Many people are not very clear about the preparation and calibration of metal standard solutions, the following small edition of Bolinda to give you a detailed introduction.

Preparation and calibration of metal standard solutions:

1. Preparation of water-soluble metal standard solution

Directly with acid cleaning or polishing of high purity metal wire, rod, sheet, or high purity metal oxide, or superior purity (spectral grade, reference purity) metal salts, dissolved in high purity acid, plus double distillation deionized water to prepare acid water soluble metal standard solution.

2, non-aqueous metal standard solution

Dissolve metallometallic compounds of high purity or superior purity in suitable high purity organic solution; (preferably C or C aliphatic esters or ketones, C alkanes) are prepared into non-aqueous metal standard solutions, or metal ions are converted into extractable complexes, extracted with suitable high-purity organic solutions, and the content of metal ions in the organic phase is indirectly calibrated through its content in the determination of the water phase.

3. Standard reserve liquid

The standard solution prepared is generally 1.00mg/1.0m1, or 100μg/1.0ml, with an acid content of 10%. For example, with high pressure polyethylene bottle and sealed, can ensure 2a at room temperature,4℃ refrigerator refrigeration 4a, its content can remain basically unchanged.

4, standard working liquid with storage liquid

Dilute into the acidity of the working liquid solution is 5%, choose a hard glass bottle suitable for storing the acidity of the solution is 5%, and its content can be stored for 2 to 3 months at room temperature.

5. The standard working liquid is diluted into the working liquid

When the acidity of the solution is 1%, the glass bottle remains unchanged for 1 week; The acidity of the solution is 0.2% acidity, and the glass bottle can only be used on the same day, such as the high-pressure polyethylene bottle can be stored for 1 week, and the tetrafluoroethylene bottle can be stored for about 2 months.

6, acidified metal standard liquid

When the metal standard solution is acidified with hydrochloric acid to pH=2.0, the polyethylene container is used to hold it, which can ensure that the metal elements are not lost. The concentration of the stored liquid should be above 1.0mg/ml; The value of elements in hard glass bottles and plastic bottles, which are not acidified by hydrochloric acid than the loss of acidification by hydrochloric acid is less; The maximum use time should not exceed 1 ~ 2d when the concentration is <1.0mg/ml.

The above content is the introduction of the preparation and calibration of metal standard solution, self-formulated standard solution as a working standard solution, generally used for daily inspection analysis, not for other test results with legal effects, unless it can be proved that its nature as a measurement reference standard will not fail.