Device and method for automatic separation and reversible elution of TIMS sample isotopes

Abstract

The invention relates to the technical field of isotope analysis and testing in geological rocks, and specifically discloses a device and method for automatic separation and reversible elution of TIMS sample isotopes, comprising a rotary elution mechanism and a reverse elution mechanism, wherein the rotary elution mechanism is provided with a burette and a rotary frame, the rotary frame is connected to an elution motor through a rotary column, a plurality of elution reagent bottles are evenly mounted on the rotary frame, a burette is mounted at the lower part of the elution reagent bottle, a chromatography column is arranged below the burette, and a sample receiving bottle is placed below the chromatography column; a three-part structure formed by a liquid receiving funnel, a resin layer column and a dripping head is a split structure; a finger cylinder clamps the resin layer column in the middle of the chromatography column, the rear part of the finger cylinder is connected to a motor shaft of a reverse elution motor, and the reverse elution motor drives the finger cylinder and the resin layer column to rotate for reverse elution; the invention reduces labor intensity and improves the accuracy and stability of experimental data; reverse elution reduces elution volume and improves element enrichment efficiency.

Description

Technical Field

[0001] The invention relates to the technical field of isotope analysis and testing in geological rocks, and in particular to a device and method for automatic separation of isotopes of a thermal ionization mass spectrometer (TIMS) ion source sample and reversible elution under a natural flow state. Background Art

[0002] Rock samples contain a variety of metal elements such as Ba, Sr, Ca, Mg, Rb, K, Na, Li, and Nd. The isotope ratios of certain metal elements (87Sr / 86Sr, 143Nd / 144Nd, 87Rb / 86Sr, and 147Sm / 144Nd) play a very important role in determining the age of carbonate rocks and silicate rocks, as well as tracing the genesis of rocks and the geological processes of diagenesis and superposition. Before using a thermal ionization mass spectrometer (TIMS) to determine the isotope ratios of metal elements, the metal elements must be separated, enriched, and purified from geological samples with complex components to remove the interference of isotopes and reduce the influence of matrix elements. This process usually requires the use of multiple liquid addition columns equipped with ion exchange resins. A certain concentration and volume of hydrochloric acid solution (or nitric acid solution and other acid solutions) is added to the resin column (chromatographic column) to separate the target isotope from other isotopes, matrix elements, and trace elements. The entire addition process requires manual operation and recording. Because hydrochloric acid solution or other acid solution of different concentrations and dosages needs to be added at different time periods, there are relatively strict requirements on the flow rate and flow rate of the solution. The entire sample and liquid addition process is complicated (resin column regeneration, balance, sample addition, elution, collection of target elements, further elution, and water washing to neutrality), which is time-consuming and wastes manpower. In addition, fatigue and mistakes are prone to occur during manual operation, which reduces experimental efficiency and thus reduces the accuracy and stability of experimental data.

[0003] The existing methods of adding acid reagents to the chromatography column all adopt forward addition elution. When the isotope distribution coefficients to be collected are very different, a large volume of eluent is required, and the element enrichment efficiency is low. Therefore, it is urgent to design a simple, practical, and inexpensive device and method for automatic separation of sample isotopes in a thermal ionization mass spectrometer (TIMS) ion source that can be reversely eluted under a natural flow state, so as to solve the problem that the existing rock sample elution and purification of elements cannot be reversely eluted and the efficiency is low. Summary of the invention

[0004] In view of the problems existing in the prior art, the object of the present invention is to provide a device and method for automatic separation and reversible elution of TIMS sample isotopes.

[0005] The technical solution adopted by the present invention to solve the technical problem is: a TIMS sample isotope automatic separation and reversible elution device comprises a rotating elution mechanism and a reverse elution mechanism, the rotating elution mechanism is provided with a burette and a rotating frame, the rotating frame adopts a disc-shaped structure, the rotating frame is connected to the elution motor through a rotating column, the elution motor controls the rotating frame to rotate at a fixed angle, a plurality of elution reagent bottles are evenly installed on the rotating frame, a burette is installed at the lower part of the elution reagent bottle, a chromatography column is arranged below the burette, and a sample receiving bottle is placed below the chromatography column;

[0006] The chromatography column comprises a liquid receiving funnel at the top, a resin layer column at the middle and a liquid dropping head at the bottom. The three-part structure formed by the liquid receiving funnel, the resin layer column and the liquid dropping head is a split structure.

[0007] The reverse elution mechanism is provided with a finger cylinder and a reverse elution motor. The finger cylinder clamps the resin layer column in the middle of the chromatography column. The rear of the finger cylinder is connected to the motor shaft of the reverse elution motor. The reverse elution motor drives the finger cylinder and the resin layer column to rotate for reverse elution.

[0008] Specifically, the chromatography column is made of polytetrafluoroethylene or high-purity quartz material, and the liquid receiving funnel on the upper part of the chromatography column receives the reagent dripping from the elution reagent bottle; the resin layer column in the middle of the chromatography column is placed with upper and lower sieve plates, and a resin layer is arranged between the two sieve plates, and the resin layer is encapsulated with ion exchange resin.

[0009] Specifically, a funnel joint is installed at the bottom of the liquid receiving funnel, small horn joints are installed at both ends of the resin layer column, and a large horn joint is installed on the top of the drip head. The funnel joint, the small horn joint and the large horn joint are all made of soft rubber material. The funnel joint is inserted into the small horn joint, and the small horn joint at the bottom is inserted into the large horn joint. After the resin layer column is rotated back to its position, the liquid receiving funnel, the resin layer column and the drip head automatically form an internal through channel.

[0010] Specifically, the elution reagent bottles are provided with 8 groups, including two groups of elution reagent bottles one, two groups of elution reagent bottles two, two groups of elution reagent bottles three and two groups of elution reagent bottles four. The angles between two adjacent elution reagent bottles and the center of the rotating frame are both 45°. The elution reagent bottle one contains 2.5 mol / L hydrochloric acid reagent, the elution reagent bottle two contains 5.0 mol / L hydrochloric acid reagent, the elution reagent bottle three contains 6.0 mol / L hydrochloric acid reagent, and the elution reagent bottle four contains 18.2 MΩ / cm ultrapure water.

[0011] Specifically, the bottom of the elution reagent bottle is connected to a burette through a liquid pipeline, and a solenoid valve is installed on the liquid pipeline.

[0012] Specifically, the middle part of the rotating frame is fixedly connected to a rotating column, the rotating column is rotatably mounted on a workbench through a bearing, the workbench is arranged on an electric control box, a rinsing motor is installed in the electric control box, the motor shaft of the rinsing motor is connected to the bottom of the rotating column, and an angle encoder is installed on the rinsing motor.

[0013] Specifically, 8 groups of motor brackets are installed on the workbench, a reverse elution motor is installed on the motor bracket, an angle encoder is installed on the reverse elution motor, the motor shaft of the reverse elution motor is fixedly connected to the cylinder mounting seat, a finger cylinder is installed on the other side of the cylinder mounting seat, a column clamp is installed on two finger clamps of the finger cylinder, and a buffer pad is provided on the inner side of the column clamp.

[0014] Specifically, an upper clamp bracket and a lower clamp bracket are also installed on the motor bracket, the upper clamp is installed on the upper clamp bracket, and the lower clamp is installed on the lower clamp bracket. The upper clamp and the lower clamp are both made of two butt-jointed semicircular splints, and the outer sides of the semicircular splints are fixedly connected by bolts. The upper clamp clamps the tube body at the lower part of the liquid receiving funnel, and the lower clamp clamps the tube body at the upper part of the drip head.

[0015] Specifically, a controller is installed in the electrical control box, and the controller is electrically connected to the rinsing motor, 8 groups of solenoid valves, 8 groups of reverse rinsing motors, 8 groups of finger cylinders and electric control switches. The electric control switches are installed on the workbench. The electric control switches include a power switch, a start switch, a pause switch, an emergency stop switch and 8 finger cylinder switches.

[0016] A working method of a TIMS sample isotope automatic separation and reversible elution device comprises the following steps:

[0017] S1. Place ion exchange resins and sieve plates inside 8 chromatography columns, place the resin layer columns into the column clamps one by one, control the column clamps to clamp the resin layer columns through the finger cylinder switch on the workbench, adjust the height of the receiving funnel to fix it in the upper clamp, and adjust the height of the drip head to fix it in the lower clamp;

[0018] S2. Put the corresponding hydrochloric acid solution and ultrapure water into 8 elution reagent bottles. After the treated sample solution containing the target isotope is dripped into the chromatography column funnel and dripped completely, set the dripping time of each reagent in the controller, and control the switch of the solenoid valve. The controller controls the automatic liquid addition work. First, open the solenoid valves of the two elution reagent bottles, and drip 2.5 mol / L hydrochloric acid reagent into the chromatography column through the burette. After the titration time of 2.5 mol / L hydrochloric acid reagent is over, close the solenoid valve.

[0019] S3, the controller controls the elution motor to rotate 45°, then opens the solenoid valves of the two elution reagent bottles 1 and 2, and the 2.5mol / L hydrochloric acid reagent and the 5.0mol / L hydrochloric acid reagent are dripped into the corresponding chromatography columns through the burette. After the titration of the 2.5mol / L hydrochloric acid reagent and the 5.0mol / L hydrochloric acid reagent is completed, the corresponding solenoid valves are closed respectively;

[0020] S4, after the longest titration time in the set single solenoid valve is over, the controller controls the elution motor to rotate 45° again, and then opens the solenoid valves of two elution reagent bottles one, two elution reagent bottles two and two elution reagent bottles three, and 2.5mol / L hydrochloric acid reagent, 5.0mol / L hydrochloric acid reagent and 6.0mol / L hydrochloric acid reagent are dripped into the corresponding chromatography column through the burette, and after the titration of 2.5mol / L hydrochloric acid reagent, 5.0mol / L hydrochloric acid reagent and 6.0mol / L hydrochloric acid reagent is completed, the corresponding solenoid valves are closed respectively;

[0021] S5. After the longest titration time in the set single solenoid valve is over, the controller controls the elution motor to rotate 45° again, and then opens the solenoid valves of two elution reagent bottles one, two elution reagent bottles two, two elution reagent bottles three and two elution reagent bottles four, and 2.5mol / L hydrochloric acid reagent, 5.0mol / L hydrochloric acid reagent, 6.0mol / L hydrochloric acid reagent and 18.2MΩ / cm ultrapure water are dripped into the corresponding chromatography column through the burette. After the titration of 2.5mol / L hydrochloric acid reagent, 5.0mol / L hydrochloric acid reagent, 6.0mol / L hydrochloric acid reagent and 18.2MΩ / cm ultrapure water is completed, the corresponding solenoid valves are closed respectively;

[0022] S6. Control each column to add appropriate amount of hydrochloric acid reagents of the first two concentrations for natural flow elution, and collect Rb and Sr isotope samples in the corresponding elution sections respectively;

[0023] S7. After receiving the Sr isotope sample, the reverse elution motor controls the resin layer column to rotate 180°, the funnel joint is inserted into the small trumpet joint on the upper part of the resin layer column, and the small trumpet joint on the lower part of the resin layer column is extended into the large trumpet joint. At this time, the elution reagent bottle is opened and three drops of 6.0 mol / L hydrochloric acid reagent are added to achieve natural flow reverse elution; and the rare earth element sample is received; if only Nd isotope is received, the rare earth element sample needs to be separated and purified with Ln resin, and finally the chromatography column is eluted with an appropriate amount of 6.0 mol / L hydrochloric acid reagent to regenerate it, and the column is washed with ultrapure water until it is neutral;

[0024] S8. After the elution is completed, remove the sample cup, then remove the resin layer column, and store it in a beaker filled with ultrapure water to prepare for the next elution operation.

[0025] The present invention has the following beneficial effects:

[0026] The TIMS sample isotope automatic separation and reversible elution device and method designed by the present invention adopts mechanical operation to elute the rock sample, avoiding fatigue and mistakes during manual operation, reducing labor intensity, and improving the accuracy and stability of experimental data.

[0027] The device and method for automatic separation and reversible elution of TIMS sample isotopes designed in the present invention simultaneously perform liquid addition elution through the arranged multiple stations, and the cylindrical design is convenient for experimenters to observe. The reverse elution is controlled by the reverse elution motor, thereby reducing the elution volume of elements with high distribution coefficients and improving the enrichment efficiency of the elements. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic diagram of the structure of the device for automatic separation and reversible elution of TIMS sample isotopes.

[0029] Figure 2 yes Figure 1 Enlarged view of point A in the middle.

[0030] Figure 3 This is a top view of the device for automatic isotope separation and reversible elution of TIMS samples.

[0031] Figure 4 It is a schematic diagram of the structure of a chromatography column.

[0032] Figure 5 yes Figure 4 Enlarged view of point B in the middle.

[0033] Figure 6 yes Figure 4 Enlarged view of point C in the middle.

[0034] Figure 7 It is a structural diagram of the finger cylinder.

[0035] In the figure: 1-rotating elution mechanism, 1.1-burette, 1.2-solenoid valve, 1.3-elution reagent bottle, 1.4-elution motor, 1.5-workbench, 1.6-rotating frame, 1.7-rotating column, 1.8-electric control box;

[0036] 2-reverse rinsing mechanism, 2.1-finger cylinder, 2.2-column clamp, 2.3-buffer pad, 2.4-reverse rinsing motor, 2.5-cylinder mounting seat, 2.6-motor bracket, 2.7-upper clamp, 2.8-upper clamp bracket, 2.9-lower clamp, 2.10-lower clamp bracket;

[0037] 3-chromatographic column, 3.1-resin layer, 3.2-dropping head, 3.3-liquid receiving funnel, 3.4-sieve plate, 3.5-small trumpet joint, 3.6-large trumpet joint, 3.7-funnel joint;

[0038] 4- Sample cup. DETAILED DESCRIPTION

[0039] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely further describe the technical solutions in the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0040] Embodiment 1:

[0041] like Figure 1-Figure 7 As shown, a TIMS sample isotope automatic separation and reversible elution device comprises a rotary elution mechanism 1 and a reverse elution mechanism 2. The rotary elution mechanism 1 is provided with a burette 1.1, a solenoid valve 1.2, an elution reagent bottle 1.3, a rotating frame 1.6, a workbench 1.5 and an elution motor 1.4. The rotating frame 1.6 adopts a disc-shaped structure. The rotating frame 1.6 is connected to the elution motor 1.4 through a rotating column 1.7. The elution motor 1.4 controls the rotating frame 1.3 to rotate at a fixed angle. Eight elution reagent bottles 1.3 are evenly installed on the rotating frame 1.6. The burette 1.1 is installed at the lower part of the elution reagent bottle 1.3. A chromatography column 3 is arranged below the burette 1.1, and a sample receiving bottle 4 is placed below the chromatography column 3.

[0042] The chromatography column 3 is made of polytetrafluoroethylene or high-purity quartz, with an inner diameter of 6mm and an AG50W×12 (100-200 mesh) resin bed height of 6.5cm. The chromatography column 3 includes a liquid receiving funnel 3.3 at the top, a resin layer column at the middle, and a liquid dropping head 3.2 at the bottom. The three-part structure formed by the liquid receiving funnel 3.3, the resin layer column, and the liquid dropping head 3.2 is a split structure; the liquid receiving funnel 3.3 receives the reagent dripped from the elution reagent bottle 1.3. An upper and lower sieve plate 3.4 is placed in the resin layer column at the middle of the chromatography column 3, and a resin layer 3.1 is arranged between the two sieve plates 3.4, and an ion exchange resin is encapsulated in the resin layer 3.1.

[0043] A funnel joint 3.7 is installed at the bottom of the liquid receiving funnel 3.3, small trumpet joints 3.5 are installed at both ends of the resin layer column, and a large trumpet joint 3.6 is installed on the top of the drip head 3.2. The funnel joint 3.7, the small trumpet joint 3.5 and the large trumpet joint 3.6 are all made of soft rubber material. The funnel joint 3.7 has the smallest diameter and is in the shape of a downward funnel, the large trumpet joint 3.6 has the largest diameter and is in the shape of a trumpet with a large upper opening, the small trumpet joint 3.5 has a middle diameter and is in the shape of a trumpet with a large outer opening, the funnel joint 3.7 extends into the small trumpet joint 3.5, and the small trumpet joint 3.5 at the bottom extends into the large trumpet joint 3.6. After the resin layer column rotates back to its original position, the funnel joint 3.7 at the bottom of the liquid receiving funnel 3.3 and the small trumpet joint 3.5 at the top of the resin layer column make soft contact through soft rubber, so that the funnel joint 3.7 slides into the small trumpet joint 3.5, and the small trumpet joint 3.5 is wrapped around the outside of the funnel joint 3.7. Similarly, the small trumpet joint 3.5 at the bottom of the resin layer column and the large trumpet joint 3.6 of the drip head 3.2 make soft contact through soft rubber, so that the small trumpet joint 3.5 slides into the large trumpet joint 3.6, and the large trumpet joint 3.6 is wrapped around the outside of the small trumpet joint 3.5, and the liquid receiving funnel 3.3, the resin layer column and the drip head 3.2 automatically form an internal through channel.

[0044] The elution reagent bottles 1.3 are provided with 8 groups including two groups of relative elution reagent bottles 1, two groups of relative elution reagent bottles 2, two groups of relative elution reagent bottles 3 and two groups of relative elution reagent bottles 4. The angles between two adjacent elution reagent bottles and the center of the rotating frame 1.6 are both 45°. The elution reagent bottle 1 contains 2.5 mol / L hydrochloric acid reagent, the elution reagent bottle 2 contains 5.0 mol / L hydrochloric acid reagent, the elution reagent bottle 3 contains 6.0 mol / L hydrochloric acid reagent, and the elution reagent bottle 4 contains 18.2 MΩ / cm ultrapure water.

[0045] The bottom of the elution reagent bottle 1.3 is connected to the burette 1.1 through a liquid pipeline, and a solenoid valve 1.2 is installed on the liquid pipeline. The solenoid valve 1.2 controls the titration time of the reagent volume in the burette 1.1.

[0046] The middle part of the rotating frame 1.6 is fixedly connected to the rotating column 1.7, and the rotating column 1.7 is rotatably installed on the workbench 1.5 through a bearing. The workbench 1.5 is arranged on an electric control box 1.8. The elution motor 1.4 is installed in the electric control box 1.8. The motor shaft of the elution motor 1.4 is connected to the bottom of the rotating column 1.7. An angle encoder is installed on the elution motor 1.4. The angle encoder identifies the rotation angle of the elution motor 1.4 and controls the switch of the elution motor 1.4 through a controller.

[0047] The reverse elution mechanism 2 is provided with a finger cylinder 2.1, a column clamp 2.2, a buffer pad 2.3, a reverse elution motor 2.4, a cylinder mounting seat 2.5, a motor bracket 2.6, an upper clamp 2.7 and a lower clamp 2.9. The finger cylinder 2.1 is clamped in the middle of the resin layer column, and the rear part of the finger cylinder 2.1 is connected to the motor shaft of the reverse elution motor 2.4. The reverse elution motor 2.4 drives the finger cylinder 2.1 and the resin layer column to rotate for reverse elution.

[0048] Eight groups of motor brackets 2.6 are installed on the workbench 1.5, a reverse washing motor 2.4 is installed on the motor bracket 2.6, an angle encoder is installed on the reverse washing motor 2.4, the angle encoder identifies the rotation angle of the reverse washing motor 2.4 and controls the switch of the reverse washing motor 2.4 through a controller, the motor shaft of the reverse washing motor 2.4 is fixedly connected to the cylinder mounting seat 2.5, a finger cylinder 2.1 is installed on the other side of the cylinder mounting seat 2.5, a column clamp 2.2 is installed on two finger clamps of the finger cylinder 2.1, and a buffer pad 2.3 is provided on the inner side of the column clamp 2.2.

[0049] An upper clip bracket 2.8 and a lower clip bracket 2.10 are also installed on the motor bracket 2.6. An upper clip bracket 2.7 is installed on the upper clip bracket 2.8, and a lower clip bracket 2.9 is installed on the lower clip bracket 2.10. The upper clip bracket 2.7 and the lower clip bracket 2.9 are both equipped with two butt-jointed semicircular clamps. The outer sides of the semicircular clamps are fixedly connected by bolts. The upper clip bracket 2.7 clamps the tube body at the lower part of the liquid receiving funnel 3.3, and the lower clip bracket 2.9 clamps the tube body at the upper part of the drip head 3.2.

[0050] A controller is installed in the electric control box 1.8. The controller adopts a 51 single-chip microcomputer control chip with a clock module. The controller is electrically connected to the rinsing motor 1.4, 8 groups of solenoid valves 1.2, 8 groups of reverse rinsing motors 2.4, 8 groups of finger cylinders 2.1 and electric control switches. The electric control switches are installed on the workbench 1.5. The electric control switches include a power switch, a start switch, a pause switch, an emergency stop switch and 8 finger cylinder switches.

[0051] Embodiment 2: Working principle of the device for automatic separation and reversible elution of TIMS sample isotopes using the structure of embodiment 1.

[0052] A working method of a TIMS sample isotope automatic separation and reversible elution device comprises the following steps:

[0053] 1. Place ion exchange resins and sieve plates 3.4 inside the 8 chromatography columns 3, place the resin layer columns one by one into the column clamps 2.2, control the column clamps 2.2 to clamp the resin layer columns through the finger cylinder switch on the workbench 1.5, adjust the height of the receiving funnel 3.3 and fix it in the upper clamp 2.7, and adjust the height of the drip head 3.3 and fix it in the lower clamp 2.9.

[0054] 2. Put corresponding hydrochloric acid solution and ultrapure water into 8 elution reagent bottles 1.3. After the treated sample solution containing the target isotope is dripped into the chromatographic column funnel and dripped completely, set the dripping time of each reagent in the controller, and control the switch of the solenoid valve 1.2. The controller controls the automatic liquid addition work. First, open the solenoid valve 1.2 of the two elution reagent bottles, and 2.5 mol / L hydrochloric acid reagent is dripped into the chromatographic column 3 through the burette 1.1. After the titration time of the 2.5 mol / L hydrochloric acid reagent is over, close the solenoid valve 1.2, and collect the Rb and Sr isotope samples in the corresponding elution sections respectively.

[0055] 3. The controller controls the elution motor 1.4 to rotate 45°, and then opens the solenoid valves 1.2 of the two elution reagent bottles 1 and 2, and the 2.5mol / L hydrochloric acid reagent and the 5.0mol / L hydrochloric acid reagent are dripped into the corresponding chromatography column 3 through the burette 1.1. After the titration of the 2.5mol / L hydrochloric acid reagent and the 5.0mol / L hydrochloric acid reagent is completed, the corresponding solenoid valves 1.2 are closed respectively.

[0056] 4. After the longest titration time set in the single solenoid valve 1.2 is over, the controller controls the elution motor 1.4 to rotate 45° again, and then opens the solenoid valves 1.2 of the two elution reagent bottles 1, the two elution reagent bottles 2 and the two elution reagent bottles 3, and 2.5mol / L hydrochloric acid reagent, 5.0mol / L hydrochloric acid reagent and 6.0mol / L hydrochloric acid reagent are dripped into the corresponding chromatography column 3 through the burette 1.1. After the titration of 2.5mol / L hydrochloric acid reagent, 5.0mol / L hydrochloric acid reagent and 6.0mol / L hydrochloric acid reagent is completed, the corresponding solenoid valves 1.2 are closed respectively.

[0057] 5. After the longest titration time set in the single solenoid valve 1.2 is over, the controller controls the elution motor 1.4 to rotate 45° again, and then opens the solenoid valves 1.2 of the two elution reagent bottles 1, the two elution reagent bottles 2, the two elution reagent bottles 3 and the two elution reagent bottles 4, and 2.5mol / L hydrochloric acid reagent, 5.0mol / L hydrochloric acid reagent, 6.0mol / L hydrochloric acid reagent and 18.2MΩ / cm ultrapure water are dripped into the corresponding chromatography column 3 through the burette 1.1. After the titration of 2.5mol / L hydrochloric acid reagent, 5.0mol / L hydrochloric acid reagent, 6.0mol / L hydrochloric acid reagent and 18.2MΩ / cm ultrapure water is completed, the corresponding solenoid valves 1.2 are closed respectively.

[0058] 6. Add appropriate amount of hydrochloric acid reagents of the first two concentrations into each chromatography column for natural flow elution, and collect Rb and Sr isotope samples in the corresponding elution sections respectively.

[0059] 7. After receiving the Sr isotope sample, the reverse elution motor controls the resin layer column to rotate 180°, the funnel joint is inserted into the small trumpet joint on the upper part of the resin layer column, and the small trumpet joint at the lower part of the resin layer column is extended into the large trumpet joint. At this time, open the elution reagent bottle and add three drops of 6.0 mol / L hydrochloric acid reagent to achieve natural flow reverse elution; and receive the rare earth element sample; to receive the Nd isotope alone, the rare earth element sample needs to be separated and purified with Ln resin, and finally the chromatography column is eluted with an appropriate amount of 6.0 mol / L hydrochloric acid reagent to regenerate it, and the column is washed with ultrapure water until neutral.

[0060] 8. After the elution is completed, remove the sample cup, then remove the resin layer column, and store it in a beaker filled with ultrapure water to prepare for the next elution operation. The funnel joint, resin layer column, and drip head are all newly processed for each operation.

[0061] The distribution coefficients of different elements in ion exchange resins are the basis of element purification and separation. The differences in the distribution coefficients of elements in different acids can be used to design efficient element purification processes, and are therefore widely used in modern high-precision and high-accuracy element and isotope analysis.

[0062] Ion exchange resins can be divided into two categories: cation exchange resins and anion exchange resins according to the chemically active groups embedded in the three-dimensional network structure. They exchange ions with cations, anions or ion groups in the solution.

[0063] The chromatographic column 3 is an ion exchange column. Ion exchange column separation is a very efficient element purification technology and is widely used in the separation and purification of Sr, Nd, Pb, Hf, Os radiogenic isotopes and B, Li, Mg, K, Ca, Ba, Fe, Cr, Sr, Cd, Rb, Si, V, Sb, W, U, Re non-traditional stable isotopes.

[0064] Modern high-precision non-traditional stable isotope geochemical analysis needs to take into account both high purity and high recovery (close to 100%), that is, it is necessary to build a quantitative purification process. To achieve this goal, it is necessary to establish an effective purification process through precise experimental design and systematic elution curve calibration based on the understanding of the distribution behavior of each element on the resin. Therefore, comprehensive acquisition of the distribution coefficients of various elements in ion exchange resins is the basis for the development of various high-precision isotope analysis methods.

[0065] In actual applications, strongly acidic cation exchange resins and strongly basic anion exchange resins are often pre-converted into sodium and chlorine types that no longer have strong acidity or strong alkalinity but still retain other properties. During the ion exchange process, sodium-type resins release sodium ions instead of hydrogen ions, avoiding side effects such as a decrease in the pH value of the solution and the resulting corrosion of equipment. Similarly, during the ion exchange process, chlorine-type resins release chloride ions instead of hydroxide ions, avoiding an increase in the pH value of the solution. Both sodium-type and chlorine-type resins use salt water as a regeneration agent during regeneration, without the need for strong acids and strong bases.

[0066] During the elution process of the cationic resin AG50W×12 (100-200 mesh), most of the major elements in the rock sample were eluted out quickly, and the elution order roughly followed was that the alkali metal elements were eluted from light to heavy, while the rare earth elements were strongly adsorbed by the resin due to their large distribution coefficient (especially the light rare earth). The volume of the eluent is proportional to the length of the chromatography column. Under the same eluent conditions, reverse elution greatly reduces the elution volume, thereby improving the enrichment efficiency of the elements.

[0067] The present invention is not limited to the above-mentioned implementation modes, and anyone should be aware of the structural changes made under the enlightenment of the present invention, and all those having the same or similar technical solutions as the present invention fall within the protection scope of the present invention.

[0068] The techniques, shapes, and structural parts not described in detail in the present invention are all well-known techniques.

Claims

1. A working method of a TIMS sample isotope automatic separation and reversible elution device, characterized in that: The working method of the TIMS sample isotope automatic separation and reversible elution device adopts a TIMS sample isotope automatic separation and reversible elution device, which comprises a rotary elution mechanism and a reverse elution mechanism, wherein the rotary elution mechanism is provided with a burette and a rotating frame, the rotating frame adopts a disc-shaped structure, the rotating frame is connected to the elution motor through a rotating column, the elution motor controls the rotating frame to rotate at a fixed angle, a plurality of elution reagent bottles are evenly installed on the rotating frame, a burette is installed at the lower part of the elution reagent bottle, a chromatography column is arranged below the burette, and a sample receiving bottle is placed below the chromatography column; The chromatography column comprises a liquid receiving funnel at the top, a resin layer column at the middle and a liquid dropping head at the bottom. The three-part structure formed by the liquid receiving funnel, the resin layer column and the liquid dropping head is a split structure. The reverse elution mechanism is provided with a finger cylinder and a reverse elution motor. The finger cylinder clamps the resin layer column in the middle of the chromatography column. The rear of the finger cylinder is connected to the motor shaft of the reverse elution motor. The reverse elution motor drives the finger cylinder and the resin layer column to rotate for reverse elution. The working method of the TIMS sample isotope automatic separation and reversible elution device comprises the following steps: S1. Place ion exchange resins and sieve plates inside 8 chromatography columns, place the resin layer columns into the column clamps one by one, control the column clamps to clamp the resin layer columns through the finger cylinder switch on the workbench, adjust the height of the receiving funnel to fix it in the upper clamp, and adjust the height of the drip head to fix it in the lower clamp; S2. Put the corresponding hydrochloric acid solution and ultrapure water into 8 elution reagent bottles. After the treated sample solution containing the target isotope is dripped into the chromatographic column receiving funnel and dripped completely, set the dripping time of each reagent in the controller, and control the switch of the solenoid valve. The controller controls the automatic liquid addition work. First, open the solenoid valves of the two elution reagent bottles, and drip 2.5 mol / L hydrochloric acid reagent into the chromatographic column through the burette. After the titration time of 2.5 mol / L hydrochloric acid reagent is over, close the solenoid valve. S3, the controller controls the elution motor to rotate 45°, then opens the solenoid valves of the two elution reagent bottles 1 and 2, and the 2.5mol / L hydrochloric acid reagent and the 5.0mol / L hydrochloric acid reagent are dripped into the corresponding chromatography columns through the burette. After the titration of the 2.5mol / L hydrochloric acid reagent and the 5.0mol / L hydrochloric acid reagent is completed, the corresponding solenoid valves are closed respectively; S4, after the longest titration time in the set single solenoid valve is over, the controller controls the elution motor to rotate 45° again, and then opens the solenoid valves of two elution reagent bottles one, two elution reagent bottles two and two elution reagent bottles three, and 2.5mol / L hydrochloric acid reagent, 5.0mol / L hydrochloric acid reagent and 6.0mol / L hydrochloric acid reagent are dripped into the corresponding chromatography column through the burette, and after the titration of 2.5mol / L hydrochloric acid reagent, 5.0mol / L hydrochloric acid reagent and 6.0mol / L hydrochloric acid reagent is completed, the corresponding solenoid valves are closed respectively; S5. After the longest titration time in the set single solenoid valve is over, the controller controls the elution motor to rotate 45° again, and then opens the solenoid valves of two elution reagent bottles one, two elution reagent bottles two, two elution reagent bottles three and two elution reagent bottles four, and 2.5mol / L hydrochloric acid reagent, 5.0mol / L hydrochloric acid reagent, 6.0mol / L hydrochloric acid reagent and 18.2MΩ / cm ultrapure water are dripped into the corresponding chromatography column through the burette. After the titration of 2.5mol / L hydrochloric acid reagent, 5.0mol / L hydrochloric acid reagent, 6.0mol / L hydrochloric acid reagent and 18.2MΩ / cm ultrapure water is completed, the corresponding solenoid valves are closed respectively; S6. Control each column to add appropriate amount of hydrochloric acid reagents of the first two concentrations for natural flow elution, and collect Rb and Sr isotope samples in the corresponding elution sections respectively; S7. After receiving the Sr isotope sample, the reverse elution motor controls the resin layer column to rotate 180°, the small trumpet joint on the upper part of the resin layer column extends into the large trumpet joint, and the funnel joint is inserted into the small trumpet joint at the lower part of the resin layer column. At this time, open the elution reagent bottle and add three drops of 6.0 mol / L hydrochloric acid reagent to achieve natural flow reverse elution; and receive the rare earth element sample; if only Nd isotope is to be received, the rare earth element sample needs to be separated and purified with Ln resin, and finally the chromatography column is eluted with an appropriate amount of 6.0 mol / L hydrochloric acid reagent to regenerate it, and the column is washed with ultrapure water until it is neutral; S8. After the elution is completed, remove the sample cup, then remove the resin layer column, and store it in a beaker filled with ultrapure water to prepare for the next elution operation.

2. The working method of the TIMS sample isotope automatic separation and reversible elution device according to claim 1, characterized in that: The chromatography column is made of polytetrafluoroethylene or high-purity quartz material. The liquid receiving funnel on the upper part of the chromatography column receives the reagent dripped from the elution reagent bottle. The resin layer column in the middle of the chromatography column is provided with upper and lower sieve plates, a resin layer is arranged between the two sieve plates, and ion exchange resin is encapsulated in the resin layer.

3. The working method of the TIMS sample isotope automatic separation and reversible elution device according to claim 2, characterized in that: A funnel joint is installed at the bottom of the liquid receiving funnel, small horn joints are installed at both ends of the resin layer column, and a large horn joint is installed on the top of the dripping head. The funnel joint, the small horn joint and the large horn joint are all made of soft rubber material. The funnel joint extends into the small horn joint at the top, and the small horn joint at the bottom extends into the large horn joint. After the resin layer column is rotated back to its original position, the liquid receiving funnel, the resin layer column and the dripping head automatically form an internal through channel.

4. The working method of the TIMS sample isotope automatic separation and reversible elution device according to claim 1, characterized in that: There are 8 elution reagent bottles, including two elution reagent bottles one, two elution reagent bottles two, two elution reagent bottles three and two elution reagent bottles four. The angles between two adjacent elution reagent bottles and the center of the rotating frame are both 45°. The elution reagent bottle one contains 2.5 mol / L hydrochloric acid reagent, the elution reagent bottle two contains 5.0 mol / L hydrochloric acid reagent, the elution reagent bottle three contains 6.0 mol / L hydrochloric acid reagent, and the elution reagent bottle four contains 18.2 MΩ / cm ultrapure water.

5. The working method of the TIMS sample isotope automatic separation and reversible elution device according to claim 4, characterized in that: The bottom of the elution reagent bottle is connected to a burette through a liquid pipeline, and a solenoid valve is installed on the liquid pipeline.

6. The working method of the TIMS sample isotope automatic separation and reversible elution device according to claim 1, characterized in that: The middle part of the rotating frame is fixedly connected to a rotating column, which is rotatably mounted on a workbench through a bearing. The workbench is arranged on an electric control box, in which a washing motor is installed. The motor shaft of the washing motor is connected to the bottom of the rotating column, and an angle encoder is installed on the washing motor.

7. The working method of the TIMS sample isotope automatic separation and reversible elution device according to claim 6, characterized in that: 8 groups of motor brackets are installed on the workbench, a reverse elution motor is installed on the motor bracket, an angle encoder is installed on the reverse elution motor, a motor shaft of the reverse elution motor is fixedly connected to a cylinder mounting seat, a finger cylinder is installed on the other side of the cylinder mounting seat, column clamps are installed on two finger clamps of the finger cylinder, and a buffer pad is provided on the inner side of the column clamp.

8. The working method of the TIMS sample isotope automatic separation and reversible elution device according to claim 7, characterized in that: An upper clip bracket and a lower clip bracket are also installed on the motor bracket. The upper clip is installed on the upper clip bracket, and the lower clip is installed on the lower clip bracket. The upper clip and the lower clip both use two butt-jointed semicircular splints. The outer sides of the semicircular splints are fixedly connected by bolts. The upper clip clamps the tube body at the lower part of the liquid receiving funnel, and the lower clip clamps the tube body at the upper part of the drip head.

9. The working method of the TIMS sample isotope automatic separation and reversible elution device according to claim 6, characterized in that: A controller is installed in the electrical control box, and the controller is electrically connected to the rinsing motor, 8 groups of solenoid valves, 8 groups of reverse rinsing motors, 8 groups of finger cylinders and an electric control switch. The electric control switch is installed on a workbench, and the electric control switch includes a power switch, a start switch, a pause switch, an emergency stop switch and 8 finger cylinder switches.

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