The Fiery Era: Starting from Longxugou

"Brother, what do you want to try? I'll help you!"

While enjoying the delicious meat, upon hearing her elder brother's words, Zhao Xiaoyue immediately declared that her brother would definitely make money from writing new articles, and then they would have meat to eat again.

"Big brother, I'll help you too! I'm really strong!"

As Zhao Shijie spoke, he rolled up his sleeves to show off his skills.

"Okay, you two come and help! Haha!"

Zhao Shi'an laughed when he heard this. To purify crude salt, the salt needs to be dissolved first. With his younger siblings helping, he wouldn't have to do it himself.

"Boss, what article are you writing? Are those two capable of doing the work? Can I help you?"

After hearing this, Liu Guiying worried that her youngest daughter and son wouldn't be able to do the job well, so she offered to help.

"Mom, you're quite capable! It's just stirring the water in the basin with a stick, it's no trouble at all!"

"Okay, you decide what to do!"

Upon hearing this, Liu Guiying didn't press the matter further, assuming that her eldest son was just fooling the two little ones.

After having lunch, Zhao Shi'an rested for a while and then went directly to school.

The next day, Sunday, after breakfast, Zhao Shi'an took his younger siblings to the general store at the entrance of the alley. They bought a large earthenware basin, two small earthenware jars with lids, two feet of coarse gauze, half a pound of lime, and two ounces of alkali powder. He originally wanted to buy caustic soda, but the general store didn't sell it. If he wanted to buy it, he would have to go to the state-run chemical store, so he bought lime instead.

Back home, my mother and aunt sat in the yard making shoes in the sun, while Uncle Tian's family went to the flower market to sell winnowing baskets and willow baskets. Sunday was a busy day, so it was a good time to sell.

"You're back? Hey, Shi'an, what are you doing buying a pot? We already have one at home! You also bought a jar and a cloth! What are you doing?"

Sun Cuilan looked at the things the people were holding with great curiosity.

"Boss, why are you buying so much?"

Liu Guiying was quite surprised to see the things in her eldest son's hands. These things added up to at least 20,000 yuan. Wasn't it supposed to be for writing an article? Why is it costing money?

"Mom, Auntie, this is for my experiments! This basin and jar are useful. Oh, and you two can divide this two feet of cloth as cage cloth. Give me the cage cloth from home, I need it!"

Zhao Shi'an explained that he asked his mother and aunt for the family's steamer cloth, which had been used for several years and was so black that it was unrecognizable.

He bought two feet of coarse gauze to replace the old broom cloth at home, which could be folded up and used as filter paper to filter out impurities such as mud and sediment from the coarse salt.

"Shi'an, what do you need the cage cloth for?"

"Yeah! Aren't you a writer? Why did you buy all this stuff?"

Sun Cuilan and Liu Guiying were puzzled when they heard this.

"Mom, Auntie, I'm doing an experiment. Our salt is all in large blocks, and I'm going to purify it so it won't be bitter. That way, it'll taste better when stir-frying vegetables or making salty soup..."

"What's purification? Shih-an, you think you can make a large lump of salt not bitter with these things?"

Although Sun Cuilan didn't understand, she knew that salt that wasn't bitter was valuable.

"Yes!"

Zhao Shi'an nodded.

"Our Shi'an is really capable! You wait here, Auntie will go get it for you right away!"

Upon hearing this, Sun Cuilan got up without saying a word and went home to get the cage cloth.

"Boss, the cage cloth is hanging on the wall, you can get it yourself!"

"Mother, I understand!"

As Zhao Shi'an spoke, he instructed his two younger brothers to first wash the earthenware basin clean and fill it with water, then weigh out ten catties of coarse salt. After that, he wrapped the large salt block in a cloth, smashed it with a hammer, and put it into the large basin filled with water. Then he instructed his younger brothers to stir it carefully and slowly dissolve the salt!

The earthenware basin is about 30 centimeters in diameter and about 15 centimeters in height. When filled with water, it can hold about 12 liters, or 24 jin (approximately 12 catties).

At room temperature, 100 jin of water can dissolve 36 jin of salt, and 24 jin of water can completely dissolve 8.64 jin of salt. If you put in 10 jin of coarse salt, even if the refined sodium chloride in the coarse salt is only 90%, there will still be a lot of salt and mud and sand impurities left.

The impurities filtered out can replenish the poultry's salt, so it's not a waste!

"Stir slowly, be careful not to splash water!"

"Understood, big brother!"

After hearing this, Zhao Shijie and Zhao Shixiong became much more careful in their actions.

"Boss, does this really work?"

Liu Guiying was a little worried when she saw her eldest son put ten catties of salt directly into the basin.

"It works! Mom, this is similar to using vinegar to remove the alkalinity before! Don't worry! Even if it doesn't work, the salt won't decrease after the water dries up!"

Seeing his mother's reaction, Zhao Shi'an offered words of comfort.

"Sister-in-law! Shi'an will definitely get it done, just wait and see!"

Sun Cuilan held her sister-in-law's hand and comforted her, having full confidence in her nephew!

"I know, I'm just worried he'll cause trouble!"

Liu Guiying explained that while making shoes, she would occasionally watch the other people's movements.

After stirring for a while, Zhao Shijie and Zhao Shixiong felt a bit tired. Zhao Xiaoyue and Zhao Xiaole volunteered to take over for their two brothers. The two little girls were even more exhausted after a short while. Zhao Shi'an took the wooden stick and stirred it. At the same time, he used his mind to check and found that sediment was slowly accumulating at the bottom of the basin.

After stirring for about ten minutes, the salt was almost dissolved.

Zhao Shi'an told his younger siblings to stop, and then began to prepare lime.

When lime dissolves in water, it generates heat, which raises the water temperature. The increased water temperature, in turn, increases the solubility of salt, allowing more salt to dissolve.

However, he bought too little lime, so the water temperature didn't rise much.

The main purpose of using lime is to remove magnesium ions from the water.

When lime comes into contact with water, it produces calcium hydroxide. Hydroxide ions combine with magnesium ions to form a precipitate, thus achieving the purpose of removing magnesium ions.

While caustic soda could also achieve the same result, its high price and scarcity made lime the preferred alternative for removing magnesium ions.

After removing magnesium ions, adding some alkali to the salt water will remove calcium ions.

The main component of alkaline surfaces is sodium carbonate, and carbonate and calcium ions will form precipitates.

This process purifies the crude salt. As for the sulfate ions inside, they have no effect and do not need to be removed.

After all, modern industry doesn't specifically remove sulfate ions; it's not only costly but also troublesome. Although barium chloride can remove them, it's highly toxic and prone to causing problems, so it's not specifically used to remove sulfate ions.

With these thoughts in mind, I had a clear idea of ​​how to purify crude salt. From a cost-saving perspective, crude salt can also be purified using only alkali.

When alkali is added to salt water, carbonate ions will first react with calcium ions to form a precipitate. Excess carbonate ions will combine with magnesium ions to form a substance that is slightly soluble in water. Although it does not reach the level of magnesium hydroxide precipitation, it can remove most of the magnesium ions.

The human body cannot perceive bitterness as long as the concentration of magnesium ions is below 10 to the power of negative three, and this can be achieved using only alkaline powder.

After waiting for a while, seeing that the water in the basin had become much clearer, Zhao Shi'an said to the group:

"Everyone, move away, be careful not to get burned!"

Upon hearing their elder brother's words, Zhao Shijie and Zhao Shixiong quickly pulled their younger sister away to keep their distance.

After his younger siblings had gone far away, Zhao Shi'an added lime to the basin.

He calculated based on a magnesium ion content of 0.5%. Ten catties of coarse salt contains about 25 grams of magnesium ions. On a 16-ounce scale, one ounce is 31.25 grams. Considering that lime is not pure, he estimated it based on a purity of 80%. Through chemical equation calculation, he concluded that about three ounces of lime would be needed.

When lime is poured in, white smoke hisses and bubbles constantly rise from the surface of the water, and the liquid splashes everywhere. White flocculent precipitates gradually appear in the solution.

Zhao Shi'an used his mind to create a protective shield in front of him and continued to stir with a wooden stick to prevent the lime from settling and clumping, thus ensuring that the magnesium ions were completely removed!