What is Sodium hydrofluoride used for?

The reaction between sodium (Sodium) and hydrofluoride (hydrofluoride) was unknown in the era of Tiangong Kaiwu. However, with today's chemical knowledge, the role of the two is quite important.

Sodium, an active metal, reacts violently in contact with water, while hydrofluoric acid, a corrosive weak acid. When sodium meets hydrofluoric acid, sodium reacts with water in the hydrofluoric acid solution first, with the formula:\ (2Na + 2H_ {2} O = 2NaOH + H_ {2}\ uparrow\). The resulting sodium hydroxide (\ (NaOH\)) interacts with hydrofluoric acid to form sodium fluoride (\ (NaF\)) and water, with the formula:\ (NaOH + HF = NaF + H_ {2} O\).

In industry, sodium fluoride is widely used. It can be used as a wood preservative and wood protection to resist moths and decay. In the metallurgical industry, it can melt ore to reduce its melting point and promote the refining of metals. And in agriculture, it can be used as an insecticide to remove pests to protect crops. In the chemical industry, it is a raw material for the production of other fluorine-containing compounds.

Although the reactions and uses of the two are not contained in "Tiangong Kaiwu", today's chemical development has made significant contributions to the role of sodium and hydrofluoric acid in various fields, bringing many conveniences and progress to human production and life.

What are the physical and chemical properties of Sodium hydrofluoride

Sodium (Sodium) reacts with hydrofluoride, both of which have unique physical and chemical properties.

Sodium, soft and silver-white, has extremely active chemical properties. In the air, it interacts with oxygen instantaneously to produce sodium oxide; in contact with water, it reacts dramatically, releases hydrogen and forms a sodium hydroxide solution. The reaction formula is: $2Na + 2H_ {2} O = 2NaOH + H_ {2}\ uparrow $. This reaction is rapid and produces a lot of heat, causing hydrogen gas to explode.

Hydrofluoric acid, aqueous solution of hydrogen fluoride, is highly corrosive and weakly acidic. Although the acidity is weaker than many strong acids, it has a unique corrosive power to glass and silicon-containing materials. Because it can react with silicon dioxide, the reaction formula is: $SiO_ {2} + 4HF = SiF_ {4}\ uparrow + 2H_ {2} O $, so it is commonly used in plastic containers.

When sodium meets hydrofluoric acid, sodium first reacts violently with water (hydrofluoric acid contains water), just like the above reaction with water. At the same time, hydrogen ions in hydrofluoric acid also react with sodium, accelerating sodium consumption. The generated sodium hydroxide reacts with hydrogen fluoride in hydrofluoric acid to form sodium fluoride and water. The reaction formula is: $NaOH + HF = NaF + H_ {2} O $. This series of reactions generates heat, or volatilizes hydrogen fluoride, increasing the concentration of hydrogen fluoride in the air, its toxicity, inhalation and contact are dangerous to human health.

In short, the reaction between sodium and hydrofluoric acid is complex, involving multiple steps, and because sodium is active and hydrofluoric acid is highly toxic, the operation must be cautious and follow strict safety procedures.

What is the production method of Sodium hydrofluoride?

Sodium reacts with hydrofluoric acid in the following ways:
Sodium, a metal that is active; Hydrofluoric acid, a corrosive acid. When the two meet, the sodium atom loses its outer electrons and turns into sodium ions, while the hydrogen ions in hydrofluoric acid gain electrons and turn into hydrogen atoms, which combine in pairs to form hydrogen gas to escape. This reaction is violent, often accompanied by heat and luminescence.
To make its product, you need to choose a strong and corrosion-resistant container to prevent the erosion of hydrofluoric acid. Put an appropriate amount of hydrofluoric acid in it first, and the action should be slow to avoid the acid splashing out and hurting people. Then, take a sodium block with forceps and cut an appropriate amount. The size of the sodium block depends on the amount of product required, and it should not be too large, so as not to react too violently and cause danger. Wipe the kerosene on the surface of the sodium block with filter paper and quickly put it into the hydrofluoric acid. In an instant, the solution can be seen rolling, and bubbles can pop up violently, which is the appearance of hydrogen generation.
After the reaction is completed, sodium fluoride remains in the solution. If you want to obtain pure sodium fluoride solids, you can put the resulting solution in an evaporation dish, heat it slowly over low heat, and gradually evaporate the water. When a large number of crystals precipitate, remove the fire source, and use the residual heat to evaporate to obtain sodium fluoride products. The whole process must be strictly followed by operating procedures and well-protected to ensure safety.

Sodium hydrofluoride when using what are the precautions

When sodium and hydrofluoric acid interact, many precautions need to be kept in mind.

First, the reaction between the two is violent and extremely dangerous. Sodium is an extremely active metal that reacts violently in contact with water, and hydrofluoric acid is extremely corrosive. When the two meet, the reaction is rapid, or it may cause explosion, splashing and other dangerous situations. Therefore, when operating, it must be in a well-ventilated environment, led by experienced and skilled people, and complete protective equipment must be worn, such as acid and alkali protective clothing, protective gloves, protective masks, etc., to prevent the reaction products from harming the body.

Second, for the reaction device, it must be carefully selected and installed. It is necessary to use a device made of materials that can withstand a certain pressure and corrosion, and the connection part should be firmly sealed to prevent gas leakage and liquid leakage. During the reaction process, pay close attention to the pressure and temperature changes of the device. If there is any abnormality, take immediate countermeasures.

Third, strictly control the proportion of reaction materials and the order of addition. According to the established experimental procedures or process requirements, accurately measure the amount of sodium and hydrofluoric acid. Generally, hydrofluoric acid is placed in a suitable container first, and then slowly add sodium to prevent the immediate reaction from being too violent.

Fourth, the post-reaction treatment cannot be ignored. After the reaction is completed, the remaining materials should be properly disposed of and should not be dumped at will. The fluorine-containing waste liquid needs to be specially treated and can be discharged after reaching the standard to prevent environmental pollution. Thoroughly clean the reaction vessel to remove residual corrosive substances to ensure safe use next time.

In short, the interaction of sodium and hydrofluoric acid must be done with caution, follow the standard operating procedures, and pay attention to every detail to ensure the safety of experiments or production.

What is the market price of Sodium hydrofluoride?

Sodium (Sodium) and hydrofluoric acid (hydrofluoric acid, more accurately expressed as hydrofluoric acid, that is, HF aqueous solution) in the market, the price varies due to many factors.

Let's talk about sodium first, sodium is mostly sold in the form of metal sodium in the market. Its price is significantly affected by purity. If the purity is quite high, it can reach 99.9% and above. Due to difficult preparation and complicated process, the price is often high. Generally speaking, the price per kilogram of such high-purity metal sodium may be hundreds or even thousands of yuan. If the purity is slightly lower, in industrial use scenarios, such as used in some metallurgical processes as a reducing agent, the purity is about 95% - 98%, and the price may range from tens of yuan to hundreds of yuan per kilogram. In addition, market supply and demand conditions also affect its price. If the industry's demand for sodium surges during a certain period of time and output is limited, the price will rise; on the contrary, if demand is weak, the price may decline.

Look at hydrofluoric acid again. Hydrofluoric acid is priced differently according to concentration differences. Common industrial grade hydrofluoric acid, with a concentration of about 40% - 70%, is mainly used in glass etching, metal surface treatment and other fields. Due to its wide range of uses and large output, the price per kilogram is roughly in the tens to tens of yuan. If it is electronic grade hydrofluoric acid, the purity requirements are extremely high, and the impurity content needs to be strictly controlled. It is used in high-end fields such as semiconductor manufacturing. Due to the complex production process and strict quality control, the price is much higher than that of industrial grade, and the price per kilogram may reach hundreds of yuan or even higher. Similarly, market supply and demand have a significant impact on the price of hydrofluoric acid. For example, the expansion of the semiconductor industry has greatly increased the demand for electronic grade hydrofluoric acid, and the price will rise.