Elemental analysis absorbent is a chemical reagent used in elemental analysis, mainly by reacting with target elements in the sample to generate specific absorbents or precipitates, thereby assisting or enhancing the analysis process. These absorbents can improve the accuracy and sensitivity of elemental analysis, especially in spectral analysis, commonly used to increase the absorbance of certain elements in the sample, ensuring higher detection accuracy.
Main types and applications:
Separate absorbent:
Used to separate interfering elements from samples and reduce the influence of coexisting elements on analysis results.
For example, sodium phosphate and fluoride absorbents are used to separate heavy metal elements.
Sensitizing absorbent:
Used to enhance the absorbance or fluorescence signal of target elements and improve the sensitivity of analysis.
For example, certain organic solvents or complexing agents can form complexes with metal ions to improve the response value of analysis.
Precipitation absorbent:
Used to precipitate the target element from the solution through precipitation reaction, reducing the interference of other elements on absorption.
For example, precipitants such as hydroxides and sulfides are used to remove impurities from complex samples.
The determination principle of elemental analysis absorbents usually involves quantitatively analyzing the content of elements in the sample through absorption spectroscopy. This method is based on the principle that matter absorbs light at specific wavelengths. The specific steps include:
Sample preparation: The sample to be tested is subjected to appropriate processing, usually in the form of dissolution or decomposition into a solution, for analysis.
Light source: Use a specific wavelength light source (such as flame light source, graphite furnace light source, etc.) to illuminate the sample solution.
Element absorption: Elements in the sample absorb light of specific wavelengths, and different elements have different absorption wavelengths.
Photoelectric detection: Detect the light intensity after passing through the sample through a photoelectric detector, and compare the difference in light intensity before and after irradiation.
Quantitative analysis: Based on the relationship between absorbance and element concentration in the sample (usually determined by a calibration curve), the concentration of elements in the sample can be calculated.
This method is commonly used for the analysis of metal elements and inorganic substances, such as quantitative detection of copper, iron, lead and other elements.