A rotary evaporation device with accurate weighing

Abstract

The application discloses a rotary evaporation device with accurate weighing, which comprises a water bath pot, a bottom plate, a mounting frame, a collecting bottle, a condenser, a head motor, and a rotary bottle. The mounting frame is mounted on the bottom plate, the collecting bottle is mounted on the mounting frame, the condenser is arranged above the collecting bottle and connected to the outlet of the collecting bottle, the condenser is provided with an air inlet and a connecting port for connecting the rotary bottle, the head motor is arranged at the connecting port of the condenser, and the bottle opening of the rotary bottle is connected with the output shaft of the head motor, so that the steam in the rotary bottle can enter the condenser through the connecting port. The rotary bottle is a glass bottle with a weight of 15 g, and the water bath pot is arranged below the rotary bottle and used for heating the rotary bottle.

Description

Technical Field

[0001] This application relates to the field of rotary evaporators, and more specifically to a rotary evaporator device with accurate weighing. Background Technology

[0002] For some high-value organic compounds, the yield is low, only a few tens of milligrams. Therefore, minimizing transfer losses and ensuring accurate weighing are extremely important. To address transfer losses, rotary evaporation should be used to collect the compounds in the next reaction vessel whenever possible, eliminating the need for transfer and thus avoiding losses during the transfer process.

[0003] For accurate weighing, rotary evaporation is required for collection, and the rotating flasks used in the collection process are usually round-bottom flasks or pear-shaped flasks. The smallest size of a round-bottom flask or pear-shaped flask is 10ml, weighing about 35g. Collecting tens of mg of product in a 35g rotating flask results in a relatively large error, the balance has a weak ability to resolve "small increments in the sample", and the error between two weighings is relatively large. Summary of the Invention

[0004] To achieve the above and other related objectives, this application discloses a rotary evaporator with accurate weighing, comprising a water bath, a base plate, a mounting frame, a collecting bottle, a condenser, a head motor, and a rotating bottle. The mounting frame is mounted on the base plate, the collecting bottle is mounted on the mounting frame, the condenser is positioned above the collecting bottle and connected to the outlet of the collecting bottle, the condenser has an air inlet and a connection port for connecting the rotating bottle, the head motor is positioned at the connection port of the condenser, and the mouth of the rotating bottle is connected to the output shaft of the head motor, so that the steam in the rotating bottle can enter the condenser through the connection port. The rotating bottle is a glass bottle weighing 15g, and the water bath is positioned below the rotating bottle for heating the rotating bottle.

[0005] Preferably, it also includes a speed control box, which is wired to the head motor and is used to adjust the speed of the head motor.

[0006] Preferably, the water bath is equipped with a control box for controlling the temperature of the water bath.

[0007] Preferably, the mounting bracket is detachably connected to a mounting ring, the collection bottle is placed on the mounting ring, and the mounting ring clamps the collection bottle to fix the collection bottle.

[0008] Preferably, a connector is provided at the connection position between the mounting ring and the mounting bracket. The connector includes a fixing ring and a screw. The fixing ring is fixedly connected to the mounting ring and is sleeved on the mounting bracket. The screw is threadedly connected to the fixing ring. When the screw is tightened, the screw abuts against the mounting bracket to fix the position of the mounting ring.

[0009] Preferably, the rotating flask is equipped with a rubber stopper, which, when not installed on the rotary evaporator, engages with the mouth of the rotating flask to seal it.

[0010] By adopting the above technical solution, the original 35g rotating bottle was replaced with a 15g rotating bottle, thereby reducing the error generated when weighing the sample and improving the accuracy of weighing the sample. Attached Figure Description

[0011] The above and other features, advantages, and aspects of the embodiments of this disclosure will become more apparent from the accompanying drawings and the following detailed description. The drawings are provided for a better understanding of the invention and are not intended to limit the scope of this disclosure. In the drawings, the same or similar reference numerals denote the same or similar elements, wherein: Figure 1 This is a schematic diagram of an embodiment of the present invention.

[0012] Reference numerals: 1. Water bath; 2. Base plate; 3. Mounting bracket; 4. Collection bottle; 5. Condenser; 51. Air inlet; 6. Head motor; 7. Rotating bottle; 8. Speed ​​control box; 9. Control box; 10. Mounting ring; 11. Fixing ring; 12. Screw; 13. Lifting handle. Detailed Implementation

[0013] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0014] Reference Figure 1 This application provides a rotary evaporator with accurate weighing capabilities, including a water bath 1, a base plate 2, a mounting frame 3, a collection bottle 4, a condenser 5, a head motor 6, and a rotating bottle 7. The mounting frame 3 is mounted on the base plate 2, the collection bottle 4 is mounted on the mounting frame 3, the condenser 5 is positioned above the collection bottle 4 and connected to the outlet of the collection bottle 4, the condenser 5 has an air inlet 51 and a connection port for connecting the rotating bottle 7, the head motor 6 is positioned at the connection port of the condenser 5, and the bottle mouth of the rotating bottle 7 is connected to the output shaft of the head motor 6, so that the vapor in the rotating bottle 7 can enter the condenser 5 through the connection port, and the head motor 6 can drive the rotating bottle 7 to rotate. The rotating bottle 7 is a glass bottle weighing 15g, and the water bath 1 is positioned below the rotating bottle 7 for heating the rotating bottle 7.

[0015] It also includes a speed control box 8, which is wired to the head motor 6 and used to adjust the speed of the head motor 6; the water bath 1 is equipped with a control box 9 for controlling the temperature of the water bath 1. The water bath 1 is equipped with a lifting handle 13 for adjusting the height of the water bath 1. The technology of adjusting the speed of the head motor 6 through the speed control box 8 and adjusting the temperature of the water bath 1 through the control box 9 is a mature existing technology that can be implemented by those skilled in the art, and will not be described in detail here.

[0016] The mounting frame 3 is detachably connected to a mounting ring 10. The collection bottle 4 is placed on the mounting ring 10, and the mounting ring 10 clamps the collection bottle 4 to fix it. A connector is provided at the connection position between the mounting ring 10 and the mounting frame 3. The connector includes a fixing ring 11 and a screw 12. The fixing ring 11 is fixedly connected to the mounting ring 10 and is sleeved on the mounting frame 3. The screw 12 is threadedly connected to the fixing ring 11. When the screw 12 is tightened, the screw 12 abuts against the mounting frame 3 to fix the position of the mounting ring 10. The rotating bottle 7 is equipped with a rubber stopper. When not installed on the rotary evaporator, the rubber stopper is engaged with the mouth of the rotating bottle 7 to seal it.

[0017] When collecting samples of tens of mg, a 15g container is more accurate than a 35g container. The core reason is the difference in relative error during the weighing process, as analyzed in detail below: After the sample is collected in the rotating bottle 7, the sample is weighed using the "difference subtraction method". The difference subtraction method is the difference between the mass m1 of the empty rotating bottle 7 and the total mass m2 of the container + sample. The error mainly comes from the absolute error of the balance, such as ±0.1mg.

[0018] Because the absolute error of a balance is fixed: the error between two weighings will accumulate, such as ±0.2mg; Relative error = absolute error / sample mass: the smaller the relative error, the more reliable the result.

[0019] For a sample of tens of mg (taking 50 mg as an example): The total mass of the 35g container plus the sample is approximately 35.05g, with the sample accounting for only 0.14% of the total mass. The total mass of the 15g container plus the sample is approximately 15.05g, representing 0.33% of the total mass.

[0020] The higher the proportion of the sample in the total mass, the stronger the balance's ability to distinguish "this tiny increase in sample mass". The 35g container, due to its own excessive mass, weakens the "signal" of sample mass, making it more difficult for the balance to accurately capture tiny changes in total mass.

[0021] The indication error of the balance increases slightly as the weighing range increases: When weighing 35g, the maximum permissible error of the balance is higher than that when weighing 15g. For example, the maximum permissible error of the balance in the range of 20-100g is ±0.5mg, and the maximum permissible error in the range of 10-20g is ±0.2mg.

[0022] Therefore, the two weighings of the 35g container have a larger error, which leads to an increase in the error in the calculation of the sample mass. The 15g rotating bottle 7 has higher accuracy.

[0023] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A rotary evaporator with accurate weighing capability, characterized in that, The device includes a water bath, a base plate, a mounting bracket, a collection bottle, a condenser, a head motor, and a rotating bottle. The mounting bracket is mounted on the base plate, the collection bottle is mounted on the mounting bracket, the condenser is positioned above the collection bottle and connected to the collection bottle's outlet, and the condenser has an air inlet and a connection port for connecting the rotating bottle. The head motor is located at the condenser's connection port, and the mouth of the rotating bottle is connected to the output shaft of the head motor, allowing steam in the rotating bottle to enter the condenser through the connection port. The rotating bottle is a 15g glass bottle, and the water bath is positioned below the rotating bottle for heating it.

2. The rotary evaporator with accurate weighing according to claim 1, characterized in that, It also includes a speed control box, which is wired to the head motor and used to adjust the speed of the head motor.

3. The rotary evaporator with accurate weighing according to claim 1, characterized in that, The water bath is equipped with a control box for controlling the temperature of the water bath.

4. The rotary evaporator with accurate weighing according to claim 1, characterized in that, The mounting bracket is detachably connected to a mounting ring. The collection bottle is placed on the mounting ring, and the mounting ring clamps the collection bottle to fix it in place.

5. The rotary evaporator with accurate weighing according to claim 4, characterized in that, A connector is provided at the connection position between the mounting ring and the mounting bracket. The connector includes a fixing ring and a screw. The fixing ring is fixedly connected to the mounting ring and is sleeved on the mounting bracket. The screw is threadedly connected to the fixing ring. When the screw is tightened, the screw abuts against the mounting bracket to fix the position of the mounting ring.

6. The rotary evaporator with accurate weighing according to claim 1, characterized in that, The rotating flask is equipped with a rubber stopper, which, when not installed on the rotary evaporator, snaps into the mouth of the rotating flask to seal it.

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