1. Different materials: Quartz crucible is glass; du po […]
1. Different materials:
Quartz crucible is glass; du porcelain crucible is ceramic.
2. Different acid and alkali resistance:
Quartz crucibles are resistant to acid and alkali, but hydrofluoric acid cannot be used; dao porcelain crucibles are not resistant to strong alkalis.
3. Different high temperature resistance:
Porcelain crucibles can withstand high temperatures up to 1200 degrees Celsius; quartz crucibles are divided into milky white and transparent, milky white crucibles are used below 1200 degrees, and transparent crucibles are used below 1400 degrees.
Note on the use of porcelain crucible:
1. The maximum heat resistance is about 1200 degrees Celsius.
2. Suitable for melting samples of acidic substances such as potassium pyrosulfate.
3. Generally, it cannot be used for melting with alkaline substances such as sodium hydroxide, sodium peroxide, sodium carbonate, etc., to avoid corrosion of the porcelain crucible. Porcelain crucible should not be in contact with hydrofluoric acid.
4. Porcelain crucible can generally be cleaned by boiling dilute hydrochloric acid.
5. Porcelain crucibles can be divided into middle wall crucibles, low-wall crucibles, high-wall crucibles, plain crucibles, volatile crucibles, tight crucibles, roca crucibles, double-layer crucibles, ancient crucibles, fine-pored crucibles, infrared carbon and sulfur Crucible, free expansion coefficient crucible, etc.
6. Ceramic has water absorption. Therefore, in order to reduce errors, the crucible should be strictly dried before being weighed on an analytical balance.