07,02,2026 15 views
With the rapid development of spectroscopic analysis instruments, some colorimetric dishes such as trace, semi trace, fluorescence, etc. continue to appear, which require higher requirements for their use, maintenance, and cleaning. Generally, it is disposable abroad, but in China, it is reused to save costs and reduce expenses. How to clean the colorimetric dish? It can only be cleaned using various reagents and methods that can dissolve and neutralize them. In principle, the structure and transparency of the colorimetric dish should not be damaged; Secondly, neutralization and dissolution methods can be used to achieve the effect of keeping the colorimetric dish clean as before. The cleanliness of the colorimetric dish in a spectrophotometer is one of the factors that affect the accuracy of the measurement. Therefore, it is necessary to pay attention to choosing the correct cleaning method.
Below are several cleaning methods:
1. For example, if the test solution is acidic, wash it with a weak alkaline solution if it is not clean. If the test solution is alkaline, wash it with a weak acidic solution if it is not clean. If the test solution is organic, wash it with an organic solvent such as alcohol if it is not clean.
2. The principle of choosing a colorimetric dish washing solution is to achieve good stain removal effect, not damage the colorimetric dish, and not affect the measurement. 3. The commonly used chromic acid washing solution should not be used for washing colorimetric dishes, because colorimetric dishes with water in the solution may sometimes generate local heat, causing the bonding surface of the colorimetric dish to crack and be damaged. At the same time, the colorimetric dish washed with washing solution may still have trace amounts of chromium remaining, which can be absorbed in the ultraviolet region and therefore affect the determination of chromium and other related elements. It is generally recommended to use a mixed solution of nitric acid and hydrogen peroxide (5:1) for soaking and washing, followed by rinsing with water.
4. For colorimetric dishes that are difficult to clean by general methods, the following two methods can be adopted.
A、 First, immerse the colorimetric dish in a solution of sodium carbonate (20 g/L) containing a small amount of anionic surfactant, rinse with water, and then immerse it in a mixed solution of hydrogen peroxide and nitric acid (5:1) for half an hour.
B、 Soak in a mixed solution of hydrochloric acid, water, and methanol (1:3:4) in a fume hood for no more than 10 minutes. C. The colorimetric dish cannot be washed with alkaline solution, nor can it be brushed with a hard cloth or brush.
