The synthesis method of cryolite, what compound is cryolite

There are mainly the following processes for the production of cryolite at home and abroad:

Hydrofluoric acid. Method: can be divided into dry and wet dry method is to combine gaseous hydrofluoric acid in 400 700 and aluminum hydroxide.

reaction, fluoroaluminic acid (H3ALF6) is generated, and then soda ash is used.

It is formed by reacting at high temperatures. The wet process is prepared by reacting 40 60% hydrofluoric acid with aluminum hydroxide and then adding soda ash.

Fluorosilicic acid method: ammonium fluoride intermediate product and sodium fluorosilicate intermediate product method can be separated, the former is fluorosilicic acid and ammonia.

After ammoniation, it is formed by reacting with sodium aluminate. The latter is prepared by passing the fluorine-containing waste gas in the production of phosphate fertilizer through sodium fluorosilicate, and then through ammonia synthesis and other processes.

Carbonation method: carbon dioxide is used in sodium aluminate and sodium fluoride solutions.

Cryolite can also be made.

Aluminum industry method: from the waste gas of aluminum smelting production, the reaction of dilute hydrofluoric acid with sodium aluminate can be cryolite.

Alkali method: soda ash, fluorstone, silica sand by roasting, crushing, leaching and then reacting with aluminum sulfate, which is rarely used in industry. Ignition reduction is an important test index of cryolite, and it is an example of the percentage of ignition loss in the environment of cryolite material 550.

The ignition reduction of cryolite was a new indicator when the national standard was formulated in 1999, and the national standard in 1984 did not have this item. With the progress of society and the development of aluminum electrolysis industry, the automation level of industrial production and environmental protection have been paid attention to, and it is urgent to improve the performance of cryolite, which is the raw material for aluminum electrolysis. The level of cryolite ignition directly affects its use effect in aluminum electrolysis production, and the high ignition reduction will cause cryolite hydrolysis, flying, low material utilization, aggravated environmental pollution and other problems, and the lower the ignition reduction, the better the use effect.

Therefore, reducing ignition is the primary problem to be solved to improve the quality of cryolite products and produce high-quality cryolite.

Cryolite is a mineral. Monoclinic system. Columnar crystals or blocks. Mohs hardness. Density to g cm. Refractive index.

Birefringence, positive light. Dispersion value.

Glass gloss to grease sheen. Transparent. Colorless, white, brown, or red.

Occurs in granite and pegmatite intruding gneiss. It is used in the refining of aluminum. Hydrofluoric acid, sodium carbonate can be used.

and aluminum to make synthetic cryolite. The main production area is Greenland.

The protrusions are lower, the interference color is very weak, and the pseudo-cube cleavage can be distinguished from fluorite. It is completely decomposed in concentrated sulfuric acid.

Hydrofluoric acid method. Fluorosilicic acid method.

Carbonation. Aluminium industry ** law.

At present, most of the ice crystals are liquid, and they need to be frozen in the freezer compartment of the refrigerator for more than 6 hours before use, and then put them in the air conditioner fan water tank for normal use. If you want to cool for too long, you can prepare several ice crystal cassettes to alternate, and use two or more ice crystal cassettes at the same time to make the cooling effect better.

Ice crystals are usually placed in the tank of the air conditioning fan, and there are two types of ice crystals, one is gelatinous ice crystals and the other is powdery ice crystals with no flushing in them. In both states, the ice crystals are packed in containers made of high-strength, low-temperature resistant materials, and it is necessary to check which type of ice crystals they are before using them.

In order to achieve a better refrigeration effect, it is necessary to freeze the ice crystals in the freezer room of the refrigerator for more than 6 hours in advance, and put them directly into the water tank of the air conditioning fan after freezing, and they can be used normally.

If you want to let the air conditioner fan cool for a long time, it is recommended to prepare a few more ice crystal boxes, and then use the ice crystal boxes alternately after the round. If you want the air conditioning fan to cool down better, you can use two or ice crystal boxes at the same time.

1. Cryolite (cryolite) is a mineral, sodium hexafluoroaluminate (Na3ALF6), white monoclinic crystal system (1009 degrees Celsius), slightly soluble in water, molten cryolite can dissolve alumina, rotten hunger in the electrolytic aluminum industry as a flux, the manufacture of milky white glass and enamel sunscreen.

2. Minerals refer to the elemental elements and their compounds that are produced and developed in various geological processes and are relatively stable under certain geological and physicochemical conditions. Minerals have a relatively fixed chemical composition, and those that are solid also have a definite internal structure; It is the basic unit that makes up rocks and ores.

1) In the early process of fighting monsters, the system will send some ice crystal fragments to the player, and those who don't have enough backpacks should not sell them.

2) After Figure 11, a Rough Ice Crystal will be dropped. Coupled with the Ice Crystal Primordial Fragments given by the previous system, it is enough to upgrade the Frost Demon Dragon to the full level. It is more difficult to pass Figure 11, and the specific recommended team configuration is:

Snowman + Nightblade Squire + Vampire + Judgment + Mercenary, plus a wet nurse. For details, please click: Underground Castle Figure 11 Raiders.

Werewolf + Vampire + Nightblade + 2 nurses, the rest can be freely chosen, nurses are indispensable. If you don't have a legendary talent at this time, it is recommended to put two vampires. But generally speaking, by the time of Figure 12, you should buy the legendary talent.

If you don't buy it, it's too early, and you need this talent to play later.

How to use the ice crystal box of the air conditioner fan: Put the ice crystal box into the freezer compartment of the refrigerator and freeze for more than 6 hours. Place the frozen ice crystal box into the water tank after the air conditioning fan is filled with water, and the water volume should not exceed the ice crystal box.

The optimal configuration is a 1:1 ratio of water to the volume of the ice crystal cassette.

Due to the cost, there are generally only 1-2 ice crystal boxes included with the host, and they are small, and the ice crystal box can be purchased to reduce the water temperature and prolong the low temperature time. When using ice crystals, you need to put them in the air conditioner fan tank, but it should be noted that you need to add water to the water tank, be sure to not pass the ice crystals, and keep the amount of water filled equal to the volume of ice crystals.

Generally speaking, the effective use time of an air conditioner fan ice crystal box after six hours of freezing is 2-3 hours, and then there is no effect, and the air conditioner fan ice crystal box needs to be replaced. If you use an air conditioning fan, it is best to prepare a few more ice crystal boxes for the air conditioning fan, which can be used interchangeably. Generally, the service life of each air conditioner fan ice crystal box is 3-5 years, because the filling inside will volatilize with use.

When winter comes, there is no need to turn on the refrigeration function of the air conditioner, so the ice crystals will be suspended, at this time, we must pay attention to the storage of ice crystals, which are greatly affected by temperature, and if they are not kept at a constant temperature, the service life of ice crystals will be greatly shortened.

Air conditioner fan ice crystal features

The shell of the ice crystal box is generally made of high-strength and low-temperature resistant materials, and the inside is equipped with cold storage liquid, which can generally be used in circulation. The freezing point of the cold storage liquid is minus 12, that is, the cold storage liquid in the ice crystal box can form ice at minus 12 degrees, and its freezing point is lower than that of water.

Therefore, the cold energy stored and the cold released when dissolved are much greater than that of water, which can quickly cool down and relieve heat in the hot summer. It has the characteristics of sufficient cold storage, fast cooling, and slow cold release.

The ice crystals of the air conditioner fan are sealed with rubber stoppers and aluminum covers, which will not cause leakage, and have the characteristics of non-toxic, in line with health standards, and large cold storage capacity. Nowadays, ice crystals are widely used in air conditioning fans for cooling and refrigeration. Before using the air conditioning fan, it is generally necessary to put the ice crystals in the refrigerator for 5 to 6 hours to freeze, and then put them into the air conditioning fan water tank to cool down, recycle, and never expire.

1. At present, most of the ice or crystal digging is liquid, which needs to be frozen in the refrigerator freezer for more than 6 hours before use, and then put it into the air conditioner fan water tank for normal use. If you want to refrigerate for too long, you can prepare several ice crystal boxes to alternate, and use two or more ice crystal boxes at the same time to make the cooling effect better.

2. Ice crystals are solid hydrates formed by water vapor condensing on the ice core and increasing its height. Ice crystals are an essential medium for the formation of snowflakes, which are centered on some dust and together with water vapor to form an ice-like substance at lower temperatures, and as the ice crystals grow, the water vapor near the ice crystals is consumed. Therefore, the closer you are to the ice crystals, the thinner the water vapor and the lower the degree of supersaturation.

In this way, ice flakes will form, and when they fall to the ground, they will become snowflakes. In addition, ice crystals can also refer to the cold storage fluid used in refrigeration equipment, such as ice crystal ice pads.