A non-contact micro-droplet electro-synthesis device and synthesis method

Abstract

The present disclosure provides a non-contact micro-droplet electro-synthesis device and a synthesis method, relating to the technical field of electrochemistry. The synthesis device includes a reaction cell generator and a spray generator. The reaction cell generator includes a first high-voltage power supply and a liquid supply device, and is used for generating charged large droplets, with the charged large droplets serving as a reaction cell. The spray generator includes a second high-voltage power supply, a first spray member and a second spray member. Under the second high voltage, the first spray member and the second spray member generate charged micro-droplets, and the charged micro-droplets enter the charged large droplets and rotate and mix for reaction. Using the charged large droplets as a reaction cell, the charged micro-droplets form a non-contact electro-synthesis system by means of droplet soft landing. The synthesis device has a simple structure and low power consumption, and has application value in the field of green organic synthesis.

Description

Technical Field

[0001] The present disclosure relates to the field of green chemistry and, in particular, to a non-contact micro-droplet electro-synthesis device and a synthesis method thereof. Background Art

[0002] As an important branch of organic chemical synthesis, electro-chemical synthesis has broad application prospects in the field of green chemistry.

[0003] However, traditional electro-chemical synthesis mainly uses solid or membrane positive and negative electrodes to perform synthesis through electron gain and loss at the solution interface. In this synthesis method, the efficiency of electron gain and loss determines the electro-chemical synthesis efficiency. And the efficiency of electron gain and loss is controlled by physical properties such as the dielectric properties of the solution, the diffusion constant of the solute, and the diffusion coefficient of the solute at the electrode interface.

[0004] Improving the efficient mass transfer process at the electrode and solution interface can effectively promote the electro-chemical reaction efficiency, especially in the field of electro-synthesis characterized by radical chemistry, which has potential application value.

[0005] It should be noted that the information disclosed in the above background art section is only used to enhance the understanding of the background of the present disclosure, and thus may include information that does not constitute the prior art known to those of ordinary skill in the art. Summary of the Invention

[0006] Based on this, the present disclosure provides a non-contact micro-droplet electro-synthesis device and a synthesis method thereof, which can achieve electro-chemical synthesis without relying on solid or membrane electrodes, have characteristics such as non-contact and efficient mass transfer, and are easy to combine with microfluidic technology and expand to the field of mass spectrometry detection, realizing characteristics such as digital controllability and real-time on-line analysis and detection.

[0007] The first aspect of the present disclosure provides a non-contact micro-droplet electro-synthesis device, including:

[0008] A reaction cell generator, including a first high-voltage power supply and a liquid supply device, the first high-voltage power supply is electrically connected to the liquid supply device, and the liquid supply device generates charged large droplets under the first high voltage, and uses the charged large droplets as a reaction cell;

[0009] A spray generator, including: a second high-voltage power supply, a first spray member and a second spray member, the second high-voltage power supply is respectively electrically connected to the first spray member and the second spray member, and under the second high voltage, the first spray member and the second spray member generate charged micro-droplets;

[0010] The spraying directions of the first spraying member and the second spraying member face the large droplets, so that the generated charged micro-droplets enter the charged large droplets. The polarities of the first high voltage and the second high voltage are opposite, so that the charged micro-droplets and the charged large droplets rotate and mix under the action of the electric field force to carry out a reaction.

[0011] In an exemplary embodiment of the present disclosure, a DC power supply is connected between the first spraying member and the second spraying member. The positive pole of the DC power supply is connected to the first spraying member, and the negative pole is connected to the second spraying member.

[0012] In an exemplary embodiment of the present disclosure, the distance between the spraying ends of the first spraying member and / or the second spraying member and the spraying end of the liquid supply device is 0 to 40 mm.

[0013] In an exemplary embodiment of the present disclosure, the liquid supply device, the first spraying member and the second spraying member all include a pump, a syringe and a capillary. The pump is used to output the liquid in the syringe. The syringe is communicated with the capillary. The syringe has a metal needle. The first high-voltage power supply is electrically connected to the metal needle of the liquid supply device, and the second high-voltage power supply is electrically connected to the metal needles of the first spraying member and the second spraying member.

[0014] In an exemplary embodiment of the present disclosure, both the first high-voltage power supply and the second high-voltage power supply are provided with grounding terminals.

[0015] In an exemplary embodiment of the present disclosure, the inner diameters of the capillaries of the first spraying member and the second spraying member are both 5 to 150 μm; the inner diameter of the capillary of the liquid supply device is 200 to 540 μm.

[0016] In an exemplary embodiment of the present disclosure, the included angle between the capillary of the first spraying member and / or the second spraying member and the capillary of the liquid supply device is 30 to 70°; and / or, the included angle between the capillary of the first spraying member and the capillary of the second spraying member is 60 to 140°.

[0017] The second aspect of the present disclosure provides a non-contact micro-droplet electro-synthesis method, which applies the non-contact micro-droplet electro-synthesis device as described above, and includes:

[0018] Input solution a and solution b into the first spraying member and the second spraying member respectively, and apply a second high voltage to the first spraying member and the second spraying member. Solution a and solution b are atomized into charged micro-droplets;

[0019] Input solution c into the liquid supply device and apply a first high voltage to the liquid supply device. The solution c forms charged large droplets through the principle of electrohydrodynamics, and the first high voltage has the opposite polarity to the second high voltage. Under the interaction of the electric fields formed by the high voltages of opposite polarities, the charged large droplets rotate at high speed;

[0020] The charged micro-droplets fly towards the charged large droplets and react at the interface of the charged large droplets by means of droplet soft landing.

[0021] In an exemplary embodiment of the present disclosure, the first spraying member and the second spraying member are respectively connected to the positive and negative electrodes of an adjustable DC power supply, and the voltage of the adjustable DC power supply is -10.0 to +10.0V.

[0022] In an exemplary embodiment of the present disclosure, the magnitude of the first high voltage is 4 to 7 kV, and the magnitude of the second high voltage is 3 to 5.5 kV.

[0023] In an exemplary embodiment of the present disclosure, the solution c is a polar solvent; or the solution c contains a conductive additive or a catalyst.

[0024] In an exemplary embodiment of the present disclosure, control the flow rate of the solution a and / or the solution b in the capillary to be 10 to 50 μL / min; control the flow rate of the solution c in the capillary to be 50 to 200 μL / min.

[0025] The beneficial effects of the non-contact micro-droplet electro-synthesis device and synthesis method of the embodiments of the present disclosure are:

[0026] 1. Utilize the charged characteristics of the charged micro-droplets formed by electrospray as the positive and negative electrodes of the electrochemical reaction, which can avoid the contact conduction between the traditional metal or composite membrane electrode and the reactants, and integrate the electrode and the reactants on the micro-droplets formed by electrospray. The structure is simple and easy to apply.

[0027] 2. The flight speed of the micro-droplets formed by electrospray is 56 - 84 m / s, which has an incomparable mass transfer efficiency compared with the traditional electrochemical process.

[0028] 3. In the droplet soft landing system formed by electrospray and charged large droplets, the large droplets rotate at high speed, which helps the positively and negatively charged micro-droplet reactants to mix quickly.

[0029] 4. By adjusting the polarity of the high voltage of the charged large droplets, the catalyst in the large droplets can diffuse to the droplet surface under the action of its own electric field, increasing the contact efficiency between the catalyst and the reactants, and helping to improve the reaction catalytic efficiency.

[0030] 5. By increasing the high voltage applied by the charged large droplets, it helps the large droplets to form a new electrospray, which is combined with a mass spectrometry system for in-situ, on-line analysis and detection as well as capturing reaction intermediates, and has broad application scenarios.

[0031] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and do not limit the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the following will briefly introduce the drawings required in the embodiments. It should be understood that the following drawings only show some embodiments of the present disclosure, and thus should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0033] Figure 1 Synthesis schematic diagram of the non-contact micro-droplet electro-synthesis device for the embodiments of the present disclosure;

[0034] Figure 2 Structural schematic diagram of the non-contact micro-droplet electro-synthesis device for the embodiments of the present disclosure;

[0035] Figure 3 Droplet generation diagram for step (1) in Test Example 1 of the present disclosure;

[0036] Figure 4 Droplet generation diagram for step (2) in Test Example 1 of the present disclosure;

[0037] Figure 5 Droplet generation diagram for step (3) in Test Example 1 of the present disclosure;

[0038] Figure 6 Droplet generation diagram for step (1) in Test Example 2 of the present disclosure;

[0039] Figure 7 Droplet generation diagram for step (2) in Test Example 2 of the present disclosure;

[0040] Figure 8 Droplet generation diagram for step (3) in Test Example 2 of the present disclosure;

[0041] Figure 9 Flight conditions of charged large droplets and charged micro-droplets in Test Example 3 of the present disclosure;

[0042] Figure 10 Structural schematic diagram of the synthesis device for Embodiment 1 of the present disclosure;

[0043] Figure 11 Electrospray mass spectrometry diagram without applying DC voltage in Embodiment 1 of the present disclosure;

[0044] Figure 12 This is the electrospray mass spectrometry diagram with a DC voltage of 0.5V in Example 1 of the present disclosure;

[0045] Figure 13 This is the electrospray mass spectrometry diagram with a DC voltage of -0.2V in Example 2 of the present disclosure;

[0046] Figure 14 This is the electrospray mass spectrometry diagram with a DC voltage of 0.28V in Example 2 of the present disclosure;

[0047] Figure 15 This is the chromatogram in Example 3 of the present disclosure. Detailed implementation manners

[0048] To make the objectives, technical solutions, and advantages of the embodiments of the present disclosure clearer, the technical solutions in the embodiments of the present disclosure will be clearly and completely described below. For those conditions not specified in the embodiments, they are carried out according to conventional conditions or the conditions recommended by the manufacturer. For those reagents or instruments not specified by the manufacturer, they are all conventional products that can be obtained through commercial purchase.

[0049] The non-contact micro-droplet electro-synthesis device and synthesis method of the embodiments of the present disclosure will be specifically described below.

[0050] Please refer to Figure 1 As shown, this is the synthesis schematic diagram of the non-contact micro-droplet electro-synthesis device of the present disclosure. The non-contact micro-droplet electro-synthesis device includes a reaction cell generator 100 and a spray generator 200. The reaction cell generator 100 generates charged large droplets 10, and the spray generator 200 generates a spray to form charged micro-droplets 20. Since the high-voltage polarities applied to the reaction cell generator 100 and the spray generator 200 are opposite, the charged large droplets 10 rotate self-spontaneously under the action of the electric field. Using the self-rotating charged large droplets 10 as the reaction cell, the spray-formed charged micro-droplets 20 enter the charged large droplets 10 by means of soft landing and perform an electrochemical reaction on the interface surface of the charged large droplets 10.

[0051] Specifically, please refer to Figure 2 , the reaction cell generator 100 includes a first high-voltage power supply 6 and a liquid supply device. The first high-voltage power supply 6 is electrically connected to the liquid supply device. The liquid supply device generates charged large droplets under the first high voltage, and uses the charged large droplets as the reaction cell. Further, the liquid supply device includes a pump 1, a syringe 2, and a capillary 8. The syringe 2 and the capillary 8 are connected through a two-way joint 3. The pump 1 can be, for example, a metering pump, and the flow rate of the liquid in the capillary 8 is controlled by the metering pump 1. The syringe 2 has a metal needle, and the first high-voltage power supply 6 is electrically connected to the metal needle of the syringe 2 through a wire 5 to provide the first high voltage. Further, the first high-voltage power supply 6 is provided with a grounding terminal 7 to ensure safety.

[0052] The spray generator 200 includes a second high-voltage power supply 18, a first spray member and a second spray member. The second high-voltage power supply 18 is electrically connected to the first spray member and the second spray member respectively. Under the second high voltage, the first spray member and the second spray member generate charged micro-droplets. Specifically, the first spray member includes a pump 12, a syringe 11 and a capillary 9. The syringe 11 and the capillary 9 are connected through a two-way joint 10. The second spray member includes a pump 12, a syringe 21 and a capillary 19. The syringe 21 and the capillary 19 are connected through a two-way joint 20. The second spray member includes a pump 12, a syringe 11 and a capillary 9. The syringe 11 and the capillary 9 are connected through a two-way joint 10. The flow rate of the liquid in the capillaries 9 and 19 is controlled by the pump 12. Both the syringes 11 and 21 have metal needles. The second high-voltage power supply 18 is connected to the metal needles of the syringes 11 and 21 through wires 13 to provide the second high voltage. Further, the second high-voltage power supply 18 is provided with a ground terminal 17 to ensure safety.

[0053] In this embodiment, the spray directions of the first spray member and the second spray member are towards the large droplets, so that the generated charged micro-droplets enter the charged large droplets. The polarities of the first high voltage and the second high voltage are opposite, so that the charged micro-droplets and the charged large droplets rotate and mix under the action of the electric field force to carry out a reaction.

[0054] In an exemplary embodiment of the present disclosure, the distance between the spray end of the first spray member and / or the second spray member and the spray end of the liquid supply device is 0 to 40 mm.

[0055] It can be understood that the spray end is the capillary tip of the device. By controlling the distance between the first spray member, the second spray member and the liquid supply device, it is ensured that the charged micro-droplets can softly land on the surface of the charged large droplets.

[0056] Further, the angle between the capillary of the first spray member and / or the second spray member and the capillary of the liquid supply device is 30 to 70°. The angles between the capillaries of the first spray member and the second spray member and the capillary of the liquid supply device can be the same or different. More preferably, in this embodiment, the angles between the capillaries of the first spray member and the second spray member and the capillary of the liquid supply device are both 45 to 70°.

[0057] Further, the angle between the capillary of the first spray member and the capillary of the second spray member is 60 to 140°. More preferably, the angle between the two is 70 to 140°.

[0058] By adjusting the angles between the capillaries of the first spray member, the second spray member and the liquid supply device, the direction of the electrospray is regulated to promote the flight of the charged micro-droplets towards the charged large droplets.

[0059] Further, a DC power supply 15 is connected between the first spraying member and the second spraying member. The positive pole of the DC power supply 15 is connected to the first spraying member, and the negative pole of the DC power supply 15 is connected to the second spraying member. Specifically, as Figure 2 shown, the DC power supply is an adjustable DC power supply and is connected with a switch 16. The voltmeter 14 is connected in parallel with the DC power supply 15 and the switch 16. By adjusting different voltages of the DC power supply 15, a specific voltage difference is formed between the first spraying member and the second spraying member, so that the charged micro-droplets generated by the two are used as the positive and negative electrodes of the electrochemical reaction, and the self-rotating charged large droplets are used as the reaction pool, and the electrochemical reaction is carried out at the interface of the charged large droplets in a soft landing manner.

[0060] Two electrospray probes with positive and negative polarities are formed through the DC power supply and are used as the positive and negative electrodes of the electrochemical synthesis reaction. The two positive and negative electrodes do not make direct contact with the reaction solute. The non-contact mainly refers to the positive and negative electrodes of the electro-synthesis device, which are formed by the two electrospray probes, and have the characteristics such as "always new when in use" on the electrode surface, and there is no mass transfer and diffusion effect in the traditional electrochemical reaction.

[0061] Further, the inner diameters of the capillaries of the first spraying member and the second spraying member are both 5 - 150 μm; the inner diameter of the capillary of the liquid supply device is 200 - 540 μm. The inner diameters of the first spraying member and the second spraying member are smaller to form charged micro-droplets, and the inner diameter of the liquid supply device is larger to form charged large droplets as the reaction pool.

[0062] The embodiment of the present disclosure also provides a non-contact micro-droplet electro-synthesis method, which applies the non-contact micro-droplet electro-synthesis device as above, including:

[0063] S1, input solution a and solution b into the first spraying member and the second spraying member respectively, and apply a second high voltage to the first spraying member and the second spraying member, and solution a and solution b are atomized into charged micro-droplets;

[0064] S2, input solution c into the liquid supply device, and apply a first high voltage to the liquid supply device. Solution c forms charged large droplets through the electrohydrodynamic principle, and the first high voltage and the second high voltage have opposite polarities. Under the interaction of the electric fields formed by the positive and negative high voltages, the charged large droplets rotate at a high speed;

[0065] S3, the charged micro-droplets fly towards the direction of the charged large droplets and react at the interface of the charged large droplets in a soft landing manner.

[0066] Further, the synthesis method further includes:

[0067] S4, the first spraying member and the second spraying member are respectively connected to the positive pole and the negative pole of the adjustable DC power supply, and the voltage of the DC power supply is controlled to be -10.0 - +10.0 V.

[0068] Solution a and solution b are atomized into charged micro-droplets at the capillary tips of the first spraying member and the second spraying member via the electrohydrodynamic principle; solution c forms charged large droplets at the capillary tip of the liquid supply device via the electrohydrodynamic principle. The DC power supply between the first spraying member and the second spraying member is regulated to form a specific voltage difference therebetween, so that an electrochemical reaction occurs at the interface of the charged large droplets between solution a and solution b.

[0069] It can be understood that the present disclosure does not limit the specific order of steps S1 - S4. For example, solution a, solution b, and solution c can be input simultaneously, etc.

[0070] Further, solution c is a polar solvent; or solution c contains a conductive additive; or solution c contains a specific catalyst. In one embodiment, solution c is a solution with a relatively high polarity, such as water, ethanol, glycerol, propylene glycol, etc. In another embodiment, the conductivity of solution c can also be increased by adding a conductive additive to solution c. The conductive additive can be, for example, an ionic liquid, etc. The catalyst is, for example, a component that can accelerate the reaction between solution a and solution b, such as a nickel catalyst, a copper catalyst, etc.

[0071] Further, the flow rate of solution a and / or solution b in the capillary is controlled to be 10 - 50 μL / min; the flow rate of solution c in the capillary is controlled to be 50 - 200 μL / min. By controlling the flow rate of the solution and the magnitude of the voltage, the micro-droplets have an extremely fast flying speed, realizing efficient mass transfer. Through experimental detection, the flying speed of the charged micro-droplets reaches 56 - 84 m / s, which has an incomparable mass transfer efficiency compared with the traditional electrochemical process.

[0072] Further, the magnitude of the first high voltage is 4 - 7 kV, and the magnitude of the second high voltage is 3 - 5.5 kV. By changing the magnitude of the first high voltage or the second high voltage, the reaction process of the electrochemical reaction can be regulated to meet different reaction requirements. By adjusting and increasing the first high voltage, components such as the catalyst in the charged large droplets can diffuse to the droplet surface under the action of its own electric field, increasing the contact effect between the catalyst and other components and the reactants, and improving the reaction efficiency.

[0073] In addition, adjusting and increasing the first high voltage also helps the large droplets to form a new electrospray, which can be combined with a mass spectrometry system for in-situ, on-line analysis and detection, and capturing reaction intermediates, etc.

[0074] The features and properties of the present disclosure are further described in detail below in conjunction with embodiments.

[0075] Test Example 1 Electrochemical Reaction Test of Aqueous Solution

[0076] (1) AsFigure 3 As shown, the liquid supply device 110, the first spraying member 210, and the second spraying member 220 all pump out the aqueous solution through a metering pump. The liquid supply device 110 applies +4 kV, and the first spraying member 210 and the second spraying member 220 apply 0 kV. The results show that droplets matching their inner diameters are respectively formed at the capillary tips of the liquid supply device 110, the first spraying member 210, and the second spraying member 220.

[0077] (2) As Figure 4 shown, the voltages of the first spraying member 210 and the second spraying member 220 are adjusted to -3 kV. The results show that electrospray is formed at the capillary tips of the first spraying member 210 and the second spraying member 220 and sprayed onto the surface of the charged large droplets. Under the action of a strong electric field, the charged large droplets rotate and mix rapidly, forming a stirring and mixing function similar to that in conventional electro-synthesis.

[0078] It can be seen that by applying voltages of different polarities to the liquid supply device 110, the first spraying member 210, and the second spraying member 220, it can be applied to the electrochemical synthesis in an aqueous system.

[0079] (3) As Figure 5 shown, the voltages of the first spraying member 210 and the second spraying member 220 are adjusted to -3 kV, and the voltage of the liquid supply device 110 is +7 kV. The results show that the charged large droplets serving as the reaction cell form an electrospray under the drive of a high voltage.

[0080] If the synthesis device is combined with a mass spectrometry instrument, the reaction intermediates can be captured, and the reactants in the charged large droplets can be detected, or the reaction process can be monitored.

[0081] Test Example 2 Electrochemical Reaction Test in Organic Solvent

[0082] (1) As Figure 6 shown, the reaction conditions of the synthesis device are as follows:

[0083] The liquid supply device 110 is +4 kV, and the reaction solution is dichloromethane (DCM);

[0084] The first spraying member 210 and the second spraying member 220 are -3 kV, and the reaction solution is water.

[0085] The results show that under the set positive and negative high voltage values, due to the poor conductivity of the organic solvent, no spraying state is formed in the liquid supply device 110, the first spraying member 210, and the second spraying member 220.

[0086] (2) As Figure 7 shown, the reaction conditions of the synthesis device are as follows:

[0087] The liquid supply device 110 is +4 kV, and the reaction solution is ethanol (EtOH);

[0088] The first spraying member 210 and the second spraying member 220 are at -3 kV, and the reaction solution is water.

[0089] The results show that ethanol has a certain electrical conductivity under the set positive and negative high voltage values. At the initial stage, electrospray will form at the capillary tips of the first spraying member 210 and the second spraying member 220. After about 30 s, the electrospray disappears.

[0090] (3) As Figure 8 shown, the reaction conditions of the synthesis device are as follows:

[0091] The liquid supply device 110 is at +4 kV, and the reaction solution is ethanol (EtOH) and tetrabutylammonium hexafluorophosphate ionic liquid ([NBu4][PF6]);

[0092] The first spraying member 210 and the second spraying member 220 are at -3 kV, and the reaction solution is water.

[0093] The results show that electrospray continuously forms at the capillary tips of the first spraying member 210 and the second spraying member 220 under the set positive and negative high voltage values.

[0094] It can be seen that this synthesis device can be applied to the electrochemical synthesis of organic solvent systems.

[0095] Test Example 3 Charged Droplet Soft Landing Test

[0096] (1) The reaction conditions of the synthesis device are as follows:

[0097] The liquid supply device is at +6 kV, and the reaction solution is water; the first spraying member and the second spraying member are at 0 kV, and the reaction solution is water.

[0098] Figure 9 (a) shows the flight conditions of charged large droplets and charged micro-droplets under the above conditions. As Figure 9 (a) shows, during the flight process from time 0 - 8 ms, the micro-droplets fly deviating from the surface of the large droplet.

[0099] (2) The reaction conditions of the synthesis device are as follows:

[0100] The liquid supply device is at +6 kV, and the reaction solution is water; the first spraying member and the second spraying member are at +3 kV, and the reaction solution is water.

[0101] Figure 9 (b) shows the flight conditions of charged large droplets and charged micro-droplets under the above conditions. As Figure 9 (b) shows, during the process of 4 - 8 ms, the micro-droplets always travel along the curvature of the large droplet.

[0102] (3) The reaction conditions of the synthesis device are as follows:

[0103] The liquid supply device is +6 kV, and the reaction liquid is water; the first spraying member and the second spraying member are -3 kV, and the reaction liquid is water.

[0104] Figure 9 (c) shows the flight conditions of charged large droplets and charged micro-droplets captured by a high-speed camera under the above conditions. As Figure 9 (c) shows, during the flight process from time 0 - 8 ms, the micro-droplets contact the large droplets at 6 ms and merge into the large droplets.

[0105] Example 1

[0106] This example provides a non-contact electro-synthesis method of micro-droplets based on thiol oxidation, which is carried out using the Figure 2 shown synthesis device. Among them, the reaction conditions of the synthesis device are as follows:

[0107] Liquid supply device: +7 kV, the reaction liquid is water; the first spraying member, the second spraying member: -3 kV, the reaction liquid is glutathione aqueous solution.

[0108] As Figure 10 shown, the synthesis device is used in combination with a mass spectrometer 300, and the mixed spray is detected by the mass spectrometer 300, and the obtained mass spectrum is as Figure 11 shown. In the negative ion mode, Figure 11 on the mass spectrum, there are two mass spectrometry peaks with relatively high abundances of mass-to-charge ratio (m / z), 306.0729 and 613.1497, as well as low abundances of 338.0568 and 354.0524, which are respectively matched as [GSH-H] - , [2GSH-H] - , [GSH + 2O - H] - and [GSH + 3O - H] - . Among them, [2GSH-H] - is the dimer of GSH formed during the electrospray process. [GSH + 2O - H] - and [GSH + 3O - H] - are trace amounts of sulfinic acid and sulfonic acid formed by the oxidation of GSH during the electrospray process.

[0109] After further applying a 0.5 V DC voltage between the first spraying member and the second spraying member, the obtained mass spectrum is as Figure 12 shown. Figure 12 Among them, the abundance of [GSH-H] - with a mass-to-charge ratio (m / z) of 306.0729 is significantly reduced. On the contrary, the mass-to-charge ratio (m / z) of [GSH + 2O - H] -and [GSH+3O-H] - The abundance is significantly increased compared with that before applying the DC voltage. It should be noted that [2GSH-H] at 613.1497 - almost completely disappears, and is replaced by the newly emerged peak of [GS-SG-H] at 611.1389 - .

[0110] Comparison Figure 11 and Figure 12 The results show that when a DC voltage of 0.5 V is applied to the first spraying part and the second spraying part of the synthesis device, the oxidation peak of the mercapto group in glutathione is significantly enhanced. Moreover, by comparing the peak intensities of the oxidation products, the peak intensity of the disulfide bond formed under the influence of electron loss is significantly enhanced. The results further illustrate that regulating the DC voltage has good selectivity for regulating the oxidation of the mercapto group.

[0111] Example 2

[0112] This example provides a non-contact microdroplet electro-synthesis method based on a mercapto-olefin reaction system, which is carried out by using the synthesis device shown Figure 2 . The reaction conditions of the synthesis device are as follows:

[0113] Liquid supply device: +7 kV, the reaction solution is water;

[0114] First spraying part: -3.5 kV, the reaction solution is cysteine (Cys,2) dissolved in an aqueous solution

[0115] Second spraying part: -3.5 kV, the reaction solution is methyl 2-(hydroxy-phenyl-methyl)-acrylate (HPMACE,1) dissolved in ethanol.

[0116] The DC voltage between the first spraying part and the second spraying part is set to -0.2 V.

[0117] The sprayed product after the reaction is detected by a mass spectrometer, and the obtained mass spectrum is as shown Figure 13 . Among them, the electrochemical reaction process is as follows:

[0118]

[0119] Cysteine (121.0197) and methyl 2-(hydroxy-phenyl-methyl)-acrylate (192.0786) undergo a Michael addition reaction to generate reactant 3 with a molecular weight of 313.0984.

[0120] Mass spectrum Figure 13 The results show that in the positive ion mode, the ion peaks at m / z of 122.0269, 193.0859 and 175.0754 are cysteine [2+H] + , [1+H] +and [1-H2O+H] + , mainly the relevant ion peaks of reactants 1 and 2. Obviously, the ion peak at m / z 314.1057 is [3+H] formed after the addition reaction of reaction products 1 and 2. + of the ion peak.

[0121] Further optimize and adjust the DC voltage of the electro-synthesis. The DC voltage is -0.28V; the obtained mass spectrometry is as Figure 14 shown. As Figure 14 shown, the mass spectrometry ion peaks of reactants 1 and 2 are significantly reduced and almost invisible. However, the peak of the product at m / z 314.1057 is significantly enhanced, and a new ion peak at m / z 296.0965 appears, which is the ion peak formed after the dehydration of product 3, that is, [3-H2O+H]. + . This result shows that optimizing the DC voltage of this electro-synthesis device can effectively regulate the reaction efficiency.

[0122] Example 3

[0123] This example provides a non-contact micro-droplet electro-synthesis method based on a thiol-alkene reaction system, which is carried out using the Figure 2 shown synthesis device. Among them, the reaction conditions of the synthesis device are as follows:

[0124] Liquid supply device: +4kV, the reaction solution is an aqueous solution;

[0125] The first spraying part: -3kV, the reaction solution is cysteine (Cys,2) dissolved in an aqueous solution

[0126] The second spraying part: -3kV, the reaction solution is methyl 2-(hydroxy-phenyl-methyl)-acrylate (HPMACE,1) dissolved in ethanol.

[0127] The DC voltage between the first spraying part and the second spraying part is set to -0.28V.

[0128] Collect the charged large droplets after the reaction and perform chromatographic analysis. The chromatogram is as Figure 15 shown.

[0129] Refer to Figure 15 , Figure 15 above is the chromatogram of the bulk reaction, and below is the chromatogram of the micro-droplet electro-synthesis reaction of this example. Among them, the reaction conditions of the bulk reaction are: mix cysteine (Cys,2) dissolved in an aqueous solution and methyl 2-(hydroxy-phenyl-methyl)-acrylate (HPMACE,1) dissolved in ethanol, and magnetically stir the reaction at room temperature for 2.5h to obtain the reaction product.

[0130] From the chromatographic results, the retention times of cysteine (Cys, 2) and methyl 2-(hydroxy-phenyl-methyl)-acrylate (HPMACE, 1) are 1.6 and 9.2 min, respectively, while the retention time of the reaction product is between 4.1 - 6.0 min. For the bulk reaction, there are two reaction products 2# and 4#, while for the microdroplet electrosynthesis method, there are four reaction products 1#, 2#, 3# and 4#. Among them, 2# and 4# exist due to the presence of chiral carbon atoms, while the existence of 1# and 3# products is caused by the microdroplet reaction reducing the reaction barrier and promoting different modes of addition of the mercapto group to the olefin.

[0131] The embodiments described above are some, but not all, of the embodiments of the present disclosure. The detailed description of the embodiments of the present disclosure is not intended to limit the scope of the claimed present disclosure, but merely represents selected embodiments of the present disclosure. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present disclosure without creative efforts fall within the scope of protection of the present disclosure.

Claims

1. A non-contact micro-droplet electro-synthesis device, characterized in that, Comprising: A reaction cell generator, comprising a first high-voltage power supply and a liquid supply device, the first high-voltage power supply being electrically connected to the liquid supply device, the liquid supply device generating charged large droplets under a first high voltage, and using the charged large droplets as a reaction cell; A spray generator, comprising: a second high-voltage power supply, a first spray member and a second spray member, the second high-voltage power supply being electrically connected to the first spray member and the second spray member respectively, and under a second high voltage, the first spray member and the second spray member generating charged micro-droplets; The spray directions of the first spray member and the second spray member are oriented towards the large droplets, so that the generated charged micro-droplets are incorporated into the charged large droplets by means of droplet soft landing, and the polarities of the first high voltage and the second high voltage are opposite, so that the charged micro-droplets and the charged large droplets rotate and mix under the action of an electric field force to carry out a reaction; The liquid supply device, the first spray member and the second spray member each comprise a pump, a syringe and a capillary tube, the pump being used to output the liquid in the syringe, the syringe being in communication with the capillary tube, the syringe having a metal needle, the first high-voltage power supply being electrically connected to the metal needle of the liquid supply device, and the second high-voltage power supply being electrically connected to the metal needles of the first spray member and the second spray member.

2. The non-contact micro-droplet electro-synthesis device according to claim 1, wherein A DC power supply is connected between the first spray member and the second spray member, the positive pole of the DC power supply being connected to the first spray member and the negative pole being connected to the second spray member.

3. The non-contact micro-droplet electro-synthesis device according to claim 1, characterized in that, The distance between the spray end of the first spray member and / or the second spray member and the spray end of the liquid supply device is 0 to 40 mm.

4. The non-contact micro-droplet electro-synthesis device according to claim 1, wherein Both the first high-voltage power supply and the second high-voltage power supply are provided with grounding terminals.

5. The non-contact micro-droplet electro-synthesis device according to claim 1, characterized in that, The inner diameters of the capillary tubes of the first spray member and the second spray member are both 5 to 150 μm; the inner diameter of the capillary tube of the liquid supply device is 200 to 540 μm.

6. The non-contact micro-droplet electro-synthesis device according to claim 1, characterized in that The angle between the capillary tube of the first spray member and / or the second spray member and the capillary tube of the liquid supply device is 30 to 70°; and / or, the angle between the capillary tube of the first spray member and the capillary tube of the second spray member is 60 to 140°.

7. A non-contact micro-droplet electro-synthesis method, which applies the non-contact micro-droplet electro-synthesis device described in any one of claims 1 to 6, characterized in that, Comprising: Inputting solution a and solution b into the first spray member and the second spray member respectively, and applying a second high voltage to the first spray member and the second spray member, so that solution a and solution b are atomized into charged micro-droplets; Inputting solution c into the liquid supply device, and applying a first high voltage to the liquid supply device, so that solution c forms charged large droplets through electrohydrodynamics, and the first high voltage and the second high voltage have opposite polarities, and under the interaction of the electric fields formed by the positive and negative high voltages, the charged large droplets rotate at a high speed; The charged micro-droplets fly towards the direction of the charged large droplets and react at the interface of the charged large droplets by means of droplet soft landing.

8. The non-contact micro-droplet electro-synthesis method according to claim 7, characterized in that, Comprising: The first spraying member and the second spraying member are respectively connected to the positive and negative electrodes of an adjustable DC power supply, and the voltage of the adjustable DC power supply is -10.0 to +10.0 V; the magnitude of the first high voltage is 4 to 7 kV, and the magnitude of the second high voltage is 3 to 5.5 kV; Control the flow rate of the solution a and / or the solution b in the capillary to be 10 to 50 μL / min; control the flow rate of the solution c in the capillary to be 50 to 200 μL / min.

9. The non-contact micro-droplet electro-synthesis method according to claim 7, characterized in that, The solution c is a polar solvent; or the solution c contains a conductive additive or a catalyst.

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