DCS (Distributed Control System) sequential control production system and production method of 2, 5-dimethyl-2, 5-dihydroperoxide hexane

Abstract

The invention belongs to the technical field of chemical production, and particularly relates to a DCS (Distributed Control System) sequential control production system and a production method of 2, 5-dimethyl-2, 5-dihydroperoxide hexane. The invention provides a DCS sequential control production system. The DCS sequential control production system comprises a reaction kettle, a plurality of centrifuges, a synthetic mother liquor collecting tank, a washing mother liquor collecting tank and a DCS controller, the DCS controller is electrically connected with the stirrer, the on-line thermometer, the cooling water inlet valve, the reaction kettle weighing module, the centrifugal machine, the reaction kettle discharging valve, the centrifugal machine feeding valve, the spraying water valve, the synthetic mother liquor feeding valve, the washing mother liquor feeding valve and the on-line pH meter. According to the present invention, the DCS sequential control production system is adopted to achieve the automatic production of the 2, 5-dimethyl-2, 5-dihydroperoxide hexane, the production process flow is simple, only the feeding preparation is needed, the reaction and the post-treatment process after the feeding is completed are completed through the sequential control of the DCS, and the method is suitable for the industrial application.

Description

Technical Field

[0001] The invention belongs to the technical field of chemical production, and particularly relates to a DCS sequential control production system and a production method for 2,5-dimethyl-2,5-dihydroperoxide hexane. Background Art

[0002] 2,5-Dimethyl-2,5-di(tert-butylperoxy)hexane (abbreviated as 101) is an important organic peroxide, commonly used as a free radical initiator in polymerization processes and to improve the viscosity of polyolefins. It is also used in silicone rubber vulcanization products. Due to its high tensile strength and hardness, and low elongation and compression set, it is used as an effective high-temperature vulcanizer for vinyl rubber, a hardener for unsaturated polyesters, and a vulcanizer for products such as fluororubber, polyurethane rubber, and EPDM. The preparation of "101" mainly involves two stages: peroxidation and tert-butylation.

[0003] The first peroxidation stage uses 2,5-dimethyl-2,5-hexanediol and hydrogen peroxide as raw materials, and undergoes an oxidation reaction under sulfuric acid catalysis to synthesize 2,5-dimethyl-2,5-dihydroperoxyhexane. This production process is currently performed industrially using a batch process. Post-processing requires centrifugal washing and other operations, which requires long-term operation and high labor costs. Furthermore, the pH value of the material must be controlled to prevent decomposition of 2,5-dimethyl-2,5-dihydroperoxyhexane under acidic conditions, posing a safety hazard. Excessive washing can lead to product loss due to dissolution.

[0004] In summary, the current production process of 2,5-dimethyl-2,5-dihydroperoxyhexane is complicated to operate, has high labor costs and low production efficiency. Summary of the Invention

[0005] The present invention aims to provide a DCS sequential control production system and a production method for 2,5-dimethyl-2,5-dihydroperoxyhexane. The production method provided by the present invention has a simple production process, effectively reduces labor input, has high production efficiency and high safety, and is suitable for industrial application.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] The present invention provides a DCS sequential control production system for 2,5-dimethyl-2,5-dihydroperoxyhexane, comprising a reactor, wherein the reactor is provided with an agitator, an online thermometer and a cooling unit, wherein a cooling water inlet valve is provided on a water inlet pipe of the cooling unit; and the reactor is provided with a reactor weighing module;

[0008] Several centrifuges, each comprising a centrifugal unit and a bottom silo, the bottom silo being provided with a bottom silo feed port, the reactor and the centrifuge being connected by a first mother liquor receiving pipeline, the first mother liquor receiving pipeline being provided with a reactor discharge valve and a centrifuge feed valve in sequence from the reactor to the centrifuge, the centrifuge being provided with a process water delivery pipeline, and the process water delivery pipeline being provided with a spray water valve;

[0009] A synthetic mother liquor collecting tank, wherein the centrifuge and the synthetic mother liquor collecting tank are connected by a second mother liquor receiving pipeline, and a synthetic mother liquor feeding valve is provided on the second mother liquor receiving pipeline;

[0010] A mother wash liquor collecting tank, wherein the centrifuge and the mother wash liquor collecting tank are connected by a washing water receiving pipeline, and the washing water receiving pipeline is provided with a mother wash liquor feed valve and an online pH meter;

[0011] A DCS controller is electrically connected to the agitator, an online thermometer, a cooling water inlet valve, a reactor weighing module, a centrifuge, a reactor discharge valve, a centrifuge feed valve, a spray water valve, a synthesis mother liquor feed valve, a water washing mother liquor feed valve and an online pH meter.

[0012] Preferably, the number of the centrifuges is 2, and the two centrifuges are connected in parallel.

[0013] Preferably, the centrifuge is a bag centrifuge; the synthetic mother liquor feed valve and the water washing mother liquor feed valve are pneumatic valves, and the washing water receiving pipeline is sequentially provided with a water washing mother liquor feed valve and an online pH meter in the direction from the centrifuge to the water washing mother liquor collecting tank.

[0014] The present invention provides a production method of 2,5-dimethyl-2,5-dihydroperoxide hexane based on DCS sequential control, which is produced by using the DCS sequential control production system described in the above technical solution;

[0015] The following steps are involved:

[0016] (1) adding a reaction solution comprising H2O2, H2SO4 and water into a reactor, turning on a stirrer, adding 2,5-dimethyl-2,5-hexanediol into the reactor, and performing a heat preservation reaction. During the reaction process, a DCS controller is used to control a cooling water inlet valve. When the temperature of the reactor is greater than a first set temperature, the cooling water inlet valve is opened. When the temperature of the reactor is less than a second set temperature, the cooling water inlet valve is closed.

[0017] (2) After the heat preservation reaction reaches the set time, a reaction slurry is obtained, the centrifuge is started, the synthetic mother liquor feed valve is opened, and when the speed of the centrifuge reaches the set value, the centrifuge feed valve and the reactor discharge valve are opened with a delay to discharge the reaction slurry into the centrifuge;

[0018] (3) When the reactor weighing module is less than or equal to the set value, close the agitator, reactor discharge valve, and centrifuge feed valve, and continue centrifugation;

[0019] (4) Close the synthetic mother liquor feed valve, open the water washing mother liquor feed valve, delay opening the spray water valve, close the spray water valve after the spraying is completed, and continue centrifugation;

[0020] (5) Open the spray water valve, close the spray water valve after the spraying is completed, and continue centrifugation;

[0021] (6) Circulate step (5) until the online pH meter reaches the qualified index;

[0022] (7) Open the feed port of the bottom silo, close the centrifuge, discharge the product obtained from the centrifugal unit into the bottom silo, and close the water washing mother liquor feed valve.

[0023] Preferably, in step (7), after the centrifuge is turned off, when the centrifuge speed drops to 0, the process also includes delaying 10 to 15 seconds to open the centrifuge bag puller to discharge the product into the bottom silo.

[0024] Preferably, in step (1), the content of H2O2 in the reaction solution is 25-40 wt%, and the content of H2SO4 is 30-50 wt%; the stirring speed is 500-1000 rpm;

[0025] The molar ratio of 2,5-dimethyl-2,5-hexanediol, H2O2 and H2SO4 is 1:4-8:2-3;

[0026] The temperature of the heat preservation reaction is 20-35°C, the first setting temperature is 35°C, and the second setting temperature is 20°C.

[0027] Preferably, in step (2), the set time of the insulation reaction is 20 to 40 minutes; the rotation speed of the centrifuge is 1000 to 1200 rpm, and the delay time for opening the centrifuge feed valve or the reactor discharge valve is 20 to 30 seconds.

[0028] Preferably, in step (3), the setting value of the reactor weighing module is 3 kg, and the time of continuing centrifugation is 20 to 25 minutes;

[0029] In step (4), the delay time for opening the spray water valve is 10 to 15 seconds, the spraying time is 2 to 3 minutes, and the centrifugation time is 10 to 15 minutes;

[0030] In step (5), the spraying time is 2 to 3 minutes, and the centrifugation time is 10 to 15 minutes.

[0031] Preferably, in step (6), the qualified index of the online pH meter is ≥3.

[0032] Preferably, the content of 2,5-dimethyl-2,5-dihydroperoxyhexane in the product is 75-85 wt%;

[0033] The acidity of the product is ≤0.1%.

[0034] The present invention provides a DCS sequential control production system for 2,5-dimethyl-2,5-dihydroperoxyhexane, comprising a reactor, wherein the reactor is provided with an agitator, an online thermometer and a cooling unit, wherein a cooling water inlet valve is provided on a water inlet pipe of the cooling unit; the reactor is provided with a reactor weighing module; and a plurality of centrifuges, wherein the centrifuges comprise a centrifugal unit and a bottom silo, wherein the bottom silo is provided with a bottom silo feed port, wherein the reactor and the centrifuges are connected by a first mother liquor receiving pipeline, wherein a reactor discharge valve and a centrifuge feed valve are sequentially provided on the first mother liquor receiving pipeline in a direction from the reactor to the centrifuge, and wherein the centrifuges are provided with a process water delivery pipeline. , a spray water valve is provided on the process water delivery pipeline; a synthetic mother liquor collecting tank, the centrifuge and the synthetic mother liquor collecting tank are connected by a second mother liquor receiving pipeline, and a synthetic mother liquor feed valve is provided on the second mother liquor receiving pipeline; a water washing mother liquor collecting tank, the centrifuge and the water washing mother liquor collecting tank are connected by a washing water receiving pipeline, and a water washing mother liquor feed valve and an online pH meter are provided on the washing water receiving pipeline; a DCS controller, the DCS controller is electrically connected to the agitator, the online thermometer, the cooling water inlet valve, the reactor weighing module, the centrifuge, the reactor discharge valve, the centrifuge feed valve, the spray water valve, the synthetic mother liquor feed valve, the water washing mother liquor feed valve and the online pH meter. The present invention uses a DCS sequential control production system to achieve automated production of 2,5-dimethyl-2,5-dihydroperoxide hexane. The production process is simple and only requires feeding preparation. The reaction and post-processing steps after feeding are completed by the DCS sequential control to obtain a washed product (i.e., crude 2,5-dimethyl-2,5-dihydroperoxide hexane). The synthesis mother liquor and the water-washing mother liquor are discharged into corresponding receiving tanks for collection without the need for human control intervention. Therefore, the present invention uses a DCS sequential control production system to achieve the production and water-washing post-processing of 2,5-dimethyl-2,5-dihydroperoxide hexane. The production process is simple, labor input is effectively reduced, production efficiency is high, safety is high, and the product is suitable for industrial application.

[0035] Furthermore, the product has a 2,5-dimethyl-2,5-dihydroperoxyhexane content of 75-85 wt % and an acidity of ≤0.1%. The production method provided by the present invention produces a qualified crude 2,5-dimethyl-2,5-dihydroperoxyhexane product with qualified acidity, a safe intermediate product, and a qualified content, suitable for the next step of feeding. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 This is a schematic structural diagram of the DCS sequential control production system for 2,5-dimethyl-2,5-dihydroperoxide hexane provided by the present invention;

[0037] Figure 2 A flow chart of the production method of 2,5-dimethyl-2,5-dihydroperoxide hexane based on DCS sequential control provided by the present invention;

[0038] Figure 3 This is the control timing diagram of DCS sequential control in the production process of 2,5-dimethyl-2,5-dihydroperoxyhexane;

[0039] In the figure: 1 is a reactor; 2 is a reactor discharge valve; 3 is a first spray water valve; 4 is a second spray water valve; 5 is a first centrifuge feed valve; 6 is a second centrifuge feed valve; 7 is a first centrifuge; 8 is a second centrifuge; 9 is a bottom silo; 10 is a first synthesis mother liquor feed valve; 11 is a first water-wash mother liquor feed valve; 12 is a synthesis mother liquor collecting tank; 13 is a water-wash mother liquor collecting tank; 14 is a first online pH meter; 15 is a second synthesis mother liquor feed valve; 16 is a second water-wash mother liquor feed valve; 17 is a second online pH meter; 18 is a DCS controller. DETAILED DESCRIPTION

[0040] The present invention provides a DCS sequential control production system for 2,5-dimethyl-2,5-dihydroperoxyhexane, comprising a reactor, wherein the reactor is provided with an agitator, an online thermometer and a cooling unit, wherein a cooling water inlet valve is provided on a water inlet pipe of the cooling unit; and the reactor is provided with a reactor weighing module;

[0041] Several centrifuges, each comprising a centrifugal unit and a bottom silo, the bottom silo being provided with a bottom silo feed port, the reactor and the centrifuge being connected by a first mother liquor receiving pipeline, the first mother liquor receiving pipeline being provided with a reactor discharge valve and a centrifuge feed valve in sequence from the reactor to the centrifuge, the centrifuge being provided with a process water delivery pipeline, and the process water delivery pipeline being provided with a spray water valve;

[0042] A synthetic mother liquor collecting tank, wherein the centrifuge and the synthetic mother liquor collecting tank are connected by a second mother liquor receiving pipeline, and a synthetic mother liquor feeding valve is provided on the second mother liquor receiving pipeline;

[0043] A mother wash liquor collecting tank, wherein the centrifuge and the mother wash liquor collecting tank are connected by a washing water receiving pipeline, and the washing water receiving pipeline is provided with a mother wash liquor feed valve and an online pH meter;

[0044] A DCS controller is electrically connected to the agitator, an online thermometer, a cooling water inlet valve, a reactor weighing module, a centrifuge, a reactor discharge valve, a centrifuge feed valve, a spray water valve, a synthesis mother liquor feed valve, a water washing mother liquor feed valve and an online pH meter.

[0045] In the present invention, unless otherwise specified, all preparation raw materials / components are commercially available products well known to those skilled in the art.

[0046] Figure 1 The present invention provides a schematic structural diagram of a DCS sequential control production system for 2,5-dimethyl-2,5-dihydroperoxyhexane. Figure 1 The DCS sequential control production system provided by the present invention is described in detail.

[0047] The DCS sequentially controlled production system for 2,5-dimethyl-2,5-dihydroperoxyhexane provided herein includes a reactor. In the reactor, raw materials (H2O2 and 2,5-dimethyl-2,5-hexanediol) react under H2SO4 catalysis to produce the 2,5-dimethyl-2,5-dihydroperoxyhexane product. The reactor is equipped with an agitator, an online thermometer, and a cooling unit. The cooling unit's water inlet pipe is equipped with a cooling water inlet valve. The reactor is also equipped with a reactor weighing module.

[0048] In the present invention, the temperature of the reactor is linked to the reactor cooling water inlet valve.

[0049] The DCS sequential control production system for 2,5-dimethyl-2,5-dihydroperoxyhexane provided by the present invention includes several centrifuges. In the present invention, the centrifuge is used to separate and wash the target product (2,5-dimethyl-2,5-dihydroperoxyhexane). The centrifuge includes a centrifugal unit and a bottom silo. The bottom silo is provided with a bottom silo feed port. The reactor and the centrifuge are connected by a first mother liquor receiving pipeline. The first mother liquor receiving pipeline is provided with a reactor discharge valve and a centrifuge feed valve in sequence from the reactor to the centrifuge. The centrifuge is provided with a process water delivery pipeline, and the process water delivery pipeline is provided with a spray water valve. The process water delivery pipeline is used to deliver process water to the centrifuge for washing the target product 2,5-dimethyl-2,5-dihydroperoxyhexane.

[0050] As one or more embodiments of the present invention, the number of the centrifuges is two, and the two centrifuges are connected in parallel.

[0051] As one or more embodiments of the present invention, the centrifuge is a bag centrifuge.

[0052] As one or more embodiments of the present invention, the number of the reactor discharge valve is one.

[0053] As one or more embodiments of the present invention, the number of the centrifuge feed valves is 2, namely a first centrifuge feed valve 5 and a second centrifuge feed valve 6 .

[0054] As one or more embodiments of the present invention, the number of the spray water valves is 2, namely a first spray water valve 3 and a second spray water valve 4.

[0055] The DCS sequentially controlled production system for 2,5-dimethyl-2,5-dihydroperoxyhexane provided herein includes a synthesis mother liquor collection tank. In the present invention, the synthesis mother liquor collection tank is used to collect the synthesis mother liquor separated by the centrifuge. The centrifuge and the synthesis mother liquor collection tank are connected by a second mother liquor receiving pipeline, which is equipped with a synthesis mother liquor feed valve.

[0056] As one or more embodiments of the present invention, the synthetic mother liquor feed valve is a pneumatic valve.

[0057] As one or more embodiments of the present invention, the number of the synthetic mother liquor feed valves is 2, namely a first synthetic mother liquor feed valve 10 and a second synthetic mother liquor feed valve 15 .

[0058] The DCS sequentially controlled production system for 2,5-dimethyl-2,5-dihydroperoxyhexane provided herein includes a mother wash liquor collection tank. The mother wash liquor collection tank is used to collect mother wash liquor obtained by washing in the centrifuge. A wash water receiving pipeline connects the centrifuge and the mother wash liquor collection tank. The mother wash liquor feed valve and an online pH meter are provided on the wash water receiving pipeline.

[0059] As one or more embodiments of the present invention, the water wash mother liquor feed valve is a pneumatic valve.

[0060] As one or more embodiments of the present invention, a washing water receiving pipeline is provided with a washing mother liquor feed valve and an online pH meter in sequence in the direction from the centrifuge to the washing mother liquor collecting tank.

[0061] As one or more embodiments of the present invention, the number of the water-washing mother liquor feed valves is 2, namely a first water-washing mother liquor feed valve 11 and a second water-washing mother liquor feed valve 16 .

[0062] As one or more embodiments of the present invention, the number of the online pH meters is two, namely a first online pH meter 14 and a second online pH meter 17 .

[0063] The present invention provides a DCS sequential control production system for 2,5-dimethyl-2,5-dihydroperoxyhexane, including a DCS controller. In the present invention, the DCS controller is used to implement DCS sequential control. The DCS controller is electrically connected to an agitator, an online thermometer, a cooling water inlet valve, a reactor weighing module, a centrifuge, a reactor discharge valve, a centrifuge feed valve, a spray water valve, a synthesis mother liquor feed valve, a water wash mother liquor feed valve, and an online pH meter.

[0064] In the present invention, the DCS controller controls the opening and closing of the agitator. The DCS controller receives the temperature signal from the online thermometer. The DCS controller controls the opening and closing of the cooling water inlet valve. The DCS controller controls the weight signal received from the reactor weighing module. The DCS controller controls the opening and closing of the centrifuge. The DCS controller controls the opening and closing of the bottom hopper feed port of the centrifuge. The DCS controller controls the opening and closing of the reactor discharge valve. The DCS controller controls the opening and closing of the centrifuge feed valve. The DCS controller controls the opening and closing of the spray water valve. The DCS controller controls the opening and closing of the synthesis mother liquor feed valve. The DCS controller controls the opening and closing of the water wash mother liquor feed valve. The DCS controller receives the pH value signal from the online pH meter.

[0065] In one or more embodiments of the present invention, the DCS controller is Hollysys's K-CU11, and the sequential control program written in the DCS controller is SFC.

[0066] The present invention provides a production method of 2,5-dimethyl-2,5-dihydroperoxide hexane based on DCS sequential control, which is produced by using the DCS sequential control production system described in the above technical solution;

[0067] The following steps are involved:

[0068] (1) adding a reaction solution comprising H2O2, H2SO4 and water into a reactor, turning on a stirrer, adding 2,5-dimethyl-2,5-hexanediol into the reactor, and performing a heat preservation reaction. During the reaction process, a DCS controller is used to control a cooling water inlet valve. When the temperature of the reactor is greater than a first set temperature, the cooling water inlet valve is opened. When the temperature of the reactor is less than a second set temperature, the cooling water inlet valve is closed.

[0069] (2) After the heat preservation reaction reaches the set time, a reaction slurry is obtained, the centrifuge is started, the synthetic mother liquor feed valve is opened, and when the speed of the centrifuge reaches the set value, the centrifuge feed valve and the reactor discharge valve are opened with a delay to discharge the reaction slurry into the centrifuge;

[0070] (3) When the reactor weighing module is less than or equal to the set value, close the agitator, reactor discharge valve, and centrifuge feed valve, and continue centrifugation;

[0071] (4) Close the synthetic mother liquor feed valve, open the water washing mother liquor feed valve, delay opening the spray water valve, close the spray water valve after the spraying is completed, and continue centrifugation;

[0072] (5) Open the spray water valve, close the spray water valve after the spraying is completed, and continue centrifugation;

[0073] (6) Circulate step (5) until the online pH meter reaches the qualified index;

[0074] (7) Open the feed port of the bottom silo, close the centrifuge, discharge the product obtained from the centrifugal unit into the bottom silo, and close the water washing mother liquor feed valve.

[0075] In the present invention, a reaction solution comprising H2O2, H2SO4, and water is added to a reactor. An agitator is then activated. 2,5-dimethyl-2,5-hexanediol is then added to the reactor. A heat-insulating reaction is then carried out. During the reaction, a DCS controller is used to control a cooling water inlet valve. When the reactor temperature exceeds a first set temperature, the cooling water inlet valve is opened; when the reactor temperature falls below a second set temperature, the cooling water inlet valve is closed. In the present invention, 2,5-dimethyl-2,5-hexanediol is preferably added continuously to the reactor. The H2O2 content in the reaction solution is preferably 25-40 wt%, and in embodiments, may be 29.87 wt%, 38.98 wt%, or 48.48 wt%. The H2SO4 content is preferably 30-50 wt%, and in embodiments, may be 36.18 wt%, 32.6 wt%, or 25.12 wt%. In the present invention, the stirring speed is preferably 500-1000 rpm, and in embodiments, it can be 500 rpm, 1000 rpm, or 750 rpm. The molar ratio of 2,5-dimethyl-2,5-hexanediol, H2O2, and H2SO4 is preferably 1:4-8:2-3, and in embodiments, it can be 1:7:2, 1:6:2.5, or 1:4:2.7. The temperature of the insulation reaction is preferably 20-35°C, more preferably 25-33°C. The first set temperature is preferably 35°C or 33°C, and the second set temperature is preferably 20°C or 25°C.

[0076] In the present invention, after the insulation reaction reaches a set time, a reaction slurry is obtained, and then the centrifuge is started. The synthetic mother liquor feed valve is then opened. After the centrifuge speed reaches a set value, the centrifuge feed valve and the reactor discharge valve are opened with a delayed opening to discharge the reaction slurry into the centrifuge. In the present invention, the order of starting the centrifuge and the synthetic mother liquor feed valve can be interchanged. The set time for the insulation reaction is preferably 20 to 40 minutes, and in embodiments, it can be 30 minutes. The centrifuge speed is preferably 1000 to 1200 rpm. In embodiments of the present invention, the time from centrifuge startup to centrifuge speed reaching the set value (1000 rpm) is preferably 2 minutes. The centrifuge feed valve and reactor discharge valve are opened simultaneously or sequentially. The order of opening is not limited, and the time interval between the openings is negligible. The delay time for opening the centrifuge feed valve or reactor discharge valve is preferably 10 to 30 seconds, and in embodiments, it can be 10 seconds.

[0077] In the present invention, when the reactor weighing module is less than or equal to the set value, the agitator, reactor discharge valve, and centrifuge feed valve are closed, and centrifugation is continued. In the present invention, the reactor weighing module is preferably set to 3 kg, and the centrifugation is continued for 20 to 25 minutes, and in the embodiment, it can be 20 minutes. The centrifuge feed valve and reactor discharge valve are closed simultaneously or sequentially. The order of closing is not limited, and the time interval between the two closings is negligible.

[0078] In the present invention, the synthesis mother liquor feed valve is closed, the wash mother liquor feed valve is opened, and then the spray water valve is opened with a delay. After spraying is completed, the spray water valve is closed; and then centrifugation is continued. In the present invention, the delay time for opening the spray water valve is preferably 10 to 15 seconds. The spraying time is preferably 2 to 3 minutes, and in the embodiment, it can be 2 minutes. The spraying is performed under centrifugation conditions. The centrifugation time is preferably 10 to 15 minutes, and in the embodiment, it can be 10 minutes.

[0079] The present invention opens the spray valve, closes it after spraying, and then continues centrifugation. In the present invention, the spraying time is preferably 2 to 3 minutes, and in the embodiment, it can be 2 minutes. The spraying is performed under centrifugal conditions. The continued centrifugation time is preferably 10 to 15 minutes, and in the embodiment, it can be 10 minutes.

[0080] The present invention repeats the steps of "opening the spray valve, closing the spray valve after spraying, and then continuing centrifugation," wherein the spraying is performed under centrifugation until the online pH meter reaches a qualified index. In the present invention, the qualified index of the online pH meter is preferably ≥3, and more preferably 3.

[0081] The present invention opens the bottom silo feed port, then closes the centrifuge, and then discharges the product obtained from the centrifugal unit into the bottom silo, and then closes the water wash mother liquor feed valve. In the present invention, after closing the centrifuge, when the centrifuge speed drops to 0, the time for the centrifuge speed to drop from 1000 rpm to 0 in the embodiment is preferably 2 minutes. The present invention preferably also includes a delay of 10 to 15 seconds to open the centrifuge bag and discharge the product into the bottom silo. The discharge time in the embodiment is preferably 1 minute. In the present invention, the product is a wet product of 2,5-dimethyl-2,5-bis(hydroperoxide)hexane. The content of 2,5-dimethyl-2,5-dihydroperoxide hexane in the product is preferably 75 to 85% by weight. The acidity of the product is preferably ≤0.1%. The yield of 2,5-dimethyl-2,5-dihydroperoxide hexane in the product is preferably 75 to 80%.

[0082] In summary, the production method process provided by the present invention is simple, only needs to carry out feeding preparation, the production and washing steps after the feeding is completed, and the washed 2,5-dimethyl-2,5-dihydroperoxyhexane crude product (i.e., 2,5-dimethyl-2,5-bis(hydroperoxide)hexane wet product) is obtained, and the synthetic mother liquor and the water-washed mother liquor are discharged into the corresponding receiving tank for collection, without the need for personnel control intervention, to obtain qualified 2,5-dimethyl-2,5-dihydroperoxyhexane crude product, wherein the acidity is qualified, the intermediate product is safe, the content is qualified, and it is suitable for the next step of feeding. The processing steps are simplified, the manual input is reduced, and the safety is increased.

[0083] At the same time, the total time required for DCS sequential control after synthesis in the embodiment of the present invention is 89 minutes, and one reactor can correspond to two centrifuges for sequential control, thereby achieving efficient synthesis processing.

[0084] In order to further illustrate the present invention, the technical solutions provided by the present invention are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0085] In the following examples, Figure 1 A DCS sequential control production system of 2,5-dimethyl-2,5-dihydroperoxyhexane is shown for producing 2,5-dimethyl-2,5-dihydroperoxyhexane. Figure 2 A flow chart of a method for producing 2,5-dimethyl-2,5-dihydroperoxyhexane based on DCS sequential control is provided for the following examples. Figure 3 This is the control timing diagram of DCS sequential control in the production process of 2,5-dimethyl-2,5-dihydroperoxyhexane. Figure 3In the figure, the solid black line represents the time required for the sequence, the dashed blue line represents the waiting time (delay time), and the dashed black line represents the decision to continue washing based on the washing effect. In the following examples, the total time required for DCS sequential control after the reaction is completed is 89 minutes (two "spray-centrifuge" cycles). One reactor can correspond to two centrifuges for sequential control, achieving efficient synthesis processing.

[0086] Specific production methods include:

[0087] The reaction liquid is put into the reactor, and then the DCS controller controls the agitator to start stirring, and then 2,5-dimethyl-2,5-hexanediol is continuously added, and then the DCS controller is turned on to control the temperature in the reactor. The reaction temperature is 20-35°C. When the online thermometer is 35°C, the DCS controller opens the cooling water inlet valve. When the temperature of the online thermometer is 20°C, the DCS controller closes and opens the cooling water inlet valve.

[0088] according to Figure 3 The control timing diagram is shown. Select the first centrifuge or the second centrifuge. Taking the first centrifuge as an example, after the reaction is kept warm for 30 minutes, the DCS controller opens the synthetic mother liquor feed valve and the first centrifuge. The first centrifuge reaches 1000 rpm in 2 minutes. After 10 seconds, the reactor discharge valve and the first centrifuge feed valve are opened. The reactor weighing module that discharges the material into the centrifuge until the reactor is ≤3kg is used. The DCS controller then closes the agitator, the reactor discharge valve, and the centrifuge feed valve. Continue centrifugation for 20 minutes, the DCS controller closes the synthetic mother liquor feed valve, the DCS controller opens the water washing mother liquor feed valve, opens the first spray water valve after 10 seconds, closes the first spray water valve after 2 minutes, continues centrifugation for 10 minutes, opens the first spray water valve, closes it after 2 minutes, continues centrifugation for 10 minutes until the pH value is qualified (the pH value qualification index is ≥3), opens the bottom silo feed port after the pH value is qualified, closes the first centrifuge, and when the speed of the first centrifuge drops to 0 after 2 minutes, opens the first centrifuge bag pulling machine after 10 seconds, puts the material into the bottom silo for 1 minute, closes the water washing mother liquor feed valve, and ends the sequential control production.

[0089] Embodiment 1:

[0090] A reaction liquid (H2SO4 content of 29.87wt%, H2O2 content of 36.18wt%, and the balance water) was pre-prepared, and the molar ratio of 2,5-dimethyl-2,5-hexanediol: H2O2: H2SO4 was controlled to be 1:7:2. The reaction liquid was added to the reactor, and the DCS controller controlled the agitator to start at a stirring speed of 1000rpm. 2,5-dimethyl-2,5-hexanediol was added, and the temperature was controlled at 20-35°C. After the feeding was completed, the DCS sequence control was put into place, and the first centrifuge was selected. After the DCS sequence control was completed, a wet product of 2,5-dimethyl-2,5-bis(hydroperoxide)hexane was obtained, with a 2,5-dimethyl-2,5-bis(hydroperoxide)hexane content of 81.52%, a 2,5-dimethyl-2,5-bis(hydroperoxide)hexane yield of 79.8%, and an acidity of the wet product of 0.05%.

[0091] Example 2:

[0092] The reaction liquid (H2SO4 content 38.98wt%, H2O2 content 32.6wt%, balance water) was pre-prepared, the molar ratio of 2,5-dimethyl-2,5-hexanediol: H2O2: H2SO4 was controlled to be 1:6:2.5, the reaction liquid was added to the reactor 1, the DCS controller controlled the agitator to start, the stirring speed was 750rpm, 2,5-dimethyl-2,5-hexanediol was added, the temperature was controlled at 20-35°C, after the feeding was completed, the DCS sequence control was put into place, centrifuge B was selected, and after the DCS sequence control was completed, a wet product of 2,5-dimethyl-2,5-bis(hydroperoxide)hexane was obtained, the content of 2,5-dimethyl-2,5-bis(hydroperoxide)hexane was 78.56%, the yield of 2,5-dimethyl-2,5-bis(hydroperoxide)hexane was 78.4%, and the acidity of the wet product was 0.07%.

[0093] Example 3:

[0094] The reaction liquid (H2SO4 content 48.48wt%, H2O2 content 25.12wt%, balance water) was pre-prepared, the molar ratio of 2,5-dimethyl-2,5-hexanediol: H2O2: H2SO4 was controlled to be 1:4:2.7, the reaction liquid was added to the reactor 1, the DCS controller controlled the agitator to start, the stirring speed was 500rpm, 2,5-dimethyl-2,5-hexanediol was added, the temperature was controlled at 20-35°C, after the feeding was completed, the DCS sequence control was put into place, centrifuge A was selected, and after the DCS sequence control was completed, a wet product of 2,5-dimethyl-2,5-bis(hydroperoxide)hexane was obtained, the content of 2,5-dimethyl-2,5-bis(hydroperoxide)hexane was 79.12%, the yield of 2,5-dimethyl-2,5-bis(hydroperoxide)hexane was 77.9%, and the acidity of the wet product was 0.09%.

[0095] As can be seen from the above examples, the production method provided by the present invention has a simple process flow. Only feeding preparation is required. After the feeding is completed, the production and washing steps are completed through the sequential control of the DCS to obtain the washed crude 2,5-dimethyl-2,5-dihydroperoxyhexane. The synthesis mother liquor and the water-washed mother liquor are discharged into the corresponding receiving tank for collection. No human control intervention is required, and a qualified crude 2,5-dimethyl-2,5-dihydroperoxyhexane product is obtained, wherein the acidity is qualified, the intermediate product is safe, and the content is qualified, which is suitable for the next feeding step. This simplifies the processing steps, reduces labor input, and increases safety.

[0096] At the same time, the total time required for DCS sequential control after synthesis in the present invention is 89 minutes, and one reactor can correspond to two centrifuges for sequential control, thereby achieving efficient synthesis processing.

[0097] Although the above embodiment provides a detailed description of the present invention, it is only a part of the embodiments of the present invention, not all of the embodiments. Other embodiments can be obtained based on this embodiment without creativity, and these embodiments all fall within the scope of protection of the present invention.

Claims

1. A DCS sequential control production system for 2,5-dimethyl-2,5-dihydroperoxyhexane, characterized in that: The reactor comprises a stirrer, an online thermometer and a cooling unit, a water inlet pipe of the cooling unit is provided with a cooling water inlet valve; the reactor is provided with a reactor weighing module; Several centrifuges, each comprising a centrifugal unit and a bottom silo, the bottom silo being provided with a bottom silo feed port, the reactor and the centrifuge being connected by a first mother liquor receiving pipeline, the first mother liquor receiving pipeline being provided with a reactor discharge valve and a centrifuge feed valve in sequence from the reactor to the centrifuge, the centrifuge being provided with a process water delivery pipeline, and the process water delivery pipeline being provided with a spray water valve; A synthetic mother liquor collecting tank, wherein the centrifuge and the synthetic mother liquor collecting tank are connected by a second mother liquor receiving pipeline, and a synthetic mother liquor feeding valve is provided on the second mother liquor receiving pipeline; A mother wash liquor collecting tank, wherein the centrifuge and the mother wash liquor collecting tank are connected by a washing water receiving pipeline, and the washing water receiving pipeline is provided with a mother wash liquor feed valve and an online pH meter; A DCS controller is electrically connected to the agitator, an online thermometer, a cooling water inlet valve, a reactor weighing module, a centrifuge, a reactor discharge valve, a centrifuge feed valve, a spray water valve, a synthesis mother liquor feed valve, a water washing mother liquor feed valve and an online pH meter.

2. The DCS sequential control production system according to claim 1, characterized in that: There are two centrifuges, which are connected in parallel.

3. The DCS sequential control production system according to claim 1, characterized in that: The centrifuge is a bag centrifuge; the synthetic mother liquor feed valve and the water washing mother liquor feed valve are pneumatic valves; the washing water receiving pipeline is sequentially provided with a water washing mother liquor feed valve and an online pH meter in the direction from the centrifuge to the water washing mother liquor collecting tank.

4. A production method of 2,5-dimethyl-2,5-dihydroperoxide hexane based on DCS sequential control, characterized in that: Production is carried out using the DCS sequential control production system according to any one of claims 1 to 3; The following steps are involved: (1) adding a reaction solution comprising H2O2, H2SO4 and water into a reactor, turning on a stirrer, adding 2,5-dimethyl-2,5-hexanediol into the reactor, and performing a heat preservation reaction. During the reaction process, a DCS controller is used to control a cooling water inlet valve. When the temperature of the reactor is greater than a first set temperature, the cooling water inlet valve is opened. When the temperature of the reactor is less than a second set temperature, the cooling water inlet valve is closed. (2) After the heat preservation reaction reaches the set time, a reaction slurry is obtained, the centrifuge is started, the synthetic mother liquor feed valve is opened, and when the speed of the centrifuge reaches the set value, the centrifuge feed valve and the reactor discharge valve are opened with a delay to discharge the reaction slurry into the centrifuge; (3) When the reactor weighing module is less than or equal to the set value, close the agitator, reactor discharge valve, and centrifuge feed valve, and continue centrifugation; (4) Close the synthetic mother liquor feed valve, open the water washing mother liquor feed valve, delay opening the spray water valve, close the spray water valve after the spraying is completed, and continue centrifugation; (5) Open the spray water valve, close the spray water valve after the spraying is completed, and continue centrifugation; (6) Circulate step (5) until the online pH meter reaches the qualified index; (7) Open the feed port of the bottom silo, close the centrifuge, discharge the product obtained from the centrifugal unit into the bottom silo, and close the water washing mother liquor feed valve.

5. The production method according to claim 4, characterized in that In step (7), after the centrifuge is turned off, when the centrifuge speed drops to 0, the centrifuge bag is opened with a delay of 10 to 15 seconds to discharge the product into the bottom silo.

6. The production method according to claim 4, characterized in that In step (1), the H2O2 content in the reaction solution is 25-40 wt%, and the H2SO4 content is 30-50 wt%; the stirring speed is 500-1000 rpm; The molar ratio of 2,5-dimethyl-2,5-hexanediol, H2O2 and H2SO4 is 1:4-8:2-3; The temperature of the heat preservation reaction is 20-35°C, the first setting temperature is 35°C, and the second setting temperature is 20°C.

7. The production method according to claim 4 or 6, characterized in that In step (2), the set time of the insulation reaction is 20 to 40 minutes; the rotation speed of the centrifuge is 1000 to 1200 rpm, and the delay time for opening the centrifuge feed valve or the reactor discharge valve is 20 to 30 seconds.

8. The production method according to claim 4, characterized in that In step (3), the setting value of the reactor weighing module is 3 kg, and the centrifugation time is 20 to 25 minutes; In step (4), the delay time for opening the spray water valve is 10 to 15 seconds, the spraying time is 2 to 3 minutes, and the centrifugation time is 10 to 15 minutes; In step (5), the spraying time is 2 to 3 minutes, and the centrifugation time is 10 to 15 minutes.

9. The production method according to claim 4, characterized in that In step (6), the qualified index of the online pH meter is ≥3.

10. The production method according to claim 4, characterized in that The content of 2,5-dimethyl-2,5-dihydroperoxyhexane in the product is 75-85 wt %; The acidity of the product is ≤0.1%.

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