Question
How is a Lachat Cadmium Column for Nitrate determination checked for efficiency?
Summary
Procedure to check cadmium column efficiency
Answer
Column, Cadmium, for Nitrate determination (Product # 50237A)
Column Efficiency
Before running samples, column efficiency can be determined as follows:
1. Calibrate with nitrate (NO 3 ) standards.
2. Run a known concentration of nitrite (NO 2 ) standard as N.
3. Run a matching concentration of NO 3 standard as N.
The column efficiency is determined by the equation:
where:
E = column efficiency
[NO 3 ] = concentration of nitrate standard
[NO 2 ] = concentration of nitrite standard
If the efficiency is less than 90%, do not use the cadmium column see the article What are possible causes of low nitrate efficiency when running Lachat nitrate/nitrite methods?
If the article on possible causes do not help resolve the low efficiency contact Lachat technical support or the local distributor.
Column Efficiency
Before running samples, column efficiency can be determined as follows:
1. Calibrate with nitrate (NO 3 ) standards.
2. Run a known concentration of nitrite (NO 2 ) standard as N.
3. Run a matching concentration of NO 3 standard as N.
The column efficiency is determined by the equation:
where:
E = column efficiency
[NO 3 ] = concentration of nitrate standard
[NO 2 ] = concentration of nitrite standard
If the efficiency is less than 90%, do not use the cadmium column see the article What are possible causes of low nitrate efficiency when running Lachat nitrate/nitrite methods?
If the article on possible causes do not help resolve the low efficiency contact Lachat technical support or the local distributor.