How to clean plastic utensils in the laboratory

Update:14-05-2021
Summary:

Usually use neutral detergent to clean plastic products […]

Usually use neutral detergent to clean plastic products, and then rinse with tap water or distilled water; ultrasonic cleaning method is also suitable for cleaning plastic products; of course, you can also choose some special cleaning methods according to the nature of plastic surface dirt and the performance of plastic products.


1. Cleaning of organic matter
Soaking with chromic acid lotion can also remove organics on the plastic surface, but due to its strong oxidizing properties, it may cause plastic products to become brittle, so the soaking time should not exceed 4 hours; in addition, sodium hypochlorite solution can also remove organics at room temperature.
2. Cleaning of grease
If there is grease on the surface of the plastic product, it is usually washed with a weak alkaline detergent first, then rinsed thoroughly with tap water, and finally rinsed with deionized water. PC, PP and PS plastic products can only be washed manually with neutral detergents, or they can be washed with ethanol. Other organic solvents or solvents will also damage these plastic products. For plastic products that can be cleaned with organic solvents, the time for soaking and cleaning should not be too long to prevent expansion and deformation. The plastic products after cleaning with solvent should be rinsed repeatedly with tap water, and then rinsed with deionized water for several times. .


3. Cleaning of trace elements
Plastic products usually contain trace metal elements. Common elements are Na, Ca, Fe, Al, Cu, Zn, Mg, Pb, Si and B. In order to prevent the dissolution of these elements from affecting the experimental results, you can soak in 1mol/L hydrochloric acid solution before use, and then rinse with deionized water; for ultra-clean experiments, you can soak in 1mol/L nitric acid solution after soaking in hydrochloric acid solution ( The total soaking time should not exceed 8 hours), and then rinse with deionized water. If traces of metal organics are adsorbed on the surface of the plastic product, the surface can be cleaned with ethanol, alkali or chloroform first, then soaked with 1mol/L hydrochloric acid solution, and finally rinsed with deionized water, and dried for later use.