Ion-selective membrane, composite liquid perchlorate ion-selective electrode and application

Abstract

The application discloses an ion-selective membrane, a composite liquid perchlorate ion-selective electrode and application, and belongs to the technical field of ion-selective electrodes. The ion-selective membrane is prepared from raw materials including an ion carrier, an ion exchanger, a plasticizer and a membrane matrix; wherein the ion carrier includes one, two or more than two of m-tetraphenylporphyrin ferric chloride, tetra-p-chlorophenylporphyrin iron and m-tetra(pentafluorophenyl)porphyrin ferric chloride, and the ion-selective membrane is selective to ClO4 ‑ has better selectivity.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of ion selective electrode, more particularly to an ion selective membrane, a composite liquid perchlorate ion selective electrode and application. BACKGROUND

[0002] Perchlorate (ClO4 - ) is a common inorganic pollutant, mainly from the production and use of fireworks, aerospace propellants, military products, textile fixatives and battery products. Because of its high solubility and mobility, and difficult to degrade in the environment, it is easy to diffuse and migrate in surface water and groundwater.

[0003] At present, the detection methods of perchlorate mainly include complex colorimetric method, ion chromatography, liquid chromatography-mass spectrometry and ion selective electrode method (ISE). Among them, ion selective electrode method is particularly suitable for online monitoring due to its low detection cost, simple operation and wide linear range. The traditional liquid ion selective electrode usually needs to be connected with a reference electrode, while the new type of composite liquid perchlorate ion selective electrode does not need to be connected with a reference electrode, realizes the integration of reference electrode and working electrode, and the external reference chamber does not contain silver ions, has strong anti-pollution ability, and further improves its stability and application potential in complex environment. SUMMARY

[0004] 1. Technical problems to be solved by the application

[0005] In view of the problems of poor selectivity and anti-interference of the perchlorate ion selective electrode in the prior art when detecting ClO4 - , an ion selective membrane is provided, and a composite liquid perchlorate ion selective electrode is also provided.

[0006] 2. Technical solutions

[0007] In order to achieve the above purpose, the technical solutions provided by the present application are as follows:

[0008] The ion selective membrane provided by the present application comprises an ion carrier, an ion exchanger and a membrane base.

[0009] The ion carrier comprises one, two or more of m-tetraphenylporphyrin iron chloride, tetra-p-chlorophenylporphyrin iron and m-tetra(pentafluorophenyl)porphyrin iron chloride.

[0010] Further, the ion selective membrane further comprises a plasticizer and a membrane base.

[0011] The composite liquid perchlorate ion selective electrode provided by the present application comprises an ion selective membrane and a working electrode.

[0012] The mass ratio of the film base, plasticizer, ion carrier and ion exchanger is (30-50):(45-69):(0.5-2.5):(0.5-2.5).

[0013] Further, the ion exchanger comprises one, two or more of dodecylmethylammonium chloride, hexadecyltrimethylammonium bromide and trioctylmethylammonium chloride.

[0014] Further, the plasticizer comprises one, two or more of o-nitrophenyl octyl ether, dibutyl phthalate and dioctyl phthalate.

[0015] Further, the film base comprises polyvinyl chloride.

[0016] Preferably, the film base is polyvinyl chloride.

[0017] The application also provides a preparation method of the ion selective membrane, which comprises drying mixture A containing an ion carrier, an ion exchanger, a plasticizer and a film base to form an ion selective membrane.

[0018] Further, the solvent of mixture A is one or both of tetrahydrofuran and cyclohexanone.

[0019] Further, the preparation method of mixture A comprises adding an ion carrier, an ion exchanger, a plasticizer and a film base into a solvent and ultrasonicating for 30-60 minutes, wherein the ultrasonicating is used for degassing.

[0020] The application also provides a composite liquid perchlorate ion selective electrode,

[0021] which comprises an electrode body and an electrode tail connected in sequence.

[0022] The electrode body comprises a front end cap and an electrode body shell connected in sequence.

[0023] The electrode body shell is provided with an ion selective working electrode and a reference electrode assembly.

[0024] The ion selective working electrode comprises a front end cap, a working electrode tube and a working electrode tail plug connected in sequence.

[0025] The ion selective membrane is arranged between the front end cap and the working electrode tube.

[0026] The reference electrode assembly comprises a second porous material part, a reference electrode tube and a reference electrode tail plug connected in sequence.

[0027] Further, one end of the working electrode tube protrudes from the front end cap,

[0028] The working electrode tube body is provided with a plurality of through holes at the end connected with the front end cap.

[0029] Further, the ion selective working electrode is filled with 10 -4 ~ 10 -2 M perchlorate ion solution;

[0030] The electrode body is filled with (NH4)2SO4 solution;

[0031] The reference electrode assembly is filled with saturated KCl solution.

[0032] For example, the electrode body is filled with (NH4)2SO4 solution with a concentration of 0.1M.

[0033] Further, the concentration of perchlorate ions in the perchlorate ion solution is 10 -2 M.

[0034] Preferably, the saturated KCl solution is a gel type saturated KCl solution.

[0035] Further, the perchlorate ions are from one, two or more of NaClO4, KClO4 and Mg(ClO4)2.

[0036] For example, the perchlorate ions are from NaClO4.

[0037] Further, the ion selective working electrode further comprises a first reference electrode, which is threaded through the working electrode tail plug.

[0038] Further, the reference electrode assembly further comprises a second reference electrode, which is threaded through the reference electrode tail plug.

[0039] Further, the front end cap is provided with a first porous material component.

[0040] Further, the first porous material component is a ceramic filter element;

[0041] The second porous material component is a ceramic filter element.

[0042] The ceramic filter element can be a porous ceramic filter element.

[0043] Further, the working electrode tube body comprises a first connecting tube body and a second connecting tube body connected in sequence;

[0044] The first connecting tube body is inserted into the front end cap, one end of the first connecting tube body is connected with the ion selective membrane, and the front end cap is sleeved on the first connecting tube body.

[0045] Further, the first porous material component is arranged on a fixing member.

[0046] Further, the electrode body further comprises a fixing cover plate.

[0047] The fixing cover plate is connected with the electrode body shell.

[0048] Further, the fixing cover plate is provided with a through hole for fixing the ion selective working electrode and the reference electrode assembly.

[0049] Further, the electrode tail end is provided with a circuit mainboard.

[0050] The circuit mainboard comprises a single-chip microcomputer chip and auxiliary circuits thereof, a power management circuit, an RS485 communication circuit and an ion selective electrode signal operational amplifier circuit.

[0051] Further, the first reference electrode and the second reference electrode are connected with the circuit mainboard.

[0052] The application further provides application of the ion selective membrane or the composite liquid perchlorate ion selective electrode in detection of ClO4 - in detection of ClO4 - .

[0053] 3. Beneficial effects

[0054] Compared with the prior art, the technical scheme provided by the application has the following beneficial effects:

[0055] (1) The ion selective membrane provided by the application comprises an ion carrier, an ion exchanger, a plasticizer and a membrane matrix; wherein the ion carrier comprises one, two or two or more of m-tetraphenylporphyrin iron chloride, tetra-p-chlorophenylporphyrin iron, m-tetra(pentafluorophenyl)porphyrin iron chloride, and when the ion carrier is used, the ion selective membrane has better selectivity for ClO4 - .

[0056] (2) The composite liquid perchlorate ion selective electrode provided by the application comprises a built-in double-salt bridge reference electrode assembly, utilizes the internal cavity of the electrode body shell as an external salt bridge part, can increase the electrolyte storage capacity, provides a more stable reference potential and a longer electrode service life; not only overcomes the defects of the traditional liquid ion selective electrode, significantly improves the performance and service life of the electrode, but also provides a more reliable and more accurate detection tool for water quality monitoring, and has a broad application prospect. BRIEF DESCRIPTION OF DRAWINGS

[0057] Figure 1 FIG. 1 is a structure schematic view of a composite liquid perchlorate ion selective electrode in Embodiment 1 of the application.

[0058] Figure 2 Figure 1 is a partial exploded view of a composite liquid perchlorate ion selective electrode according to an embodiment of the present application.

[0059] Figure 3 Figure 2 is a general exploded view of an electrode body according to an embodiment of the present application.

[0060] Figure 4 Figure 3 is a partial exploded view of an electrode body according to an embodiment of the present application.

[0061] Figure 5 Figure 4 is a cross-sectional view of a connection structure of a front end cap, a first connecting pipe body and a front end end cap according to an embodiment of the present application. Figure 4

[0062] Figure 6 Figure 5 is a partial enlarged view of a connection structure of a front end cap and a first connecting pipe body according to an embodiment of the present application. Figure 5

[0063] Figure 7 Figure 6 is a standard curve diagram of ClO4 - , NO3 - , CO3 2- , PO4 3- , Cl - , SO4 2- of a liquid perchlorate ion selective electrode according to an application example 1 of the present application.

[0064] Figure 8 Figure 7 is a standard curve diagram of ClO4 - , NO3 - , CO3 2- , PO4 3- , Cl - , SO4 2- of a liquid perchlorate ion selective electrode according to an application example 2 of the present application.

[0065] Figure 9 Figure 8 is a standard curve diagram of ClO4 - , NO3 - , CO3 2- , PO4 3- , Cl - , SO4 2- of a liquid perchlorate ion selective electrode according to an application example 3 of the present application.

[0066] Explanation of reference numerals in the drawings:

[0067] 100, electrode body;

[0068] 110, electrode body shell; 111, first porous material part;

[0069] ​​120, ion-selective working electrode; 121, front end cap; 122, working electrode tube; 1221, first connecting tube; 1222, second connecting tube; 123, working electrode tail plug; 124, first reference electrode; 125, ion-selective membrane;

[0070] 130, reference electrode assembly; 131, second porous material component; 132, reference electrode tube; 133, reference electrode tail plug; 134, second reference electrode;

[0071] 140, fixed cover plate;

[0072] 150, front end cap; 151, fixing member; 152, snap ring; 153, connecting ring body; 154, clamping groove;

[0073] 200, electrode tail end; 210, circuit mainboard. DETAILED DESCRIPTION

[0074] The present disclosure can be more easily understood by reference to the following description in conjunction with the examples included herein. It should be understood that the present disclosure is not limited to the particular products, methods, conditions or parameters described and / or shown herein, and / or all the functions let alone combinations thereof. Furthermore, the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting, unless otherwise specified.

[0075] It should also be understood that, for clarity, certain features of the disclosure can be described in the context of separate embodiments, but can also be provided in combination in a single embodiment. That is, unless explicitly stated otherwise, each separate embodiment is considered to be combinable with any other embodiment, and such combinations are considered to represent a different embodiment. Conversely, various features of the disclosure described in the context of a single embodiment can also be provided separately or in any sub-combination, for the sake of brevity. Finally, while a particular embodiment can be described as part of a series of steps or part of a more general structure, each step or sub-structure can itself be considered an independent embodiment.

[0076] Unless otherwise stated, it is to be understood that each individual element in a list and each combination of individual elements in the list is to be interpreted as a different embodiment. For example, a list of embodiments recited as“A, B, or C” is to be interpreted as including the embodiments“A,”“B,”“C,”“A or B,”“A or C,”“B or C,” or“A, B, or C.”

[0077] In this disclosure, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to "a substance" is a reference to at least one of such a substance and equivalents thereof.

[0078] When describing items by using the conjunctive term "and / or," and the like, the description shall be understood as including any one of the associated listed items, as well as all combinations of one or more of them.

[0079] Generally, the use of the term "about" indicates an approximation that can vary depending on the desired characteristics of the subject matter disclosed by the use of the term "about," and will be interpreted based on functionality in a context-dependent manner. Thus, a person of ordinary skill in the art will be able to interpret a degree of variance on a case-by-case basis. In some cases, the number of significant digits used in expressing a particular value can be representative of the degree of precision to which the term "about" allows for variation. In other cases, a range of values can be determined using a progression of values between a lower limit and an upper limit, the range of values being determined by the term "about." Further, all ranges in the present disclosure are inclusive and combinable, and a reference to a value in a range includes each value in the range.

[0080] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs; the terminology used herein and / or any and all combinations of one or more related items listed.

[0081] The following examples were carried out under ordinary conditions or under conditions recommended by the manufacturer unless otherwise specified. The reagents or instruments used were all conventional products available on the market unless otherwise specified.

[0082] The present application is further illustrated in the following specific examples, but the examples do not limit the present application in any form. Unless otherwise specified, the reagents, methods and equipment used in the present application are conventional reagents, methods and equipment in the art. The essential features and significant effects of the present application can be embodied in the examples described below, and the described examples are part of the examples of the present application, but not all examples. Therefore, they do not limit the present application in any way, and those skilled in the art can make some non-essential improvements and adjustments according to the content of the present application, which are all within the scope of protection of the present application.

[0083] The ion selective membrane 126 in the present application is prepared from the following raw materials: an ion carrier, an ion exchanger, a plasticizer, and a membrane matrix; wherein the ion carrier includes one, two, or more than two of m-tetraphenylporphyrin iron chloride, tetra-p-chlorophenylporphyrin iron, and m-tetra(pentafluorophenyl)porphyrin iron chloride; the ion exchanger includes one, two, or more than two of dodecylmethylammonium chloride, hexadecyltrimethylammonium bromide, and trioctylmethylammonium chloride; the plasticizer includes one, two, or more than two of o-nitrophenyl octyl ether, dibutyl phthalate, and dioctyl phthalate; and the membrane matrix includes polyvinyl chloride. As a preferred embodiment, the membrane matrix is polyvinyl chloride.

[0084] Further, the mass ratio of the membrane matrix, the plasticizer, the ion carrier, and the ion exchanger is (30-50):(45-69):(0.5-2.5):(0.5-2.5).

[0085] The preparation method of the ion selective membrane 126 is as follows: drying the mixture A containing the ion carrier, the ion exchanger, the plasticizer, and the membrane matrix to form the ion selective membrane 126. As a specific embodiment, the mixture A containing the ion carrier, the ion exchanger, the plasticizer, and the membrane matrix can be poured into a glass culture dish and then placed in an oven for drying.

[0086] Further, the preparation method of the mixture A is as follows: adding the ion carrier, the ion exchanger, the plasticizer, and the membrane matrix into a solvent and ultrasonicating for 30-60 minutes for degassing; and the solvent of the mixture A is one or both of tetrahydrofuran and cyclohexanone. As a specific embodiment, the solvent of the mixture A can be tetrahydrofuran, which can be removed by drying after being used as a solvent, and the specific amount of use can be adjusted to facilitate the dissolution of the raw materials and drying removal.

[0087] Example 1

[0088] In combination Figures 1-4 The composite liquid perchlorate ion selective electrode of the present embodiment includes an electrode main body 100 and an electrode tail end 200 connected in sequence; the electrode main body 100 includes a front end cap 150 and an electrode main body shell 110 connected in sequence, and the electrode main body shell 110 is provided with an ion selective working electrode 120 and a reference electrode assembly 130;

[0089] The ion selective working electrode 120 comprises a front end cap 121, a working electrode tube 122 and a working electrode tail plug 123 connected in sequence; the working electrode tube 122 protrudes from the front end cap 150 at one end, and the ion selective membrane 125 is arranged between the front end cap 121 and the working electrode tube 122; the working electrode tube 122 is provided with a plurality of through holes at one end connected with the front end cap 121; the reference electrode assembly 130 comprises a second porous material component 131, a reference electrode tube 132 and a reference electrode tail plug 133 connected in sequence, and the reference electrode assembly 130 is located in the electrode main body shell 110 and does not protrude from the front end cap 150 at one end. The composite liquid high-chlorate ion selective electrode with a built-in double-salt bridge reference electrode assembly 130 uses the cavity inside the electrode main body shell 110 as an external salt bridge part, which can increase the electrolyte storage capacity, provide a more stable reference potential and a longer electrode service life; not only overcomes the defects of traditional liquid ion selective electrodes, significantly improves the performance and service life of the electrode, but also provides a more reliable and accurate detection tool for water quality monitoring, and has a broad application prospect.

[0090] As a specific embodiment, the working electrode tube 122 can be a circular tube, which can be made of polyvinyl chloride plastic material or glass material. The second porous material component 131 in the reference electrode assembly 130 can be a ceramic filter element, which can be in the shape of a cylinder; the reference electrode tube 132 can be a circular tube made of polyvinyl chloride plastic material or glass material; and the ceramic filter element can be inserted into the reference electrode tube 132. The size and shape of the working electrode tail plug 123 and the reference electrode tail plug 133 can be determined according to the connected pipe diameter.

[0091] The end of the working electrode tube 122 protruding from the front end cap 150 is provided with a ring-shaped small hole, and the ion selective membrane 125 is bonded and covered thereon. As a specific embodiment, UV glue is coated around the ion selective membrane 125 and cured by ultraviolet light, so that the ion selective membrane 125 is tightly bonded on the working electrode tube 122, and then the ion selective membrane 125 is fixed by the front end cap 121. On the other hand, ion selective membranes 125 of appropriate size can be obtained by drying, for example, using a puncher to obtain ion selective membranes 125 of appropriate size, and then putting them into the ion selective working electrode 120.

[0092] Further, the working electrode tube 122 in the ion selective working electrode 120 is filled with perchlorate ion solution; the reference electrode tube 132 in the reference electrode assembly 130 is filled with saturated KCl solution; the electrode body shell 110 in the electrode body 100 is filled with (NH4)2SO4 solution. As an optional embodiment, the perchlorate ion is from one, two or more of NaClO4, KClO4, Mg(ClO4)2. For example, the perchlorate ion is from NaClO4. The saturated KCl solution is a gel type saturated KCl solution. The working electrode tail plug 123 is connected with the working electrode tube 122, which can prevent the perchlorate ion solution from leaking from the end of the working electrode tube 122; the reference electrode tube 132 is connected with the reference electrode tail plug 133, which can prevent the saturated KCl solution from leaking from the end of the reference electrode tube 132.

[0093] Further, the ion selective working electrode 120 further comprises a first reference electrode 124, which is threaded through the working electrode tail plug 123. After the first reference electrode 124 is led out through the working electrode tail plug 123, the rear end of the working electrode tube 122, including the connection between the working electrode tail plug 123 and the working electrode tube 122 and the connection between the first reference electrode 124 and the working electrode tail, is sealed by a glue such as silicone or epoxy resin glue, so as to improve the sealing of the ion selective working electrode 120. The reference electrode assembly 130 further comprises a second reference electrode 134, which is threaded through the reference electrode tail plug 133. After the second reference electrode 134 is led out through the reference electrode tail plug 133, the rear end of the reference electrode tube 132, including the connection between the reference electrode tail plug 133 and the reference electrode tube 132 and the connection between the first reference electrode 124 and the tail of the reference electrode assembly 130, is sealed by a glue such as silicone or epoxy resin glue, so as to improve the sealing of the reference electrode assembly 130. As a specific embodiment, the first reference electrode 124 and the second reference electrode 134 are both Ag / AgCl electrode wires, and the Ag / AgCl electrode wire is specifically a silver chloride electroplated silver wire. The working electrode tail plug 123 and the reference electrode tail plug 133 can be provided with wire holes for threading the Ag / AgCl electrode wire, and the connection between the wire hole and the Ag / AgCl electrode wire is also sealed by silicone or epoxy resin glue.

[0094] Further, the first porous material component 111 is arranged on the front end cap 150. As an optional embodiment, the first porous material component 111 is a ceramic filter element, which can be in the shape of a cylinder. The (NH4)2SO4 solution filled in the electrode body shell 110 can be leaked into the environment water body through the ceramic filter element.

[0095] In combination Figure 4As an optional embodiment, the working electrode tube 122 comprises a first connecting tube 1221 and a second connecting tube 1222 connected in sequence; the first connecting tube 1221 is inserted into the front end cap 150, and the second connecting tube 1222 can be detachably connected with the first connecting tube 1221 by thread connection or clamping groove connection. One end of the first connecting tube 1221 is connected with the ion selective membrane 125, and the front end cap 121 is sleeved on the first connecting tube 1221 to further fix the ion selective membrane 125. The first connecting tube 1221 is detachably connected, which facilitates the disassembly and installation of the ion selective membrane 125.

[0096] In combination Figure 5 、 Figure 6 As an optional embodiment, the front end cap 150 comprises a fixing piece 151, a clamping ring 152 and a connecting ring 153. The first connecting tube 1221 is inserted into the fixing piece 151; the clamping ring 152 and the connecting ring 153 are arranged on the same side of the fixing piece 151. The first connecting tube 1221, the fixing piece 151, the clamping ring 152 and the connecting ring 153 can be an integrated structure to improve the sealing performance.

[0097] The first connecting tube 1221 can be a round tube with one end closed. The end face of the closed end, i.e. the place where the film is attached, is provided with an annularly arranged through hole, on which the ion selective membrane 125 can be bonded and covered. The size of the ion selective membrane 125 can be the same as that of the end face; the other end cooperates with the clamping ring 152 to form a clamping groove 154 and is connected with the second connecting tube 1222 by clamping groove connection. The fixing piece 151 is a circular fixing plate, and the first connecting tube 1221 protrudes from the fixing piece 151 so that the ion selective membrane 125 protrudes out of the fixing piece 151. The connecting ring 153 is provided with protrusions and grooves on the outer periphery, which can be detachably connected with the electrode main body shell 110 by clamping, and can also be disassembled to facilitate the installation of the ion selective membrane 125. The first porous material part 111 is inserted into the fixing piece 151. On the other hand, the clamping ring 152 and the first porous material part 111 are arranged in the area surrounded by the connecting ring 153.

[0098] The front end cap 121 is sleeved on the first connecting tube 1221 to further fix the ion selective membrane 125. The end of the front end cap 121 in contact with the ion selective membrane 125 is provided with a through hole to facilitate the normal contact and detection of the ion selective membrane 125.

[0099] Further, the electrode main body 100 further comprises a fixed cover plate 140, which is connected with the electrode main body shell 110. For example, the outer edge of the fixed cover plate 140 can be provided with threads to be connected with the electrode main body shell 110, or a connecting ring body 153 provided with a protrusion and a groove around the periphery can be used to be connected with the electrode main body shell 110. After the front end cap 150 and the fixed cover plate 140 are connected with the electrode main body shell 110, a closed cavity is formed, and the (NH4)2SO4 solution can be filled in the electrode main body shell 110. As a specific embodiment, the fixed part 151 in the front end cap 150, the fixed cover plate 140 and the electrode main body shell 110 form a closed cavity after being connected.

[0100] The fixed cover plate 140 is provided with through holes for fixing the ion selective working electrode 120 and the reference electrode assembly 130. As an optional embodiment, two through holes can be provided on the fixed cover plate 140, which have the same outer diameter as the working electrode tube body 122 and the reference electrode tube body 132 respectively, so as to fix the ion selective working electrode 120 and the reference electrode assembly 130. As another optional embodiment, the two through holes on the fixed cover plate 140 can be communicated to further reduce the volume.

[0101] Further, the electrode tail end 200 is provided with a circuit main board 210; the circuit main board 210 comprises a single-chip microcomputer chip and its auxiliary circuit, a power management circuit, an RS485 communication circuit and an ion selective electrode signal amplification circuit. The ion selective electrode signal amplification circuit is used to collect, transmit and amplify the signal generated by the ion selective working electrode 120. The first reference electrode 124 and the second reference electrode 134 are connected with the circuit main board 210. Specifically, the first reference electrode 124 and the second reference electrode 134 can be welded to the circuit main board 210.

[0102] Application Example 1

[0103] Preparation of ion selective membrane 125: 176.4 mg of polyvinyl chloride, 176.4 mg of o-nitrophenyl octyl ether, 3.6 mg of m-tetraphenylporphyrin iron (III) chloride (purchased from Aldrich, CAS No.: 16456-81-8) and 3.6 mg of chlorinated dodecylmethylammonium were dissolved in 2.5 mL of tetrahydrofuran solvent, ultrasonic degassing for 30 minutes, the mixed solution was poured into a glass culture dish with a diameter of 4 cm, and then placed in a 40°C oven for drying to form an ion selective membrane 125 with a thickness of about 0.2 mm; using the liquid perchlorate ion selective electrode in Example 1, a puncher was used to take an ion selective membrane 125 with a diameter of 8 mm, which was bonded to the first connecting tube body 1221. Specifically, UV glue was coated around the ion selective membrane 125 and cured by ultraviolet light, so that the ion selective membrane 125 was tightly bonded to the membrane bonding part of the first connecting tube body 1221, and then the ion selective membrane 125 was fixed with the front end cap 121; wherein the working electrode tube 122 of the ion selective working electrode 120 was filled with a NaClO4 solution with a concentration of 10 -2 mol / L, the electrode main body shell 110 was filled with a (NH4)2SO4 solution with a concentration of 0.1 mol / L, and the reference electrode assembly 130 was filled with a gel type saturated KCl solution; the type of ion selective electrode signal operational amplifier circuit chip is LM358 (purchased from: https: / / item.taobao.com / item.htm?_u=q2osq1scb7c7&id=562928076498&spm=a1z09.2.0.0.589d2e8dO0Rj5x).

[0104] Application Example 2

[0105] The basic process is the same as that of Application Example 1, except that the ion carrier in the raw material of the ion selective membrane 126 of the liquid perchlorate ion selective electrode of this application example is tetra-p-chlorophenyl porphyrin iron (III) (purchased from Aldrich, CAS No.: 36965-70-5).

[0106] Application Example 3

[0107] The basic process is the same as that of Application Example 1, except that the ion carrier in the raw material of the ion selective membrane 126 of the liquid perchlorate ion selective electrode of this application example is m-tetra(pentafluorophenyl)porphyrin iron (III) chloride (purchased from Merck, CAS No.: 36965-71-6).

[0108] Performance test

[0109] The composite liquid perchlorate ion selective electrode prepared in the above application examples was placed in a 10 -8 mol / L and 10 -3 mol / L ClO4- The solution was activated for 12 hours, and then 10 -5 mol / L, 10 -4 mol / L, 10 -3 mol / L, 10 -2 mol / L, 10 -1 mol / L of ClO4 - Gradient solution, the composite liquid perchlorate ion selective electrode was directly connected with a potentiometer, and the potential value under the ClO4 - concentration gradient solution was recorded by the potentiometer, and then the standard curve was drawn according to the ClO4 - concentration logarithmic value and the potential value. The selectivity of the liquid perchlorate ion selective electrode was tested by the separate solution method. The potential standard curves of the main response ion i (ClO4 - ) and the interfering ions j (NO3 - , CO3 2- , PO4 3- , Cl - , SO4 2- ) were determined, wherein the potential standard curves of the interfering ions j (NO3 - , CO3 2- , PO4 3- , Cl - , SO4 2- ) were determined by each ion alone, and each ion was configured with 10 -5 mol / L, 10 -4 mol / L, 10 -3 mol / L, 10 -2 mol / L, 10 -1 mol / L gradient solution, and the potential values of the main response ion i and the other common ions j with the concentration of 1M were extrapolated by the standard curve and other common ions j According to the formula (in the formula: Z i is the charge number of the main response ion i, F is the Faraday constant, R is the ideal gas constant, and T is the temperature) to calculate lgK ij The specific results are shown in Table 1.

[0110] Table 1: The lgK data of the liquid perchlorate ion selective electrode prepared in different application examples ij

[0111]

[0112] As can be seen from Table 1, the interference degree of the interfering ions on the electrode detection of ClO4 - is in the order from strong to weak: NO3 - > CO3​2- >PO4 3- >Cl - >SO4 2- , SO4 2- NO3 - The interference to the electrode is the strongest. The application example selection and anti-interference ranking: application example 3>application example 1>application example 2.

Claims

1. A perchlorate ion-selective membrane, characterized in that: It contains ion carriers and ion exchangers; The ion support includes one, two or more of the following: m-tetraphenylporphyrin ferric chloride, tetrachlorophenylporphyrin ferric chloride, and m-tetra(pentafluorophenyl)porphyrin ferric chloride; It also contains plasticizers and film matrix; The mass ratio of the membrane matrix, plasticizer, ion carrier, and ion exchanger is (30~50):(45~69):(0.5~2.5):(0.5~2.5). The ion exchanger comprises one, two, or more of tris(dodecylmethylammonium chloride), hexadecyltrimethylammonium bromide, and trioctylmethylammonium chloride; and / or, The plasticizer includes one, two, or more of o-nitrophenyl octyl ether, dibutyl phthalate, and dioctyl phthalate; and / or The membrane substrate includes polyvinyl chloride.

2. A composite liquid perchlorate ion selective electrode, characterized in that: It includes an electrode body (100) and an electrode tail end (200) connected in sequence. The electrode body (100) includes a front end cap (150) and an electrode body shell (110) connected in sequence. The electrode body shell (110) is provided with an ion-selective working electrode (120) and a reference electrode assembly (130). The ion-selective working electrode (120) includes a front cap (121), a working electrode tube (122), and a working electrode tail plug (123) connected in sequence. A perchlorate ion selective membrane (125) as described in claim 1 is disposed between the front cap (121) and the working electrode tube (122). The reference electrode assembly (130) includes a second porous material component (131), a reference electrode tube (132), and a tail plug of the reference electrode assembly (130) connected in sequence.

3. The composite liquid perchlorate ion selective electrode according to claim 2, characterized in that: The ion-selective working electrode (120) is filled with a perchlorate ion solution; The electrode body (100) is filled with (NH4)2SO4 solution; The reference electrode assembly (130) is filled with a saturated KCl solution.

4. The composite liquid perchlorate ion selective electrode according to claim 3, characterized in that: The ion-selective working electrode (120) further includes a first reference electrode (124), which is disposed in the end cap (123) of the working electrode. The reference electrode assembly (130) further includes a second reference electrode (134), which is disposed at the tail end plug of the reference electrode assembly (130); The front end cap (150) is provided with a first porous material component (111).

5. The composite liquid perchlorate ion selective electrode according to claim 4, characterized in that: The working electrode tube (122) includes a first connecting tube (1221) and a second connecting tube (1222) connected in sequence. The first connecting tube (1221) is inserted into the front end cap (150), one end of the first connecting tube (1221) is connected to the ion-selective membrane (125), and the front end cap (121) is sleeved on the first connecting tube (1221).

6. The composite liquid perchlorate ion selective electrode according to any one of claims 2 to 5, characterized in that: The electrode body (100) also includes a fixing cover plate (140); The fixed cover plate (140) is connected to the electrode body shell (110); The fixed cover plate (140) is provided with through holes for fixing the ion-selective working electrode (120) and the reference electrode assembly (130).

7. The composite liquid perchlorate ion selective electrode according to claim 6, characterized in that: A circuit board (210) is provided inside the electrode tail end (200); The first reference electrode (124) and the second reference electrode (134) are connected to the circuit board (210).

8. A perchlorate ion-selective membrane as described in claim 1 or a composite liquid perchlorate ion-selective electrode as described in any one of claims 2 to 7 for detecting ClO4 - Applications in [the context of the text].

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