Device and method for continuous and synchronous graded hydrolysis of acylation reaction liquid

Abstract

The present invention provides an apparatus and method for continuous and synchronous graded hydrolysis of an acylation reaction liquid. The acylation reaction liquid and an aqueous phase are first mixed in a cryogenic cooler and then passed through a primary microchannel reactor for primary hydrolysis. After the primary hydrolyzed liquid is separated in a separator, the oil phase is again passed through a secondary microchannel reactor for secondary hydrolysis. After the secondary hydrolyzed liquid is separated in a separator, the secondary oil phase is further separated from the emulsified water by a coalescing separator. The method of the present invention utilizes graded hydrolysis to treat the acylation reaction liquid. After the primary hydrolysis, aluminum resources can be recovered. After the secondary hydrolysis, a Fenton-coupled electrocatalytic oxidation process is used to meet wastewater discharge standards. The apparatus of the present invention utilizes a one-in-one standby separation tank to achieve stable and continuous synchronous hydrolysis of the acylation reaction liquid. The apparatus of the present invention reduces the emulsified water content in the nitrobenzene oil phase by providing a separator and coalescing separator.

Description

Technical Field

[0001] The invention relates to the technical field of hydrolysis treatment of acylation reaction liquid, and in particular to a device and method for continuously and synchronously hydrolyzing acylation reaction liquid by graded steps. Background Art

[0002] 2,6-Naphthalene dicarboxylic acid is a key monomer for the synthesis of high-performance polynaphthalene esters, polyurethanes, and liquid crystal polyester resins. Polyethylene naphthalate (PEN), produced by the reaction of 2,6-naphthalene dicarboxylic acid with ethylene glycol, exhibits superior physical and chemical properties to the currently widely used polyethylene terephthalate (PET). PEN has broad application prospects in fibers, films, packaging containers, and electronic components.

[0003] 2-Methyl-6-acylaphthalene is an important raw material for the preparation of 2,6-naphthalenedicarboxylic acid. 2-Methylnaphthalene is widely available, inexpensive, and readily available (coal tar, ethylene tar, and other sources are rich in 2-methylnaphthalene). 2-Methyl-6-acylaphthalene can be prepared through an acylation reaction of 2-methylnaphthalene followed by hydrolysis and purification. After the acylation reaction, the reaction is quenched by hydrolysis, followed by purification through reduced pressure distillation, rectification, and recrystallization to obtain high-purity 2-methyl-6-propionylnaphthalene.

[0004] During hydrolysis quenching, a large amount of water washing agent is required to acylate the oil phase, which will produce strongly acidic aluminum-containing wastewater. The acylation wastewater is highly toxic, strongly acidic (pH <1.0), and has a high COD (8000-15000), making it difficult to treat. At the same time, the acylation wastewater contains a large amount of aluminum resources. Directly treating the wastewater and discharging it wastes resources and pollutes the environment. However, when the amount of water used for direct hydrolysis is large, the concentration of aluminum ions is diluted. When recovering aluminum resources, excess water needs to be evaporated, which will cause energy waste. If only a static method is used to separate nitrobenzene and water, if the equipment structure is too simple, the separation effect will be poor when the emulsification degree of nitrobenzene and water is high, which increases the difficulty of subsequent distillation process treatment. On the other hand, the poor separation effect of the nitrobenzene separator also causes nitrobenzene to be entrained in the separated water. When this part of water enters the nitrobenzene wastewater stripping tower for treatment again, it will greatly reduce the efficiency of the tower, increase the amount of steam used, and increase the energy consumption and operating cost of nitrobenzene wastewater treatment.

[0005] In the prior art, some documents disclose intermittent or semi-continuous hydrolysis schemes, which fail to synchronize the acylation reaction and the hydrolysis reaction. After obtaining the acylation reaction liquid, there is a certain time interval before the hydrolysis reaction is carried out. The acylation reaction liquid cannot be hydrolyzed in time. When left standing, it is easy to undergo a hydrolysis reaction with water in the air, and HCl gas will overflow, polluting the air. In addition, a large amount of heat is released when the acylation reaction liquid contacts water, requiring cooling. Some documents disclose a method for continuous and synchronous hydrolysis of the acylation reaction liquid, in which the hydrolyzed liquid can be directly introduced into a liquid separator for synchronous separation. However, this scheme does not adopt graded hydrolysis, resulting in a relatively large oil-to-water ratio and a low aluminum ion concentration in the aqueous phase, which is not convenient for subsequent recovery of aluminum resources. At the same time, the overall water consumption is high, and the emulsified water content in the obtained oil phase is high. Summary of the Invention

[0006] The object of the present invention is to provide a device and method for continuous and synchronous graded hydrolysis of acylation reaction liquid. The method utilizes a spare storage tank to achieve stable and continuous synchronous hydrolysis of the acylation reaction liquid. The graded hydrolysis method is adopted to facilitate aluminum resource recovery and meet wastewater discharge standards.

[0007] In one embodiment of the present application, a device for continuous and synchronous graded hydrolysis of an acylation reaction liquid is provided, comprising a raw oil tank, a first water storage tank, a second water storage tank, a low-temperature cooling bath, a primary microchannel reactor, a secondary microchannel reactor, a primary liquid separator, a secondary liquid separator, a primary water tank, a primary oil tank, a secondary water tank, a secondary oil tank, and a coalescing separator, wherein the outlet of the raw oil tank and the outlet of the first water storage tank are connected to the inlet of the low-temperature cooling bath via a pipeline, the outlet of the low-temperature cooling bath is connected to the inlet of the primary microchannel reactor, the hydrolysis outlet of the primary microchannel reactor is connected in parallel to the inlets of several primary liquid separators, the primary liquid separator is provided with a water outlet and an oil outlet, the water outlet of the primary liquid separator is connected to the inlet of the primary water tank, and the oil outlet of the primary liquid separator is connected to the inlet of the primary oil tank;

[0008] The outlet of the first oil tank and the outlet of the second water storage tank are connected to the inlet of the secondary microchannel reactor through a pipeline. The hydrolysis outlet of the secondary microchannel reactor is connected in parallel to the inlets of several secondary liquid separation tanks. The secondary liquid separation tank is provided with a water outlet and an oil outlet. The water outlet of the secondary liquid separation tank is connected to the inlet of the secondary water tank, the oil outlet of the secondary liquid separation tank is connected to the inlet of the secondary oil tank, and the outlet of the secondary oil tank is connected to the inlet of the coalescing separator. The coalescing separator is provided with a water phase outlet and an oil phase outlet.

[0009] In some embodiments, there are two first-level liquid separating tanks, namely liquid separating tank No. 1 and liquid separating tank No. 2. The pipeline of the hydrolysis outlet of the first-level microchannel reactor is connected to the inlet of liquid separating tank No. 1 and the inlet of liquid separating tank No. 2 through a three-way valve. The bottom end of liquid separating tank No. 1 and the bottom end of liquid separating tank No. 2 are both connected with three-way valves. One branch of the three-way valve of liquid separating tank No. 1 is connected to the inlet of the first-level water tank, and the other branch of the three-way valve of liquid separating tank No. 1 is connected to the inlet of the first-level oil tank. One branch of the three-way valve of liquid separating tank No. 2 is connected to the inlet of the first-level water tank, and the other branch of the three-way valve of liquid separating tank No. 2 is connected to the inlet of the first-level oil tank.

[0010] In some embodiments, there are two secondary liquid separating tanks, namely liquid separating tank No. 3 and liquid separating tank No. 4. The pipeline of the hydrolysis outlet of the secondary microchannel reactor is connected to the inlet of liquid separating tank No. 3 and the inlet of liquid separating tank No. 4 through a three-way valve. The bottom end of liquid separating tank No. 3 and the bottom end of liquid separating tank No. 4 are both connected to three-way valves. One branch of the three-way valve of liquid separating tank No. 3 is connected to the inlet of the secondary water tank, and the other branch of the three-way valve of liquid separating tank No. 3 is connected to the inlet of the secondary oil tank. One branch of the three-way valve of liquid separating tank No. 4 is connected to the inlet of the secondary water tank, and the other branch of the three-way valve of liquid separating tank No. 4 is connected to the inlet of the secondary oil tank.

[0011] In some embodiments, the No. 1 liquid separation tank, the No. 2 liquid separation tank, the No. 3 liquid separation tank and the No. 4 liquid separation tank are all connected to a vacuum pump for extracting waste gas, and the outlet of the vacuum pump is connected to the alkali liquid tank.

[0012] Another embodiment of the present application provides a method for continuously and synchronously hydrolyzing an acylation reaction solution by graded hydrolysis, using the above-mentioned apparatus for continuously and synchronously hydrolyzing an acylation reaction solution by graded hydrolysis, comprising the following steps:

[0013] S1, open the first water storage tank and the raw oil tank storing the acylation reaction liquid, match the flow rate of the water phase and the oil phase in a 1:1 ratio, mix them in a low-temperature cooling bath, and then enter the first microchannel reactor. After ultrasonic vibration for a period of time, the mixed liquid flows out of the hydrolysis outlet of the first microchannel reactor and enters the first separator tank;

[0014] S2, when the No. 1 separatory tank reaches the set liquid level, the hydrolysis outlet is switched to the No. 2 separatory tank by using the three-way valve, and the mixed liquid in the No. 1 separatory tank is heated and stirred at the same time. After the oil and water in the No. 1 separatory tank are allowed to stand and separate, the three-way valve at the bottom of the No. 1 separatory tank is opened, and the oil phase at the lower layer in the No. 1 separatory tank is first collected into the first-level oil tank. After the oil phase is collected, the pipeline of the three-way valve at the bottom of the No. 1 separatory tank is switched, and the remaining water phase in the No. 1 separatory tank is collected into the first-level water tank. After the water phase is collected, the three-way valve of the No. 1 separatory tank is closed, and the No. 1 separatory tank is ready for use;

[0015] S3, when the No. 2 separatory tank reaches the set liquid level, the hydrolysis outlet is switched to the No. 1 separatory tank by using the three-way valve, and the mixed liquid in the No. 2 separatory tank is heated and stirred at the same time. After the oil and water in the No. 2 separatory tank are allowed to stand and stratify, the three-way valve at the bottom of the No. 2 separatory tank is opened, and the oil phase located at the lower layer in the No. 2 separatory tank is first collected into the primary oil tank. After the oil phase is collected, the pipeline of the three-way valve at the bottom of the No. 2 separatory tank is switched, and the remaining water phase in the No. 2 separatory tank is collected into the primary water tank. After the water phase is collected, the three-way valve of the No. 2 separatory tank is closed, and the No. 2 separatory tank is ready for use. Steps S2 and S3 are repeated several times until the raw material oil tank is completely emptied;

[0016] S4, when the first-level oil tank reaches the set liquid level, the first-level oil tank and the second water storage tank are opened, the flow rate of the water phase and the oil phase is matched in a ratio of 2:1, and the mixed liquid enters the second-level microchannel reactor and is ultrasonically vibrated for a period of time. The mixed liquid flows out of the hydrolysis outlet of the second-level microchannel reactor and enters the third separation tank;

[0017] S5, when the No. 3 separator tank reaches the set liquid level, the hydrolysis outlet is switched to the No. 4 separator tank by using the three-way valve, and the mixed liquid in the No. 3 separator tank is heated and stirred at the same time. After the oil and water in the No. 3 separator tank are allowed to stand and separate, the three-way valve at the bottom of the No. 3 separator tank is opened, and the oil phase at the lower layer in the No. 3 separator tank is first collected into the secondary oil tank. After the oil phase is collected, the pipeline of the three-way valve at the bottom of the No. 3 separator tank is switched, and the remaining water phase in the No. 3 separator tank is collected into the secondary water tank. After the water phase is collected, the three-way valve of the No. 3 separator tank is closed, and the No. 3 separator tank is ready for use;

[0018] S6, when the No. 4 separatory tank reaches the set liquid level, the hydrolysis outlet is switched to the No. 3 separatory tank by using the three-way valve, and the mixed liquid in the No. 4 separatory tank is heated and stirred at the same time. After the oil and water in the No. 4 separatory tank are allowed to stand and separate, the three-way valve at the bottom of the No. 4 separatory tank is opened, and the oil phase in the lower layer of the No. 4 separatory tank is first collected into the secondary oil tank. After the oil phase is collected, the pipeline of the three-way valve at the bottom of the No. 4 separatory tank is switched to collect the remaining water phase in the No. 4 separatory tank into the secondary water tank. After the water phase is collected, the three-way valve of the No. 4 separatory tank is closed, and the No. 4 separatory tank is ready for use. Steps S5 and S6 are repeated several times until the primary oil tank is completely emptied;

[0019] S7, the secondary oil tank passes the oil phase into the coalescing separator to further remove the emulsified water.

[0020] The method of the present invention is characterized by being continuous, efficient and stable. The primary hydrolysis water is rich in aluminum ions and chloride ions, which facilitates the recovery of aluminum resources. The secondary hydrolysis water has low treatment difficulty and can meet the wastewater discharge standards through the Fenton-coupled electrocatalytic process. At the same time, the emulsified water content in the oil phase is reduced through treatment in a liquid-liquid separator and separation in a rear-end coalescing separator.

[0021] In some embodiments, the water in the primary water tank is stripped of organic matter by steam, decolorized by activated carbon, and then polymerized by an alkalizing agent to obtain liquid PAC.

[0022] In some embodiments, the water in the secondary water tank, the stripped water in the primary water tank, and the water separated by the coalescing separator are mixed and filtered first, and then subjected to Fenton oxidation and electrocatalytic oxidation to treat organic matter to reduce COD to below 500.

[0023] In some embodiments, the temperature inside the primary microchannel reactor and the secondary microchannel reactor is 30-35°C.

[0024] In some embodiments, the heating temperature in the No. 1 separating tank, the No. 2 separating tank, the No. 3 separating tank, and the No. 4 separating tank is 60° C., the stirring speed is 200 r / min, and the stirring time is 30 min.

[0025] In some embodiments, the temperature of the cryogenic cooling bath is 0°C.

[0026] The beneficial effects of the present invention are:

[0027] (1) The method of the present invention adopts a graded hydrolysis method to treat the acylation reaction liquid. After the primary hydrolysis, aluminum resources can be recovered. After the secondary hydrolysis, the Fenton-coupled electrocatalytic oxidation process is used to meet the wastewater discharge standards.

[0028] (2) The separatory tanks in the device of the present invention are operated in a one-on-one standby mode to achieve stable and continuous synchronous hydrolysis of the acylation reaction liquid;

[0029] (3) In the device of the present invention, the emulsified water content in the nitrobenzene oil phase is reduced by providing a liquid separator and a coalescing separator. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings.

[0031] in:

[0032] Figure 1 Schematic diagram of the structure of the device for continuous synchronous graded hydrolysis of acylation reaction liquid in the embodiment of the present application;

[0033] Reference numerals:

[0034] 1-Raw material oil tank; 2-First water storage tank; 3-First microchannel reactor; 4-No. 1 liquid separation tank; 5-No. 2 liquid separation tank; 6-First water tank; 7-First oil tank; 8-Second water storage tank; 9-Second microchannel reactor; 10-No. 3 liquid separation tank; 11-No. 4 liquid separation tank; 12-Second oil tank; 13-Second water tank; 14-Agglomeration separator. DETAILED DESCRIPTION

[0035] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0036] The following describes an apparatus and method for continuous synchronous graded hydrolysis of an acylation reaction solution according to an embodiment of the present invention with reference to the accompanying drawings.

[0037] like Figure 1 As shown, an embodiment of the present application provides a device for continuous and synchronous graded hydrolysis of an acylation reaction liquid, comprising a raw oil tank 1, a first water storage tank 2, a second water storage tank 8, a low-temperature cooling bath (not shown in the figure), a primary microchannel reactor 3, a secondary microchannel reactor 9, a primary liquid separator, a secondary liquid separator, a primary water tank 6, a primary oil tank 7, a secondary water tank 13, a secondary oil tank 12 and a coalescing separator 14, the outlet of the raw oil tank 1 and the outlet of the first water storage tank 2 are commonly connected to the inlet of the low-temperature cooling bath through a pipeline, the outlet of the low-temperature cooling bath is connected to the inlet of the primary microchannel reactor 3, the hydrolysis outlet of the primary microchannel reactor 3 is connected in parallel to the inlets of several primary liquid separators, the primary liquid separator is provided with a water outlet and an oil outlet, the water outlet of the primary liquid separator is connected to the inlet of the primary water tank 6, and the oil outlet of the primary liquid separator is connected to the inlet of the primary oil tank 7;

[0038] The outlet of the first-level oil tank 7 and the outlet of the second water storage tank 8 are connected to the inlet of the secondary microchannel reactor 9 through a pipeline. The hydrolysis outlet of the secondary microchannel reactor 9 is connected in parallel to the inlets of several secondary liquid separation tanks. The secondary liquid separation tank is provided with a water outlet and an oil outlet. The water outlet of the secondary liquid separation tank is connected to the inlet of the secondary water tank 13, and the oil outlet of the secondary liquid separation tank is connected to the inlet of the secondary oil tank 12. The outlet of the secondary oil tank 12 is connected to the inlet of the coalescing separator 14. The coalescing separator 14 is provided with a water phase outlet and an oil phase outlet.

[0039] In some specific embodiments, there are two first-level liquid separating tanks, namely, liquid separating tank No. 1 4 and liquid separating tank No. 2 5. The pipeline of the hydrolysis outlet of the first-level microchannel reactor 3 is connected to the inlet of liquid separating tank No. 1 4 and the inlet of liquid separating tank No. 2 5 through a three-way valve. The bottom end of liquid separating tank No. 1 4 and the bottom end of liquid separating tank No. 2 5 are both connected with three-way valves. One branch of the three-way valve of liquid separating tank No. 1 4 is connected to the inlet of the first-level water tank 6, and the other branch of the three-way valve of liquid separating tank No. 1 4 is connected to the inlet of the first-level oil tank 7. One branch of the three-way valve of liquid separating tank No. 2 5 is connected to the inlet of the first-level water tank 6, and the other branch of the three-way valve of liquid separating tank No. 2 5 is connected to the inlet of the first-level oil tank 7.

[0040] In some specific embodiments, there are two secondary liquid separating tanks, namely liquid separating tank No. 3 10 and liquid separating tank No. 4 11. The pipeline of the hydrolysis outlet of the secondary microchannel reactor 9 is connected to the inlet of liquid separating tank No. 3 10 and the inlet of liquid separating tank No. 4 11 through a three-way valve. The bottom end of liquid separating tank No. 3 10 and the bottom end of liquid separating tank No. 4 11 are both connected to three-way valves. One branch of the three-way valve of liquid separating tank No. 3 10 is connected to the inlet of the secondary water tank 13, and the other branch of the three-way valve of liquid separating tank No. 3 10 is connected to the inlet of the secondary oil tank 12. One branch of the three-way valve of liquid separating tank No. 4 11 is connected to the inlet of the secondary water tank 13, and the other branch of the three-way valve of liquid separating tank No. 4 11 is connected to the inlet of the secondary oil tank 12.

[0041] In some specific embodiments, the No. 1 separating tank 4, the No. 2 separating tank 5, the No. 3 separating tank 10 and the No. 4 separating tank 11 are all connected with a micro vacuum pump for timely extracting the acidic waste gas during the hydrolysis process. The outlet of the vacuum pump is connected to the alkali liquid tank for acid gas collection to avoid equipment corrosion.

[0042] The No. 1 liquid separation tank 4, the No. 2 liquid separation tank 5, the No. 3 liquid separation tank 10 and the No. 4 liquid separation tank 11 are not only storage tanks, but also play the role of liquid-liquid separation.

[0043] In some specific embodiments, the No. 1 separating tank 4, the No. 2 separating tank 5, the No. 3 separating tank 10 and the No. 4 separating tank 11 are all equipped with a stirring device, a heating device and a gas extraction port, and the gas extraction port is connected to an acid gas extraction pump.

[0044] In some specific embodiments, the outlet pipelines of the raw oil tank 1, the first-level oil tank 7, and the second-level oil tank 12 are all connected to oil injection pumps for providing power for conveying the oil phase, and the outlet pipelines of the first water storage tank 2 and the second water storage tank 8 are all connected to water injection pumps for providing power for conveying the water phase.

[0045] In some specific embodiments, the stirring paddles of the stirring devices in the first, second, third, and fourth separator tanks 4, 5, 10, and 11 are longer, similar to a scraper structure, to accelerate the settling of surface oil and achieve better water-oil separation. The four separator tanks are pre-treated with heating and stirring to accelerate separation and settling.

[0046] In some specific embodiments, the outlet pipes of the first, second, third, and fourth separators 4, 5, 10, and 11 are all connected to a delivery pump to provide power for liquid delivery. In addition to the delivery pump, liquid separation is primarily achieved by gravity level differences within the separators, making the equipment less prone to failure.

[0047] Another embodiment of the present application provides a method for continuously and synchronously hydrolyzing an acylation reaction solution by graded hydrolysis, using the above-mentioned apparatus for continuously and synchronously hydrolyzing an acylation reaction solution by graded hydrolysis, comprising the following steps:

[0048] S1, the first water storage tank 2 stores deionized water (i.e., water phase) for hydrolyzing the acylation reaction liquid, and the raw oil tank 1 stores the acylation reaction liquid to be hydrolyzed, and the acylation reaction liquid is the oil phase. Turn on the water injection pump of the first water storage tank 2, and when the deionized water flows out from the outlet of the first-level microchannel reactor 3, turn on the oil injection pump of the raw oil tank 1, control the flow rate, and match the flow rate of the water phase and the oil phase in a 1:1 ratio. The oil phase and the water phase are mixed in a low-temperature cold bath and then enter the first-level microchannel reactor 3, wherein the temperature of the low-temperature cold bath is 0°C, and the temperature of the microchannel reactor is controlled to be 30-35°C. At the same time, ultrasonic vibration is applied. After a period of time, a turbid light brown liquid flows out from the hydrolysis outlet of the first-level microchannel reactor 3 and enters the No. 1 liquid separation tank 4, and the micro-vacuum pump is turned on;

[0049] S2, when the No. 1 separator 4 reaches the set liquid level, the hydrolysis outlet is switched to the No. 2 separator 5 by using the three-way valve, and the mixed liquid in the No. 1 separator 4 is heated and stirred for 30 minutes, with a stirring speed of 200r / min and a heating temperature of 60°C. After the oil and water in the No. 1 separator 4 are allowed to stand and separate, the three-way valve at the bottom of the No. 1 separator 4 is opened, and the oil phase in the lower layer of the No. 1 separator 4 is first collected into the first-level oil tank 7. After the oil phase is collected, the pipeline of the three-way valve at the bottom of the No. 1 separator 4 is switched, and the remaining water phase in the No. 1 separator 4 is collected into the first-level water tank 6. After the water phase is collected, the three-way valve of the No. 1 separator 4 is closed, and the No. 1 separator 4 is ready for use;

[0050] S3, the functions of No. 2 separator 5 and No. 1 separator 4 are consistent, and the two separators are one open and one standby to ensure that the primary hydrolysis is carried out continuously. When No. 2 separator 5 reaches the set liquid level, the hydrolysis outlet is switched to No. 1 separator 4 by using the three-way valve, and the mixed liquid in No. 2 separator 5 is heated and stirred for 30min at the same time, with a stirring speed of 200r / min and a heating temperature of 60°C. After the oil and water in No. 2 separator 5 are allowed to stand by for stratification, the three-way valve at the bottom of No. 2 separator 5 is opened, and the oil phase in the lower layer of No. 2 separator 5 is first collected into the primary oil tank 7. After the oil phase is collected, the pipeline of the three-way valve at the bottom of No. 2 separator 5 is switched, and the remaining water phase in No. 2 separator 5 is collected into the primary water tank 6. After the water phase is collected, the three-way valve of No. 2 separator 5 is closed, and No. 2 separator 5 is on standby. Repeat steps S2 and S3 several times until the raw material oil tank 1 is completely emptied.

[0051] S4, when the first-level oil tank 7 reaches the set liquid level, the water injection pump of the second water storage tank 8 is turned on. When the deionized water flows out from the outlet of the secondary microchannel reactor 9, the oil injection pump of the first-level oil tank 7 is turned on, and the flow rate is controlled to match the flow rate of the water phase and the oil phase in a ratio of 2:1. The water phase and the oil phase enter the secondary microchannel reactor 9 and are mixed. The mixing temperature is controlled to be 30-35°C. At the same time, ultrasonic oscillation is turned on. After a period of time, the turbid light brown liquid flows out from the hydrolysis outlet of the secondary microchannel reactor 9 and enters the No. 3 liquid separation tank 10. The micro air pump is turned on;

[0052] S5, when the third separator 10 reaches the set liquid level, the hydrolysis outlet is switched to the fourth separator 11 by using the three-way valve, and the mixed liquid in the third separator 10 is heated and stirred for 30 minutes, the stirring speed is 200r / min, the heating temperature is 60°C, and after the oil and water in the third separator 10 are allowed to stand and stratify, the three-way valve at the bottom of the third separator 10 is opened, and the oil phase at the lower layer in the third separator 10 is first collected into the secondary oil tank 12. After the oil phase is collected, the pipeline of the three-way valve at the bottom of the third separator 10 is switched, and the remaining water phase in the third separator 10 is collected into the secondary water tank 13. After the water phase is collected, the three-way valve of the third separator 10 is closed, and the third separator 10 is ready for use;

[0053] S6, the functions of the No. 3 liquid separation tank 10 and the No. 4 liquid separation tank 11 are the same, and the two liquid separation tanks, one in operation and one in standby, ensure that the secondary hydrolysis is carried out continuously. When the fourth separator 11 reaches the set liquid level, the hydrolysis outlet is switched to the third separator 10 by using the three-way valve. At the same time, the mixed liquid in the fourth separator 11 is heated and stirred for 30 minutes, the stirring speed is 200r / min, and the heating temperature is 60°C. After the oil and water in the fourth separator 11 are allowed to stand and stratify, the three-way valve at the bottom of the fourth separator 11 is opened, and the oil phase located at the lower layer in the fourth separator 11 is first collected into the secondary oil tank 12. After the oil phase is collected, the pipeline of the three-way valve at the bottom of the fourth separator 11 is switched, and the remaining water phase in the fourth separator 11 is collected into the secondary water tank 13. After the water phase is collected, the three-way valve of the fourth separator 11 is closed, and the fourth separator 11 is ready for use. Steps S5 and S6 are repeated several times until the primary oil tank 7 is completely emptied.

[0054] S7, the secondary oil tank 12 passes the oil phase into the coalescing separator 14 to further remove the emulsified water. The coalescing separator 14 is used to further separate the emulsified water in the nitrobenzene to facilitate subsequent distillation.

[0055] In some specific embodiments, the water in the primary water tank 6 is stripped of organic matter by steam, then decolorized by activated carbon, and then polymerized by an alkalizing agent to obtain liquid PAC (polyaluminium chloride).

[0056] In some specific embodiments, the water in the secondary water tank 13, the stripped water in the primary water tank 6, and the water separated by the coalescing separator 14 are mixed and first filtered, and then subjected to Fenton oxidation and electrocatalytic oxidation to treat organic matter, reducing the COD to below 500, meeting the park pipe network emission standards.

[0057] The present invention adopts a synchronous hydrolysis reaction, thereby avoiding long-term storage of the acylation reaction solution and reducing overflow and pollution of HCl gas.

[0058] The present invention uses graded hydrolysis to quench the acylation reaction. The wastewater after primary hydrolysis has a high aluminum ion concentration. Organic matter is treated through steam stripping, aluminum resources are recovered, and the wastewater can be used to prepare liquid PAC. The secondary water treatment process is also simplified. The overall water consumption is lower than that of direct hydrolysis. The liquid separation tank uses a liquid-liquid separator equipped with stirring, heating, and a vacuum port, facilitating rapid oil-water separation. Furthermore, the secondary oil phase is treated in a coalescing separator 14 to further remove emulsified water entrained in the nitrobenzene, facilitating subsequent distillation of the oil phase.

[0059] The present application is further described below through specific examples.

[0060] Example 1

[0061] A method for continuous and synchronous graded hydrolysis of acylation reaction solution, such as Figure 1 As shown, the device for continuously and synchronously hydrolyzing the acylation reaction solution comprises the following steps:

[0062] S1, the first water storage tank 2 stores deionized water (i.e., aqueous phase) for hydrolyzing the acylation reaction liquid, and the raw oil tank 1 stores the acylation reaction liquid to be hydrolyzed, and the acylation reaction liquid is the oil phase. Turn on the water injection pump of the first water storage tank 2, and when the deionized water flows out from the outlet of the first-level microchannel reactor 3, turn on the oil injection pump of the raw oil tank 1, control the flow rate, and match the flow rate of the water phase and the oil phase in a 1:1 ratio. The oil phase and the water phase are mixed in a low-temperature cold bath and then enter the first-level microchannel reactor 3, wherein the temperature of the low-temperature cold bath is 0°C, and the temperature of the microchannel reactor is controlled to 35°C. At the same time, ultrasonic vibration is applied. After a period of time, a turbid light brown liquid flows out from the hydrolysis outlet of the first-level microchannel reactor 3 and enters the No. 1 liquid separation tank 4, and the micro-vacuum pump is turned on;

[0063] S2, when the No. 1 separator 4 reaches the set liquid level, the hydrolysis outlet is switched to the No. 2 separator 5 by using the three-way valve, and the mixed liquid in the No. 1 separator 4 is heated and stirred for 30 minutes, and then allowed to stand for 50 minutes, wherein the stirring speed is 200r / min and the heating temperature is 60°C. After standing, the oil and water in the No. 1 separator 4 are allowed to stand and separate, and the three-way valve at the bottom of the No. 1 separator 4 is opened. The oil phase in the lower layer of the No. 1 separator 4 is first collected into the first-level oil tank 7. After the oil phase is collected, the pipeline of the three-way valve at the bottom of the No. 1 separator 4 is switched to collect the remaining water phase in the No. 1 separator 4 into the first-level water tank 6. After the water phase is collected, the three-way valve of the No. 1 separator 4 is closed and the No. 1 separator 4 is ready for use;

[0064] S3, the functions of No. 2 separator 5 and No. 1 separator 4 are consistent, and the two separators are one open and one standby to ensure that the primary hydrolysis is carried out continuously. When No. 2 separator 5 reaches the set liquid level, the hydrolysis outlet is switched to No. 1 separator 4 by using the three-way valve, and the mixed liquid in No. 2 separator 5 is heated and stirred for 30min, and then allowed to stand for 50min, wherein the stirring speed is 200r / min, and the heating temperature is 60°C. After standing, the oil and water in No. 2 separator 5 are allowed to stand and stratify. The three-way valve at the bottom of No. 2 separator 5 is opened, and the oil phase in the lower layer of No. 2 separator 5 is first collected into the primary oil tank 7. After the oil phase is collected, the pipeline of the three-way valve at the bottom of No. 2 separator 5 is switched, and the remaining water phase in No. 2 separator 5 is collected into the primary water tank 6. After the water phase is collected, the three-way valve of No. 2 separator 5 is closed, and No. 2 separator 5 is on standby. Steps S2 and S3 are repeated several times until the raw material oil tank 1 is completely emptied.

[0065] S4, when the first-level oil tank 7 reaches the set liquid level, the water injection pump of the second water storage tank 8 is turned on. When the deionized water flows out from the outlet of the secondary microchannel reactor 9, the oil injection pump of the first-level oil tank 7 is turned on, and the flow rate is controlled to match the flow rate of the water phase and the oil phase in a ratio of 2:1. The water phase and the oil phase enter the secondary microchannel reactor 9 and are mixed. The mixing temperature is controlled to 35°C, and ultrasonic vibration is turned on at the same time. After a period of time, the turbid light brown liquid flows out from the hydrolysis outlet of the secondary microchannel reactor 9 and enters the No. 3 liquid separation tank 10, and the micro air pump is turned on;

[0066] S5, when the No. 3 separator 10 reaches the set liquid level, the hydrolysis outlet is switched to the No. 4 separator 11 by using the three-way valve, and the mixed liquid in the No. 3 separator 10 is heated and stirred for 30 minutes, and then allowed to stand for 30 minutes, wherein the stirring speed is 200r / min, the heating temperature is 60°C, and the oil and water in the No. 3 separator 10 are allowed to stand by stratification after standing, and the three-way valve at the bottom end of the No. 3 separator 10 is opened. The oil phase in the lower layer of the No. 3 separator 10 is first collected into the secondary oil tank 12. After the oil phase is collected, the pipeline of the three-way valve at the bottom end of the No. 3 separator 10 is switched, and the remaining water phase in the No. 3 separator 10 is collected into the secondary water tank 13. After the water phase is collected, the three-way valve of the No. 3 separator 10 is closed, and the No. 3 separator 10 is ready for use;

[0067] S6, the functions of the No. 3 liquid separation tank 10 and the No. 4 liquid separation tank 11 are the same, and the two liquid separation tanks, one in operation and one in standby, ensure that the secondary hydrolysis is carried out continuously. When the fourth separator 11 reaches the set liquid level, the hydrolysis outlet is switched to the third separator 10 by using the three-way valve, and the mixed liquid in the fourth separator 11 is heated and stirred for 30 minutes, and then allowed to stand for 30 minutes, wherein the stirring speed is 200r / min, and the heating temperature is 60°C. After standing, the oil and water in the fourth separator 11 are allowed to stand and stratify, and the three-way valve at the bottom end of the fourth separator 11 is opened. The oil phase located at the lower layer in the fourth separator 11 is first collected into the secondary oil tank 12. After the oil phase is collected, the pipeline of the three-way valve at the bottom end of the fourth separator 11 is switched, and the remaining water phase in the fourth separator 11 is collected into the secondary water tank 13. After the water phase is collected, the three-way valve of the fourth separator 11 is closed, and the fourth separator 11 is ready for use. Steps S5 and S6 are repeated several times until the primary oil tank 7 is completely emptied;

[0068] S7, the secondary oil tank 12 passes the oil phase into the coalescing separator 14 to further remove the emulsified water to obtain the final oil phase, wherein the final oil phase water content is 2500ppm, the aluminum ion concentration in the primary water is 14%, and the oil phase pH is 6-7.

[0069] Comparative Example 1

[0070] The difference from Example 1 is that the oil phase is not further separated by the rear-end coalescing separator 14, and the water content in the final oil phase is 2%, the aluminum ion concentration in the primary wastewater is 14%, and the pH of the oil phase is 5-6.

[0071] Comparative Example 2

[0072] The difference from Example 1 is that only one hydrolysis is used, the flow rates of the water phase and the oil phase are matched according to a ratio of 3:1, and after the oil phase is treated by the liquid-liquid separator, it is not further separated by the coalescing separator 14, so that the water content in the final oil phase is 4%, the aluminum ion concentration in the wastewater is 5%, and the pH of the oil phase is 4-5.

[0073] Conclusion analysis: The difference between Comparative Example 1 and Example 1 is that the oil phase is not further separated by the rear-end coalescing separator 14, resulting in an increase in the water content in the final oil phase. The increase in the water content in the oil phase will, on the one hand, lead to an increase in the subsequent distillation load. On the other hand, the water in the oil phase may carry aluminum ions, and the acidic substances in the water will corrode the rear-end equipment.

[0074] Comparative Example 2 differs from Example 1 in that only a single hydrolysis step is used, and no further oil phase separation is performed in the subsequent coalescing separator 14. This results in an increased water content in the final oil phase. This increased water content in the oil phase not only increases the subsequent distillation load, but also potentially carries aluminum ions with it. Furthermore, the acidic substances in the water can corrode downstream equipment. Furthermore, the aluminum ion concentration in the separated aqueous phase is relatively low, making it difficult to recover the subsequent aluminum resource.

[0075] It should be noted that although the final oil phase of Example 1 contains a trace amount of water, it is within the normal range and will not increase the subsequent distillation load. The acidic substances in the water will not corrode the back-end equipment.

[0076] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0077] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0078] In the present invention, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection, or communication; direct connection or indirect connection through an intermediate medium; internal communication between two elements or interaction between two elements, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0079] In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediary. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0080] In the present invention, the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and the features of different embodiments or examples without contradiction.

[0081] Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A device for continuous and synchronous graded hydrolysis of acylation reaction liquid, characterized in that: The invention comprises a raw oil tank, a first water storage tank, a second water storage tank, a low-temperature cooling bath, a primary microchannel reactor, a secondary microchannel reactor, a primary liquid separating tank, a secondary liquid separating tank, a primary water tank, a primary oil tank, a secondary water tank, a secondary oil tank and a coalescing separator, wherein the outlet of the raw oil tank and the outlet of the first water storage tank are connected to the inlet of the low-temperature cooling bath via a pipeline, the outlet of the low-temperature cooling bath is connected to the inlet of the primary microchannel reactor, the hydrolysis outlet of the primary microchannel reactor is connected in parallel to the inlets of several primary liquid separating tanks, the primary liquid separating tank is provided with a water outlet and an oil outlet, the water outlet of the primary liquid separating tank is connected to the inlet of the primary water tank, and the oil outlet of the primary liquid separating tank is connected to the inlet of the primary oil tank; The outlet of the first oil tank and the outlet of the second water storage tank are connected to the inlet of the secondary microchannel reactor through a pipeline. The hydrolysis outlet of the secondary microchannel reactor is connected in parallel to the inlets of several secondary liquid separation tanks. The secondary liquid separation tank is provided with a water outlet and an oil outlet. The water outlet of the secondary liquid separation tank is connected to the inlet of the secondary water tank, the oil outlet of the secondary liquid separation tank is connected to the inlet of the secondary oil tank, and the outlet of the secondary oil tank is connected to the inlet of the coalescing separator. The coalescing separator is provided with a water phase outlet and an oil phase outlet.

2. The device for continuous synchronous graded hydrolysis of acylation reaction liquid according to claim 1, characterized in that: There are two first-level liquid separating tanks, namely liquid separating tank No. 1 and liquid separating tank No.

2. The pipeline of the hydrolysis outlet of the first-level microchannel reactor is connected to the inlet of liquid separating tank No. 1 and the inlet of liquid separating tank No. 2 through a three-way valve. The bottom end of liquid separating tank No. 1 and the bottom end of liquid separating tank No. 2 are both connected to three-way valves. One branch of the three-way valve of liquid separating tank No. 1 is connected to the inlet of the first-level water tank, and the other branch of the three-way valve of liquid separating tank No. 1 is connected to the inlet of the first-level oil tank. One branch of the three-way valve of liquid separating tank No. 2 is connected to the inlet of the first-level water tank, and the other branch of the three-way valve of liquid separating tank No. 2 is connected to the inlet of the first-level oil tank.

3. The device for continuous synchronous graded hydrolysis of acylation reaction liquid according to claim 2, characterized in that: There are two secondary liquid separating tanks, namely liquid separating tank No. 3 and liquid separating tank No.

4. The pipeline of the hydrolysis outlet of the secondary microchannel reactor is connected to the inlet of liquid separating tank No. 3 and the inlet of liquid separating tank No. 4 through a three-way valve. The bottom end of liquid separating tank No. 3 and the bottom end of liquid separating tank No. 4 are both connected to three-way valves. One branch of the three-way valve of liquid separating tank No. 3 is connected to the inlet of the secondary water tank, and the other branch of the three-way valve of liquid separating tank No. 3 is connected to the inlet of the secondary oil tank. One branch of the three-way valve of liquid separating tank No. 4 is connected to the inlet of the secondary water tank, and the other branch of the three-way valve of liquid separating tank No. 4 is connected to the inlet of the secondary oil tank.

4. The device for continuous synchronous graded hydrolysis of acylation reaction liquid according to claim 3, characterized in that: The No. 1 liquid separation tank, the No. 2 liquid separation tank, the No. 3 liquid separation tank and the No. 4 liquid separation tank are all connected with an air pump for extracting waste gas, and the outlet of the air pump is connected to the alkali liquid tank.

5. A method for continuous synchronous graded hydrolysis of an acylation reaction solution, characterized in that: The device for continuous synchronous graded hydrolysis of the acylation reaction solution according to any one of claims 1 to 4 comprises the following steps: S1, open the first water storage tank and the raw oil tank storing the acylation reaction liquid, match the flow rate of the water phase and the oil phase in a 1:1 ratio, mix them in a low-temperature cooling bath, and then enter the first microchannel reactor. After ultrasonic vibration for a period of time, the mixed liquid flows out of the hydrolysis outlet of the first microchannel reactor and enters the first separator tank; S2, when the No. 1 separatory tank reaches the set liquid level, the hydrolysis outlet is switched to the No. 2 separatory tank by using the three-way valve, and the mixed liquid in the No. 1 separatory tank is heated and stirred at the same time. After the oil and water in the No. 1 separatory tank are allowed to stand and separate, the three-way valve at the bottom of the No. 1 separatory tank is opened, and the oil phase at the lower layer in the No. 1 separatory tank is first collected into the first-level oil tank. After the oil phase is collected, the pipeline of the three-way valve at the bottom of the No. 1 separatory tank is switched, and the remaining water phase in the No. 1 separatory tank is collected into the first-level water tank. After the water phase is collected, the three-way valve of the No. 1 separatory tank is closed, and the No. 1 separatory tank is ready for use; S3, when the No. 2 separatory tank reaches the set liquid level, the hydrolysis outlet is switched to the No. 1 separatory tank by using the three-way valve, and the mixed liquid in the No. 2 separatory tank is heated and stirred at the same time. After the oil and water in the No. 2 separatory tank are allowed to stand and stratify, the three-way valve at the bottom of the No. 2 separatory tank is opened, and the oil phase located at the lower layer in the No. 2 separatory tank is first collected into the primary oil tank. After the oil phase is collected, the pipeline of the three-way valve at the bottom of the No. 2 separatory tank is switched, and the remaining water phase in the No. 2 separatory tank is collected into the primary water tank. After the water phase is collected, the three-way valve of the No. 2 separatory tank is closed, and the No. 2 separatory tank is ready for use. Steps S2 and S3 are repeated several times until the raw material oil tank is completely emptied; S4, when the first-level oil tank reaches the set liquid level, the first-level oil tank and the second water storage tank are opened, the flow rate of the water phase and the oil phase is matched in a ratio of 2:1, and the mixed liquid enters the second-level microchannel reactor and is ultrasonically vibrated for a period of time. The mixed liquid flows out of the hydrolysis outlet of the second-level microchannel reactor and enters the third separation tank; S5, when the No. 3 separator tank reaches the set liquid level, the hydrolysis outlet is switched to the No. 4 separator tank by using the three-way valve, and the mixed liquid in the No. 3 separator tank is heated and stirred at the same time. After the oil and water in the No. 3 separator tank are allowed to stand and separate, the three-way valve at the bottom of the No. 3 separator tank is opened, and the oil phase at the lower layer in the No. 3 separator tank is first collected into the secondary oil tank. After the oil phase is collected, the pipeline of the three-way valve at the bottom of the No. 3 separator tank is switched, and the remaining water phase in the No. 3 separator tank is collected into the secondary water tank. After the water phase is collected, the three-way valve of the No. 3 separator tank is closed, and the No. 3 separator tank is ready for use; S6, when the No. 4 separatory tank reaches the set liquid level, the hydrolysis outlet is switched to the No. 3 separatory tank by using the three-way valve, and the mixed liquid in the No. 4 separatory tank is heated and stirred at the same time. After the oil and water in the No. 4 separatory tank are allowed to stand and separate, the three-way valve at the bottom of the No. 4 separatory tank is opened, and the oil phase in the lower layer of the No. 4 separatory tank is first collected into the secondary oil tank. After the oil phase is collected, the pipeline of the three-way valve at the bottom of the No. 4 separatory tank is switched to collect the remaining water phase in the No. 4 separatory tank into the secondary water tank. After the water phase is collected, the three-way valve of the No. 4 separatory tank is closed, and the No. 4 separatory tank is ready for use. Steps S5 and S6 are repeated several times until the primary oil tank is completely emptied; S7, the secondary oil tank passes the oil phase into the coalescing separator to further remove the emulsified water.

6. The method for continuous synchronous graded hydrolysis of acylation reaction solution according to claim 5, characterized in that: The water in the primary water tank is stripped of organic matter by steam, decolorized by activated carbon, and then polymerized by an alkalizing agent to obtain liquid PAC.

7. The method for continuous synchronous graded hydrolysis of acylation reaction solution according to claim 5, characterized in that: The water in the secondary water tank, the stripped water in the primary water tank, and the water separated by the coalescing separator are mixed and filtered first, and then subjected to Fenton oxidation and electrocatalytic oxidation to treat organic matter, thereby reducing COD to below 500.

8. The method for continuous synchronous graded hydrolysis of acylation reaction solution according to claim 5, characterized in that: The temperature inside the primary microchannel reactor and the secondary microchannel reactor is 30-35°C.

9. The method for continuous synchronous graded hydrolysis of acylation reaction solution according to claim 5, characterized in that: The heating temperature in the No. 1 separating tank, the No. 2 separating tank, the No. 3 separating tank and the No. 4 separating tank is 60° C., the stirring speed is 200 r / min, and the stirring time is 30 min.

10. The method for continuous synchronous graded hydrolysis of acylation reaction solution according to claim 5, characterized in that: The temperature of the low-temperature cooling bath is 0°C.

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