Temperature-controllable sleeve type ultrasonic reactor and application method thereof

Abstract

The invention provides a temperature-controllable sleeve type ultrasonic reactor and an application method thereof. The sleeve type ultrasonic reactor comprises an ultrasonic assembly and a reaction assembly mounted on an ultrasonic radiation surface of the ultrasonic assembly, the reaction assembly comprises an inner pipe and an outer pipe which form a sleeve structure, a reaction substance can circulate in a cavity between the inner pipe and the outer pipe, and a heat exchange medium can circulate in the inner pipe. Through the nested heat exchange channel, efficient heat exchange between the reaction area and the heat exchange medium is achieved, the problem that the temperature of a traditional ultrasonic microreactor is difficult to control is solved, and the ultrasonic microreactor is particularly suitable for treatment of thermosensitive substances. The reaction assembly is designed into an inner pipe and an outer pipe which form a sleeve structure, and the space utilization rate is remarkably improved through the design of a cavity annular reaction channel between the inner pipe and the outer pipe. The casing pipe type structure does not weaken the cavitation intensity. The cavitation bubble cloud forms stable rotary motion in the annular area, and the cavitation bubble cloud is uniformly distributed; and the problem of exponential decay of a traditional amplitude-change pole type reactor is avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of chemical reaction devices, in particular to a tubular flow-through ultrasonic reaction device. Background Art

[0002] Ultrasonic cavitation is a physical phenomenon that occurs when liquids are exposed to strong ultrasonic waves. During the negative pressure half-cycle of the sound wave, the liquid is partially "torn" to form tiny cavities (cavitation bubbles) filled with gas or vapor. During the positive pressure half-cycle, these cavitation bubbles rapidly collapse and dissipate. The moment of bubble collapse generates extremely high temperatures (thousands of degrees Celsius), high pressures (over a thousand atmospheres), intense shock waves, and high-speed microjets within a tiny space. This intense energy release is the core mechanism behind applications such as ultrasonic cleaning, emulsification, cell disruption, and sonochemistry.

[0003] Traditional ultrasonic reaction systems are designed around ultrasonic horns. These cavitation reactors directly contact the ultrasonic horn with the reaction liquid to produce ultrasonic cavitation. While the cavitation intensity is high, the energy distribution decays exponentially, resulting in a significant energy gradient and severely uneven cavitation distribution within the reaction system. Furthermore, the metal probe directly contacts the reaction liquid, and cavitation can contaminate the reaction liquid with tiny metal particles. These devices also struggle to achieve temperature control, potentially leading to the inactivation of heat-sensitive substances.

[0004] In addition, in the field of chemical engineering, although there are ultrasonic reaction systems that remove the ultrasonic horn and instead use an ultrasonic transducer combined with a reactor for design and application, such as Chinese patent CN 212348692 U, which discloses an ultrasonic homogenization single-tube reactor, it uses an ultrasonic transducer combined with a reactor for design and adds a heat exchange jacket to solve the ultrasonic horn contamination and temperature control problems of traditional ultrasonic reaction systems. However, such equipment still has problems such as low ultrasonic cavitation intensity and uneven cavitation distribution in the reaction system. In addition, the ultrasonic reactor designed based on the Langevin ultrasonic transducer connects the Langevin ultrasonic transducer to the reaction device. The transducer drives the entire reaction device to vibrate, thereby generating a cavitation effect in the reaction liquid. The combination of ultrasonic cavitation and microreactor effectively prevents micron-level flow channel blockage and has great advantages in fluid mixing. However, microfluidic chips are also difficult to achieve temperature control, and their flow rate is usually low, making it difficult to meet the needs of industrial scale-up. At the same time, the micron-sized flow channel has a significant limiting effect on ultrasonic cavitation, and the ultrasonic cavitation intensity is low, which performs poorly in application scenarios such as emulsification that require high ultrasonic power density. Summary of the Invention

[0005] The purpose of the present invention is to provide a temperature-controllable sleeve-type ultrasonic reactor and an application method thereof, so as to solve the technical problems existing in the above-mentioned background technology.

[0006] The technical solution adopted by the present invention is as follows: a temperature-controllable sleeve-type ultrasonic reactor includes an ultrasonic component and a reaction component installed on the ultrasonic radiation surface of the ultrasonic component; the reaction component includes an inner tube and an outer tube forming a sleeve structure, a cavity between the inner tube and the outer tube can flow a reaction substance, and the inner tube can flow a heat exchange medium.

[0007] This invention utilizes nested heat exchange channels (a glass inner tube carries the heat exchange fluid, while an outer tube annular gap carries the reaction fluid) to achieve efficient heat exchange between the reaction zone and the heat exchange medium. This solves the temperature control difficulties of traditional ultrasonic microreactors and is particularly suitable for processing heat-sensitive substances. By designing the reaction assembly as a tube-in-tube structure with inner and outer tubes, the annular reaction channel between the inner and outer tubes significantly improves space utilization. The tube-in-tube structure does not weaken cavitation intensity. The cavitation bubble cloud forms a stable rotational motion within the annular region, resulting in a uniform distribution of the cavitation bubble cloud, thus avoiding the exponential decay problem of traditional horn-type reactors.

[0008] Further preferably, the inner diameter of the outer tube is 4mm-11mm, and the gap size between the inner tube and the outer tube is 1mm-3mm. This preferred solution is to avoid cavitation attenuation caused by the confinement effect; and experiments have confirmed that when the inner diameter of the outer tube is 4-11mm, the cavitation intensity per unit volume reaches the saturation upper limit. The gap size between the inner tube and the outer tube is required to be greater than 1mm. If it is less than 1mm, a significant confinement effect will occur (because the space is too small, an effective ultrasonic cavitation effect cannot be generated). Under the premise of a gap greater than 1mm, further increase in the gap will not affect the cavitation intensity, while an excessively large gap will lead to a deterioration in the heat exchange effect. Considering heat exchange, the gap is preferably less than 3mm.

[0009] More preferably, both ends of the outer tube are connected to multiple tubes. By designing the two ends of the outer tube to be connected to the multiple tubes, it is convenient for multiple reactants to enter the reaction area at the same time.

[0010] Further preferably, the connection between the multi-way pipe and the outer pipe is detachable. By designing the connection between the multi-way pipe and the outer pipe to be detachable, the inspection and maintenance of the outer pipe and other parts of the sleeve-type ultrasonic reactor equipment are convenient.

[0011] Further preferably, the above-mentioned sleeve-type ultrasonic reactor also includes a thin tube extending from one end of the multi-way tube into the middle of the cavity between the inner tube and the outer tube, and the discharge port of the thin tube is located in the middle of the outer tube in the direction of the reaction material inlet.

[0012] The capillary tube design allows for a more diverse feeding pattern for the tubular ultrasonic reactor, facilitating the entry of substances like ozone and oil into the reaction zone. The capillary tube's outlet is located in the center of the outer tube, toward the inlet of the reactants. This facilitates the use of acoustic flow to extend the residence time of bubbles of substances like ozone, ensuring a more complete reaction.

[0013] Further preferably, the above-mentioned sleeve-type ultrasonic reactor further includes a flexible member annularly installed between the inner wall of the multi-way pipe port and the outer wall of the inner pipe.

[0014] The present invention directly bonds the rough bottom surface of the outer tube and the ultrasonic radiation surface of the ultrasonic transducer together with ultrasonic-specific AB glue. Therefore, a flexible member such as a silicone tube is directly installed in a ring shape between the inner wall of the multi-way tube port and the outer wall of the inner tube between the inner tube and the outer tube, thereby effectively damping and sealing the ultrasonic vibration, preventing the ultrasonic vibration from being directly and rigidly transmitted to the heat exchange inner tube, and preventing the reaction system from leaking.

[0015] Further preferably, the inner and outer tubes of the telescopic ultrasonic reactor are made of glass or food-grade silicone. The all-glass / food-grade silicone contact material eliminates contamination caused by metal cavitation and meets the high purity requirements of fields such as food and medicine.

[0016] Based on the same technical idea, the present invention also provides another temperature-controllable sleeve-type ultrasonic reactor, which is composed of the above-mentioned sleeve-type ultrasonic reactors connected in series; the reaction material in the cavity between the inner tube and the outer tube enters the reactant inlet end of the latter sleeve-type ultrasonic reactor from the reactant outlet end of the previous sleeve-type ultrasonic reactor.

[0017] The present invention experimentally verified that, at different theoretical residence times, all dimensionless residence time distribution curves, obtained after a two-step normalization process, were highly consistent. This indicates that the inherent geometry of the device and the flow effects induced by ultrasound within it are the primary factors determining its fluid dynamics, while variations in macroscopic flow rate have minimal impact on these microscopic mixing characteristics. This demonstrates that mixing conditions within the reactor can remain essentially consistent across different production scales; this stability has important guiding implications for reactor design and scale-up. Based on this theory, the present invention achieves amplification by connecting multiple telescopic ultrasonic reactors in series.

[0018] Based on the same technical idea, the present invention also provides an application method of a temperature-controllable sleeve-type ultrasonic reactor, which controls the flow rate of the reaction substances in the reaction assembly of the sleeve-type ultrasonic reactor so that the residence time during the circulation process is controlled to 25-35s.

[0019] By measuring the conductivity of chloroform degradation, converting the chloride ion yield, and calculating the cavitation intensity and cavitation efficiency, the residence time with the highest cavitation efficiency in the sleeve-type ultrasonic reactor was obtained. By increasing the flow rate and shortening the residence time to 30s, a more ideal total cavitation efficiency can be achieved.

[0020] Based on the same technical idea, the present invention also provides an application method of a temperature-controllable sleeve-type ultrasonic reactor, in which the above-mentioned sleeve-type ultrasonic reactor is applied to the ozone synergistic degradation of wastewater; the ozone enters from a thin tube extending from one port of the multi-way tube into the middle of the cavity between the inner tube and the outer tube, and the wastewater enters from the port of the multi-way tube.

[0021] Based on the same technical concept, the present invention also provides a method for applying a temperature-controllable tubular ultrasonic reactor. The tubular ultrasonic reactor is used to prepare an oil-containing nanoemulsion. The oil phase is directly injected into the ultrasonic action zone via a capillary tube extending from one end of the multi-way tube into the cavity between the inner and outer tubes. Because the tubular ultrasonic reactor of the present invention has a relatively high specific ultrasonic intensity, it can be used to prepare oil-containing nanoemulsions.

[0022] Compared with the prior art, the present invention has the following beneficial effects: (1) The present invention significantly improves space utilization by designing the reaction assembly into an inner tube and an outer tube that form a sleeve structure. The annular reaction channel design of the cavity between the inner tube and the outer tube not only does not weaken the cavitation intensity, but also the cavitation bubble cloud forms a stable rotational motion in the annular area, and the cavitation bubble cloud is evenly distributed, making the cavitation reaction operation area of ​​the sleeve-type ultrasonic reactor more uniform, avoiding the exponential attenuation problem of the traditional amplitude-variable rod reactor. The present invention realizes efficient heat exchange between the reaction zone and the heat exchange medium through a nested heat exchange channel (the glass inner tube passes the heat exchange liquid, and the outer tube annular gap passes the reaction liquid), thereby solving the problem of difficult temperature control of the traditional ultrasonic microreactor, and is particularly suitable for the treatment of heat-sensitive substances; (2) The present invention has experimentally verified that under different theoretical residence times, all the dimensionless residence time distribution curves obtained after two-step normalization processing are highly coincident, which means that the inherent geometric structure of the equipment and the flow effect induced by ultrasound in it are the main factors determining its fluid dynamics behavior, and the change of macroscopic flow rate has little effect on this microscopic mixing characteristic. It shows that under different production scales, the mixing conditions inside the reactor can remain basically consistent; this stability has important guiding significance for reactor design and scale-up. Based on this theory, the present invention can achieve amplification effect by using multiple above-mentioned sleeve-type ultrasonic reactors in series; (3) The present invention measures the conductivity of chloroform degradation, converts the chloride ion yield, and calculates the cavitation intensity and cavitation efficiency. The residence time with the highest cavitation efficiency of the sleeve-type ultrasonic reactor is obtained. By increasing the flow rate and shortening the residence time to 30s, a relatively ideal total cavitation efficiency can be achieved. (4) The present invention further designs a thin tube in the sleeve-type ultrasonic reactor, extending from one end of the multi-way tube into the middle of the cavity between the inner tube and the outer tube. The discharge port of the thin tube is located in the middle of the outer tube, in the direction of the inlet of the reactants. The acoustic flow direction is used to extend the bubble residence time, thereby enhancing the mass transfer and degradation efficiency. In the nanoemulsion preparation method, ultrasonic waves act directly on the oil phase inlet, achieving the preparation of VE emulsions with low PDI (<0.2) and high encapsulation efficiency (>84%). This also verifies the applicability of the sleeve-type ultrasonic reactor of the present invention in high power density scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 Schematic diagram of the structural design of the temperature-controllable tubular ultrasonic reactor in Example 1; Figure 2 Schematic diagram of the structural design of the temperature-controllable tubular ultrasonic reactor in Example 2; Figure 3 High-speed camera observations of cavitation behavior in the reaction channel of an ultrasonic reactor, including (A) the motion mode of cavitation bubble cloud in a sleeve-type ultrasonic reactor and (B) the motion mode of cavitation bubble cloud in a straight-tube ultrasonic reactor with an inner diameter of 10 mm. Figure 4 (A) Comparison of chloride ion concentrations produced after chloroform degradation in straight tubular ultrasonic reactors with tube diameters of 1–11 mm. (B) Comparison of chloride ion yields after chloroform degradation in straight tubular ultrasonic reactors with tube diameters of 1–11 mm. Figure 5 (A) Comparison of chloride ion concentrations after degradation of chloroform in tubular-tube (TIT) and straight-tube (ST) ultrasonic reactors at different residence times. (B) Comparison of chloride ion yields after degradation of chloroform in tubular-tube (TIT) and straight-tube (ST) ultrasonic reactors at different residence times. Figure 6 (A) Original curve of residence time distribution of tubular ultrasonic reactor, (B) Dimensionless residence time distribution of tubular ultrasonic reactor; Figure 7 High-speed camera images showing the effect of the ozone gas inlet position on the direction of bubble movement. (A) shows the gas inlet located in the front half of the pipe, with the middle section of the channel as the boundary; (B) shows the gas inlet located in the back half of the pipe, with the middle section of the channel as the boundary. Figure 8 is the graph showing the degradation rate of Rhodamine B versus residence time; Figure 9This is the particle size test result of emulsions prepared under different water-oil ratios.

[0024] The numbers in the figure are: 1, ultrasonic component; 2, reaction component; 21, inner tube; 22, outer tube; 23, cavity; 3, multi-way tube; 4, thin tube; 5, flexible part; 6, reactant outlet end; 7, reactant inlet end. DETAILED DESCRIPTION

[0025] In order to facilitate understanding of the present invention, the specific embodiments of the present invention are described in further detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0026] In the description of the present invention, it should be understood that the terms "up", "down", "left", "right", "top", "bottom", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0027] Unless otherwise defined, all technical terms used hereinafter have the same meanings as those generally understood by those skilled in the art. The technical terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the scope of protection of the present invention.

[0028] Example 1 A temperature-controllable tubular ultrasonic reactor: Figure 1 As shown, it includes an ultrasonic component 1 and a reaction component 2 installed on the ultrasonic radiation surface of the ultrasonic component 1; the ultrasonic component 1 is a 20kHz Langevin type ultrasonic transducer; the reaction component 2 includes an inner tube 21 and an outer tube 22 forming a sleeve structure, and the cavity 23 between the inner tube 21 and the outer tube 22 can flow the reaction material, and the inner tube 21 can flow the heat exchange medium.

[0029] In this embodiment, the inner tube 21 is a straight hollow glass tube with an outer diameter of 5 mm, an inner diameter of 3 mm, a wall thickness of 1 mm, and a length of 170 mm. The outer tube 22 is a straight hollow glass tube with an outer diameter of 16 mm, an inner diameter of 10 mm, a wall thickness of 3 mm, and a length of 66 mm. The bottom surface, where it is bonded to the ultrasonic transducer, is polished to a rough surface 8 mm wide. The rough bottom surface of the outer glass tube is directly bonded to the ultrasonic transducer using a special ultrasonic AB adhesive.

[0030] In this embodiment, a multi-way pipe 3 is connected to each end of the outer tube 22. A four-way joint is connected to the inlet of the glass outer tube, and a three-way joint is connected to the outlet, which are sealed and fixed by sealing silicone grease.

[0031] In this embodiment, a thin tube 4 is further included, extending from one end of the multi-way tube 3 into the middle of the cavity 23 between the inner tube 21 and the outer tube 22. The discharge port 41 of the thin tube 4 is located in the middle of the outer tube 22, toward the inlet of the reactants. Of course, if multiple feeding methods are not required, this component can be deleted.

[0032] In this embodiment, a flexible member 5 is further included, which is a silicone tube installed in a ring shape between the inner wall of the port of the multi-way tube 3 and the outer wall of the inner tube 21.

[0033] Example 2 A temperature-controllable tubular ultrasonic reactor: Figure 2 As shown, the two telescopic ultrasonic reactors in Example 1 are connected in series; the reaction material in the cavity 23 between the inner tube 21 and the outer tube 22 enters the reactant inlet 7 of the latter telescopic ultrasonic reactor from the reactant outlet 6 of the former telescopic ultrasonic reactor.

[0034] During use, the 20kHz Langevin ultrasonic transducer of ultrasonic assembly 1 is activated, and the reactants enter reaction assembly 2 through multi-way tube 3 for reaction. In some cases, some reactants need to enter reaction assembly 2 through capillary tube 4 for reaction. After the reactants react in the first telescopic ultrasonic reactor, the reaction products are discharged from the reactant outlet 6 of the first telescopic ultrasonic reactor. After passing through a U-shaped tube, they enter the next reaction assembly through the reactant inlet 7 of the second telescopic ultrasonic reactor for reaction. The two reactors are connected by a U-shaped tube, mainly to facilitate the fixed support of the inner and outer tubes and prevent the pipes from being too long and breaking due to the lack of stress points.

[0035] Example 3 If an inner tube is not inserted into an outer tube, it does not constitute a telescopic ultrasonic reactor and is referred to as a "straight-tube ultrasonic reactor" in the present invention. To investigate the performance of the telescopic ultrasonic reactor of the present invention, this example compares the telescopic ultrasonic reactor of Example 1 with a "straight-tube ultrasonic reactor." The following describes straight-tube ultrasonic reactors with different tube diameters. The tube diameter in the straight-tube ultrasonic reactor is analogous to the inner diameter of the outer tube of the telescopic ultrasonic reactor.

[0036] 1. Comparison of the movement patterns of cavitation bubble clouds generated by sleeve-type and straight-tube ultrasonic reactors: Under the action of the sound field, a cavitation bubble cloud will form in the area of ​​the reactor where the sound pressure amplitude is high enough. It is composed of a dense group of tiny bubbles. These bubbles expand and collapse (collapse) violently periodically with the sound waves, and release huge energy (high temperature, high pressure, shock waves, microjets) at the moment of collapse. Understanding and controlling cavitation bubble clouds are the key to effectively utilizing ultrasonic energy. The present invention uses a high-speed imaging device to observe the movement pattern of the cavitation bubble cloud in the ultrasonic reactor. The lighting part uses a green laser light source with a wavelength of 545nm, which penetrates the ultrasonic reactor channel. The cavitation bubble cloud will reflect and refract the light and emit light. The cavitation behavior in the ultrasonic reactor channel is observed and recorded by a high-speed camera ( Figure 3 ).

[0037] like Figure 3 As shown, if the viewing direction is defined as the outflow direction of the reaction liquid, the motion pattern of the cavitation bubble cloud in both the telescoped and straight-tube ultrasonic reactors exhibits counterclockwise or clockwise rotation. In repeated experiments, the frequency of counterclockwise or clockwise rotation was the same, likely due to the initial state of ultrasound activation. There were no significant differences in the spatial distribution and motion pattern of the cavitation bubble cloud between the telescoped and straight-tube ultrasonic reactors, indicating that inserting an inner tube to form a telescoped structure does not disrupt the original cavitation pattern of the straight-tube ultrasonic reactor. Furthermore, cavitation bubbles tend to adhere to the wall of the straight-tube ultrasonic reactor, resulting in a lower density of the cavitation bubble cloud closer to the center of the channel. Therefore, the annular reaction zone of the telescoped ultrasonic reactor has a higher spatial utilization rate than the circular reaction zone. In addition, since the reaction area of ​​the sleeve-type ultrasonic reactor is a circular reaction area where cavitation bubble clouds are concentrated, compared with the situation where there is no cavitation bubble cloud in the center of the reaction tube of the straight-tube ultrasonic reactor, the cavitation reaction operation area of ​​the sleeve-type ultrasonic reactor is more uniform, avoiding the exponential attenuation of ultrasonic energy distribution in the traditional ultrasonic reaction system and the problem of obvious energy gradient.

[0038] 2. Comparison of cavitation intensity generated by tubular and straight tube ultrasonic reactors: Under the action of ultrasound, chloroform is prone to sonolysis in aqueous solution, releasing Cl2, Cl - 、ClO3 - Plasma increases the conductivity of the aqueous solution. Therefore, cavitation intensity can be assessed by monitoring the conductivity of the effluent solution after ultrasonic treatment. Inserting a conductivity meter probe into the reactor's clepsydra-like structure continuously monitors the effluent's conductivity. Once the reading stabilizes, sample the effluent's conductivity at 20 points at 10-second intervals and take the average.

[0039] Prepare 1L of 10mM chloroform solution and inject it into the ultrasonic reactor channel at a specific flow rate using a syringe pump. Set the ultrasonic power to 60W. Adjust the flow rate of the chloroform solution so that the chloroform solution has the same residence time in the sleeve ultrasonic reactor and the straight ultrasonic reactor with different tube diameters. The flow rate settings for different retention volumes and residence times are shown in Table 1.

[0040]

[0041] Calculated based on the chloride ion concentration in the solution, using the limiting molar conductivity of chloride ions ( , 25 ° C) to calculate the chloride ion concentration in the outflow solution. (μS / cm)) and chloride ion concentration ( The relationship between (μmol / mL) can be expressed as: (1).

[0042] The chloride ion concentration after chloroform degradation is calculated by formula 1, which is used to represent the cavitation intensity per unit volume in the reactor. The chloride ion concentration produced is multiplied by the flow rate to obtain the chloride ion yield within a certain period of time, which represents the total cavitation efficiency of the reactor. The measurement and calculation results are shown in the figure below. Figure 4 and Figure 5 As shown. Figure 4 (A) Chloride ion concentration after chloroform degradation in a straight tubular ultrasonic reactor with a tube diameter of 1–11 mm; (B) Chloride ion yield after chloroform degradation in a straight tubular ultrasonic reactor with a tube diameter of 1–11 mm. Figure 5 The data selected are comparative data of the sleeve-type ultrasonic reactor and the straight-tube ultrasonic reactor with an outer tube inner diameter of 10 mm, including (A) the chloride ion concentration after degradation of chloroform by the sleeve-type (TIT) and the straight-tube (ST) ultrasonic reactors at different residence times; (B) the chloride ion yield of chloroform by the sleeve-type (TIT) and the straight-tube (ST) ultrasonic reactors at different residence times.

[0043] like Figure 4 As shown in Figure (A), under residence times of 30s and 60s, the cavitation intensity generated by tubes with inner diameters of 1mm and 2mm is extremely low due to confinement. When the inner diameter reaches 3mm, the cavitation intensity increases significantly due to the sufficient compression space. From 3mm to 4mm, the increase in compressible volume further increases the cavitation intensity. However, when the inner diameter exceeds 4mm, the cavitation intensity reaches its upper limit and no longer increases with increasing tube diameter. Therefore, when setting the inner diameter of the outer tube of the ultrasonic reactor, a size greater than 4mm should be selected.

[0044] like Figure 4As shown in Figure (B), the chloride ion yield increases with increasing tube diameter. This is because, given a constant cavitation intensity per unit volume, a larger reactor can process a greater volume, resulting in higher cavitation efficiency. It should be noted that this study only collected experimental data for a straight tubular reactor with an inner diameter of 11 mm and an outer diameter of 17 mm, as further increases in diameter can easily cause the glass tube to break under ultrasonic vibration.

[0045] Figure 5 The results show the chloride ion concentration produced by the degradation of chloroform by the sleeve-type and straight-tube ultrasonic reactors with an outer tube inner diameter of 10 mm at different residence times, as well as the chloride ion yield of the sleeve-type and straight-tube ultrasonic reactors at different residence times. Figure 5 As shown in (A), there is no significant difference in cavitation intensity between the straight tube type and the sleeve type ultrasonic reactor with the same outer tube inner diameter of 10 mm, indicating that nesting a cooling inner tube in the center of the reaction channel does not affect the cavitation intensity of the reactor. Figure 5 As shown in Figures (A) and (B), both the tubular and straight ultrasonic reactors exhibit varying cavitation intensities as the residence time of the reactants changes. At a residence time of 60 s, the cavitation intensity per unit volume is nearly twice that of a residence time of 30 s; however, the cavitation efficiency is higher at a residence time of 30 s. This indicates that increasing the flow rate significantly decreases the cavitation intensity when the residence time decreases from 60 s to 30 s, but significantly improves the cavitation efficiency. As the flow rate increases, the residence time decreases from 120 s to 30 s, and the cavitation efficiency continues to improve, indicating that the increase in flow rate has a greater impact on cavitation efficiency than the decrease in cavitation intensity. However, when the residence time is shortened to 15 s, the trend reverses, with the highest cavitation efficiency occurring at a residence time of 30 s. This suggests that there is a balance between the effects of cavitation intensity and flow rate on cavitation efficiency; exceeding this balance point is detrimental to achieving optimal cavitation efficiency. The experimental data above show that cavitation efficiency is highest when the flow rate is controlled at a residence time of 30 s. Therefore, when using the sleeve-type ultrasonic reactor of the present invention to carry out the reaction, it is the best solution to control the flow rate of the reaction materials in the reaction assembly of the sleeve-type ultrasonic reactor so that the residence time during the circulation process is controlled to 30s. Figure 5 As shown in Figure B, the cavitation efficiency of the straight-tube ultrasonic reactor is higher than that of the sleeve-tube ultrasonic reactor. This is because when the inner diameter of the outer tube is 10 mm, the straight-tube ultrasonic reactor has a larger reaction retention volume. Therefore, at the same residence time, the cavitation efficiency is higher than that of the sleeve-tube ultrasonic reactor. When the reaction retention volume of the ultrasonic reactors is the same, the cavitation efficiency of the sleeve-tube and straight-tube ultrasonic reactors is the same because the cavitation intensity is the same.

[0046] 3. Residence time distribution and scalability investigation: In order to test the hydrodynamic performance of the tubular ultrasonic reactor, the residence time distribution of the tubular ultrasonic reactor under different theoretical residence times was tested by the pulse tracer method. At time 0, 0.2 mL of saturated potassium chloride (KCl) solution (conductivity of about 200 mS / cm) was instantaneously injected, and the conductivity-time curve was recorded at the outlet. . Figure 7 The tracer KCl concentration at the reactor outlet is shown at different theoretical residence times. The raw response curve over time, where Figure 6 (A) Original residence time distribution curve of a tubular ultrasonic reactor; (B) Dimensionless residence time distribution of a tubular ultrasonic reactor.

[0047] like Figure 6 As shown in (A), each curve exhibits a clear single peak, indicating effective diffusion and mixing of the tracer within the reactor. The average residence time of the original response curve is consistent with expectations and is essentially equivalent to the theoretical residence time.

[0048] In order to compare the mixing and dispersion characteristics of the fluid inside the double-tube ultrasonic reactor at different residence times, the original tracer concentration curve A two-step normalization process was performed to obtain the dimensionless residence time distribution function Normalizing the concentration axis, we get . Indicates that among all the fluid elements flowing through the reactor, the residence time is and The probability density of the fluid between is as follows: (2).

[0049] Normalized The curve satisfies: .

[0050] Normalize the time axis dimensionlessly to get We will time Convert to dimensionless time ,in Here Under each experimental condition, The actual average residence time calculated from the curve is: (3).

[0051] Correspondingly, the dimensionless residence time distribution function and The relationship is: (4).

[0052] dimensionless The curve meets the following conditions: .

[0053] Figure 6 (B) shows the dimensionless residence time distribution curve obtained after the above two-step normalization process at different theoretical residence times. All curves are highly consistent, indicating that the inherent geometry of the device and the ultrasound-induced flow effects are the primary factors determining its fluid dynamics, while changes in the macroscopic flow rate have little effect on the microscopic mixing characteristics. This stability is of great significance for reactor design and scale-up, demonstrating that mixing conditions within the reactor can remain essentially consistent at different production scales.

[0054] Therefore, the present invention designed a telescopic ultrasonic reactor in Example 2. It connects two telescopic ultrasonic reactors in Example 1 in series, allowing the reactants in the cavity between the inner and outer tubes to enter the reactant inlet of the next telescopic ultrasonic reactor from the reactant outlet of the previous telescopic ultrasonic reactor. Using multiple telescopic ultrasonic reactors in series can achieve cumulative amplification of ultrasonic cavitation intensity. Serial amplification of tubular ultrasonic reactors is equivalent to increasing the ultrasonic action length (equivalent to extending the tube). For example, if two reactors are connected in series: 1. If the original flow rate is maintained, the residence time under ultrasound is doubled, which can be considered a direct doubling of the ultrasonic intensity. This manifests as greater degradation in degradation and as smaller particle size emulsification in emulsification. 2. If the residence time under ultrasound is maintained, the flow rate is doubled. Therefore, the cavitation intensity remains unchanged, but the flow rate (yield) is doubled.

[0055] Example 4 A method for applying a temperature-controllable tubular ultrasonic reactor (using a tubular ultrasonic reactor to promote ozone degradation of rhodamine B).

[0056] Rhodamine B (RhB) is a widely used dye, and its wastewater discharge poses a serious threat to the environment. Ozone (O3) is a strong oxidant and is widely used in water treatment. However, its low solubility in water and poor stability limit its mass transfer efficiency, resulting in a relatively low mineralization rate for pollutants. To overcome these shortcomings, attempts have been made to combine ozone oxidation with other technologies. Ultrasound (US) technology, through its unique acoustic cavitation effect, not only generates free radicals by decomposing water but also significantly improves the mass transfer process, providing a new approach to enhance the degradation capacity of ozone. Therefore, the ultrasound-assisted ozone (US / O3) system is considered an effective strategy for treating refractory organic pollutants such as RhB.

[0057] like Figure 2 As shown, the series-connected tubular ultrasonic reactors of Example 2 were used. By positioning the ozone inlet within the ultrasonic action zone, the ozone gas was dispersed into small bubbles under the action of ultrasound upon entering the Rhodamine B solution, thereby enhancing the diffusion and dissolution of the ozone gas in the Rhodamine B solution. The flow rates of the Rhodamine B solution were set to 3.53 mL / min, 7.06 mL / min, and 14.12 mL / min, with residence times in the reactor of 60 s, 30 s, and 15 s, respectively.

[0058] The movement of ozone bubbles after entering the ultrasonic reactor was observed and recorded by a high-speed camera. Figure 7 As shown in A, with the middle section of the channel as the boundary, the gas inlet is located in the front half of the pipeline, and the ozone bubbles move against the flow direction of the Rhodamine B solution. Due to the extended residence time of the ozone bubbles in the Rhodamine B solution, they are dispersed. Figure 7 As shown in Figure B, with the middle section of the channel as the boundary, the gas inlet is located in the latter half of the pipeline, and the ozone bubbles move along the flow direction of the Rhodamine B solution, which is not conducive to extending the residence time and dispersion of the ozone bubbles in the Rhodamine B solution.

[0059] Figure 8 The comparison of the degradation rate of Rhodamine B at different residence times is shown. Figure 8 It can be seen that as the flow rate of rhodamine B solution decreased from 14.12 to 4.71 mL / min and the residence time increased from 15 s to 60 s, the degradation rate of rhodamine B increased from 33% to 66%.

[0060] Example 5 The invention discloses an application method of a temperature-controllable sleeve-type ultrasonic reactor (using the sleeve-type ultrasonic reactor to prepare VE-encapsulated soybean oil nanoemulsion).

[0061] Vitamin E (VE) is a fat-soluble nutrient and potent antioxidant that plays a crucial role in maintaining cell membrane integrity, combating oxidative stress, and preventing a variety of chronic diseases. However, its inherent hydrophobicity, chemical instability (susceptibility to light, heat, and oxygen), and poor gastrointestinal absorption significantly limit its bioavailability and efficacy in food, pharmaceutical, and cosmetic applications. To overcome these challenges, designing efficient delivery systems is crucial. Soybean oil, a naturally occurring plant oil with abundant resources, nutritional balance, and excellent biocompatibility, is not only a good solvent for VE but also contains VE itself. Encapsulating VE in soybean oil-based emulsions is a promising strategy. VE-encapsulated soybean oil nanoemulsions not only effectively protect and stabilize VE but also utilize the lipid's digestive and absorption pathways to significantly enhance VE's oral and topical bioavailability, while also endowing the product with excellent physical properties and potential for application.

[0062] When preparing oil-in-water (O / W) nanoemulsions, soybean oil containing 1.6% vitamin E was used as the oil phase; deionized water containing 6% surfactant was used as the aqueous phase, where the surfactant consisted of 28% Span 80 and 72% Tween 80, making its HLB value equal to 12.

[0063] During the specific operation, the oil phase extends from one end of the multi-way tube into the thin tube in the middle of the cavity between the inner tube and the outer tube and is directly injected into the ultrasonic action area. The oil phase inlet is located in the front half of the pipeline, with the middle section of the channel as the boundary. By setting the oil phase feed port to the ultrasonic action area, the oil phase is dispersed into fine oil droplets under the action of ultrasound as soon as it enters the water phase, thereby enhancing its diffusion in the water phase. Different water-oil ratios were set, the total flow rate was maintained at 3.53 mL / min, and the residence time in the reactor was 60s. The properties of the prepared emulsion, the average droplet particle size (DS) and the polydispersity index (PDI) were as follows: Figure 9 shown.

[0064] from Figure 9 As can be seen, at water-to-oil ratios (A / O) of 5 / 1, 9 / 1, 12 / 1, 15 / 1, and 19 / 1, the emulsion droplet size decreases with increasing A / O ratio, and the PDI is less than 0.2. Liquid chromatography determined the VE yields at these different A / O ratios to be 84.2%, 87.4%, 86.2%, 90.1%, and 89.7%, respectively.

[0065] The above embodiments merely represent one or more embodiments of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of protection of the present invention. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present invention, and such modifications and improvements fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be subject to the appended claims.

Claims

1. A temperature-controllable tubular ultrasonic reactor, characterized in that: The invention comprises an ultrasonic component (1) and a reaction component (2) mounted on the ultrasonic radiation surface of the ultrasonic component; the reaction component (2) comprises an inner tube (21) and an outer tube (22) forming a sleeve structure; a cavity (23) between the inner tube (21) and the outer tube (22) can flow a reaction substance, and the inner tube (21) can flow a heat exchange medium.

2. The sleeve-type ultrasonic reactor according to claim 1, characterized in that: The inner diameter of the outer tube (22) is 4 mm to 11 mm, and the gap size between the inner tube (21) and the outer tube (22) is 1 mm to 3 mm.

3. The sleeve-type ultrasonic reactor according to claim 2, characterized in that: Multi-way pipes (3) are respectively connected to both ends of the outer tube (22).

4. The sleeve-type ultrasonic reactor according to claim 3, characterized in that: It also includes a thin tube (4) extending from one end of the multi-way tube (3) into the middle of the cavity (23) between the inner tube (21) and the outer tube (22), and the discharge port (41) of the thin tube (4) is located in the middle of the outer tube (22) and in the direction of the reaction material inlet.

5. The sleeve-type ultrasonic reactor according to claim 4, characterized in that: It also includes a flexible member (5) annularly installed between the inner wall of the port of the multi-way pipe (3) and the outer wall of the inner pipe (21).

6. The sleeve-type ultrasonic reactor according to claim 5, characterized in that: The inner tube (21) and the outer tube (22) are made of glass or food-grade silica gel.

7. A temperature-controllable tubular ultrasonic reactor, characterized in that: The invention is composed of the sleeve-type ultrasonic reactors according to any one of claims 1 to 6 connected in series; the reaction material in the cavity (23) between the inner tube (21) and the outer tube (22) enters the reactant inlet (7) of the latter sleeve-type ultrasonic reactor from the reactant outlet (6) of the former sleeve-type ultrasonic reactor.

8. An application method of a temperature-controllable tubular ultrasonic reactor, characterized in that: The reaction material in the reaction assembly of the sleeve-type ultrasonic reactor according to any one of claims 1 to 6 is flow-controlled so that the residence time during the circulation process is controlled to be 25-35 seconds.

9. An application method of a temperature-controllable tubular ultrasonic reactor, characterized in that: The sleeve-type ultrasonic reactor according to any one of claims 4 to 6 is applied to the ozone synergistic degradation of wastewater; the ozone enters through a thin tube extending from one port of the multi-way tube into the middle of the cavity between the inner tube and the outer tube, and the wastewater enters through the port of the multi-way tube.

10. An application method of a temperature-controllable tubular ultrasonic reactor, characterized in that: The sleeve-type ultrasonic reactor according to any one of claims 4 to 6 is applied to the preparation of nanoemulsion, wherein the nanoemulsion is an oil-containing nanoemulsion, and the oil phase is directly injected into the ultrasonic action zone through a thin tube extending from one end of the multi-way tube into the middle of the cavity between the inner tube and the outer tube.

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