King of German Mercenaries

With disappointment, Marin left Cologne with the team and returned to Texel. Along the way, the little girl Angela saw that Marin was not happy and couldn't help comforting him. He even sang and danced to relieve Marin's boredom, which made Marin feel a lot better.

When he returned to Den Burg, Marin found that the spring ploughing on the five large islands was in full swing. Of course, what unfolds is the first step - cultivating the land...

Marin owns most of the horses—except for the warhorses and pregnant mares, all of whom are pulled down to the fields. In addition to these draught horses, the island also bought a lot of cattle, put on nose rings, and also pulled down the fields to cultivate the land.

After ploughing the land, it is fertilizing. In fact, that is, the manure that has been extracted from the septic tank is mixed with plant ash, fish bones, fish scraps and dead fish, etc., and then sprinkled into the fields. Then, in a few days, the seeds can be planted.

In fact, after the manure is extracted from nitrate, the nitrogen content is reduced, which affects fertility. However, this is not a problem, because as long as more application points are applied, the problem of the decline in nitrogen content can also be compensated.

Now that the population is so large on the island, many horses have been raised and sheep have been raised on a large scale. Therefore, there is no shortage of feces on the island. And because of the large scale of fishing in the Wadden Islands, there is no shortage of fish bones, scraps and dead fish. Therefore, it can be said that there is no shortage of nitrogen fertilizers and phosphate fertilizers in the three major fertilizers.

However, the potassium fertilizers in the three major fertilizers are somewhat insufficient. Because there are few plants and trees on the archipelago, and there is not a lot of plant ash. Also, plant ash is a bit low in potassium. Although it is said that the potassium salt in plant ash is potassium carbonate, it is the best potash fertilizer, stronger than chloride-chloride-potassium or something. Under the same potassium content, the fertilizer effect of plant ash is stronger than that of special potassium fertilizer.

However, the amount of grass ash in the Wadden Islands is limited. The plant ash mainly comes from residents making fires for cooking. Komarin promoted coal burning on the island, which reduced the production of plant ash a lot. In addition, there are few plants and trees on the archipelago, and it is not enough to burn. So, Marin feels that there is a bit of a lack of potash right now...

Coincidentally, at this time, good news came from Kohler...

It turned out that Marin had asked Kohler to send people to the Harz Mountains to buy bitter salt mines. So Kohler followed Marin's instructions and hired Jewish merchants to go to the Harz Mountains to find bitter salt mines...

After a long period of inquiries, the Jewish merchants hired by Kohler's men finally found the bitter salt mine. However, when the bitter salt sample was sent back for the first time, Marin was tested for flame reaction and found that it was not potassium salt. (Potassium salt flame reaction is purple)

Then, after a simple experiment, Marin discovered that the bitter salt was Glauber's salt (a hydrate of sodium sulfate) at all, not the potassium sulfate he needed.

So Kohler once again sent people to look for other bitter salt mines...

While Marin was worried about not enough ash, a new batch of bitter salt samples came back. After the flame reaction test, Marin found that it was potassium salt...

However, this potassium salt seems to have a lot of impurities. Because, when the potassium salt reacts with the flame, the lavender cannot be seen clearly, and it is greatly disturbed by the yellow color of the sodium element. Fortunately, the last time Marin brought back a lot of stained glass from Venice, there was blue cobalt glass specially designed to filter yellow. Through the cobalt glass, Marin saw the long-awaited purple flame...

Marin can now confirm that this bitter salt contains a lot of potassium, but it is also doped with a lot of sodium. Because it is bitter salt, there must be a lot of sulfate ions in it. However, Marin suspects that it may also contain a lot of chloride ions...

Marin just wanted to use the bitter salt as potash. So, both sodium ions and chloride ions are unnecessary things. Therefore, he began to think of a way to separate the sodium and chloride ions as much as possible to increase the potassium content.

Therefore, Marin found a few large pots and a few workers who boiled salt, and began to use the principle of different solubility of salt to separate sodium and chloride ions...

The solubility of sodium chloride is relatively stable.

The change with temperature is small. The solubility of potassium salts varies greatly with temperature. Marin used this principle to start simple separation.

First, Marin took out the salt and prepared a saturated salt water. Then, he asked the workers to heat the cauldron with saturated salt water.

When the saturated brine boils, Marin starts adding bitter salt...  

As soon as the bitter salt was added, a lot of crystals were precipitated. Marin can conclude that these are sodium chloride - since sodium chloride is saturated in this solution...

Marin had the workers filter out the crystals that precipitated out in the first place, the excess sodium chloride. Then, assuming that it was nearly saturated, Marin stopped adding the bitter salt and filtered off the excess sodium chloride crystals.

Next, Marin removed the flame and let the brine cool down to room temperature. At this time, a lot of salt precipitated out of the pot...

Marin knew that the precipitated salt was probably a mixture of potassium sulfate and sodium sulfate. However, Marin had no way of separating the sodium sulfate. If you change to a mixture of ****** and sodium chloride, it will be easy to separate. The solubility of potassium sulfate and sodium sulfate are too similar to separate them.

Moreover, even if potassium sulfate is mixed with sodium ions, it does not matter. Anyway, this is only used as agricultural fertilizer, not for chemical experiments, not so strict.

After purification, Marin carried out the flame reaction again. After observation, Marin found that the yellow flame was dimmed a lot, and the purple flame was more obvious. Therefore, Marin can conclude that the potassium ion content is now much higher and can be used as a higher potassium fertilizer than grass ash.

Coincidentally, this time Kohler's men brought back a lot of bitter salt, about a dozen tons. Marin simply used this method to separate. Then, a dozen or so tons of bitter salt were extracted out of a mixture of about seven or eight tons of potassium sulfate and sodium sulfate.

Marlin sent people to pack all of this mixture in sacks. After that, he arranged for another group of unsuspecting people to take advantage of the night to pour the mixture of seven or eight tons of potassium sulfate and sodium sulfate into each septic tank... Except for a few people, no one else knew about it. ...

But Marin knew that this time, because of the addition of phosphorus-containing fish scraps and potassium-containing bitter salt and plant ash, when the autumn harvest, because the three major fertilizers were complete, the production of rye would definitely increase...

I dare not say that the yield per mu is as high as 1,000 catties like the later generations, but it can still be achieved with a yield of 400 to 500 catties per mu. This is mainly because the fertilizer efficiency of these soil and fertilizer mixtures is not as good as that of purified fertilizers. Also, the seed varieties of this era are really bad. Therefore, it is not bad to have a yield of four or five hundred catties per mu. This is also because Marin popularized the method of salt water immersion selection, and chose excellent seeds for sowing.

Although a lot of potassium fertilizer was added this time, Marin was also very dissatisfied. Because, he has no way to separate potassium sulfate and sodium sulfate.

Therefore, Marin ordered Kohler to send someone to find non-bitter mineral salts (without sulfate ions) and bring them back for him to use the flame reaction method to check. If there is a purple flame, it contains chloride-potassium chloride. And since salt is not bitter, there must be no sulfate ions. Using the method of solubility, it is very simple to separate sodium chloride and sodium chloride, and the purity is high...

Of course, this is another story. Now, Marin also has a potash mine with low purity. Marin still ordered people to buy this bitter salt mine and use it as potash fertilizer.

Because the bitter salt mine is hesitant to use, and the price is not high. The non-bitter potash mineral that does not contain sulfate ions, because chloride-potassium can actually replace sodium chloride as table salt. Therefore, the cost of buying such a salt mine is too high, and it is not cost-effective. It is better to use this bitter salt mine first. But Marin heard that the price of this bitter salt mine is basically the price of cabbage. Before, there were only some black-hearted profiteers who used these useless bitter salts as table salt and sold them to consumers. Other than that, there is no other use for this bitter salt. Even if black-hearted merchants use it to pretend to be salt, the sales are not good. Because consumers are deceived once, it is impossible to buy this bitter salt next time. Therefore, this bitter salt mine is useless, so the selling price is very low. Marin can win it for very little money, so why not do it?

UU Reading Books welcomes all book lovers to come and read, the latest, fastest and most popular serial works are all in UU Reading Books! Mobile users, please read.