Method and system for producing wet electronic grade hydrochloric acid

Abstract

The present application provides a method and system for producing wet electronic-grade hydrochloric acid. The method of the present application comprises the following steps: filtering the raw hydrochloric acid to remove mechanical impurities therein; passing the filtered raw hydrochloric acid through a resin adsorption device to perform iron removal and mercury removal operations to obtain wet electronic-grade hydrochloric acid. In the method of the present application, iron and mercury in the hydrochloric acid are removed by resin adsorption. The process does not require heating, so it has the characteristics of energy saving, and overcomes the traditional production of electronic-grade hydrochloric acid, which uses distillation, rectification and other methods, and requires heating and consumes a lot of energy. And the resin adsorption method is also easy to operate and easy to maintain.

Description

Technical Field

[0001] The present application relates to the technical field of electronic chemical production, and in particular to a method and system for producing wet electronic-grade hydrochloric acid. Background Art

[0002] Electronic chemicals, also known as electronic chemical materials, broadly refer to fine chemical materials specially used for the electronics industry, including electronic components, integrated circuits, printed circuit boards, industrial and consumer machine production and packaging of various chemicals and materials. In a narrow sense, it can refer to wet electronic chemicals, also known as ultra-pure reagents, which are considered to be liquid chemicals used in large quantities in liquid crystal display panels, solar cells and integrated circuits, mainly for cleaning, photolithography, development, touch-off and doping.

[0003] Wet electronic-grade hydrochloric acid, also known as electronic-grade hydrochloric acid, is commonly used in the large-scale integrated circuit manufacturing industry, such as high-temperature vapor phase etching of silicon and gallium arsenide before epitaxial growth, cleaning of sodium ions, and chemical treatment of metal surfaces. It is one of the important reagents in the electronics industry. With the rapid development of the country's photovoltaic industry and new energy, the demand for electronic-grade hydrochloric acid is increasing. Although many companies are conducting research and development of electronic-grade hydrochloric acid, due to the high technical requirements for the production of electronic-grade hydrochloric acid, little progress has been made.

[0004] Electronic grade hydrochloric acid is mostly made of industrial grade 31% hydrochloric acid containing impurities, which is purified and refined into high-purity hydrochloric acid. At present, the purification process of hydrochloric acid mainly includes isothermal diffusion method, sub-boiling method, distillation method and rectification method. Among them, the isothermal diffusion method and sub-boiling method have small output. Although the obtained hydrochloric acid has high purity, they are only suitable for experimental small-scale production of high-purity hydrochloric acid and have no industrial use value. The distillation method has a large output, but the obtained hydrochloric acid is not of high purity and the concentration is not too high. Rectification is the mainstream technology for purifying hydrochloric acid at present. Although the output is large, the equipment is relatively complex, and the distillation process requires a lot of energy to heat the raw materials, resulting in high energy consumption. Summary of the invention

[0005] The present application provides a method and system for producing wet electronic grade hydrochloric acid, which are used to solve the problems of high energy consumption and complicated operation caused by the existing production of wet electronic grade hydrochloric acid using distillation and other methods.

[0006] In a first aspect, the present application provides a method for producing wet electronic grade hydrochloric acid, comprising the following steps:

[0007] Filter the raw hydrochloric acid to remove mechanical impurities;

[0008] The filtered raw hydrochloric acid is passed through a resin adsorption device to perform iron removal and mercury removal operations to obtain wet electronic grade hydrochloric acid.

[0009] The method of the present application has the following beneficial effects:

[0010] 1) Iron and mercury in hydrochloric acid are removed by resin adsorption. This process does not require heating, so it has the characteristics of energy saving. It overcomes the disadvantages of traditional production of electronic grade hydrochloric acid using distillation, rectification and other methods, which require heating and consume a lot of energy.

[0011] 2) In the method of the present application, a resin is used to purify hydrochloric acid, and the active groups on the resin can selectively adsorb the impurity ions in the raw hydrochloric acid. For example, in the process of iron removal, the resin can selectively adsorb the iron ions and other high-valent metal cations in the hydrochloric acid, and the resin does not react with HCl in the process of adsorbing metal cations, which can effectively reduce the loss of HCl. In addition, due to the high selectivity of the resin, it lays a foundation for improving the quality of the raw hydrochloric acid.

[0012] 3) The resin adsorption method is easy to operate and the equipment is easy to maintain. In addition, the resin purification has the advantages of large processing capacity and easy regeneration.

[0013] 4) The raw material hydrochloric acid used is widely available and easy to obtain.

[0014] Optionally, the raw hydrochloric acid includes industrial grade hydrochloric acid or raw hydrochloric acid prepared by the following method:

[0015] The hydrogen and chlorine are introduced into the synthesis furnace respectively and burned to obtain hydrogen chloride;

[0016] The hydrogen chloride is absorbed by an absorbing liquid to obtain raw hydrochloric acid;

[0017] The concentration of the raw hydrochloric acid is 30-40 wt %.

[0018] Optionally, when filtering the raw hydrochloric acid, at least one level of filtering device is used for filtering;

[0019] During the filtering process, the filtering accuracy is 0.2-1 μm.

[0020] Optionally, the iron removal operation is:

[0021] The hydrochloric acid treated in the previous step is passed through a device filled with a resin capable of adsorbing iron ions, and the flow rate is controlled to be 0.5 to 25 L / min;

[0022] During the iron removal operation, the hydrochloric acid is iron removed by at least one device having a resin capable of adsorbing iron ions;

[0023] The resin capable of adsorbing iron ions has a particle size of 0.40 to 0.50 mm and a pore size of 1.2 to 1.5 μm;

[0024] The resin capable of adsorbing iron ions includes quaternary ammonium anion exchange resin and / or strong acid cation exchange resin.

[0025] Optionally, the mercury removal operation is:

[0026] The hydrochloric acid treated in the previous step is passed through a device filled with a resin capable of absorbing mercury ions, and the flow rate is controlled to be 0.5 to 25 L / min;

[0027] During the mercury removal operation, the hydrochloric acid is demercured by at least two stages of resins capable of absorbing mercury ions;

[0028] The resin capable of adsorbing mercury ions has a particle size of 0.50 to 0.65 mm and a pore size of 1.2 to 1.5 μm;

[0029] The resin capable of adsorbing mercury ions contains one or more active functional groups selected from the group consisting of thiol, thiourea, amide, amino, carboxyl, phosphate, aldehyde, sulfonic acid, and imino-disulfide bonds.

[0030] Optionally, the filtered raw hydrochloric acid is first subjected to an iron removal operation and then to a mercury removal operation, or first subjected to a mercury removal operation and then to an iron removal operation;

[0031] During the iron removal and mercury removal operations, the inlet and outlet liquid temperatures are controlled at 5-20°C.

[0032] Optionally, the molar ratio of chlorine to hydrogen is 1:1.02-1.05;

[0033] The absorption liquid includes deionized water, and the temperature of the absorption liquid is 5-20°C.

[0034] In a second aspect, the present application provides a system for producing wet electronic grade hydrochloric acid, the system comprising:

[0035] A raw hydrochloric acid storage tank, a pressure pump, a filtering device, an iron removal adsorption device, a mercury removal adsorption device and a wet electronic grade hydrochloric acid storage tank connected in series;

[0036] The filtering device is arranged in multiple stages in series;

[0037] The iron removal adsorption device shall be provided with at least one stage;

[0038] The mercury removal adsorption device is arranged in multiple stages in series.

[0039] The beneficial effects of the system for producing wet electronic-grade hydrochloric acid provided in the present application are as described in the first aspect above and will not be repeated here.

[0040] Optionally, the raw hydrochloric acid storage tank is connected to the hydrochloric acid production device;

[0041] The hydrochloric acid production device comprises a synthesis furnace, a condenser and a hydrogen chloride absorption device connected in series, and the hydrogen chloride absorption device is connected to a raw material hydrochloric acid storage tank;

[0042] The synthesis furnace is connected to the hydrogen supply device through the first flame arrester, and the synthesis furnace is connected to the chlorine supply device through the second flame arrester;

[0043] The hydrogen chloride absorption device comprises a multi-stage series-connected hydrogen chloride absorption tower, wherein the gas input end of the first-stage hydrogen chloride absorption tower is connected to the gas output end of the condenser, and the liquid output end is connected to the raw material hydrochloric acid storage tank;

[0044] Between two adjacent hydrogen chloride absorption towers, the gas output end of the upper hydrogen chloride absorption tower is connected to the gas input end of the lower hydrogen chloride absorption tower, and the liquid input end of the upper hydrogen chloride absorption tower is connected to the liquid output end of the lower hydrogen chloride absorption tower;

[0045] The gas output end of the last stage hydrogen chloride absorption tower is connected to the tail gas treatment device through a fan, and the liquid input end is connected to the absorption liquid storage tank through a circulation pump. A first valve is provided between the liquid input end of the last stage hydrogen chloride absorption tower and the circulation pump;

[0046] The absorption liquid storage tank is also connected to the ejector, the ejector is also connected to the circulation pump through the second valve, and the ejector is also connected to the gas output end of the raw hydrochloric acid storage tank.

[0047] Optionally, the raw hydrochloric acid storage tank is connected to the input end of the pressure pump via a third valve;

[0048] The wet electronic grade hydrochloric acid storage tank is connected to the input end of the booster pump through the fourth valve.

[0049] Optionally, the iron removal adsorption device is a resin column filled with a resin capable of adsorbing iron ions;

[0050] The mercury removal adsorption device is a resin column filled with a resin capable of adsorbing mercury ions. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, a brief introduction will be given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0052] Figure 1 A schematic diagram of a system for producing wet electronic grade hydrochloric acid provided in one embodiment of the present application;

[0053] Figure 2 A schematic diagram of a hydrochloric acid production device provided in one embodiment of the present application;

[0054] Figure 3 A schematic diagram of a system for producing wet electronic grade hydrochloric acid provided in another embodiment of the present application.

[0055] Explanation of the reference numerals: 1. raw hydrochloric acid storage tank; 2. filtering device; 3. iron removal adsorption device; 4. mercury removal adsorption device; 5. wet electronic grade hydrochloric acid storage tank; 6. synthesis furnace; 7. hydrogen chloride absorption device; 8. absorption liquid storage tank; 10. booster pump; 60. condenser; 61. first flame arrester; 62. hydrogen supply device; 63. second flame arrester; 64. chlorine supply device; 71. hydrogen chloride absorption tower; 72. fan; 73. tail gas treatment device; 81. circulation pump; 82. ejector; 100. first valve; 200. second valve; 300. third valve; 400. fourth valve. DETAILED DESCRIPTION

[0056] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application is clearly and completely described below. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work also fall within the scope of protection of the present application.

[0057] In a first aspect, the present application provides a method for producing wet electronic grade hydrochloric acid, comprising the following steps:

[0058] Filter the raw hydrochloric acid to remove mechanical impurities;

[0059] The filtered raw hydrochloric acid is passed through a resin adsorption device to perform iron removal and mercury removal operations to obtain wet electronic grade hydrochloric acid.

[0060] In the present application, the resin adsorption device for iron removal is filled with ion exchange resin, and the active groups on the resin exchange ions with the iron ions in the raw hydrochloric acid, thereby removing the iron ions mixed in the raw hydrochloric acid, and also removing the high-valent cations such as calcium and magnesium mixed in the raw hydrochloric acid. Mercury ions are not easily removed during the ion exchange process, so a resin with active groups that bind or chelate with mercury ions can be used to remove mercury ions, and the mercury ions in the raw hydrochloric acid are adsorbed to remove the mercury ions.

[0061] The method of the present application has the following beneficial effects:

[0062] 1) Iron and mercury in hydrochloric acid are removed by resin adsorption. This process does not require heating, so it has the characteristics of energy saving. It overcomes the disadvantages of traditional production of electronic grade hydrochloric acid using distillation, rectification and other methods, which require heating and consume a lot of energy.

[0063] 2) In the method of the present application, a resin is used to purify hydrochloric acid, and the active groups on the resin can selectively adsorb the impurity ions in the raw hydrochloric acid. For example, in the process of iron removal, the resin can selectively adsorb the iron ions and other high-valent metal cations in the hydrochloric acid, and the resin does not react with HCl in the process of adsorbing metal cations, which can effectively reduce the loss of HCl. In addition, due to the high selectivity of the resin, it lays a foundation for improving the quality of the raw hydrochloric acid.

[0064] 3) The resin adsorption method is easy to operate and the equipment is easy to maintain. In addition, the resin purification has the advantages of large processing capacity and easy regeneration.

[0065] 4) The raw material hydrochloric acid used is widely available and easy to obtain.

[0066] Optionally, the raw hydrochloric acid includes industrial grade hydrochloric acid or raw hydrochloric acid prepared by the following method:

[0067] The hydrogen and chlorine are introduced into the synthesis furnace respectively and burned to obtain hydrogen chloride;

[0068] The hydrogen chloride is absorbed by an absorbing liquid to obtain raw hydrochloric acid;

[0069] The concentration of the raw hydrochloric acid is 30-40 wt %.

[0070] Optionally, when filtering the raw hydrochloric acid, at least one level of filtering device is used for filtering;

[0071] During the filtering process, the filtering accuracy is 0.2-1 μm.

[0072] In the present application, filtering the raw hydrochloric acid can not only remove mechanical impurities in the raw hydrochloric acid and improve the cleanliness of the raw hydrochloric acid; but also, as a pre-process for resin adsorption treatment of the raw hydrochloric acid, filtering also has the effect of protecting the resin and reducing the blockage of the pores in the resin.

[0073] The resin adsorption device includes a device filled with a resin capable of adsorbing iron ions and a device filled with a resin capable of adsorbing mercury ions.

[0074] Optionally, the iron removal operation is: passing the hydrochloric acid treated in the previous step through a device filled with a resin capable of adsorbing iron ions, and controlling the flow rate to be 0.5 to 25 L / min;

[0075] During the iron removal operation, the hydrochloric acid is iron removed by at least one device having a resin capable of adsorbing iron ions;

[0076] The resin capable of adsorbing iron ions has a particle size of 0.40 to 0.50 mm and a pore size of 1.2 to 1.5 μm;

[0077] The resin capable of adsorbing iron ions includes quaternary ammonium anion exchange resin and / or strong acid cation exchange resin.

[0078] In the present application, the structure of the resin capable of adsorbing iron ions is, for example, cross-linked polystyrene, styrene-vinyl copolymer structure, etc., and the components of these structures have good acid resistance.

[0079] In the present application, quaternary ammonium anion exchange resin is used to remove iron ions mixed in the raw hydrochloric acid, including divalent iron ions and trivalent iron ions; high-valent cations such as calcium and magnesium mixed in the raw hydrochloric acid can also be exchanged and removed.

[0080] Optionally, the mercury removal operation is:

[0081] The hydrochloric acid treated in the previous step is passed through a device filled with a resin capable of absorbing mercury ions, and the flow rate is controlled to be 0.5 to 25 L / min;

[0082] During the mercury removal operation, the hydrochloric acid is demercured by at least two stages of resins capable of absorbing mercury ions;

[0083] The resin capable of adsorbing mercury ions has a particle size of 0.50 to 0.65 mm and a pore size of 1.2 to 1.5 μm;

[0084] The resin capable of adsorbing mercury ions contains one or more active functional groups selected from the group consisting of thiol, thiourea, amide, amino, carboxyl, phosphate, aldehyde, sulfonic acid, and imino-disulfide bonds.

[0085] In the present application, the resin capable of adsorbing mercury ions has a structure such as cross-linked polystyrene, styrene-vinyl copolymer structure, etc., and the components of these structures have good acid resistance.

[0086] The above-mentioned active functional groups can effectively combine with mercuric ions to carry out ion exchange. The active functional groups are preferably thiol or thiourea. These two functional groups can selectively combine with mercuric ions to improve the efficiency of mercury removal from hydrochloric acid.

[0087] Optionally, the filtered raw hydrochloric acid is first subjected to an iron removal operation and then to a mercury removal operation, or first subjected to a mercury removal operation and then to an iron removal operation;

[0088] During the iron removal and mercury removal operations, the inlet and outlet liquid temperatures are controlled at 5-20°C.

[0089] In the present application, controlling the treatment temperature at 5-20°C can effectively prevent the adverse consequences of the precipitation of hydrogen chloride in the hydrochloric acid during the treatment process, resulting in a decrease in the hydrochloric acid concentration, and the escape of hydrochloric acid causing damage to the corresponding iron removal and mercury removal resin columns.

[0090] Optionally, the molar ratio of chlorine to hydrogen is 1:1.02-1.05;

[0091] The absorption liquid includes deionized water, and the temperature of the absorption liquid is 5-20°C.

[0092] In the present application, the molar ratio of chlorine to hydrogen is controlled within the range of 1:1.02-1.05 to ensure that chlorine can fully react, thereby avoiding mixing of free chlorine into the synthesis gas, thereby reducing the content of free chlorine in the finished wet electronic grade hydrochloric acid.

[0093] The deionized water of the present application is, for example, three-stage deionized water, and the temperature of the absorption liquid is controlled at 5-20° C. to increase the solubility of hydrogen chloride in the absorption liquid, thereby increasing the concentration of the obtained raw hydrochloric acid.

[0094] like Figure 1 As shown, in a second aspect, the present application provides a system for producing wet electronic grade hydrochloric acid, the system comprising:

[0095] A raw hydrochloric acid storage tank 1, a pressure pump 10, a filtering device 2, an iron removal adsorption device 3, a mercury removal adsorption device 4 and a wet electronic grade hydrochloric acid storage tank 5 are sequentially connected in series;

[0096] The filtering device 2 is arranged in multiple stages in series;

[0097] The iron removal adsorption device 3 is provided with at least one stage;

[0098] The mercury removal adsorption device 4 is arranged in multiple stages in series.

[0099] like Figure 2 As shown, optionally, the raw hydrochloric acid storage tank 1 is connected to the hydrochloric acid production device;

[0100] The hydrochloric acid production device comprises a synthesis furnace 6, a condenser 60 and a hydrogen chloride absorption device 7 which are connected in series in sequence, and the hydrogen chloride absorption device 7 is connected to a raw material hydrochloric acid storage tank 1;

[0101] The synthesis furnace 6 is connected to the hydrogen supply device 62 through the first flame arrester 61, and the synthesis furnace 6 is connected to the chlorine supply device 64 through the second flame arrester 63;

[0102] The hydrogen chloride absorption device 7 comprises a multi-stage series-connected hydrogen chloride absorption tower 71, wherein the gas input end of the first stage hydrogen chloride absorption tower 71 is connected to the gas output end of the condenser 60, and the liquid output end is connected to the raw hydrochloric acid storage tank 1;

[0103] Between two adjacent hydrogen chloride absorption towers 71, the gas output end of the upper hydrogen chloride absorption tower 71 is connected to the gas input end of the lower hydrogen chloride absorption tower 71, and the liquid input end of the upper hydrogen chloride absorption tower 71 is connected to the liquid output end of the lower hydrogen chloride absorption tower 71;

[0104] The gas output end of the last stage hydrogen chloride absorption tower 71 is connected to the tail gas treatment device 73 through the fan 72, and the liquid input end is connected to the absorption liquid storage tank 8 through the circulation pump 81. A first valve 100 is provided between the liquid input end of the last stage hydrogen chloride absorption tower 71 and the circulation pump 81;

[0105] The absorption liquid storage tank 8 is also connected to the ejector 82 , and the ejector 82 is also connected to the circulation pump 81 through the second valve 200 . The ejector 82 is also connected to the gas output end of the raw hydrochloric acid storage tank 1 .

[0106] like Figure 3 As shown, optionally, the raw hydrochloric acid storage tank 1 is connected to the input end of the booster pump 10 via a third valve 300;

[0107] The wet electronic grade hydrochloric acid storage tank 5 is connected to the input end of the booster pump 10 through the fourth valve 400 .

[0108] In the present application, the above-mentioned connection method is used to repeatedly treat the product in the wet electronic grade hydrochloric acid storage tank 5 using the filtering device 2, the iron removal adsorption device 3 and the mercury removal adsorption device 4, so as to further improve the purity of the obtained product.

[0109] Optionally, the iron removal adsorption device 3 is a resin column filled with a resin capable of adsorbing iron ions;

[0110] The mercury removal adsorption device 4 is a resin column filled with a resin capable of adsorbing mercury ions.

[0111] In the present application, the resin filled in the iron removal adsorption device 3 has a height of 1.6 to 2.0 m and a cross-sectional area of ​​1.02 to 1.15 m 2 ; The filling parameters of the resin in the mercury removal adsorption device 4 are the same as those in the iron removal adsorption device 3.

[0112] A system for producing wet electronic grade hydrochloric acid, the working process of which is as follows:

[0113] When in use, the hydrogen supplied by the hydrogen supply device 62 (such as a hydrogen pipeline, a hydrogen storage tank, etc.) is introduced into the synthesis furnace 6 through the first flame arrester 61, and burns with the chlorine supplied by the chlorine supply device 64 (such as a chlorine pipeline, a liquid chlorine storage tank, etc.) through the second flame arrester 63 in the synthesis furnace 6, and simultaneously generates a synthesis gas with hydrogen chloride gas as the main component, wherein the molar ratio of chlorine and hydrogen supplied into the synthesis furnace 6 is 1:1.02-1.05 to ensure complete reaction of chlorine and avoid mixing of free chlorine into hydrogen chloride. The synthesis gas is output from the synthesis furnace 6, cooled by the condenser 60 (to 30-50° C.), and then input into the first-stage hydrogen chloride absorption tower 71 of the hydrogen chloride absorption device 7, and is contacted with the dilute hydrochloric acid output from the next-stage hydrogen chloride absorption tower 71 in parallel or countercurrent flow to absorb hydrogen chloride, thereby forming hydrochloric acid with a higher concentration. The hydrogen chloride and other water-insoluble gases that cannot be absorbed are input into the next-stage hydrogen chloride absorption tower 71 for reabsorption, until the last-stage hydrogen chloride absorption tower 71 is absorbed by the absorption liquid (deionized water in this application, such as tertiary demineralized water) supplied from the absorption liquid storage tank 8, and the generated tail gas is sucked from the last-stage hydrogen chloride absorption tower 71 by the fan 72 and discharged into the tail gas treatment device 73 for centralized treatment.

[0114] The hydrochloric acid absorbed by the hydrogen chloride absorption device 7 is the raw hydrochloric acid with a concentration of 30-40wt%, which is transferred to the raw hydrochloric acid storage tank 1 for temporary storage. During the storage process, some hydrogen chloride gas or acid mist will overflow from the raw hydrochloric acid. At this time, the circulation pump 81 can be opened, the first valve 100 can be closed and the second valve 200 can be opened. The liquid flow input by the circulation pump 81 is used to form a negative pressure in the ejector 82 to absorb the hydrogen chloride gas or acid mist in the raw hydrochloric acid storage tank 1 to avoid waste of resources. In the normal absorption of hydrogen chloride, the second valve 200 is closed and the first valve 100 is opened to ensure that the absorption liquid can be supplied to the hydrogen chloride absorption device 7. Specific embodiments

[0116] Example 1

[0117] A wet electronic grade hydrochloric acid is produced as follows:

[0118] S101, introducing hydrogen and chlorine into a synthesis furnace respectively for combustion to obtain hydrogen chloride, wherein the molar ratio of chlorine to hydrogen is 1:1.02;

[0119] S102, cooling the hydrogen chloride and absorbing it with deionized water at 5° C. to obtain raw hydrochloric acid with a concentration of 40 wt %;

[0120] S103, filtering the raw hydrochloric acid through a secondary filter with a filtration accuracy of 0.2 to 1 μm;

[0121] S104, passing the filtered raw hydrochloric acid through a primary iron removal resin column for iron removal, wherein the resin in the resin column is a quaternary ammonium anion resin with a styrene-diethylene copolymer framework, and the flow rate is 0.5 L / min; the inlet and outlet liquid temperatures are controlled at 5°C.

[0122] S105. The hydrochloric acid after iron removal is passed through a two-stage mercury removal resin to remove mercury to obtain wet electronic grade hydrochloric acid. The resin in the resin column is a polystyrene-structured resin in which the active functional group is thiourea. The flow rate is 1.0 L / min. The inlet and outlet liquid temperatures are controlled at 5°C.

[0123] Example 2

[0124] A wet electronic grade hydrochloric acid is produced as follows:

[0125] S201, introducing hydrogen and chlorine into a synthesis furnace respectively for combustion to obtain hydrogen chloride, wherein the molar ratio of chlorine to hydrogen is 1:1.05;

[0126] S202, cooling the hydrogen chloride and absorbing it with deionized water at 20° C. to obtain raw hydrochloric acid with a concentration of 30 wt %;

[0127] S203, filtering the raw hydrochloric acid through a secondary filter with a filtration accuracy of 0.2 to 1 μm;

[0128] S204, passing the filtered raw hydrochloric acid through a primary iron removal resin column for iron removal, wherein the resin in the resin column is a quaternary ammonium anion resin with a styrene-diethylene copolymer framework, and the flow rate is 25 L / min; the inlet and outlet liquid temperatures are controlled at 20°C.

[0129] S205. The hydrochloric acid after iron removal is passed through a two-stage mercury removal resin to remove mercury to obtain wet electronic grade hydrochloric acid. The resin in the resin column is a polystyrene-structured resin in which the active functional group is thiourea. The flow rate is 25 L / min. The inlet and outlet liquid temperatures are controlled at 20°C.

[0130] Example 3

[0131] A wet electronic grade hydrochloric acid is produced as follows:

[0132] S301, introducing hydrogen and chlorine into a synthesis furnace respectively for combustion to obtain hydrogen chloride, wherein the molar ratio of chlorine to hydrogen is 1:1.03;

[0133] S302, cooling the hydrogen chloride and absorbing it with deionized water at 15° C. to obtain raw hydrochloric acid with a concentration of 36 wt %;

[0134] S303, filtering the raw hydrochloric acid through a secondary filter with a filtration accuracy of 0.2 to 1 μm;

[0135] S304, passing the filtered raw hydrochloric acid through a primary iron removal resin column for iron removal, wherein the resin in the resin column is a quaternary ammonium anion resin with a styrene-diethylene copolymer framework, and the flow rate is 10 L / min; the inlet and outlet liquid temperatures are controlled at 15°C.

[0136] S305. The hydrochloric acid after iron removal is passed through a two-stage mercury removal resin to remove mercury to obtain wet electronic grade hydrochloric acid. The resin in the resin column is a polystyrene-structured resin in which the active functional group is thiourea. The flow rate is 10 L / min. The inlet and outlet liquid temperatures are controlled at 15°C.

[0137] Example 4

[0138] A wet electronic grade hydrochloric acid is produced as follows:

[0139] S401, introducing hydrogen and chlorine into a synthesis furnace respectively for combustion to obtain hydrogen chloride, wherein the molar ratio of chlorine to hydrogen is 1:1.05;

[0140] S402, cooling the hydrogen chloride and absorbing it with deionized water at 5° C. to obtain raw hydrochloric acid with a concentration of 36 wt %;

[0141] S403, filtering the raw hydrochloric acid through a secondary filter with a filtration accuracy of 0.2 to 1 μm;

[0142] S404, passing the filtered raw hydrochloric acid through a primary iron removal resin column for iron removal, wherein the resin in the resin column is a quaternary ammonium anion resin with a styrene-diethylene copolymer framework, and the flow rate is 15 / min; the inlet and outlet liquid temperatures are controlled at 5°C.

[0143] S405. The hydrochloric acid after iron removal is passed through a two-stage mercury removal resin to remove mercury to obtain wet electronic grade hydrochloric acid. The resin in the resin column is a polystyrene-structured resin in which the active functional group is thiourea. The flow rate is 15 L / min. The inlet and outlet liquid temperatures are controlled at 5°C.

[0144] Example 5

[0145] A wet electronic grade hydrochloric acid is produced as follows:

[0146] The remaining operations are the same as those in Example 4, except that the raw hydrochloric acid is industrial-grade hydrochloric acid with a concentration of 36 wt %.

[0147] In the above embodiments, the resin column with a circular cross section is used in the mercury removal and iron removal process. The inner diameter of the resin column is 0.6m, and the resin filling height is 1.8m. The iron removal resin is GS 3000 resin. Mercury removal resin uses TCR resin.

[0148] The finished wet electronic grade hydrochloric acid obtained in the above Examples 1 to 5 was tested using the testing method in GB / T 31369-2015 Electronic Grade Hydrofluoric Acid for Solar Cells. The results are shown in Table 1:

[0149] Table 1

[0150]

[0151]

[0152] The results in Table 1 show that the impurity content in the wet electronic-grade hydrochloric acid prepared by the method of the present application is at an extremely low value, which fully meets the requirements of the corresponding electronic chemicals. In particular, when the molar ratio of hydrogen to chlorine is 1:1.05, no free chlorine (Cl2) is detected in the finished electronic-grade hydrochloric acid, which shows that the raw hydrochloric acid prepared by the method of the present application can control the free chlorine content therein to be below the detection limit; at the same time, when general industrial-grade hydrochloric acid is used as a raw material, the free chlorine content therein is high, but still within the allowable range.

[0153] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, ordinary technicians in the field should understand that they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for producing wet electronic grade hydrochloric acid, characterized in that: The steps include: Filter the raw hydrochloric acid to remove mechanical impurities; The filtered raw hydrochloric acid is passed through a resin adsorption device to perform iron removal and mercury removal operations to obtain wet electronic grade hydrochloric acid.

2. The method for producing wet electronic grade hydrochloric acid according to claim 1, characterized in that: The raw hydrochloric acid includes industrial grade hydrochloric acid or raw hydrochloric acid prepared by the following method: The hydrogen and chlorine are introduced into the synthesis furnace respectively and burned to obtain hydrogen chloride; The hydrogen chloride is absorbed by an absorbing liquid to obtain raw hydrochloric acid; The concentration of the raw hydrochloric acid is 30-40 wt %.

3. The method for producing wet electronic grade hydrochloric acid according to claim 1, characterized in that: When filtering the raw hydrochloric acid, at least one level of filtering device is used for filtering; During the filtering process, the filtering accuracy is 0.2-1 μm.

4. The method for producing wet electronic grade hydrochloric acid according to claim 1, characterized in that: The iron removal operation is as follows: The hydrochloric acid treated in the previous step is passed through a device filled with a resin capable of adsorbing iron ions, and the flow rate is controlled to be 0.5 to 25 L / min; During the iron removal operation, the hydrochloric acid is iron removed by at least one device having a resin capable of adsorbing iron ions; The resin capable of adsorbing iron ions has a particle size of 0.40 to 0.50 mm and a pore size of 1.2 to 1.5 μm; The resin capable of adsorbing iron ions comprises a quaternary ammonium anion exchange resin, and / or a strong acid cation exchange resin; and / or, The hydrochloric acid treated in the previous step is passed through a device filled with a resin capable of absorbing mercury ions, and the flow rate is controlled to be 0.5 to 25 L / min; During the mercury removal operation, the hydrochloric acid is demercured by at least two stages of resins capable of absorbing mercury ions; The resin capable of adsorbing mercury ions has a particle size of 0.50 to 0.65 mm and a pore size of 1.2 to 1.5 μm; The resin capable of adsorbing mercury ions contains one or more active functional groups selected from the group consisting of thiol, thiourea, amide, amino, carboxyl, phosphate, aldehyde, sulfonic acid, and imino-disulfide bonds.

5. The method for producing wet electronic grade hydrochloric acid according to claim 1, characterized in that: The filtered raw hydrochloric acid is first subjected to an iron removal operation and then to a mercury removal operation, or first subjected to a mercury removal operation and then to an iron removal operation; During the iron removal and mercury removal operations, the inlet and outlet liquid temperatures are controlled at 5-20°C.

6. The method for producing wet electronic grade hydrochloric acid according to claim 2, characterized in that: The molar ratio of chlorine to hydrogen is 1:1.02-1.05; The absorption liquid includes deionized water, and the temperature of the absorption liquid is 5-20°C.

7. A system for producing wet electronic grade hydrochloric acid, characterized in that: In the method for producing wet electronic grade hydrochloric acid according to any one of claims 1 to 6, the system comprises: A raw material hydrochloric acid storage tank (1), a pressure pump (10), a filtering device (2), an iron removal adsorption device (3), a mercury removal adsorption device (4) and a wet electronic grade hydrochloric acid storage tank (5) connected in series; The filtering device (2) is arranged in multiple stages in series; The iron removal adsorption device (3) is provided with at least one stage; The mercury removal adsorption device (4) is arranged in multiple stages in series.

8. The system for producing wet electronic grade hydrochloric acid according to claim 7, characterized in that: The raw hydrochloric acid storage tank (1) is connected to a hydrochloric acid production device; The hydrochloric acid production device comprises a synthesis furnace (6), a condenser (60) and a hydrogen chloride absorption device (7) connected in series, and the hydrogen chloride absorption device (7) is connected to a raw material hydrochloric acid storage tank (1); The synthesis furnace (6) is connected to a hydrogen supply device (62) via a first flame arrester (61), and the synthesis furnace (6) is connected to a chlorine supply device (64) via a second flame arrester (63); The hydrogen chloride absorption device (7) comprises a plurality of hydrogen chloride absorption towers (71) connected in series, wherein the gas input end of the first stage hydrogen chloride absorption tower (71) is connected to the gas output end of the condenser (60), and the liquid output end is connected to the raw hydrochloric acid storage tank (1); Between two adjacent hydrogen chloride absorption towers (71), the gas output end of the hydrogen chloride absorption tower (71) of the previous stage is connected to the gas input end of the hydrogen chloride absorption tower (71) of the next stage, and the liquid input end of the hydrogen chloride absorption tower (71) of the previous stage is connected to the liquid output end of the hydrogen chloride absorption tower (71) of the next stage; The gas output end of the last stage hydrogen chloride absorption tower (71) is connected to the tail gas treatment device (73) through a fan (72), and the liquid input end is connected to the absorption liquid storage tank (8) through a circulation pump (81). A first valve (100) is provided between the liquid input end of the last stage hydrogen chloride absorption tower (71) and the circulation pump (81); The absorption liquid storage tank (8) is also connected to the ejector (82), and the ejector (82) is also connected to the circulation pump (81) via the second valve (200). The ejector (82) is also connected to the gas output end of the raw hydrochloric acid storage tank (1).

9. The system for producing wet electronic grade hydrochloric acid according to claim 7, characterized in that: The raw material hydrochloric acid storage tank (1) is connected to the input end of the pressure pump (10) via a third valve (300); The wet electronic grade hydrochloric acid storage tank (5) is connected to the input end of the booster pump (10) via a fourth valve (400).

10. The system for producing wet electronic grade hydrochloric acid according to any one of claims 7 to 9, characterized in that: The iron removal adsorption device (3) is a resin column filled with a resin capable of adsorbing iron ions; The mercury removal adsorption device (4) is a resin column filled with a resin capable of adsorbing mercury ions.

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