for 1.5 hours to obtain a graphene solution.

4. The method for preparing a portable colorimetric test ball for rapid detection of trivalent antimony in water according to claim 1, characterized in that: In step 1, the specific preparation method of the sodium alginate solution is: add 2 g of sodium alginate powder into 100 mL of deionized water, and stir to dissolve to obtain the sodium alginate solution.

5. The method for preparing a portable colorimetric test ball for rapid detection of trivalent antimony in water according to claim 1, characterized in that: In step 1, the specific preparation method of the sodium thioglycolate solution is: dissolving 3 g of sodium thioglycolate powder in 100 mL of deionized water to prepare the sodium thioglycolate solution.

6. The method for preparing a portable colorimetric test ball for rapid detection of trivalent antimony in water according to claim 1, characterized in that: In step 3, the calcium salt solution is a calcium chloride solution.

7. The method for preparing a portable colorimetric test ball for rapid detection of trivalent antimony in water according to claim 6, characterized in that: The specific preparation method of the calcium chloride solution is as follows: 1.665 g of calcium chloride powder is dissolved in 100 mL of deionized water to prepare the calcium chloride solution.

8. The method for preparing a portable colorimetric test ball for rapid detection of trivalent antimony in water according to claim 1, characterized in that: In step 4, the soaking time is 2 hours and the drying temperature is less than 50°C.

9. A portable colorimetric test ball for rapid detection of trivalent antimony in water, characterized in that: The color developing test ball is prepared by the preparation method according to any one of claims 1 to 8.

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