SOP for CHN Analysis Using Flash EA 1112 Elemental Analyzer

Ver. 3-2010, Jian Shi and Mirvat Ebrik

The following is a guide to the Flash EA 1112 Elemental analyzer.

Initial Settings (Please skip this unless you are creating a new configuration):

1. On the “File” drop down menu, select “Instrument Name and Configuration”

2. Press the “Elemental Analyzer Setup” button and verify that the line frequency is at 60 hertz, and also that the proper com port is selected. Press “OK”

3. Under the Analytical Configuration box select the configuration that you will be running. (i.e. if you are running for nitrogen and carbon, select the HCN configuration.)

4. Press “OK”. Your system is now ready to load in the default method for your analysis.

Prepare Analyzer for Run

Turn the analyzer on (on the right side on the back)
Open the He tank (around 58psi) with a ½ turn
Open the O2 tank (around 48psi) with a ½ turn
Open software for the analyzer
Double click on “Eager Experience”
Double click on “EA1112 Analyzer 1”
You need to set up the furnace and the oven temperature.
Go to Edit → Click on “Edit Elemental Analyzer Parameters”
Click on furnace 900 ºC
Click on the oven 65 ºC then send then “OK”
Click “Send”

Leaking Test

Click on “View” à “View element analyzer status”
Click on “General” tab, verify if the actual temperature equal to the set point 900
If yes, click on “Special function” tab
Click on “Leak test”
Click on “Start”
Click on “Yes”
When the “carrier flow” reaches 0, it should take around 70-100sec (if it takes more than 150 sec then there is a leak).
Click on “Done”

Calibration and Analysis:

1 Press the “Edit Sample Table” icon.

2 Press the “Fill Sample Table” icon.

Select a unique name for the “File Name” (i.e. 1May10, or another name that will help you organize when the samples were run.) Select the “Number of Samples” you want filled in and press “OK”

Sample Name / File name / Type / Std Name / Weight
Name001 / 1May06 / Unk / 0 / 5mg
Name002 / 1May06 / Unk / 0 / 5mg
Name003 / 1May06 / Unk / 0 / 5mg

The Eager Experience software will index the “File Name” and “Sample Name” according to the number of samples you have selected.

3 Set up your Calibration.

Bypass: Tin or silver weigh cup containing some standard to produce a chromatogram so you can adjust retention time and see if chromatogram looks good before running your calibration.

Blank: Empty tin or silver cup. The blank establishes a baseline for your calibration. If you have a high nitrogen peak in your blank, stop your analysis and troubleshoot the blank according to the operator’s manual.

Standard: The material you will weigh out that has known and reliable data. The standard is your basis of the calibration.

Check Standard: A standard run as an unknown to check your calibration.

4 The following is a typical example of a k-factor calibration in your sample table:

Sample Name / File name / Type / Std Name / %N
Bypass / 1May10 / Bypass
Blank / 1May10 / Blank
Stand / AA1May10 / Std / Aspartic Acid / 10.112
Stand / AA1May10 / Std / Aspartic Acid / 10.112
Chk / DDOT / Unk

*L-aspartic acid standards: N: 10.52% C: 36.09%

*DDOT standard: N: 4.84% C: 70.56%

5 Insert a blank line on the sample table after the bypass, blank and calibration series, so you can stop the sequence after each to check if each is valid.

6 Press “OK” to exit the sample table.

7 At this point save your method. To save your method, use the “File” drop down menu and select “Save Method”. It will bring up the system defined methods. Use the up folder icon to get out of that screen. (Note: the Eager Experience software will not let you overwrite the system defined methods.) Create a new folder and give it a name. Open it and save your method into it, giving your method a new name.

8 Click the “Run” drop down menu and select “Start Sequence of Samples”. Click “OK” and your samples will start running.

9 To view the sample, click “View” and select, “Sample Being Acquired”. This will bring up your real time plot and you will be able to see the chromatogram as it is running.

10 After your calibration is finished, click on the “Summarize Results” icon to view your data. If your calibration is good your “Check Standard” should be ±0.2 of the expected value. If they are not, change one of your standards to an unknown in your sample table then use the “Recalculation” drop menu and select “Recalculation” to recalculate the sequence. (Making sure that you have Reintegrate and Identify Peaks checked.)

11 After you have a good calibration, check your sample table and remove the blank line and fill in the rest of the samples you have to analyze. Insert a blank line at the end of your sequence to stop the instrument from continuing on with the run.

12 Go to the “Run” Drop down menu and select “Run Sequence”. The instrument will run all the samples that you put in the sample tray in accordance with your sample table.

13 If you do have a lot of samples to run, please insert a “Check Standard” every 10 to 15 samples to verify that the calibration is still good.

Post Analysis:

14 After your run is completed you can go into the summary table and view your results.

15 In the summary table you can group like samples together by assigning the like sample a group number. (This is done if you have duplicates or triplicates of the same sample to view the elemental average, percent RSD, and variance of the like samples.)

16 To display the data for a specific group, place the cursor on the group and select the drop down screen you are looking for the element that you want averaged.

17 To print your data, select the “Print” drop down menu and select “Print All Group”.

This will bring up the print screen and select to “Print By Peaks”.

18 If you have no more samples to run place your instrument into standby.

Elemental Analyzer Operation Checklist

Start Up

1) Fill out the user log

2) Turn on Flash EA 1112 Power (on back of machine)

3) Turn Gases on: O2 (40-60 psi) and He (40 psi)

4) Turn on Computer (-login: -Password: )

5) Load Eagar1112 Software

6) In the main menu select View then View Maintenance option to see if there is any maintenance required before you start the system – if the number of runs until warning message is less than your total samples + standards, please proceed to replace reactors or filter.

7) Click on General Use instrument icon; In the main menu select File and then the option Instrument Configuration; In the section Analytical instrument configuration check the NC configuration; Press the Elemental Analyzer setup button–

Serial port: COM1 Line frequency: 60 Hz

TCD settings Source = Internal & Polarity = Positive

Sampler setting select EA MAS sampler

8) Load your method or system defined method

9) Send parameters to the instrument (~ 50 min for furnaces to reach the temperature setting)

10) Once the instrument LED is green the system ready

In the main menu select View and then the option View Elemental Analyzer Status

** Run Leak test (under Special Functions).

Carrier & Reference Flows will decrease to 5ml/L or less (~ 300s; ~ 3 & 0 ml/min).

** Run Auto-Adjust Level at 1000 μV (under Detector) –

At the end of the operation, the value 1000 is set representing the analysis starting point.

Running Samples (Ret. Time N: 110 C: 190 blank N: 0-2000 μV/s)

11) Load samples, one in each compartment of autosampler

12) Replace lid

*suggestion: run check standard every 20 – 30 samples

Shut down TCD ON = Gas ON TCD OFF = Gas OFF

13) Turn off oven, reactors and TCD by deselecting the parameters and sending to instrument (check instruments to make sure lights are off)

14) Turn off the O2 and He gases

15) Exit the Eagar Software

16) Turn off the computer

**Do not turn off the instrument’s main power until cool (several hrs)

Packing a New Reactor:

Figure 1. Reactor for CHN analysis

* Potential hazards: glass wool can cause irritation when contact with skin; glass wool is a “Category 3 carcinogen”, which means not classifiable as to its carcinogenicity to humans.