System and method for purifying butyl carbitol acetate

Abstract

The invention provides a system and a method for purifying butyl carbitol acetate, the system comprises an adsorption device and a rectification device, the adsorption device comprises an adsorption column and an adsorbent filled in the adsorption column; the rectifying device comprises a rectifying tower and a vacuum pump connected to the top of the rectifying tower. According to the system, butyl carbitol acetate can be purified to an electronic grade, and the application requirement of an organic carrier is well met.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor application materials. Further, it relates to a system and method for purifying butyl carbitol acetate. Background Art

[0002] Electronic paste products are electronic functional materials integrating materials, metallurgy, chemical engineering, and electronic technologies. They are the basic materials for integrated circuits, sensitive components, surface mount technology, resistor networks, displays, and various electronic discrete components, etc.

[0003] After processes such as screen printing, leveling, drying, and sintering, the electronic paste can be cured on substrates such as ceramics to form a conductive film, which is used to manufacture thick film integrated circuits, resistors, resistor networks, capacitors, multilayer ceramic capacitors, conductor inks, solar cell electrodes, light emitting diode (LED) light sources, organic light emitting displays (OLEDs), printed and high-resolution conductors, membrane switches, flexible circuits, conductive adhesives, sensitive components, and other electronic components.

[0004] Electronic paste generally consists of three main components: a conductive phase (functional phase), a binder phase, and an organic carrier. The organic carrier is a solution of a polymer dissolved in an organic solvent. It is a carrier for the functional phase and binder phase particles, and its role is to bear the carrier of the conductive phase and binder phase particles, control the rheological properties of the electronic paste, adjust the viscosity of the paste, and the initial adhesion to the substrate, so that the mixture of the conductive phase, binder phase, and other solid particles in solid form is dispersed into a paste with fluid characteristics, facilitating screen printing onto the substrate to form the required pattern.

[0005] The organic carrier consists of an organic solvent, a thickener, a thixotropic agent, a surfactant, and some auxiliary solvents. The simplest carrier should also include two components, namely an organic solvent and a thickener. The content of the organic solvent accounts for about 65 - 98% of the total mass of the organic carrier. It is a relatively viscous liquid that can provide polar groups, can dissolve thickeners such as cellulose, has a relatively high boiling point, and low volatility at room temperature.

[0006] Existing organic solvents include ethylene glycol ethyl ether acetate, terpineol, butyl carbitol acetate, dibutyl phthalate, etc. Among them, due to the characteristics of high safety (flash point 110°C) and low toxicity, butyl carbitol acetate can effectively avoid the control of geographical factors and is an ideal choice for organic solvents. However, the purity of commercially available butyl carbitol acetate is generally about 96 - 98%, which cannot meet the requirements for application in organic carriers. Summary of the Invention

[0007] To solve the above problems, the present invention provides a system and method for purifying butyl carbitol acetate, which can purify butyl carbitol acetate to the electronic grade.

[0008] First, one of the objectives of the present invention is to provide a system for purifying butyl carbitol acetate.

[0009] Specifically, the system includes an adsorption device and a rectification device. The butyl carbitol acetate raw material is purified successively through the adsorption device and the rectification device. Among them, the adsorption device includes an adsorption column and an adsorbent filled in the adsorption column; the rectification device includes a rectification tower and a vacuum pump connected to the top of the rectification tower.

[0010] Furthermore, the adsorbent is selected from at least one of 4A, 5A, 10X, 13X, ZSM-5, and high-silica Y molecular sieve; preferably, the particle size of the adsorbent is 4 to 20 mesh.

[0011] Furthermore, the adsorbent needs to be pretreated before being filled into the adsorption column. The pretreatment method is: boiling the adsorbent in an acid solution for 2 to 6 hours; among them, the volume of the added acid solution is 1 to 4 times the volume of the adsorbent.

[0012] Furthermore, the acid is selected from one of hydrochloric acid, nitric acid, formic acid, and acetic acid; the mass concentration of the acid solution is 1 to 11%, preferably 2 to 9%, and particularly preferably 3 to 8%.

[0013] Furthermore, the diameter of the adsorption column is 20 to 200 mm, and the aspect ratio (the ratio of the length to the diameter of the adsorption column) is 4 to 10.

[0014] Furthermore, the adsorption device includes at least two adsorption columns connected in series successively. The adsorbents filled in different adsorption columns can be the same or different; preferably, the adsorbents filled in different adsorption columns are different.

[0015] Even further, the adsorption device further includes a cold trap, which is arranged between the outlet of the raw material storage tank and the inlet of the first adsorption column. By cooling the raw material, local overheating is avoided, and a small amount of decomposition of butyl carbitol is prevented. Preferably, the temperature of the cold trap is -10 to 5°C, and more preferably -5 to 0°C.

[0016] Furthermore, the rectification tower includes a tower kettle, a stripping section, a rectification section, and a fractionation section from bottom to top; among them, the stripping section is provided with 2 to 4 trays; the rectification section is provided with 2 to 10 trays; the fractionation section is provided with 6 to 10 trays; the crude product inlet is arranged at the junction of the stripping section and the rectification section; the product outlet is arranged at the junction of the rectification section and the fractionation section; the tower kettle is provided with an N2 inlet.

[0017] Preferably, the material of the rectification tower is selected from one or a combination of stainless steel, quartz, glass, and polytetrafluoroethylene.

[0018] Furthermore, a packing is provided inside the rectification column, and the packing is selected from one or a combination of Raschig rings, Pall rings, θ rings, arc saddle rings, and rectangular saddle rings; preferably, the diameter of the packing is 1 / 15 to 1 / 5 of the column diameter of the rectification column; preferably, the material of the packing is selected from one or a combination of stainless steel, quartz, glass, and polytetrafluoroethylene.

[0019] Furthermore, the rectification device further includes a cooling device. One end of the cooling device is connected to the top of the rectification column, and the other end is connected to a vacuum pump; a waste liquid outlet is provided on the side close to the vacuum pump, and the waste liquid outlet is connected to a waste liquid collection tank.

[0020] Secondly, the second object of the present invention is to provide a method for purifying butyl carbitol acetate.

[0021] Among them, the purification of butyl carbitol acetate is carried out using the system of the first object of the present invention.

[0022] Specifically, the method for purifying butyl carbitol acetate includes the following steps: The crude butyl carbitol acetate first passes through an adsorption device and then is sent into the rectification device for rectification to obtain electronic-grade butyl carbitol acetate.

[0023] Preferably, the purification conditions in the adsorption stage are: the diameter of the adsorption column is 20 to 200 mm; the length-diameter ratio is 4 to 10; the adsorption rate is 3 to 8 BV / h.

[0024] Preferably, the purification conditions in the rectification stage are: the column diameter of the rectification column is 80 to 200 mm; the number of plates in the stripping section is 2 to 14, the number of plates in the rectifying section is 2 to 10, and the number of plates in the fractionating section is 6 to 10; the feed rate is 0.5 to 8 L / min; the flow rate of N2 introduced into the column bottom is 0.5 to 3 L / min; the vacuum degree is 0.5 to 15.0 KPa, preferably 1 to 10 KPa, more preferably 1 to 9 KPa.

[0025] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0026] The present invention can preferably adsorb and remove polymer impurities in industrial raw materials through the adsorption device, and can preferably remove impurities such as diethylene glycol dibutyl ether and diethylene glycol diacetate through the rectification device, thereby obtaining electronic-grade butyl carbitol acetate. The removal method is not only simple, but also has a high recovery rate, and at the same time fills the technical blank of the purification of butyl carbitol acetate. Description of the Drawings

[0027] Figure 1 It is a connection schematic diagram of the adsorption device of the butyl carbitol acetate purification system provided in Embodiment 1 of the present invention;

[0028] Figure 2Schematic connection diagram of the rectification device for the system for purifying butyl carbitol acetate provided in Embodiment 1 of the present invention;

[0029] Reference numerals:

[0030] V1, raw material storage tank; V2, crude product collection tank; V3, finished product collection tank; V4, waste liquid collection tank; B1, peristaltic pump; B2, vacuum pump; T1 and T2, adsorption columns; T3, rectification column; T30, column still; T31, stripping section; T32, rectifying section; T33, fractionating section; D1, cold trap; L1, cooling device. Detailed implementation manners

[0031] The present invention will be specifically described below in conjunction with specific embodiments. It is necessary to point out here that the following embodiments are only for further illustration of the present invention and cannot be construed as limiting the protection scope of the present invention. Some non-essential improvements and adjustments made by those skilled in the art to the present invention based on the content of the present invention still fall within the protection scope of the present invention.

[0032] Embodiment 1

[0033] This embodiment is used to illustrate the system for purifying butyl carbitol acetate. Figure 1 And Figure 2 shows the process flow diagram of the system.

[0034] From Figure 1 and Figure 2 it can be seen that the system includes an adsorption device and a rectification device. The raw material of butyl carbitol acetate is first treated by the adsorption device and then sent to the rectification device for treatment. The treated finished product of butyl carbitol acetate can reach the electronic grade.

[0035] Furthermore, Figure 1 shows the adsorption device, which includes a raw material storage tank V1, a peristaltic pump B1, an adsorption column T1, an adsorption column T2, and a crude product collection tank V2 connected in sequence. Among them, the raw material of butyl carbitol acetate in the raw material storage tank V1 is pushed by the peristaltic machine B1 and passes through the adsorption column T1 and the adsorption column T2 in sequence, and finally is collected at the crude product collection tank V2. The polymer in the industrial raw material can be preliminarily adsorbed and removed through the adsorption device.

[0036] Furthermore, Figure 2 shows the rectification device, including a rectification column T3, a finished product collection tank V3, a waste liquid collection tank V4, a cooling device L1, and a vacuum pump B2. From Figure 2 it can be seen that the crude product collection tank V2 in the adsorption device is connected to the crude product inlet of the rectification column T3 in the rectification device. The crude product of butyl carbitol acetate treated by the adsorption device is sent into the rectification column T3, and the impurities diethylene glycol diacetate and diethylene glycol dibutyl ether are removed by rectification to obtain the finished product of butyl carbitol acetate.

[0037] More specifically, from Figure 2 it can be seen that the rectifying column T3 includes a reboiler T30, a stripping section T31, a rectifying section T32, and a fractionating section T33 from bottom to top; among them, the reboiler T30 is provided with an N2 inlet for reducing the partial pressure of impurities in the gas phase; a crude product inlet is provided between the stripping section T31 and the rectifying section T32, and the crude product inlet is connected to the crude product collection tank V2; a product outlet is provided between the rectifying section T32 and the fractionating section T33, and the product outlet is connected to the finished product collection tank V3; the top of the fractionating section T33 is connected to one end of the cooling device L1, the other end of the cooling device L1 is connected to the vacuum pump B2, and a waste liquid outlet is provided on one side of the cooling device L1 close to the vacuum pump B2, and the waste liquid outlet is connected to the waste liquid collection tank V4.

[0038] During the rectification process, the crude butyl carbitol acetate in the crude product collection tank V2 enters the rectifying column T3 for distillation, the purified product is collected at the finished product collection tank V3 through the product outlet, the impurities are sent out from the top of the rectifying column T3, and after being condensed by the cooling device L1, they are collected at the waste liquid collection tank V4.

[0039] Example 2

[0040] This example is used to illustrate the system for purifying butyl carbitol acetate.

[0041] The system provided in this example is basically the same as the system provided in Example 1, except that a cold trap D1 is further provided on the adsorption device.

[0042] From Figure 1 it can be seen that the cold trap D1 is arranged between the outlet of the raw material storage tank V1 and the inlet of the adsorption column T1, that is, the butyl carbitol acetate raw material in the raw material storage tank V1 is first cooled by passing through the cold trap D1 under the push of the peristaltic pump B1, and then sent into the adsorption column T1. Cooling the raw material through the cold trap can avoid generating a large amount of heat during the adsorption process, resulting in excessive local heat and causing a slight decomposition of butyl carbitol.

[0043] Application Example 1

[0044] This example is used to illustrate the purification of butyl carbitol acetate using the system of Example 1, and the purification process is as follows:

[0045] Conditions for the adsorption purification stage:

[0046] The diameters of the adsorption columns T1 and T2 are 80 mm, and the length-to-diameter ratio is 8; they are filled with 4A molecular sieves (particle size: 12 mesh). During the adsorption purification process, the raw material is first passed through the adsorption columns for cleaning at a speed of 5 BV / h in the forward direction for 3 BV, and then the adsorbed crude product is collected.

[0047] Among them, 4A molecular sieve needs to be added to hydrochloric acid solution and heated to boiling for treatment before filling. The concentration of hydrochloric acid used is shown in Table 1, the boiling time is 4h, and the volume ratio of hydrochloric acid solution to molecular sieve is 3.

[0048] Conditions in the rectification and purification stage:

[0049] The diameter of rectification column T3 is 120mm, the packing is ring, 8 plates are set in stripping section T31, 6 plates are set in rectifying section T32, and 8 plates are set in fractionating section T33. The crude product collected by adsorption is introduced into rectification column T3, the feeding speed is controlled at 2L / min, and the flow rate of N2 introduced into still kettle T30 is controlled at 0.8L / min.

[0050] Table 1 shows the data of purified butyl carbitol acetate after treating molecular sieve with hydrochloric acid of different concentrations in the adsorption stage.

[0051] Table 1:

[0052]

[0053] As can be seen from Table 1, after the raw material of butyl carbitol acetate is adsorbed by molecular sieve treated with 2-8% hydrochloric acid, the purity of the collected crude product has been improved; while after being adsorbed by molecular sieve treated with 10-12% hydrochloric acid, the purity of the collected crude product has decreased instead. This is because molecular sieve is mainly composed of basic oxides such as Na2O, SiO2, and Al2O3, and the basic raw materials in the production process of molecular sieve include: silicon source, aluminum source, metal ions, alkali, other mineralizing agents and water. There will be residual alkali retained in it during the production process. Acid treatment can remove the residual alkali in it, while too high a concentration will cause residual acid in the molecular sieve, which will lead to the decomposition of the main components and the decrease of the purity of the crude product. It is worth mentioning that the content of alkali in different molecular sieves is different. Therefore, different molecular sieves will have different results with the same concentration of hydrochloric acid.

[0054] Table 2 shows the data of purified butyl carbitol acetate at different vacuum degrees in the rectification stage.

[0055] Table 2:

[0056] Experimental content Raw materials Experimental results Atmospheric distillation 98.63％ 96.77％ Vacuum distillation at 1.0 KPa 98.63％ 99.24％ Vacuum distillation at 5.0 KPa 98.63％ 99.23％ Vacuum distillation at 10.0 KPa 98.63％ 98.93％ Vacuum distillation at 15.0 KPa 98.63％ 98.21％

[0057] As can be seen from Table 2, under vacuum rectification at 1.0-10.0KPa, electronic-grade butyl carbitol acetate is obtained. While under normal pressure or insufficient vacuum, the boiling temperature during rectification is too high, and butyl carbitol acetate will decompose by heating, resulting in the decomposition of some main components. Therefore, the product purity decreases instead.

[0058] Application Example 2

[0059] This example is used to illustrate the purification of butyl carbitol acetate using the system of Example 1. The purification process is as follows:

[0060] Conditions for the adsorption purification stage:

[0061] The diameters of adsorption columns T1 and T2 are 80 mm, and the length-diameter ratio is 8; 5A molecular sieve (particle size: 12 mesh) is used for filling. During the adsorption purification process, the raw material is first passed through the adsorption column in the forward direction at a speed of 5 BV / h for cleaning 3 BV, and then the crude product after adsorption is collected.

[0062] Among them, the 5A molecular sieve needs to be added to the hydrochloric acid solution and heated and boiled before filling. The different concentrations of hydrochloric acid used are shown in Table 3, the boiling time is 4 h, and the volume ratio of the hydrochloric acid solution to the molecular sieve is 3.

[0063] The conditions for the rectification purification stage are the same as those in Application Example 1.

[0064] Table 3 shows the data of purifying butyl carbitol acetate after treating the molecular sieve with hydrochloric acid of different concentrations in the adsorption stage.

[0065] Table 3:

[0066] Experimental content (25 °C) Raw materials Experimental results 5A molecular sieve (hydrochloric acid concentration 2%) 96.0％ 96.70％ 5A molecular sieve (hydrochloric acid concentration 4%) 96.0％ 97.32％ 5A molecular sieve (hydrochloric acid concentration 6%) 96.0％ 97.12％ 5A molecular sieve (hydrochloric acid concentration 8%) 96.0％ 96.71％ 5A molecular sieve (hydrochloric acid concentration 10%) 96.0％ 95.12％ 5A molecular sieve (hydrochloric acid concentration 12%) 96.0％ 93.06％

[0067] Table 4 shows the data of purifying butyl carbitol acetate in the rectification stage.

[0068] Table 4:

[0069] Experimental content Raw materials Experimental results Atmospheric distillation 97.32％ 95.21％ Vacuum distillation at 1.0 KPa 97.32％ 98.96％ Vacuum distillation at 5.0 KPa 97.32％ 98.77％ Vacuum distillation at 10.0 KPa 97.32％ 98.69％ Vacuum distillation at 15.0 KPa 97.32％ 97.86％

[0070] Application Example 3

[0071] This example is used to illustrate the purification of butyl carbitol acetate using the system of Example 1. The purification process is as follows:

[0072] Conditions for the adsorption purification stage:

[0073] The diameters of adsorption columns T1 and T2 are 80 mm, and the length-diameter ratio is 8; 10X molecular sieve (particle size: 12 mesh) is used for filling. During the adsorption purification process, the raw material is first passed through the adsorption column in the forward direction at a speed of 5 BV / h for cleaning 3 BV, and then the crude product after adsorption is collected.

[0074] Among them, the 10X molecular sieve needs to be added to the hydrochloric acid solution and heated and boiled before filling. The concentration of hydrochloric acid used is shown in Table 5, the boiling time is 4 h, and the volume ratio of the hydrochloric acid solution to the molecular sieve is 3.

[0075] The conditions for the rectification purification stage are the same as those in Application Example 1.

[0076] Table 5 shows the data of purifying butyl carbitol acetate after treating molecular sieve with hydrochloric acid of different concentrations in the adsorption stage.

[0077] Table 5:

[0078] Experimental content (25 °C) Raw materials Experimental results 10X molecular sieve (hydrochloric acid concentration 2%) 96.0％ 96.02％ 10X molecular sieve (hydrochloric acid concentration 4%) 96.0％ 96.30％ 10X molecular sieve (hydrochloric acid concentration 6%) 96.0％ 96.72％ 10X molecular sieve (hydrochloric acid concentration 8%) 96.0％ 97.44％ 10X molecular sieve (hydrochloric acid concentration 10%) 96.0％ 96.11％ 10X molecular sieve (hydrochloric acid concentration 12%) 96.0％ 94.93％

[0079] Table 6 shows the data of purifying butyl carbitol acetate in the rectification stage.

[0080] Table 6:

[0081] Experimental content Raw materials Experimental results Atmospheric distillation 97.44％ 95.44％ Vacuum distillation at 1.0 KPa 97.44％ 98.99％ Vacuum distillation at 5.0 KPa 97.44％ 98.94％ Vacuum distillation at 10.0 KPa 97.44％ 98.02％ Vacuum distillation at 15.0 KPa 97.44％ 97.33％

[0082] Application Example 4

[0083] This example is used to illustrate the purification of butyl carbitol acetate using the system of Example 1. The purification process is as follows:

[0084] Conditions in the adsorption purification stage:

[0085] The diameters of adsorption columns T1 and T2 are 80 mm, and the length-diameter ratio is 8; 13X molecular sieve (particle size: 12 mesh) is used for filling. During the adsorption purification process, the raw material is first passed through the adsorption column in the forward direction at a speed of 5 BV / h to wash 3 BV, and then the crude product after adsorption is collected.

[0086] Before filling the 13X molecular sieve, it needs to be added to the hydrochloric acid solution and heated to boiling for treatment. The hydrochloric acid concentration used is shown in Table 7, the boiling time is 4 h, and the volume ratio of the hydrochloric acid solution to the molecular sieve is 3.

[0087] The conditions in the rectification purification stage are the same as those in Application Example 1.

[0088] Table 7 shows the data of purifying butyl carbitol acetate after treating molecular sieve with hydrochloric acid of different concentrations in the adsorption stage.

[0089] Table 7:

[0090] Experimental content (25 °C) Raw materials Experimental results 13X molecular sieve (hydrochloric acid concentration 2%) 96.0％ 96.20％ 13X molecular sieve (hydrochloric acid concentration 4%) 96.0％ 98.08％ 13X molecular sieve (hydrochloric acid concentration 6%) 96.0％ 98.55％ 13X molecular sieve (hydrochloric acid concentration 8%) 96.0％ 97.62％ 13X molecular sieve (hydrochloric acid concentration 10%) 96.0％ 97.31％ 13X molecular sieve (hydrochloric acid concentration 12%) 96.0％ 95.00％

[0091] Table 8 shows the data of purifying butyl carbitol acetate in the rectification stage.

[0092] Table 8:

[0093] Experimental content Raw materials Experimental results Atmospheric distillation 98.55％ 96.44％ Vacuum distillation at 1.0 KPa 98.55％ 98.99％ Vacuum distillation at 5.0 KPa 98.55％ 98.87％ Vacuum distillation at 10.0 KPa 98.55％ 98.66％ Vacuum distillation at 15.0 KPa 98.55％ 97.89％

[0094] Application Example 5

[0095] This example is used to illustrate the purification of butyl carbitol acetate using the system of Example 1. The purification process is as follows:

[0096] Conditions in the adsorption purification stage:

[0097] The diameters of adsorption columns T1 and T2 are 80 mm, and the length-diameter ratio is 8; they are filled with ZSM-5 molecular sieves (particle size: 12 mesh). During the adsorption and purification process, the raw material is first passed through the adsorption columns in the forward direction at a speed of 5 BV / h to wash 3 BV, and then the crude product after adsorption is collected.

[0098] Before filling, the ZSM-5 molecular sieves need to be added to a hydrochloric acid solution and heated to boiling for treatment. The hydrochloric acid concentration used is shown in Table 9, the boiling time is 4 h, and the volume ratio of the hydrochloric acid solution to the volume of the molecular sieves is 3.

[0099] The conditions in the rectification and purification stage are the same as those in Application Example 1.

[0100] Table 9 shows the data of purifying butyl carbitol acetate after treating the molecular sieves with hydrochloric acid at different concentrations in the adsorption stage.

[0101] Table 9:

[0102] Experimental content (25 °C) Raw materials Experimental results ZSM-5 molecular sieve (hydrochloric acid concentration 2%) 96.0％ 94.23％ ZSM-5 molecular sieve (hydrochloric acid concentration 4%) 96.0％ 95.34％ ZSM-5 molecular sieve (hydrochloric acid concentration 6%) 96.0％ 96.70％ ZSM-5 molecular sieve (hydrochloric acid concentration 8%) 96.0％ 95.40％ ZSM-5 molecular sieve (hydrochloric acid concentration 10%) 96.0％ 94.12％ ZSM-5 molecular sieve (hydrochloric acid concentration 12%) 96.0％ 93.50％

[0103] Table 10 shows the data of purifying butyl carbitol acetate in the rectification stage.

[0104] Table 10:

[0105]

[0106]

[0107] Application Example 6

[0108] This example is used to illustrate the purification of butyl carbitol acetate using the system of Example 1. The purification process is as follows:

[0109] Conditions in the adsorption and purification stage:

[0110] The diameters of adsorption columns T1 and T2 are 80 mm, and the length-diameter ratio is 8; they are filled with high-silica Y molecular sieves (particle size: 12 mesh). During the adsorption and purification process, the raw material is first passed through the adsorption columns in the forward direction at a speed of 5 BV / h to wash 3 BV, and then the crude product after adsorption is collected.

[0111] Before filling, the high-silica Y molecular sieves need to be added to a hydrochloric acid solution and heated to boiling for treatment. The hydrochloric acid concentration used is shown in Table 11, the boiling time is 4 h, and the volume ratio of the hydrochloric acid solution to the volume of the molecular sieves is 3.

[0112] The conditions in the rectification and purification stage are the same as those in Application Example 1.

[0113] Table 11 shows the data of purifying butyl carbitol acetate after treating the molecular sieves with hydrochloric acid at different concentrations in the adsorption stage.

[0114] Table 11:

[0115] Experimental content (25 °C) Raw materials Experimental results High-silica Y molecular sieve (hydrochloric acid concentration 2%) 96.0％ 96.02％ High-silica Y molecular sieve (hydrochloric acid concentration 4%) 96.0％ 96.31％ High-silica Y molecular sieve (hydrochloric acid concentration 6%) 96.0％ 96.70％ High-silica Y molecular sieve (hydrochloric acid concentration 8%) 96.0％ 97.41％ High-silica Y molecular sieve (hydrochloric acid concentration 10%) 96.0％ 96.12％ High-silica Y molecular sieve (hydrochloric acid concentration 12%) 96.0％ 94.91％

[0116] Table 12 shows the data of purifying butyl carbitol acetate in the rectification stage.

[0117] Table 12:

[0118] Experimental content Raw materials Experimental results Atmospheric distillation 97.41％ 95.64％ Vacuum distillation at 1.0 KPa 97.41％ 98.68％ Vacuum distillation at 5.0 KPa 97.41％ 98.54％ Vacuum distillation at 10.0 KPa 97.41％ 98.21％ Vacuum distillation at 15.0 KPa 97.41％ 97.56％

[0119] Application Example 7

[0120] This example is used to illustrate the purification of butyl carbitol acetate using the system of Example 1. The purification process is as follows:

[0121] Conditions in the adsorption purification stage:

[0122] The diameters of adsorption columns T1 and T2 are 80 mm, and the length-diameter ratio is 8; different molecular sieves (particle size: 12 mesh) are used for filling. During the adsorption purification process, the raw material is first passed through the adsorption column forward at a speed of 5 BV / h to wash 3 BV, and then the crude product after adsorption is collected.

[0123] Before filling the molecular sieve, it needs to be added to the hydrochloric acid solution and heated and boiled. The hydrochloric acid concentration used is shown in Table 13, the boiling time is 4 h, and the volume ratio of the hydrochloric acid solution to the molecular sieve is 3.

[0124] The conditions in the rectification purification stage are the same as those in Application Example 1.

[0125] Table 13 shows the data of purifying butyl carbitol acetate after combining molecular sieves treated with different concentrations of hydrochloric acid in the adsorption stage.

[0126] Table 13:

[0127] Experimental content (25 °C) Raw materials Experimental results 4A (4% hydrochloric acid) + 13X (4% hydrochloric acid) 96％ 98.76％ 5A molecular sieve (4% hydrochloric acid) + 10X molecular sieve (6% hydrochloric acid) 96％ 97.88％ ZSM-5 molecular sieve (6% hydrochloric acid) + high-silica Y molecular sieve (8% hydrochloric acid) 96％ 96.65％

[0128] Table 14 shows the data of purifying butyl carbitol acetate in the rectification stage.

[0129] Table 14:

[0130] Experimental content Raw materials Experimental results Atmospheric distillation 98.76％ 96.56％ Vacuum distillation at 1.0 KPa 98.76％ 99.88％ Vacuum distillation at 5.0 KPa 98.76％ 99.86％ Vacuum distillation at 10.0 KPa 98.76％ 99.21％ Vacuum distillation at 15.0 KPa 98.76％ 98.88％

[0131] Application Example 8

[0132] This example is used to illustrate the purification of butyl carbitol acetate using the system of Example 2. The purification process is as follows:

[0133] Conditions in the adsorption purification stage:

[0134] The diameters of adsorption columns T1 and T2 are 80 mm, and the length-diameter ratio is 8. The temperature of cold trap D1 is controlled as shown in Table 15. 4A molecular sieve and 13X molecular sieve (particle size: 12 mesh) are used for filling respectively. During the adsorption and purification process, the raw material is first passed through the adsorption column in the forward direction at a speed of 5 BV / h to wash 3 BV, and then the crude product after adsorption is collected.

[0135] Before filling the molecular sieve, it needs to be added to the hydrochloric acid solution and heated and boiled. The hydrochloric acid concentration used is shown in Table 15. The boiling time is 4 h, and the volume ratio of the hydrochloric acid solution to the molecular sieve is 3.

[0136] The conditions in the rectification and purification stage are the same as those in Application Example 1.

[0137] Table 15 shows the data of purifying butyl carbitol acetate after combining molecular sieves treated with hydrochloric acid at different concentrations in the adsorption stage.

[0138] Table 15:

[0139] Experimental content Raw materials Experimental results 4A (4% hydrochloric acid) + 13X (4% hydrochloric acid) 5 °C 96％ 98.84％ 4A (4% hydrochloric acid) + 13X (4% hydrochloric acid) 0°C 96％ 98.93％ 4A (4% hydrochloric acid) + 13X (4% hydrochloric acid) -5°C 96％ 98.80％ 4A (4% hydrochloric acid) + 13X (4% hydrochloric acid) -10°C 96％ 98.88％

[0140] Table 16 shows the data of purifying butyl carbitol acetate at different vacuum degrees in the rectification stage.

[0141] Table 16:

[0142] Experimental content Raw materials Experimental results Atmospheric distillation 98.93％ 95.21％ Vacuum distillation at 1.0 KPa 98.93％ 99.93％ Vacuum distillation at 5.0 KPa 98.93％ 99.92％ Vacuum distillation at 10.0 KPa 98.93％ 99.22％ Vacuum distillation at 15.0 KPa 98.93％ 98.33％

[0143] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited thereto. Within the technical concept scope of the present invention, various simple modifications can be made to the technical solutions of the present invention, including any other suitable combination of each technical feature. These simple modifications and combinations should also be regarded as the content disclosed by the present invention and fall within the protection scope of the present invention.

Claims

1. A system for purifying butyl carbitol acetate, comprising an adsorption device and a rectification device. The adsorption device includes an adsorption column and an adsorbent filled in the adsorption column; the rectification device includes a rectification tower and a vacuum pump connected to the top of the rectification tower.

2. The system for purifying butyl carbitol acetate according to claim 1, wherein The adsorbent is selected from at least one of 4A, 5A, 10X, 13X, ZSM-5, and high-silica Y molecular sieve; preferably, the particle size of the adsorbent is 4 to 20 mesh.

3. The system for purifying butyl carbitol acetate according to claim 1, wherein The adsorbent needs to be pretreated before being filled into the adsorption column. The pretreatment method is: putting the adsorbent into an acid solution and boiling it for 2 to 6 hours; preferably, the volume of the added acid solution is 1 to 4 times the volume of the adsorbent.

4. The system for purifying butyl carbitol acetate according to claim 3, characterized in that, The acid is selected from one of hydrochloric acid, nitric acid, formic acid, and acetic acid; the mass concentration of the acid solution is 1 to 11%, preferably 2 to 9%, and particularly preferably 3 to 8%.

5. The system for purifying butyl carbitol acetate according to claim 1, wherein The diameter of the adsorption column is 20 to 200 mm, and the length-diameter ratio is 4 to 10.

6. The system for purifying butyl carbitol acetate according to claim 1, wherein The adsorption device includes at least two adsorption columns connected in series in sequence. The adsorbents filled in different adsorption columns can be the same or different; Preferably, the adsorbents filled in different adsorption columns are different; Preferably, the adsorption device further includes a cold trap, which is arranged between the outlet of the raw material storage tank and the inlet of the first adsorption column; More preferably, the temperature of the cold trap is -10 to 5°C, and more preferably -5 to 0°C.

7. The system for purifying butyl carbitol acetate according to claim 1, characterized in that, The rectification tower includes a tower kettle, a stripping section, a rectification section, and a fractionation section from bottom to top; the stripping section includes 2 to 14 trays; the rectification section includes 2 to 10 trays; the fractionation section includes 6 to 10 trays; the crude product inlet is arranged at the junction of the stripping section and the rectification section; the product outlet is arranged at the junction of the rectification section and the fractionation section; an N2 inlet is provided on the tower kettle; Preferably, a filler is provided in the rectification tower, and the filler is selected from one or a combination of Raschig rings, Pall rings, θ rings, arc saddle rings, and rectangular saddle rings; Preferably, the diameter of the filler is 1 / 15 to 1 / 5 of the tower diameter of the rectification tower; Preferably, the materials of the rectification tower and the filler are selected from one or a combination of stainless steel, quartz, glass, and polytetrafluoroethylene.

8. The system for purifying butyl carbitol acetate according to claim 1, wherein, The rectification device further includes a cooling device. One end of the cooling device is connected to the top of the rectification tower, and the other end is connected to the vacuum pump; a waste liquid outlet is provided on one side of the condenser close to the vacuum pump, and the waste liquid outlet is connected to a waste liquid collection tank.

9. A method for purifying butyl carbitol acetate, which is purified by the system according to claims 1 to 8.

10. The method according to claim 9, characterized in that, The method includes the following steps: The crude butyl carbitol acetate first passes through the adsorption device and then is sent into the rectification device for rectification to obtain electronic-grade butyl carbitol acetate; Among them, the vacuum degree during rectification is 0.5 to 15.0 KPa, preferably 1 to 10 KPa, and more preferably 1 to 9 KPa.

Images