Method for producing microcapsule type environment-friendly bactericide through continuous flow

Abstract

The invention discloses a method for continuous flow production of a microcapsule type environment-friendly bactericide, which adopts low-toxicity quaternary ammonium salt as a bactericidal core material, realizes continuous synthesis of the quaternary ammonium salt by using a microchannel reactor, and prepares a finished product through a refined natural polymer microcapsule embedding process. The product disclosed by the invention is widely applied to multiple scenes such as industrial disinfection, public facility protection, object surface bacteriostasis, water body treatment and epidemic prevention, and effectively solves the technical problems that the traditional intermittent production efficiency is low, the bactericide performance stability is poor and the like.

Description

Technical Field

[0001] This invention relates to the field of organic synthesis technology, and in particular to a method for continuous flow production of microcapsule-type environmentally friendly bactericides. Background Technology

[0002] Quaternary ammonium salts, as cationic surfactants, are widely used in detergents, bactericides, and metal corrosion inhibitors. Their traditional synthesis methods mainly involve reacting long-chain aliphatic tertiary amines with alkylating agents, but these methods have several limitations. Firstly, conventional quaternary ammonium salt bactericide preparation processes utilize traditional batch reactors, resulting in long reaction cycles, low efficiency, and high safety risks. Secondly, quaternary ammonium salt bactericides that are not microencapsulated are generally difficult to effectively and persistently inactivate bacteria, and their environmental friendliness and stability are significantly reduced when directly exposed to air.

[0003] Currently, batch reactors are commonly used to synthesize quaternary ammonium salt bactericides. CN118177194A discloses a polyetheramine-modified quaternary ammonium salt bactericide and its preparation method, and CN120698887A discloses a method for synthesizing an asymmetric bis-quaternary ammonium salt bactericide. Both optimize the synthesis process of quaternary ammonium salt bactericides, but they both use batch reactors with stirring, resulting in low reaction efficiency and long reaction times. Microchannel reactors, on the other hand, possess high precision and pressure stability, enabling continuous and precise control and significantly enhanced process transfer. Furthermore, due to their inherent safety and excellent controllability, they can greatly improve the operability of the ethylene oxide / propylene oxide ring-opening polymerization process.

[0004] Currently, the process of microencapsulated bactericides has drawbacks such as residual solvents affecting biocompatibility and difficulty in scaling up. CN120345583A discloses a bactericide for oily wastewater treatment and its preparation method, which uses dichloromethane as a solvent, which may lead to residual solvents affecting biocompatibility. The use of ultrasonic emulsification process will result in uneven thickness of the microcapsule wall material, making it difficult to scale up. Summary of the Invention In view of the shortcomings of the prior art, the technical problem solved by the present invention is to provide a method for continuous flow production of microcapsule-type environmentally friendly bactericides with good treatment effect. This method for continuous flow production of microcapsule-type environmentally friendly bactericides can effectively utilize waste gas containing chemical components and achieve safe emission standards.

[0005] To solve the above-mentioned technical problems, the present invention provides a method for continuous production of microcapsule-type environmentally friendly bactericides, comprising the following two steps: Step (1), continuously synthesizing quaternary ammonium salt core material using a microchannel reactor; Step (2), encapsulating microcapsules using refined natural polymer materials; The quaternary ammonium salt core material is selected from the following structures:

[0006] R1, R2, and R3 are three alkyl groups attached to the N atom in the quaternary ammonium ion: R1 is an alkyl group containing 10 to 16 carbons; R2 is an alkyl group containing 1 to 11 carbons; R3 is an alkyl group containing 1 to 3 carbons; R4 is an alkyl group containing 1 to 5 carbons, a hydroxyl alkyl group, or a polyfunctional hydrocarbon group containing a carboxyl group; n is 0.2 to 5.0 (the average addition number of propylene oxide), and m is 1.0 to 5.0 (the average addition number of ethylene oxide). As a preferred embodiment of the above technical solution, the method for continuous flow production of microencapsulated environmentally friendly bactericides provided by the present invention further includes some or all of the following technical features: As an improvement to the above technical solution, the specific process steps of the method are as follows: (1) After mixing the tertiary amine with the solvent, organic acid is added by continuous metering. After the feeding is completed, a mixture is obtained. Then, this mixture and propylene oxide are fed into the microchannel reactor as two streams to generate reaction solution S1. Then, reaction solution S1 and ethylene oxide are added into the microchannel reactor as two streams to finally obtain quaternary ammonium salt core material. (2) Quaternary ammonium salt core material and chitosan acetate solution are continuously added to the mixing reactor according to the process ratio and fully mixed to a uniform state at the preset stirring speed. Then, the mixture is continuously transported to the emulsification unit by the metering pump, and sodium alginate solution is simultaneously pumped in according to the ratio to complete the emulsification treatment. The emulsified material is continuously fed into the solidification reaction tank through the pipeline, and calcium chloride-trisodium citrate mixture is pumped in according to the ratio through the metering system to carry out the solidification reaction. The solidified material is transported to the centrifuge for solid-liquid separation. The separated wet material enters the continuous washing system and is washed countercurrently with deionized water. Finally, the washed material is sent to the disc vacuum dryer to obtain the microcapsule bactericide.

[0007] As an improvement to the above technical solution, in step (1), the tertiary amine is one or a mixture of coconut oil-based dimethyl tertiary amine, didecyl methylamine, and N,N-di(undecyl)methylamine, the solvent is one or a mixture of propylene glycol, isopropanol, and ethylene glycol, and the organic acid is one or a mixture of lactic acid, acetic acid, and citric acid. The continuous metering feed flow rate of the organic acid in step (1) is 10-200 L / h.

[0008] As an improvement to the above technical solution, in step (1), the flow rate of the mixture is 10-200 L / h, the flow rate of propylene oxide is 1-20 L / h, the molar ratio of the mixture to propylene oxide is 1:(0.2-5.0), the reaction pressure is 0.1-0.5 MPa, the reaction temperature is 60-80℃, and the reaction time is 0.5-1h.

[0009] As an improvement to the above technical solution, in step (1), the flow rate of reaction liquid S1 is 10-200 L / h, the flow rate of ethylene oxide is 1-20 L / h, the molar ratio of reaction liquid S1 to ethylene oxide is 1:(1.0-5.0), the reaction pressure is 0.1-0.5 MPa, the reaction temperature is 60-80℃, and the reaction time is 0.5-1h.

[0010] As an improvement to the above technical solution, in step (2), the concentration of the chitosan acetate solution is 1.0%-1.5%, the core-to-wall ratio is 1:2-1:3, and the stirring speed is 200-300 r / min.

[0011] As an improvement to the above technical solution, in step (2), the continuous feed flow rate of the mixed liquid is 50-500 L / h, the continuous feed flow rate of the sodium alginate solution is 50-500 L / h, and the continuous feed flow rate of the calcium chloride-trisodium citrate mixed liquid is 50-500 L / h.

[0012] As an improvement to the above technical solution, in step (2), the concentration of sodium alginate solution is 0.8-1.2%, the stirring speed is 500-600 r / min, the emulsification time is 30-60 min, and the centrifuge speed is 3000-8000 r / min.

[0013] As an improvement to the above technical solution, in step (2), the concentration of the calcium chloride-trisodium citrate mixture is 0.3-0.5%, the curing time is 30-50 min, and the vacuum drying temperature is 40-60℃.

[0014] The present invention also includes a continuous flow production microcapsule-type environmentally friendly bactericide, which is prepared by any of the above methods and has a bactericidal rate of 99.5%-99.9% against Helicobacter pylori and a bactericidal rate of 99.3%-99.9% against Candida albicans.

[0015] This invention combines microchannel technology with chitosan wall material microcapsules to effectively solve the inherent defects of traditional quaternary ammonium salt bactericides: First, the efficacy is significantly improved, with the physical barrier of the wall material enabling controlled release and preventing rapid loss of active ingredients; second, stability is greatly enhanced, effectively isolating external factors such as air and moisture to prevent the decomposition of quaternary ammonium salts while improving dispersibility; third, environmental safety is particularly outstanding, using biodegradable wall materials to reduce the risk of environmental residues, and the controlled release mechanism also reduces the volatilization and loss of active ingredients; fourth, it is suitable for large-scale production, and can work efficiently with continuous flow microchannel reactors, further improving encapsulation efficiency and product uniformity through precise microchannel control.

[0016] Compared with the prior art, the technical solution of the present invention has the following beneficial effects: The present invention provides a method for preparing a microcapsule-type environmentally friendly bactericide through continuous flow production. This method can achieve continuous and stable synthesis of quaternary ammonium salts and precisely control the particle size, thereby achieving long-term sustained release of the bactericide and effectively improving the environmental friendliness, efficacy, and stability of the product.

[0017] (1) The present invention uses a microchannel reactor. The tertiary amine and organic acid are mixed first, and then propylene oxide / ethylene oxide are introduced into the microchannel reactor as two materials to react. By controlling the reaction temperature and reaction pressure, the reaction efficiency is significantly improved and the reaction time is shortened. At the same time, the reaction is green and safe, the process is simple, easy to control in practice, and the reaction is more efficient.

[0018] (2) This invention utilizes a natural polymer wall material composed of chitosan and sodium alginate to precisely encapsulate a low-toxicity quaternary ammonium salt bactericidal core material. This involves advanced processes such as precise core-wall ratio, three-stage emulsification and size control, and stepwise cross-linking and curing, successfully preparing a microcapsule-type bactericide. On the one hand, this technology, combined with a microchannel continuous flow reaction system, achieves continuous and stable synthesis of the quaternary ammonium salt core material; on the other hand, through the physical barrier and slow-release regulation function of the wall material, the particle size of the microcapsules is precisely controlled, ensuring slow release. This technology not only achieves continuous and stable synthesis of quaternary ammonium salts but also significantly improves the long-lasting slow-release performance of the bactericide, enhancing the product's environmental friendliness, efficacy, and stability.

[0019] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of the present invention more apparent and understandable, the following detailed description is provided in conjunction with preferred embodiments. Attached Figure Description

[0020] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings of the embodiments will be briefly described below.

[0021] Figure 1 The infrared spectrum of the coconut oil-based dimethyl hydroxypropyl hydroxyethyl lactate quaternary ammonium salt core material prepared in Example 1 is shown. Detailed Implementation

[0022] The following detailed description of specific embodiments of the present invention is part of this specification. The principles of the present invention are illustrated through examples, and other aspects, features and advantages of the present invention will become apparent from this detailed description.

[0023] Example 1 1. Microchannel continuous synthesis of quaternary ammonium salt core materials 121.5 kg of coconut oil-based dimethyl tertiary amine was mixed with 47.1 kg of isopropanol, and 49.5 kg of lactic acid was pumped in at a rate of 86 L / h to obtain a mixture. The mixture and 14.5 kg of propylene oxide were introduced into a microchannel reactor as two separate streams. The mixture was mixed at the inlet of the microchannel reactor, with the flow rate of the mixture controlled at 46.5 L / h and the flow rate of propylene oxide at 3.5 L / h. The reaction was carried out at 70 °C for 60 min at a reaction pressure of 0.3 MPa, and the reaction solution S1 was collected from the outlet of the microchannel reactor. Reaction solution S1 and 52.8 kg of ethylene oxide were introduced into a microchannel reactor as two separate streams. The mixture was homogenized at the inlet of the reactor. The flow rate of the reaction solution was controlled at 60.2 L / h, and the flow rate of ethylene oxide at 14.8 L / h. The reaction was carried out at 70℃ for 30 min at a pressure of 0.3 MPa. A coconut oil-based dimethyl hydroxypropyl hydroxyethyl lactate quaternary ammonium salt core material was obtained from the outlet of the microchannel reactor. Its molecular formula is (C... 14 CH2N(CH3)2(CH2CH(CH3)O) 0.5 (CH2CH2O) 2.5 H) + CH3CH(OH)COO .

[0024] Figure 1 The infrared spectrum of the coconut oil-based dimethyl hydroxypropyl hydroxyethyl lactate quaternary ammonium salt core material prepared in Example 1 shows the hydroxyl-OH stretching vibration peak at 3388.98 cm⁻¹. -1 The alkyl-CH3-CH2- stretching vibration peak is located at 2920.48 cm⁻¹. -1 The alkyl-CH3-CH2- symmetric stretching vibration peak is located at 2855.12 cm⁻¹. -1 The asymmetric stretching vibration peak of the carboxyl-COO- group is located at 1573.14 cm⁻¹. -1 CN + The stretching vibration peak is located at 1466.07 cm. -1 The -CH3 bending vibration peak is located at 1399.92 cm⁻¹. -1 The CO stretching vibration peak is located at 1091.72 cm⁻¹. -1 The CO bond vibration peak between the hydroxyl group and the lactate group is located at 1043.85 cm⁻¹. -1 .

[0025] 2. Refined microcapsule preparation 280 kg of coconut oil-based dimethyl hydroxypropyl hydroxyethyl lactate quaternary ammonium salt core material and 300 L of 1% chitosan acetate solution (containing 3 kg chitosan, 3 L acetic acid, and the remainder deionized water) were added to a reactor and mixed at 300 rpm for 30 min to obtain a homogeneous mixture. Then, 200 L of 1.5% sodium alginate solution (containing 3 kg sodium alginate, with deionized water) was slowly added to the mixture, and stirring was continued at 800 rpm for 10 min. The mixture was then transferred to a high-speed shear emulsifier and emulsified for 20 min to obtain an emulsion. Next, 500 L of a calcium chloride-trisodium citrate mixture (containing 25 kg calcium chloride and 5 kg trisodium citrate, with deionized water) was pumped in at a rate of 500 L / h. After the feeding was completed, stirring was continued for 30 min to solidify the mixture, forming a microcapsule suspension. The solidified suspension was centrifuged at 6000 rpm for 10 min, the supernatant was discarded, and the lower layer of microcapsules was collected. The microcapsules were washed three times with deionized water (500 L of water added each time, stirred thoroughly, and centrifuged at 3000 rpm for 10 min) until the pH of the washing solution was neutral. Finally, the washed microcapsules were dried at 50℃ and -0.09 MPa for 6 h, then ground and passed through an 80-mesh sieve to obtain a white powdery microcapsule bactericide. The product yield was 98.5%.

[0026] Example 2 1. Microchannel continuous synthesis of quaternary ammonium salt core materials 170.0 kg of didecylmethylamine and 79.9 kg of propylene glycol were mixed, and 44.8 kg of acetic acid was pumped in at a rate of 115 L / h to obtain a mixture. This mixture, along with 19.3 kg of propylene oxide, was introduced into a microchannel reactor as two separate streams. The mixture was mixed at the inlet, with the flow rate of the mixture controlled at 62.0 L / h and the flow rate of propylene oxide at 4.7 L / h. The reaction was carried out at 72℃ and 0.35 MPa, and the reaction solution S1 was collected from the outlet of the microchannel reactor. Reaction solution S1 was then introduced into the microchannel reactor as two separate streams, and mixed at the inlet. The flow rate of reaction solution S1 was controlled at 80.3 L / h and the flow rate of ethylene oxide at 19.7 L / h. The reaction was carried out at 72℃ and 0.35 MPa, and the resulting product, a quaternary ammonium salt core material of didecylmethylhydroxypropylhydroxyethylacetic acid, was obtained from the outlet of the microchannel reactor. Its molecular formula is ((C 10 H 21 )2N(CH3) (CH2CH(CH3)O) 0.6 (CH2CH2O) 2.9 H) + CH3COO .

[0027] 2. Refined microcapsule preparation 375 kg of diecrylmethylhydroxypropylhydroxyethylacetic acid quaternary ammonium salt core material and 450 L of 1% chitosan acetate solution (containing 4.5 kg chitosan, 4.5 L acetic acid, and the remainder deionized water) were added to a reactor and mixed at 300 rpm for 30 min to obtain a homogeneous mixture. Then, 300 L of 1.5% sodium alginate solution (containing 4.5 kg sodium alginate, with deionized water as the solvent) was slowly added to the mixture, and stirring was continued at 800 rpm for 10 min. The mixture was then transferred to a high-speed shear emulsifier and emulsified for 22 min to obtain an emulsion. Next, 750 L of a calcium chloride-trisodium citrate mixture (containing 37.5 kg calcium chloride and 7.5 kg trisodium citrate, with deionized water as the solvent) was slowly pumped in at a rate of 600 L / h. After the feeding was completed, stirring was continued for 30 min to solidify the mixture, forming a microcapsule suspension. The solidified suspension was centrifuged at 6000 rpm for 12 min, the supernatant was discarded, and the lower layer of microcapsules was collected. The microcapsules were washed three times with deionized water (750 L of water added each time, stirred thoroughly, and centrifuged at 3000 rpm for 12 min) until the pH of the washing solution was neutral. Finally, the washed microcapsules were dried at 52℃ and -0.09 MPa for 6.5 h, then ground and passed through an 80-mesh sieve to obtain a white powdery microcapsule bactericide. The product yield was 98.3%.

[0028] Example 3 1. Microchannel continuous synthesis of quaternary ammonium salt core materials 111.5 kg of N,N-di(undecyl)methylamine was mixed with 38.9 kg of ethylene glycol, and 84.5 kg of citric acid was pumped in at a rate of 69 L / h to obtain a mixture. This mixture, along with 11.6 kg of propylene oxide, was introduced into a microchannel reactor as two separate streams. The mixtures were mixed at the inlet, with the flow rates of the mixture and propylene oxide controlled at 37.2 L / h and 2.8 L / h, respectively. The reaction was carried out at 68 °C and 0.28 MPa. The reaction solution S1 was collected from the outlet of the microchannel reactor. Reaction solution S1 and 42.2 kg of ethylene oxide were introduced into a microchannel reactor as two separate streams and mixed at the inlet. The flow rate of reaction solution S1 was controlled at 48.2 L / h, and the flow rate of ethylene oxide at 11.8 L / h. The reaction was carried out at 68 °C and 0.28 MPa. The resulting core material, bis(undecyl)methylhydroxypropylhydroxyethyl citrate quaternary ammonium salt, was obtained from the outlet of the microchannel reactor. Its molecular formula is ((C 11 H 23)2N(CH3) (CH2CH(CH3)O) 0.7 (CH2CH2O) 2.8 H) + C6H7O7 .

[0029] 2. Refined microcapsule preparation 225 kg of quaternary ammonium salt core material and 240 L of 1% chitosan-acetic acid solution (containing 2.4 kg chitosan, 2.4 L acetic acid, and the remainder deionized water) were added to a reactor and mixed at 300 rpm for 30 min to obtain a homogeneous mixture. Then, 160 L of 1.5% sodium alginate solution (containing 2.4 kg sodium alginate, with deionized water as the solvent) was slowly added to the mixture, and stirring was continued at 800 rpm for 10 min. The mixture was then transferred to a high-speed shear emulsifier and emulsified for 18 min to obtain an emulsion. Next, 400 L of a calcium chloride-trisodium citrate mixture (containing 20 kg calcium chloride, 4 kg trisodium citrate, with deionized water as the solvent) was slowly pumped in at a rate of 400 L / h. After the feeding was completed, stirring was continued for 30 min to solidify the mixture, forming a microcapsule suspension. The solidified suspension was centrifuged at 6000 rpm for 8 min, the supernatant was discarded, and the lower layer of microcapsules was collected. The microcapsules were washed three times with deionized water (400 L of water added each time, stirred thoroughly, and centrifuged at 3000 rpm for 8 min) until the pH of the washing solution was neutral. Finally, the washed microcapsules were dried at 48℃ and -0.09 MPa for 5.5 h, then ground and passed through an 80-mesh sieve to obtain a white powdery microcapsule bactericide. The product yield was 97.5%.

[0030] Activated Helicobacter pylori and Candida albicans were transferred to Erlenmeyer flasks containing suitable culture medium and placed in a microaerophilic, constant-temperature shaking incubator at 37°C for 24 hours for activation. Subsequently, the bacterial suspension was serially diluted with broth to adjust the concentration to 1×10⁻⁶. 7 CFU / mL, aliquoted and stored for later use.

[0031] Prepare a 1% (w / w) dilution of the target bactericide. Measure 9.0 mL of the 1% dilution and place it in a sterile Petri dish. Then add 1.0 mL of the prepared bacterial suspension and mix gently. Immediately pour in 90 mL of nutrient agar medium pre-cooled to 45°C and quickly shake the Petri dish to mix the system evenly.

[0032] After the culture medium solidifies naturally, the petri dishes are inverted and placed in a 37°C microaerophilic culture environment for 48 hours. At the same time, a blank control group is set up, which uses an equal volume of deionized water to replace the bactericide dilution solution, and the rest of the operation is the same as the experimental group.

[0033] Control group 2 consisted of commercially available quaternary ammonium salt bactericides.

[0034] After the culture was completed, the average number of colony-forming units in each group of petri dishes was counted, and the sterilization rate was calculated according to the formula: sterilization rate (%) = (1 - number of colonies in the experimental group / number of colonies in the blank control group) × 100%.

[0035]

[0036] The bactericide prepared by this invention exhibits highly efficient and stable bactericidal performance against both Helicobacter pylori and Candida albicans: in Examples 1-3, the bactericidal rate against Helicobacter pylori reaches 99.5%-99.9%, and the bactericidal rate against Candida albicans also reaches 99.3%-99.9%, with excellent overall bactericidal effect.

[0037] The comparison shows that the bactericidal effect of deionized water is significantly lower (47.8% bactericidal rate against Helicobacter pylori and 54.2% against Candida albicans), indicating that a bactericidal system with a single active ingredient is difficult to achieve ideal disinfection efficacy. The bactericidal rate of control group 2 (commercially available bactericide) against the two bacteria (95.2% and 96.1%) is also significantly lower than that of the bactericide of the present invention, further demonstrating the advantages of the process and formula of the present invention in bactericidal efficacy, which can effectively meet the disinfection needs of scenarios related to Helicobacter pylori and Candida albicans.

[0038] This invention uses low-toxicity quaternary ammonium salts as the core bactericidal material, and utilizes a microchannel reactor to achieve continuous synthesis of quaternary ammonium salts. The finished product is prepared through a refined natural polymer microcapsule encapsulation process. This invention's product is widely used in various scenarios such as industrial disinfection, public facility protection, surface antibacterial treatment, water treatment, and epidemic prevention, effectively solving technical problems such as low efficiency and poor performance stability of traditional intermittent production methods.

[0039] All the raw materials listed in this invention, as well as the upper and lower limits and ranges of the raw materials and the upper and lower limits and ranges of the process parameters (such as temperature, time, etc.), can realize this invention. Examples are not listed one by one here.

[0040] The above description is merely a preferred embodiment of the present invention, and should not be construed as limiting the scope of the invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A method for continuous flow production of microencapsulated environmentally friendly bactericides, characterized in that, The process includes the following two steps: Step (1) continuous synthesis of quaternary ammonium salt core material using a microchannel reactor; Step (2) microencapsulation using refined natural polymer materials. The quaternary ammonium salt core material is selected from the following structures: R1, R2, and R3 are three alkyl groups attached to the N atom in the quaternary ammonium ion: R1 is an alkyl group containing 10 to 16 carbons; R2 is an alkyl group containing 1 to 11 carbons; R3 is an alkyl group containing 1 to 3 carbons; R4 is an alkyl group containing 1 to 5 carbons, a hydroxyalkyl group, or a polyfunctional hydrocarbon group containing a carboxyl group; n is 0.2 to 5.0, and m is 1.0 to 5.

0.

2. The method for continuous flow production of microencapsulated environmentally friendly bactericides as described in claim 2, characterized in that, The specific process steps of the method are as follows: (1) After mixing the tertiary amine with the solvent, organic acid is added by continuous metering. After the feeding is completed, a mixture is obtained. Then, this mixture and propylene oxide are fed into the microchannel reactor as two streams to generate reaction solution S1. Then, reaction solution S1 and ethylene oxide are added into the microchannel reactor as two streams to finally obtain quaternary ammonium salt core material. (2) Quaternary ammonium salt core material and chitosan acetate solution are continuously added to the mixing reactor according to the process ratio and fully mixed to a uniform state at the preset stirring speed. Then, the mixture is continuously transported to the emulsification unit by the metering pump, and sodium alginate solution is simultaneously pumped in according to the ratio to complete the emulsification treatment. The emulsified material is continuously fed into the solidification reaction tank through the pipeline, and calcium chloride-trisodium citrate mixture is pumped in according to the ratio through the metering system to carry out the solidification reaction. The solidified material is transported to the centrifuge for solid-liquid separation. The separated wet material enters the continuous washing system and is washed countercurrently with deionized water. Finally, the washed material is sent to the disc vacuum dryer to obtain the microcapsule bactericide.

3. The method for continuous flow production of microencapsulated environmentally friendly bactericides as described in claim 2, characterized in that: In step (1), the tertiary amine is one or a mixture of coconut oil-based dimethyl tertiary amine, didecyl methylamine, and N,N-di(undecyl) methylamine; the solvent is one or a mixture of propylene glycol, isopropanol, and ethylene glycol; the organic acid is one or a mixture of lactic acid, acetic acid, and citric acid; and the continuous metering feed flow rate of the organic acid in step (1) is 10-200 L / h.

4. The method for continuous flow production of microencapsulated environmentally friendly bactericides as described in claim 2, characterized in that: In step (1), the flow rate of the mixture is 10-200 L / h, the flow rate of propylene oxide is 1-20 L / h, the molar ratio of the mixture to propylene oxide is 1:(0.2-5.0), the reaction pressure is 0.1-0.5 MPa, the reaction temperature is 60-80℃, and the reaction time is 0.5-1h.

5. The method for continuous flow production of microencapsulated environmentally friendly bactericides as described in claim 2, characterized in that: In step (1), the flow rate of reaction liquid S1 is 10-200 L / h, the flow rate of ethylene oxide is 1-20 L / h, the molar ratio of reaction liquid S1 to ethylene oxide is 1:(1.0-5.0), the reaction pressure is 0.1-0.5 MPa, the reaction temperature is 60-80℃, and the reaction time is 0.5-1h.

6. The method for continuous flow production of microencapsulated environmentally friendly bactericides as described in claim 2, characterized in that: In step (2), the concentration of the chitosan acetate solution is 1.0%-1.5%, the core-to-wall ratio is 1:2-1:3, and the stirring speed is 200-300 r / min.

7. The method for continuous flow production of microencapsulated environmentally friendly bactericides as described in claim 2, characterized in that: In step (2), the continuous feed flow rate of the mixture is 50-500 L / h, the continuous feed flow rate of the sodium alginate solution is 50-500 L / h, and the continuous feed flow rate of the calcium chloride-trisodium citrate mixture is 50-500 L / h.

8. The method for continuous flow production of microencapsulated environmentally friendly bactericides as described in claim 2, characterized in that: In step (2), the concentration of sodium alginate solution is 0.8-1.2%, the stirring speed is 500-600 r / min, the emulsification time is 30-60 min, and the centrifuge speed is 3000-8000 r / min.

9. The method for continuous flow production of microencapsulated environmentally friendly bactericides as described in claim 2, characterized in that: In step (2), the concentration of the calcium chloride-trisodium citrate mixture is 0.3-0.5%, the curing time is 30-50 min, and the vacuum drying temperature is 40-60℃.

10. A continuous flow production microencapsulated environmentally friendly bactericide, characterized in that: The bactericide is prepared by any one of the methods of claims 1-9, and has a bactericidal rate of 99.5%-99.9% against Helicobacter pylori and a bactericidal rate of 99.3%-99.9% against Candida albicans.

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