This experiment is not only of great practical significance, but also an excellent educational opportunity, so in addition to the participants Agatha, Sylvie, Chames and Kaimer Strell, Roland put other members of the Witch League, Carter, Iron Axe, and Barov also called over. In order to accommodate the twenty or so people, the test site was selected in the fifth laboratory with the largest space.
For the first attempt, the fractionation vessel was not made too large, about one person tall and one meter in diameter, similar to a tower. The interior of the container is divided into three layers, the bottom layer is used for air intake, and the upper two layers are used for exhaust air.
Before the separation began, Roland gave everyone a simple chemistry class, told them what might happen, and asked a few small questions by the way, so that everyone could find the answer by themselves. In addition to arousing the interest of the listeners, it also Greatly enhance the effect of teaching, which is also a technique used by chemistry teachers.
"…Theoretically, when Agatha lowers the internal temperature of the container, the air will gradually condense into liquid, pass through the perforated partition, and drip to the bottom. So when you observe liquid accumulation at the bottom, let us know."
Since he couldn't see it directly, he had to rely on Sylvie to observe the changes through the container and describe the changes, so Roland went into particular detail in this part.
Sylvie nodded suspiciously, "Can you really see the liquid appearing? Could it be the water vapor in the jar?"
"Don't worry, the liquid air is light blue, completely different from water vapor." Roland waved his hand, "And at that temperature, the water vapor would have already solidified into ice crystals." Then he made a gesture to Agatha, "Then let's start."
"Wait... Doesn't this hole in the bottom of the container need to be plugged?" she asked.
"It will be blocked again later, otherwise there will be too little air in the tank, and no obvious changes will be observed." Since it was just an experiment, Roland chose the easiest way to inhale. When the temperature in the tank drops rapidly, the pressure will follow It is lowered, so that the outside air keeps pouring into the tank. This is not worth the gain in conventional production, because the air-conditioning will continue to lose energy and waste energy, but Agatha uses magic power, and the cooling efficiency is much higher than that of any refrigerator, so Roland is too lazy to prepare the air pump to inflate.
Agatha took a deep breath and put her hands on the fractionation tower.
After a few breaths, a whistling sound appeared in the intake duct, which was the sound of the rapid influx of air. Layers of hoarfrost appeared around the mouth of the nozzle at a speed visible to the naked eye, and the moisture in the air continued to expand. Ana turned the black fire into silk threads, cleaning up the thickening ice crystals.
After a while, Sylvie said in surprise, "I saw liquid on the partition, but it was more white frost."
"The white frost could be influx of water vapor, or it could be crystallized carbon dioxide," Roland explained. "Considering that the carbon dioxide content in the air is extremely low, most of it should be water vapor."
In the formal production, the air must be dried before being pumped into the fractionation tower. Otherwise, the condensed water vapor will easily block the stratified plate and the exhaust hole, which will reduce the production efficiency.
About half an hour later, Sylvie reported that the bottom of the container was filled with blue liquid, and Roland asked Soraya to block the intake pipe and seal it with a coating.
Next comes the crucial warming.
According to the different melting and boiling points of nitrogen and oxygen, nitrogen will first reach the boiling point and turn into a gas to escape upwards, thereby realizing separation. He didn't remember the specific value of this temperature, and there was currently no means to measure it, so he could only rely on Agatha to grasp it. The specific performance is that gas is discharged from the exhaust hole at the top of the fractionation tower, and the remaining liquid at the bottom will become more and more blue, which means that the purity of liquid oxygen is constantly improving.
Fortunately, Agatha was no stranger to the control of magic power. She precisely adjusted the cooling rate and made it slowly rise. After a while, Sylvie also observed the boiling phenomenon of the liquid surface. Bubbles began to bubble up in the coating tube running into the water, and Kemo quickly collected several bottles of gas using the drain gas collection method.
"Is this nitrogen?" Lily pouted, "I can't see anything at all."
"That's the first question I asked before," Roland asked. "How to prove it's different from air?"
"Ignite," Tilly answered first. "In Elementary Chemistry, it is said that combustion requires oxygen. If it is another gas, it should instantly extinguish the burning wood block."
"You'll know if you re-cool it into a liquid," Agatha said after thinking for a moment, "Didn't you say that nitrogen is colorless after liquefaction?"
"Or to export the remaining liquid in the container to prove that the latter is pure oxygen can also prove the diversity of air components." Anna said.
The scene has completely become a stage for Xueba to perform. Test methods are proposed one by one, and then discussed with each other. There are only a few voices left in the laboratory. Roland looked around and found that Nightingale, Andrea, Maisie and other witches, as well as the head of the city hall and the chief knight Carter, all looked at a loss. The Iron Axe, the commander of the First Army, maintained an expression at all times. Probably no matter what he said, he would nod his head in yes.
Well, Roland sighed in his heart, it seems that this chemistry class is a little out of line.
If there are still people who can feel the joy of His Royal Highness, I am afraid that only Kemer Strell and Chamis are left.
"Your Highness, this is really... miraculous," the young alchemist exclaimed. "You have proved the correctness of Elementary Chemistry. I'm afraid all alchemists would not have expected that even the air that can be seen everywhere is so complicated."
"With pure oxygen, is it possible to observe a more violent oxidation reaction? I have a lot of experiments I want to do," Kemo said excitedly.
Roland nodded, but another thought suddenly popped into his mind.
Nitrogen is the main raw material for artificial synthesis of ammonia. It can be reacted with hydrogen under the condition of high temperature and high pressure plus catalyst to obtain ammonia gas. The latter can not only be used to make nitrogen fertilizer, but also can be used to synthesize nitrogen oxides to obtain nitric acid. But to achieve this process, there is still a lot of work that needs to be done, such as air pumps, vacuum gas storage tanks and a series of complex reaction equipment. Even if white paper can provide the function of a catalyst, it will take trial and error.
Now, since he has pure oxygen and pure nitrogen, why not directly produce nitric oxide
It is true that the chemical industry chooses to use ammonia gas to produce nitric acid because the reaction of oxygen and nitrogen is an energy-absorbing reaction, which cannot be carried out spontaneously and requires external energy supply. where the soil is more fertile. Because of this, this method has high equipment requirements and high energy consumption, so it is not suitable for formal production.
But if there is an urgent need to increase the production capacity, this production method is the most efficient, and does not even need a catalyst, just a continuous discharge... or other means to achieve the high temperature generated by the arc.
Roland naturally thought of Black Fire.
The heating efficiency of black fire is not worse than that of electric arc, and the burden on Anna is extremely low. As long as the nitrogen and oxygen are purified and mixed in proportion and poured into a closed reactor, nitrogen monoxide can be continuously generated.
He decided to try this method.
(.)
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