Platinum, also known as platinum, is more expensive than gold and is often used due to its many excellent properties. Platinum has a melting point of up to 1774 ℃, stable chemical properties, and does not undergo any chemical changes or absorb moisture after being burned in air. Most chemical reagents have no corrosive effect on it.

1. Characteristics:

The ability to withstand corrosion from hydrofluoric acid and molten alkali metal carbonates is an important property of platinum that distinguishes it from glass, ceramics, etc. Therefore, it is often used for precipitation, burning, weighing, hydrofluoric acid melting samples, and carbonate melting treatment. Platinum is slightly volatile at high temperatures and needs to be corrected after prolonged burning time. Platinum with an area of 100cm2 loses approximately 1mg after being burned at 1200 ℃ for 1 hour, while platinum remains virtually non-volatile below 900 ℃.

2. The use of platinum containers should follow the following rules:

(1) Strict regulations must be established for the collection, use, consumption, and recycling of platinum.

(2) Platinum has a soft texture, even alloys containing a small amount of rhodium iridium are relatively soft, so do not apply too much force when taking platinum containers to avoid deformation. When removing the melting block, sharp objects such as glass rods should not be scraped from the platinum container to avoid damaging the inner wall; Hot platinum vessels should not be suddenly placed in cold water to avoid cracking. A deformed platinum crucible or vessel can be corrected using a water mold that matches its shape (but the brittle platinum carbide part should be uniformly corrected with force).

(3) Platinum vessels should not come into contact with any other metals during heating, as platinum is prone to form alloys with other metals at high temperatures. Therefore, platinum crucibles must be placed on platinum tripods or supports made of ceramics, clay, quartz, or other materials for burning. They can also be heated on electric heating plates or electric furnaces with asbestos pads, but cannot directly come into contact with iron plates or electric furnace wires. The crucible pliers used should be wrapped with platinum heads, and nickel or stainless steel pliers can only be used at low temperatures.

3. Cleaning method for platinum vessels:

If platinum vessels have spots, they can be treated separately with hydrochloric acid or nitric acid first. If it is ineffective, potassium metabisulfate can be melted in a platinum vessel at a lower temperature for 5-10 minutes. After pouring out the melt, the platinum vessel can be soaked in hydrochloric acid solution. If it is still ineffective, sodium carbonate melting treatment can be tried again, or wet fine sand (passing through a 100 mesh sieve or 0.14 mm sieve) can be gently rubbed for treatment.