Preparation method for preparing dibutyltin dilaurate by solvent-free method

Abstract

The invention provides a preparation method for preparing dibutyltin dilaurate through a solvent-free method, and relates to the technical field of chemical engineering. According to the preparation method of dibutyltin dilaurate, a predetermined amount of coconut oil acid and dibutyltin dichloride are obtained, the uniformity of a mixture is kept through stirring equipment, and sufficient contact of reactants is ensured; in the process of dropwise adding the sodium hydroxide solution, the reaction temperature is kept stable through a temperature control device; after the pH value is adjusted, separating out lower-layer saline water by using a separating funnel, and adjusting the separation speed and efficiency by controlling a valve to ensure thorough separation; obtaining a separated product, and heating the product in a vacuum environment; and after drying, filtering the product to obtain the final dibutyltin dilaurate. Dibutyltin dichloride and alkali liquor are used. The dibutyltin dichloride is liquid and is simple, convenient and safe to use, redundant solvents are not needed in the reaction process, safety and environmental protection are guaranteed, the dibutyltin dichloride is directly used as the raw material in the process, one-step reaction is achieved, and efficiency is improved.

Description

Technical Field

[0001] The invention relates to the technical field of chemical industry, and in particular to a method for preparing dibutyltin dilaurate by a solvent-free method. Background Art

[0002] In the relevant process, dibutyltin oxide is a toxic powder, and toluene is used as a solvent in the process, which is not safe and environmentally friendly. In the process, dibutyltin oxide is alkalized with tin chloride and dried. In the production process, dibutyltin oxide undergoes solid-liquid separation (centrifugation), drying, packaging, etc., and there is loss in each step. Summary of the invention

[0003] The invention provides a method for preparing dibutyltin dilaurate by a solvent-free method, using dibutyltin dichloride and alkali solution. Both are liquids, which are relatively simple and safe to use, and no extra solvent is needed in the reaction process, so safety and environmental protection are guaranteed. In the process, dibutyltin dichloride is directly used as a raw material, which becomes a one-step reaction and improves efficiency.

[0004] A method for preparing dibutyltin dilaurate by a solvent-free method, characterized in that the method comprises:

[0005] Obtain a predetermined amount of coconut oleic acid and dibutyltin dichloride, add them into a reaction vessel, and maintain the uniformity of the mixture by a stirring device to ensure that the reactants are fully contacted;

[0006] If the mixture is uniform, gradually add sodium hydroxide solution dropwise, using a titration device to control the rate of addition of sodium hydroxide solution to avoid a sharp increase in temperature or precipitation of reactants during the reaction;

[0007] During the process of adding the sodium hydroxide solution, the reaction temperature is maintained between 50 and 60°C by a temperature control device to ensure temperature stability;

[0008] Maintain the reaction temperature at 50-60°C for 2 hours to ensure that the reaction proceeds fully;

[0009] The pH value of the reaction system is continuously monitored by a pH meter. If the pH value deviates from 5-7, acid or base is added in time to adjust it to ensure that the pH value is maintained between 5-7;

[0010] After the pH value is adjusted, use a separatory funnel to separate the lower brine, and adjust the separation speed and efficiency by controlling the valve to ensure complete separation;

[0011] The separated product is obtained and placed in a vacuum drying device, where it is heated in a vacuum environment to remove moisture and other volatile substances;

[0012] After drying, the product is filtered to obtain the final dibutyltin dilaurate.

[0013] In some specific embodiments, a predetermined amount of coconut oleic acid and dibutyltin dichloride are obtained, added to a reaction vessel, and the uniformity of the mixture is maintained by a stirring device to ensure that the reactants are fully contacted, comprising:

[0014] Obtaining predetermined amounts of coconut oleic acid and dibutyltin dichloride;

[0015] Transfer the measured coconut oleic acid and dibutyltin dichloride into a reaction vessel;

[0016] Automatic conveying system is used to ensure continuous and stable conveying of materials;

[0017] Start the stirring equipment to maintain the homogeneity of the mixture.

[0018] In some specific embodiments, if the mixture is uniform, the sodium hydroxide solution is gradually added dropwise, and a titration device is used to control the addition rate of the sodium hydroxide solution to avoid a sharp increase in temperature or precipitation of reactants during the reaction, including:

[0019] The temperature of the reaction system is monitored by a temperature sensor to ensure that the reaction is carried out within the range of 50-60°C;

[0020] According to the temperature data, the dripping rate of the sodium hydroxide solution is adjusted through the computer control system to avoid a sharp increase in temperature;

[0021] Obtain the dripping rate data and further accurately control the amount of sodium hydroxide solution added through the flow meter;

[0022] An online pH sensor is used to monitor the pH value of the reaction system in real time;

[0023] According to the pH data, adjust the dosage of acid or alkali to control the pH value in the range of 5-7.

[0024] In some specific embodiments, during the process of adding the sodium hydroxide solution dropwise, the reaction temperature is maintained between 50-60° C. by a temperature control device to ensure temperature stability, including:

[0025] Step 1: Start the temperature monitoring module to obtain the temperature data in the reactor in real time;

[0026] The temperature monitoring module collects temperature data every 1 second through the temperature sensor installed on the wall of the reactor, and transmits the data to the central control system;

[0027] Step 2: After receiving the temperature data, the central control system performs preliminary data processing, including data cleaning and outlier removal;

[0028] Use filtering algorithms to smooth temperature data, eliminate random fluctuations, and ensure data accuracy;

[0029] Step 3: Compare the processed temperature data with the preset temperature range (50-60°C);

[0030] If the current temperature is lower than 50°C, the heating device start command is triggered;

[0031] If the current temperature is higher than 60°C, the cooling device start command is triggered;

[0032] Step 4: After receiving the command, the heating or cooling device automatically adjusts the power to achieve accurate control of the temperature in the reactor; the heating device adopts electric heating, and the cooling device adopts circulating water cooling to ensure rapid response of temperature regulation;

[0033] Step 5: During the process of adding the sodium hydroxide solution, the temperature change in the reactor is continuously monitored; the central control system dynamically adjusts the power of the heating or cooling device according to the real-time temperature data to maintain the temperature between 50-60°C;

[0034] Step 6: Record the start time and end time of adding sodium hydroxide solution, and calculate the average temperature during the adding process; generate a temperature change curve through the correspondence between timestamp and temperature data, which is convenient for subsequent analysis;

[0035] Step 7: After the addition of sodium hydroxide solution is completed, continue to monitor the temperature in the reactor to ensure that the temperature is stable during the insulation reaction stage;

[0036] The reaction time was 2 hours, during which the temperature fluctuation range was controlled within ±2°C.

[0037] In some specific embodiments, the reaction temperature is maintained at 50-60° C. for 2 hours to ensure that the reaction is fully carried out, including:

[0038] Obtain initial concentration data of dibutyltin chloride and coconut oleic acid and record them in the database;

[0039] Set up the reactor temperature control system, and set the target temperature range to 50-60°C;

[0040] Start the reactor heating device and monitor the temperature changes in real time to ensure that the temperature is stable within the set range;

[0041] Add sodium hydroxide solution to the reactor at a constant rate through a dropping device, and record the dropping speed and the amount of dropping;

[0042] Continuously monitor the temperature in the reactor. If the temperature deviates from the range of 50-60℃, the heating power will be automatically adjusted to return the temperature to the set range.

[0043] Record the reaction start time and continuously monitor the reaction progress to ensure that the reaction time reaches 2 hours;

[0044] During the reaction, the pH value data in the reactor is collected in real time. If the pH value deviates from the range of 5-7, the acid droplet acceleration rate is automatically adjusted to maintain the pH value within the target range;

[0045] After the reaction is completed, the separation device is started to separate the lower salt water layer from the upper organic phase, and the separation time and separation effect are recorded;

[0046] The separated organic phase was input into the vacuum drying device, and the drying parameters were set to ensure that the water was completely evaporated, and the drying time and drying effect were recorded.

[0047] In some specific embodiments, the pH value of the reaction system is continuously monitored by a pH meter. If the pH value deviates from 5-7, acid or base is added in time to adjust the pH value to ensure that the pH value is maintained between 5-7, including:

[0048] The pH value of the reaction system was continuously monitored by a pH meter. If the pH value deviated from 5-7, acid or base was added to adjust it in time;

[0049] Use sensors to collect current pH value data;

[0050] Based on the sensor data, determine whether the pH value needs to be adjusted;

[0051] If the pH is below 5, obtain the dosage of the acid regulator;

[0052] Acidity regulator is automatically added through computer control system;

[0053] If the pH is above 7, obtain the amount of alkaline regulator to be added.

[0054] In some specific embodiments, after the pH value is adjusted, a separatory funnel is used to separate the lower brine, and the separation speed and efficiency are adjusted by controlling a valve to ensure thorough separation, including.

[0055] In some specific embodiments, the separated product is placed in a vacuum drying device, and the product is heated under a vacuum environment to remove moisture and other volatile substances, including.

[0056] In some specific embodiments, after the drying is completed, the product is filtered to obtain the final dibutyltin dilaurate, including:

[0057] Remove moisture through vacuum drying technology to obtain a dry product;

[0058] The dried product is filtered to remove unreacted residues and impurities.

[0059] The technical solution provided by the embodiment of the present invention may have the following beneficial effects:

[0060] The invention discloses a method for preparing dibutyltin dilaurate by controlling reaction conditions. First, coconut oil acid and dibutyltin dichloride are mixed, and a stirring device is used to ensure that the reactants are in uniform contact. Subsequently, a sodium hydroxide solution is gradually added dropwise, and the addition rate is accurately controlled by a titration device to avoid a sharp increase in temperature or precipitation of reactants. During the reaction, the temperature control device stabilizes the reaction temperature at 50-60°C, and the reaction is continued for 2 hours to ensure sufficient reaction. At the same time, a pH meter monitors the pH value of the reaction system in real time. If it deviates from the range of 5-7, it is adjusted by adding acid or alkali to ensure the stability of the reaction environment. After the reaction is completed, a separatory funnel is used to separate the lower layer of brine to ensure complete separation. Finally, the separated product is vacuum dried to remove moisture and volatile substances, and high-purity dibutyltin dilaurate is obtained after filtration. The invention ensures high purity and high yield of the product by accurately controlling the reaction conditions, and has high industrial application value. The dibutyltin dilaurate method uses dibutyltin dichloride and alkali solution. They are all liquids, which are relatively simple and safe to use. No extra solvent is needed in the reaction process, so safety and environmental protection are guaranteed. Dibutyltin dichloride is directly used as the raw material in the process, which becomes a one-step reaction and improves efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] Figure 1 The present invention is a flow chart of a method for preparing dibutyltin dilaurate by a solvent-free method. DETAILED DESCRIPTION

[0062] In order to further understand the content of the present invention, the present invention is described in detail in conjunction with the accompanying drawings and embodiments. The present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It is understood that the specific embodiments described herein are only used to explain the relevant inventions, rather than to limit the invention. It is also necessary to explain that, for ease of description, only the parts related to the invention are shown in the accompanying drawings.

[0063] like Figure 1 In this embodiment, a solvent-free method for preparing dibutyltin dilaurate may specifically include:

[0064] Step S101, obtaining a predetermined amount of coconut oleic acid and dibutyltin dichloride, adding them into a reaction container, and maintaining the uniformity of the mixture by a stirring device to ensure that the reactants are fully contacted.

[0065] Obtain the predetermined amount of coconut oleic acid and dibutyltin dichloride. Transfer the measured coconut oleic acid and dibutyltin dichloride to the reaction vessel. Use an automatic conveying system to ensure continuous and stable conveying of the materials. Start the stirring device to maintain the uniformity of the mixture.

[0066] Specifically, in the chemical reaction process of preparing coconut oleic acid and dibutyltin dichloride, it is first necessary to accurately calculate the required ratio of coconut oleic acid and dibutyltin dichloride. The measured coconut oleic acid and dibutyltin dichloride are transported to the reaction vessel through a conveying system to ensure the continuous and stable transportation of the materials and avoid material blockage or waste during the transportation process. The reaction vessel is equipped with an efficient stirring device, which automatically adjusts the stirring speed and time according to the viscosity and density of the materials to ensure that the mixture is evenly mixed throughout the reaction process. The stirring speed is set to 500 rpm and stirred for 30 minutes to promote the complete reaction. Through this series of precisely controlled steps, the chemical reaction of coconut oleic acid and dibutyltin dichloride can be efficiently completed to prepare the desired product.

[0067] Step S102, if the mixture is uniform, gradually add sodium hydroxide solution dropwise, and use a titration device to control the addition rate of the sodium hydroxide solution to avoid a sharp increase in temperature or precipitation of reactants during the reaction.

[0068] The temperature of the reaction system is monitored by a temperature sensor to ensure that the reaction is carried out within the range of 50-60°C. According to the temperature data, the dripping rate of the sodium hydroxide solution is adjusted through the computer control system to avoid a sharp increase in temperature. The dripping rate data is obtained and the amount of sodium hydroxide solution added is further accurately controlled through the flow meter. The pH value of the reaction system is monitored in real time using an online pH sensor. According to the pH data, the amount of acid or alkali added is adjusted to control the pH value in the range of 5-7.

[0069] Specifically, during the chemical reaction, the temperature of the system is monitored in real time by a temperature sensor. When the temperature reaches 50°C, the computer control system begins to adjust the drip rate of the sodium hydroxide solution through an algorithm to ensure that the temperature is stable between 50-60°C. For example, if the temperature sensor detects that the temperature rises to 55°C, the control system will reduce the drip rate by 5 ml per minute to prevent the temperature from being too high. At the same time, the flow meter will accurately record the actual amount of sodium hydroxide solution added and feed the data back to the control system for the next adjustment. In terms of pH control, the real-time online pH sensor monitors the pH value of the reaction system. When the pH value rises to 5, the computer control system will automatically calculate how much acid solution needs to be added to adjust the pH value to the ideal range of 5-7. For example, if the current pH value is 5, the system may decide to add 10 ml of 1M hydrochloric acid to adjust the pH value. In this way, the system is able to continuously adjust and stabilize the pH value. In the product separation stage, the separation equipment automatically separates the lower brine and the upper product according to the density difference. The separation efficiency is optimized through sensor data to ensure the purity of the upper product and the recovery rate of the lower brine are maximized. Afterwards, the upper product enters the vacuum drying stage. During the drying process, the degree of dryness is monitored by a humidity sensor. When the humidity drops below the set value of 5%, the computer system determines that the product has reached the predetermined degree of dryness and automatically stops the drying process.

[0070] Step S103, during the process of adding the sodium hydroxide solution, the reaction temperature is maintained between 50-60° C. by a temperature control device to ensure temperature stability.

[0071] Step 1: Start the temperature monitoring module to obtain the temperature data in the reactor in real time. The temperature monitoring module collects temperature data every 1 second through the temperature sensor installed on the wall of the reactor, and transmits the data to the central control system. Step 2: After receiving the temperature data, the central control system performs preliminary data processing, including data cleaning and outlier removal. The temperature data is smoothed by a filtering algorithm to eliminate random fluctuations and ensure the accuracy of the data. Step 3: Compare the processed temperature data with the preset temperature range (50-60℃). If the current temperature is lower than 50℃, the heating device start instruction is triggered; if the current temperature is higher than 60℃, the cooling device start instruction is triggered. Step 4: After receiving the instruction, the heating or cooling device automatically adjusts the power to achieve precise control of the temperature in the reactor. The heating device adopts electric heating and the cooling device adopts circulating water cooling to ensure rapid response of temperature regulation. Step 5: During the process of adding sodium hydroxide solution, the temperature changes in the reactor are continuously monitored. The central control system dynamically adjusts the power of the heating or cooling device according to the real-time temperature data to maintain the temperature between 50-60℃. Step 6: Record the start and end time of adding sodium hydroxide solution, and calculate the average temperature during the addition process. Generate a temperature change curve through the correspondence between timestamp and temperature data for subsequent analysis. Step 7: After the addition of sodium hydroxide solution is completed, continue to monitor the temperature in the reactor to ensure that the temperature is stable during the insulation reaction stage. The insulation reaction time is 2 hours, and the temperature fluctuation range is controlled within ±2°C during this period.

[0072] Specifically, the temperature monitoring module is started, and the temperature data is collected every 1 second through the high-precision Pt100 temperature sensor installed on the wall of the reactor, and the data is transmitted to the central control system in the form of a 4-20mA standard signal. After the central control system uses PLC (programmable logic controller) to receive the temperature data, it first performs preliminary data processing, sorts 10 consecutive data using the median filtering algorithm, takes the middle value as the valid data, removes the abnormal value, and ensures the accuracy of the data. For example, the 10 temperature data collected continuously are 45℃, 52℃, 51℃, 53℃, 50℃, 50℃, 52℃, 51℃, 54℃, and 50℃. After median filtering, 52℃ is taken as the valid data. The processed temperature data is compared with the preset temperature range (50-60℃). If the current temperature is lower than 50℃, the PLC immediately triggers the start command of the heating device, sets the electric heating power to 5kW, and heats at a rate of 1℃ per minute; if the current temperature is higher than 60℃, the start command of the cooling device is triggered, and the circulating water cooling system cools at a rate of 5℃ per minute. The heating device adopts the PID (proportional-integral-differential) control algorithm to dynamically adjust the electric heating power according to the deviation between the real-time temperature and the set temperature to ensure the accuracy of temperature control. During the process of dripping sodium hydroxide solution, the temperature monitoring module continuously collects temperature data, and the central control system receives and processes the data every second, and dynamically adjusts the power of the heating or cooling device according to the real-time temperature. For example, when the temperature drops to 48℃ during the dripping process, the PLC immediately increases the electric heating power to 6kW, so that the temperature quickly rises to above 50℃; if the temperature rises to 62℃, the cooling water flow is reduced to reduce the temperature to below 60℃, and the temperature is maintained between 50-60℃. Record the start and end time of the addition of sodium hydroxide solution. Assuming the start time is 10:00:00 and the end time is 10:30:00, calculate the average temperature during the addition process. Generate a temperature change curve through the correspondence between timestamps and temperature data for subsequent analysis. For example, a total of 1,800 temperature data points were collected during the addition process, and the average temperature was calculated to be 52°C. A temperature change curve was generated in Excel. After the addition of sodium hydroxide solution was completed, continue to monitor the temperature in the reactor to ensure that the temperature was stable during the insulation reaction stage. The insulation reaction time was 2 hours, and the temperature fluctuation range was controlled within ±2°C during the period. The PLC records the temperature data once a minute. If the temperature deviates from the range of 50-60°C, immediately adjust the power of the heating or cooling device to ensure temperature stability. For example, if the temperature drops to 48°C during the insulation process, the PLC immediately increases the electric heating power to 7kW to raise the temperature back to 50°C.

[0073] Step S104, maintaining the reaction temperature at 50-60°C and continuing the reaction for 2 hours to ensure that the reaction is fully carried out.

[0074] Obtain the initial concentration data of dibutyltin chloride and coconut oleic acid and record them in the database. Set the reactor temperature control system, and set the target temperature range to 50-60℃. Start the reactor heating device, monitor the temperature change in real time, and ensure that the temperature is stable within the set range. Add sodium hydroxide solution to the reactor at a constant rate through the dripping device, and record the dripping speed and dripping amount at the same time. Continuously monitor the temperature in the reactor. If the temperature deviates from the range of 50-60℃, automatically adjust the heating power to return the temperature to the set range. Record the start time of the reaction and continuously monitor the reaction progress to ensure that the reaction time reaches 2 hours. During the reaction, collect the pH value data in the reactor in real time. If the pH value deviates from the range of 5-7, automatically adjust the acid drop acceleration rate to maintain the pH value within the target range. After the reaction is completed, start the separation device to separate the lower brine from the upper organic phase, and record the separation time and separation effect. Input the separated organic phase into the vacuum drying device, set the drying parameters to ensure that the water is completely evaporated, and record the drying time and drying effect.

[0075] Specifically, first, the initial concentrations of dibutyltin chloride and coconut oleic acid were determined by high performance liquid chromatography (HPLC), and the concentrations of dibutyltin chloride and coconut oleic acid were measured to be 5 mol / L and 2 mol / L, respectively. These data were recorded in an SQL database with the table name "raw material concentration" and the fields including "substance name", "concentration value" and "measurement time". Next, the reactor temperature control system was set, the target temperature range was set to 50-60°C, the PID control algorithm was used, the proportional coefficient Kp was set to 2, the integral coefficient Ki was set to 5, and the differential coefficient Kd was set to 1 to ensure that the temperature control accuracy was within ±1°C. The reactor heating device was started, and the temperature change was monitored in real time using a thermocouple. The data was collected once per second and transmitted to the control system. If the temperature exceeded the set range, the system automatically adjusted the heating power. The adjustment range was calculated based on the temperature difference using the formula ΔP = Kp*ΔT+Ki*∫ΔTdt+Kd*d(ΔT) / dt. Sodium hydroxide solution is added to the reactor at a constant rate by a peristaltic pump device. The drop speed is set to 5 mL / min. The drop amount is recorded in real time. The data is updated every minute and stored in the "Drop Record" table. The fields include "Drop Time", "Drop Speed" and "Cumulative Drop Amount". The temperature in the reactor is continuously monitored. If the temperature deviates from the range of 50-60 ° C, the control system automatically adjusts the heating power according to the PID algorithm to return the temperature to the set range. The reaction start time is recorded, and the reaction process is continuously monitored using a timer to ensure that the reaction time reaches 2 hours. The reaction status is checked every 10 minutes during this period, and the data is recorded in the "Reaction Monitoring" table. During the reaction process, a pH meter is used to collect pH value data in the reactor in real time. The sampling frequency is once per minute. If the pH value deviates from the range of 5-7, the control system automatically adjusts the acid drop acceleration rate according to the deviation value. The adjustment formula is ΔV = KpH*(pH target-pH actual), where KpH is the adjustment coefficient, set to 1mL / min·pH unit, to ensure that the pH value is within the target range. After the reaction is completed, the centrifugal separation device is started, the speed is set to 3000rpm, the separation time is 15 minutes, and the separation effect is detected by the optical sensor. The transmittance is recorded in the "Separation Effect" table, and the fields include "Separation Time", "Transmittance" and "Separation Efficiency". The separated organic phase is input into the vacuum drying device, and the vacuum degree is set to 1MPa, the drying temperature is set to 60℃, and the drying time is set to 30 minutes to ensure that the water is completely evaporated. The drying effect is detected by the infrared moisture meter. The moisture content is recorded in the "Drying Record" table, and the fields include "Drying Time", "Moisture Content" and "Drying Efficiency". During the whole process, all data are collected by sensors and transmitted to the central control system, which is automatically analyzed and processed by the system to ensure the accuracy and consistency of each step of the operation, and ultimately achieve efficient and stable chemical reaction control.

[0076] Step S105, continuously monitoring the pH value of the reaction system by a pH meter, if the pH value deviates from 5-7, adding acid or alkali to adjust it in time to ensure that the pH value is maintained between 5-7.

[0077] The pH value of the reaction system is continuously monitored by a pH meter. If the pH value deviates from 5-7, acid or alkali is added in time for adjustment. The current pH value data is collected by a sensor. According to the sensor data, it is determined whether the pH value needs to be adjusted. If the pH value is lower than 5, the dosage of the acidic regulator is obtained. The acidic regulator is automatically added through the computer control system. If the pH value is higher than 7, the dosage of the alkaline regulator is obtained. The alkaline regulator is automatically added through the computer control system. The pH value is re-monitored by a sensor to confirm the stability of the pH value after adjustment. The pH value and the amount of regulator adjusted each time are recorded through the data processing system. The calculation model of the acid and alkali dosage is optimized through historical data analysis.

[0078] Specifically, in actual operation, the current pH value is first monitored in real time by the pH sensor installed in the reactor. For example, the sensor sends pH value data to the data processing system once a minute. Suppose at a certain moment, the sensor reading shows that the pH value is 8. At this time, the system determines that the pH value is lower than 5 through a preset algorithm and needs to be adjusted. The system uses a linear regression model to calculate the required amount of acid regulator based on the difference between the current pH value and the target pH value. Assume that the calculation result is 2 ml. Subsequently, the computer control system automatically activates the dosing pump and accurately adds 2 ml of acid regulator to the reactor. After addition, the system continues to monitor the change in pH until the sensor shows that the pH value is stable within the target range of 5-7, for example, stable at 5. During each adjustment process, the system records the pH value before and after the adjustment and the actual amount of adjustment added, and these data are stored for subsequent analysis.

[0079] Step S106, after the pH value adjustment is completed, the lower layer of brine is separated using a separatory funnel, and the separation speed and efficiency are adjusted by controlling the valve to ensure complete separation.

[0080] Step S107, obtaining the separated product, placing it in a vacuum drying device, and heating the product in a vacuum environment to remove moisture and other volatile substances.

[0081] Step S108, after drying is completed, the product is filtered to obtain the final dibutyltin dilaurate, and then packaged.

[0082] React dibutyltin chloride and coconut oleic acid at 50-60°C, and add sodium hydroxide solution. Keep the reaction warm for 2 hours to ensure that the reaction is fully carried out. Add acid to adjust the pH to between 5-7, and control the reaction environment by adjusting the pH value. Separate the lower brine and remove unwanted by-products through separation technology. Remove moisture through vacuum drying technology to obtain a dry product. Filter the dried product to remove unreacted residues and impurities. Package the filtered dibutyltin dilaurate using suitable packaging materials. Mark the package and record product information, including production date and batch number. Store the packaged product under appropriate temperature and humidity conditions.

[0083] Specifically, in the process of preparing dibutyltin dilaurate, dibutyltin chloride is first mixed with coconut oleic acid and reacted at a temperature of 50-60°C. In order to ensure the complete reaction, sodium hydroxide solution is gradually added dropwise to adjust the pH value to 5-7. This step is completed by real-time monitoring of the online pH meter and the automatic titration system to ensure the precise control of the reaction environment. After the reaction lasts for 2 hours, the lower layer of brine is separated by a separatory funnel. In this process, the separation is automatically completed by density difference, reducing manual intervention. Subsequently, the reaction mixture is sent to a vacuum dryer, and the vacuum degree is set to -08MPa and the temperature is controlled at 70°C to remove moisture. The moisture content during the drying process is monitored in real time by a humidity sensor to ensure the dryness of the product. The dried product passes through an automatic filtration system to remove unreacted residues and impurities, and the filtration accuracy reaches 10 microns. Finally, the filtered product is automatically packaged and encapsulated with aluminum-plastic composite materials with good moisture-proof properties. The production date and batch number are automatically printed on each packaging bag by a printer for tracking and management. The storage environment is maintained at 25°C and 50% relative humidity through an automatic temperature and humidity control system to ensure product stability and long-term storage. Throughout the process, data and operating parameters of each step are recorded and analyzed through a central control system to optimize production processes and product quality.

[0084] In this process flow, there is also a key technical contradiction, that is, how to avoid the generation of reactant precipitation while ensuring the stability of the reaction temperature during the process of dripping sodium hydroxide solution. First, the dripping rate of sodium hydroxide solution directly affects the temperature change of the reaction system. If the dripping is too fast, it may cause the local temperature to rise sharply, thereby inducing side reactions or reactant precipitation. However, if the dripping is too slow, it may cause the reaction time to be extended, affecting production efficiency. In addition, although the temperature control device can adjust the reaction temperature to a certain extent, due to the unevenness of the heat release during the reaction, the response speed of the temperature control device may not be able to keep up with the temperature change in time, resulting in large local temperature fluctuations, thereby affecting the uniformity and stability of the reaction. At the same time, there are certain technical difficulties in the regulation of pH value. Although the pH value of the reaction system can be monitored in real time by a pH meter, in actual operation, the fluctuation of pH value may be more frequent, especially in the process of dripping sodium hydroxide solution, the pH value may deviate from the target range instantly, resulting in the acid-base balance of the reaction system being broken, thereby affecting the quality of the final product. Therefore, how to ensure the stability of temperature and the precise control of pH value during the process of dripping sodium hydroxide solution is a core technical problem in this process flow.

[0085] The invention discloses a method for preparing dibutyltin dilaurate by controlling reaction conditions. First, coconut oil acid and dibutyltin dichloride are mixed, and a stirring device is used to ensure that the reactants are in uniform contact. Subsequently, a sodium hydroxide solution is gradually added dropwise, and the addition rate is accurately controlled by a titration device to avoid a sharp increase in temperature or precipitation of reactants. During the reaction, the temperature control device stabilizes the reaction temperature at 50-60°C, and the reaction is continued for 2 hours to ensure sufficient reaction. At the same time, a pH meter monitors the pH value of the reaction system in real time. If it deviates from the range of 5-7, it is adjusted by adding acid or alkali to ensure the stability of the reaction environment. After the reaction is completed, a separatory funnel is used to separate the lower layer of brine to ensure complete separation. Finally, the separated product is vacuum dried to remove moisture and volatile substances, and high-purity dibutyltin dilaurate is obtained after filtration. The invention ensures high purity and high yield of the product by accurately controlling the reaction conditions, and has high industrial application value. The dibutyltin dilaurate method uses dibutyltin dichloride and alkali solution. They are all liquids, which are relatively simple and safe to use. No extra solvent is needed in the reaction process, so safety and environmental protection are guaranteed. Dibutyltin dichloride is directly used as the raw material in the process, which becomes a one-step reaction and improves efficiency.

[0086] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A method for preparing dibutyltin dilaurate by a solvent-free method, characterized in that: The method comprises: Obtain a predetermined amount of coconut oleic acid and dibutyltin dichloride, add them into a reaction vessel, and maintain the uniformity of the mixture by a stirring device to ensure that the reactants are fully contacted; If the mixture is uniform, gradually add sodium hydroxide solution dropwise, using a titration device to control the rate of addition of sodium hydroxide solution to avoid a sharp increase in temperature or precipitation of reactants during the reaction; During the process of adding the sodium hydroxide solution, the reaction temperature is maintained between 50 and 60°C by a temperature control device to ensure temperature stability; Maintain the reaction temperature at 50-60°C for 2 hours to ensure that the reaction proceeds fully; The pH value of the reaction system is continuously monitored by a pH meter. If the pH value deviates from 5-7, acid or base is added in time to adjust it to ensure that the pH value is maintained between 5-7; After the pH value is adjusted, use a separatory funnel to separate the lower brine, and adjust the separation speed and efficiency by controlling the valve to ensure complete separation; The separated product is obtained and placed in a vacuum drying device, where it is heated in a vacuum environment to remove moisture and other volatile substances; After drying, the product is filtered to obtain the final dibutyltin dilaurate.

2. The method according to claim 1, characterized in that The method of obtaining a predetermined amount of coconut oleic acid and dibutyltin dichloride, adding the mixture to a reaction vessel, and maintaining the uniformity of the mixture by a stirring device to ensure that the reactants are fully contacted, comprises: Obtaining predetermined amounts of coconut oleic acid and dibutyltin dichloride; Transfer the measured coconut oleic acid and dibutyltin dichloride into a reaction vessel; Automatic conveying system is used to ensure continuous and stable conveying of materials; Start the stirring equipment to maintain the homogeneity of the mixture.

3. The method according to claim 1, characterized in that If the mixture is uniform, gradually add sodium hydroxide solution dropwise, and use a titration device to control the addition rate of the sodium hydroxide solution to avoid a sharp increase in temperature or precipitation of reactants during the reaction, including: The temperature of the reaction system is monitored by a temperature sensor to ensure that the reaction is carried out within the range of 50-60°C. According to the temperature data, the dropping rate of the sodium hydroxide solution is adjusted through the computer control system to avoid a sharp increase in temperature; Obtain the dripping rate data and further accurately control the amount of sodium hydroxide solution added through the flow meter; An online pH sensor is used to monitor the pH value of the reaction system in real time; According to the pH data, adjust the dosage of acid or alkali to control the pH value in the range of 5-7.

4. The method according to claim 1, characterized in that: In the process of adding the sodium hydroxide solution dropwise, the reaction temperature is maintained between 50° C. and 60° C. by a temperature control device to ensure temperature stability, including: Step 1: Start the temperature monitoring module to obtain the temperature data in the reactor in real time; The temperature monitoring module collects temperature data every 1 second through the temperature sensor installed on the wall of the reactor, and transmits the data to the central control system; Step 2: After receiving the temperature data, the central control system performs preliminary data processing, including data cleaning and outlier removal; Use filtering algorithms to smooth temperature data, eliminate random fluctuations, and ensure data accuracy; Step 3: Compare the processed temperature data with the preset temperature range (50-60°C); If the current temperature is lower than 50°C, the heating device start command is triggered; If the current temperature is higher than 60°C, the cooling device start command is triggered; Step 4: After receiving the command, the heating or cooling device automatically adjusts the power to achieve accurate control of the temperature in the reactor; the heating device adopts electric heating, and the cooling device adopts circulating water cooling to ensure rapid response of temperature regulation; Step 5: During the process of adding the sodium hydroxide solution, the temperature change in the reactor is continuously monitored; the central control system dynamically adjusts the power of the heating or cooling device according to the real-time temperature data to maintain the temperature between 50-60°C; Step 6: Record the start time and end time of adding sodium hydroxide solution, and calculate the average temperature during the adding process; generate a temperature change curve through the correspondence between timestamp and temperature data, which is convenient for subsequent analysis; Step 7: After the addition of sodium hydroxide solution is completed, continue to monitor the temperature in the reactor to ensure that the temperature is stable during the insulation reaction stage; The reaction time was 2 hours, during which the temperature fluctuation range was controlled within ±2°C.

5. The method according to claim 1, characterized in that The step of maintaining the reaction temperature at 50-60° C. for 2 hours to ensure that the reaction is fully carried out comprises: Obtain initial concentration data of dibutyltin chloride and coconut oleic acid and record them in the database; Set up the reactor temperature control system, and set the target temperature range to 50-60°C; Start the reactor heating device and monitor the temperature changes in real time to ensure that the temperature is stable within the set range; Add sodium hydroxide solution to the reactor at a constant rate through a dropping device, and record the dropping speed and the amount of dropping; Continuously monitor the temperature in the reactor. If the temperature deviates from the range of 50-60℃, the heating power will be automatically adjusted to return the temperature to the set range. Record the reaction start time and continuously monitor the reaction progress to ensure that the reaction time reaches 2 hours; During the reaction, the pH value data in the reactor is collected in real time. If the pH value deviates from the range of 5-7, the acid droplet acceleration rate is automatically adjusted to maintain the pH value within the target range; After the reaction is completed, the separation device is started to separate the lower salt water layer from the upper organic phase, and the separation time and separation effect are recorded; The separated organic phase was input into the vacuum drying device, and the drying parameters were set to ensure that the water was completely evaporated, and the drying time and drying effect were recorded.

6. The method according to claim 1, characterized in that The pH value of the reaction system is continuously monitored by a pH meter. If the pH value deviates from 5-7, acid or alkali is added in time to adjust the pH value to ensure that the pH value is maintained between 5-7, including: The pH value of the reaction system was continuously monitored by a pH meter. If the pH value deviated from 5-7, acid or base was added to adjust it in time; Use sensors to collect current pH value data; Based on the sensor data, determine whether the pH value needs to be adjusted; If the pH is below 5, obtain the dosage of the acid regulator; Acidity regulator is automatically added through computer control system; If the pH is above 7, obtain the amount of alkaline regulator to be added.

7. The method according to claim 1, characterized in that After the pH value adjustment is completed, a separatory funnel is used to separate the lower brine, and the separation speed and efficiency are adjusted by controlling the valve to ensure thorough separation, including.

8. The method according to claim 1, characterized in that: The separated product is placed in a vacuum drying device, and the product is heated under a vacuum environment to remove moisture and other volatile substances, including.

9. The method according to claim 1, characterized in that: After the drying is completed, the product is filtered to obtain the final dibutyltin dilaurate, including: Remove moisture through vacuum drying technology to obtain a dry product; The dried product is filtered to remove unreacted residues and impurities.

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