Common cleaning solutions for glassware

One: Strong acid oxidant lotion
The strong acid oxidant lotion is made up of dichromate and concentrated sulfuric acid. K2Cr2O7 has strong oxidizing ability in acidic solution, and has little corrosive effect on glass instruments. So this lotion is widely used in the laboratory. The preparation concentration varies from 5 to 12%. The preparation method is roughly the same: take a certain amount of K2Cr2O7, first dissolve it with about 1~2 times of water, after a little cooling, slowly add the required volume of industrial concentrated H2SO4 to the K2Cr2O7 insoluble solution, and stir with a glass rod while pouring , and be careful not to spill, mix well, and after cooling, put it into a lotion bottle for use. The newly prepared lotion is reddish-brown and has strong oxidizing ability. When the lotion turns black-green after a long time, it means that the lotion has no oxidative cleaning power.
Two: Alkaline lotion
Alkaline lotion is used to wash instruments with oily dirt. This lotion is used for a long time soaking method or soaking method.
Wear latex gloves when removing the instrument from the alkaline wash to avoid burning the skin.
Commonly used alkaline washing solutions are: sodium carbonate solution, sodium bicarbonate solution, sodium phosphate solution, disodium hydrogen phosphate solution, etc.

Three: alkaline potassium permanganate lotion
Use alkaline potassium permanganate as the washing liquid, the effect is slow, and it is suitable for washing oily utensils.
Preparation method: take 4 grams of potassium permanganate (KMnO4) and dissolve it in a small amount of water, then add 100 mL of 10% sodium hydroxide (NaOH).
According to the nature of the dirt on the utensils, directly soak or soak the utensils with concentrated sulfuric acid (HCL) or concentrated sulfuric acid (H2SO4), concentrated nitric acid (HNO3).
The soda ash washing solution is mostly made of more than 10% concentrated caustic soda, potassium hydroxide or sodium carbonate solution to soak or immerse the utensils.
Four: organic solvent
Utensils with fatty dirt can be scrubbed or soaked with organic solvents such as gasoline, toluene, xylene, acetone, alcohol, chloroform, ether, etc.
However, the use of organic solvents as washing liquid is more wasteful, and the large-scale instruments that can be washed with a brush should use alkaline washing liquid as much as possible.
Only small pieces or specially shaped instruments that cannot be brushed should be washed with organic solvents.