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For waste liquid, it is usually packed in a 500ml glass reagent bottle of Sinopharm, or in a 4-liter or 5-liter white plastic bucket.

It is necessary to mark on it with a marker pen that this is waste liquid, and also indicate the main components of the waste liquid.

The main components of their laboratory waste liquids are commonly used organic solvents.

If it is a strong acid, strong alkali, strong oxidizing agent, strong reducing agent, or special waste liquid such as fluorine-containing waste liquid, it is best to pre-treat it before handing it over to the waste liquid warehouse.

If it is really impossible to deal with it, you should also explain the situation to the waste liquid warehouse to prevent them from treating it as ordinary waste liquid and causing safety accidents.

After disposing of liquid waste and solid waste, the two returned to A502 again.

At this time, the color of the solution in the extraction tube of the Soxhlet extraction device is light blue.

This indicates that the extraction of the sample by the chloroform solvent is not sufficient and some time is required.

Xu Qiu was not idle either, he came to the rotary steamer to check the circulating cooling device.

It was found that only about half of the coolant inside it was left. It seems that the coolant inside has evaporated a lot and needs to be added again.

This machine should not have been turned on for almost a year. Duan Yun usually does not use rotary steaming for inorganic synthesis.

Xu Qiu added ethylene glycol and deionized water at a volume ratio of 4:6, started the device, and started refrigeration and circulation.

Fortunately, the machine is not broken, the temperature reading on the digital display panel is starting to drop from more than 20, and the coolant in the pipeline can also be seen to be circulating with the naked eye.

After fixing the circulating cooling device, Xu Qiu began to check the water pump.

The water in the pump is pretty clean and doesn't need to be treated. Maybe Duan Yun has used it recently.

...

Half an hour later, the Soxhlet extraction was completed, and the liquid in the extraction tube was basically colorless.

Xu Qiu shut down the device, and after the solution cooled down, transferred the solution in the Erlenmeyer flask to an eggplant-shaped bottle in a fume hood.

Start the rotary steaming.

When about 15 milliliters of chloroform solvent remained in the eggplant-shaped bottle, the rotary evaporation was stopped.

Then plug the mouth of the bottle with a rubber stopper, put the eggplant-shaped bottle on the rubber bottle holder, and set it aside.

He used the same treatment method to treat the other three bottles of solution to the remaining 15 ml of solution.

Then, the chloroform solution was dropped into methanol to precipitate a solid polymer product, which was filtered.

Wrap the product with filter paper and put it in a vacuum oven.

Finally, Xu Qiu recycled the chloroform obtained by rotary evaporation, put them back into the original bottle, and marked a big back on the bottle label with a marker pen, indicating that it was recycled chloroform.

Theoretically, the purity of chloroform collected after rotary evaporation is relatively high.

It is the product of distillation and is as pure as distilled water if the collection bottle is clean enough.

The main reason is that Xu Qiu used nearly one liter of chloroform solvent in total, and it would be too wasteful to treat it all as waste liquid.

Chen Wanqing watched the whole process, but she couldn't help much because there was only one rotary steamer.

Junior has worked hard, let me handle the next batch of products. Chen Wanqing said.

Okay. Xu Qiu glanced at the time, it was after four o'clock in the afternoon, and then asked:

It's past four o'clock, are you still submitting a response today?

Vote, everyone is here, just take the later school bus back at night, the last school bus is 9:30. Chen Wanqing said.

Then I will make a PBT4T today, and then make a P2FBT4T, that is, add two fluorine atoms to the BT unit, and keep other conditions unchanged for the time being. Xu Qiu said.

I'm going to make three today, and adjust the molar ratio of A units in the ternary polymer, 1:1, 3:7 and 7:3. Chen Wanqing said:

From this point of view, today's task is quite difficult.

Yeah, come on. Xu Qiu said.

Take a short break and continue the experiment.

Re-distill toluene, set up a reaction device, and make nitrogen balloons.

Fortunately, Xu Qiu came prepared this time. For the new material P2FBT4T, he had already obtained the relative molecular mass of the monomer in the Chemdraw software in advance, and calculated the mass of the feed.

Now the reaction conditions are still being explored, so this time it is still a small amount of feed, the total of the two monomers is less than 200 mg.

During the experiment, there was a little accident.

After re-distilling toluene for an hour, the indicator did not turn blue.

Xu Qiu deduced that the reason for the rapid blue color the previous two times was that the toluene solvent had just been unsealed and had an extremely low water content.

This time, it should be because the toluene has been placed in the air for a long time and has absorbed a small amount of water.

In theory, more reflow for a while will do.

It happened that the time was close to the meal time, so the two decided to let the toluene continue to re-steam and go to eat first.

...

After dinner, return to the laboratory.

The indicator in toluene has turned blue.

The experiment continued, and there were no surprises after that.

After fighting for three hours, the two voted for all five responses.

Xu Qiu not only voted for two of his responses, but also completed one for the senior sister.

It's nine o'clock in the evening.

Xu Qiu took out four polymer products from the vacuum oven, weighed them, bottled them, and marked them.

While operating, he said:

Sister, how long do you think we should take to respond to this batch of responses?

Let me think about it, Chen Wanqing thought for a moment, then said:

We voted for responses at about 8 o'clock in the evening. If we set a 12-hour response time, we would have to come back at 8 o'clock tomorrow morning to close the responses.

Let's set it at 18 hours, so that we will close the response at 2 o'clock in the afternoon, and the time will not be so rushed.

In the simulated laboratory, Xu Qiu submitted three reactions. It took only 12 hours for the reaction time, and a large amount of polymer had already been precipitated.

Thinking of this, he made a decision:

Well, I'm staying here today, and I'll wake up around eight tomorrow morning to see how the reaction is going.

If a large amount of polymer has been precipitated, stop the polymerization and start the capping reaction;

If there is no product precipitation yet, how about waiting for you to come over?

Okay, you have to pay attention to safety when doing experiments here alone, Chen Wanqing hesitated:

Or I... Forget it, then I'll go first, or I won't be able to catch the school bus.

After all, she put her schoolbag on her back and flew away like a gust of wind.

Xu Qiu looked at her back, and then at the time, it was only ten past nine.

This side is at most five minutes away from the school bus stop, what is the senior doing in such a hurry, she even forgot to take the processed samples.

Xu Qiu shook his head and entered the A502 laboratory to do the finishing work.

First, put the processed four batches of samples into a vacuum tank containing monomers for safekeeping.

Then slowly pour the toluene with sodium into absolute ethanol, and after the sodium reaction is complete, pour it into the waste liquid bucket as waste liquid.

Sodium metal can react mildly with ethanol, so ethanol is generally used to treat waste sodium.

It is better to use new toluene next time, otherwise the longer the toluene is left outside, the re-steaming time will only become longer and longer.

Next, soak the newly produced dirty bottle in the alkali tank.

Finally, tidy up the laboratory and turn off the water, electricity and gas in the laboratory.