Page History

Instrument

Specification

Method

Combustion/nondispersive infrared gas analysis

Combustion temperature

680°C

Measurement range

4 ppb to 4000 ppm

Anaysis time

2–3 min each for TC and IC

Repeatability

<2000 ppm: 1% of full scale
2000–4000 ppm: 2% of full scale

Sample introduction

Automatic injector

Injection volume

50–2000 µL

Ambient temperature

5°–35°C

Dimensions

480 mm W x 520 mm D x 480 mm H

Weight

~46 kg

Step

Action

1

From the TOC Control screen select File > Open Sample Table and open a new or previously saved calibration Sample Table (Fig 8).

1

Click in the first line of the Sample Table and select Edit > Insert Standard.

2

On the TOC Control screen toolbar, select View > Calibration Curve List.

3

On the Calibration Curve List dialog box, select New (Fig 9).

4

On the Conditions tab (Fig 10), enter the following:

• Title and File Name for the calibration
• Analysis Type (TC or IC)
• Change Calculation Method to Lin. Regression without Zero Shift (FIG).
• The Range and Injection Volume fields will be autofilled after completing information in the Data tab.

5

Select the Data tab and enter information requested into the data table.

6

Click OK and save the calibration information and Yes to use as method default parameters.

7

Save the Sample Table.

Step

Action

1

Place calibration curve standards in autosampler spaces S1–S8.

2

Verify status of instrument and baseline: View > Background Monitor then close Background Monitor screen.

3

Select Measure > Start or click Start on the instrument control bar. When the Standby screen opens, select Keep Running and click OK.

4

To monitor the status of the measurements, select View > Realtime Window or select Realtime Window on the toolbar.

5

When the calibration runs are complete the instrument status bar will indicate Ready.

Step

Action

1

Select View > Calibration Curve or click the Calibration Curve button on the toolbar.

2

Select the Curve tab to see the curve data in graphical format. . [Author: Need a screen shot of this.]

3

Check the correlation coefficient (R²), which was calculated using the linear relationship of the concentration vs. area. R² > 0.995 indicates an acceptable calibration.

4

Select the Data tab to view standard deviation and coefficient of variation statistics. [Author: Need screen shot.]

5

Individual peaks or injections can be viewed using View > Peak Profile > Display.

6

If the calibration is acceptable, specify the calibration file (CAL) name in the method and close the Calibration window.

Step

Action

1

Run a midpoint curve standard as an "unknown" sample in the Sample Table.

2

Apply the calibration curve to calculate the sample results.

3

Open View > Injection Table or click the Injections button on the toolbar to examine the sample results in the Concentration column and the result of the Outlier Test. For acceptable calibration verification, CV should be >0.90.

4

Close the Injection Table screen.

Step

Action

5

Set up hardware (see Setting up the Sample Table for Calibration Curve)

6

Set up software (see Preparing TOC Software )

7

Set up autosampler (see Preparing the Autosampler)

8

Set up sample table (see Setting up a Sample Table and Selecting a Calibration Curve)

9

Run samples (see Running Samples)

Step

Action

1

Make sure tubing and cables are connected properly to the instrument.

2

Check compressed air feed line (65–80 psi) for the Gas Generator (if using an ultra-high purity air tank the delivery pressure be set to 80 psi (not to exceed 100 psi).

3

Check that the Gas Generator is in ready condition. THC light green and no CHECK SYSTEM/ OVERFLOW lights on. [Author: Need photo of green light on Gas Generator.]

4

Fill the humidifier with distilled water until the water level is between the white lines. Make sure the rubber stopper is fully plugged in.

5

Fill IC vessel with 75–100 mL of 25% phosphoric acid solution.

6

Make sure all drain lines have a negative slope alignment. Empty the drain container, if required.

7

Check position of three-way cock arm. The cock arm should be in the left position (Fig 4).

8

Ensure TOC main power switch is turned on and black switch on front top right side (behind instrument door) is in PC CONTROL position.

Step

Action

1

Click on the TOC Control icon on the computer desktop (see #1 on Fig 11). Type DAQ for username and password to open the TOC Control screen.

2

From the Toolbar on the TOC Control screen, select Measure > Connect (#3 on Fig 11), and at the bottom of the Control screen click the TOC button (#4 on Fig 11).
The message bar (#5 on Fig 11) should say Connected.

3

Check the carrier gas flow meter and pressure gage on the front panel of the TOC analyzer.

[Author: Need a photo of this meter and pressure gage.]

Flow should be 150 mL/min, and pressure should be ~450 kPa. Adjust flow or pressure to target values using the Carrier gas pressure controller and Carrier gas flow controller next to the flow meter (see Fig 4).

On the TOC Control screen, select View > Background Monitor (#6 on Fig 11) to open a background window.

Wait ~2 min and then make sure all parameters read OK on screen (exception: oven temperature will take ~30 min to reach 680°C).

[Author: Need a screen shot of the Background window.]

Close the Background window.

On the TOC Control screen select Options > Instrument Conditions (#7 on Fig 1) to set up and/or verify TOC, ASI, and RS232 settings as follows:

TOC

• Furnace = on
• Auto ranging = on
• Inj volume = on
• Auto regenerating = on
• Syringe size = 250 µm

ASI

• ASI used = on
• High sensitivity vials = on
• Rinse = on
• No. of washes = 4

RS232

• RS232 = COM1
• Baud rate = 2400
• Parity = none
• Stop bits = 1

Step

Action

1

Fill autosampler rinse bottle (Fig 5) with fresh zero water.

Fill high-sensitivity 50 mL autosampler glass vial with zero water and place it to S1 tray position. Remove tray cover or make sure it's in the correct position.

• Each vial in the autosampler tray must be filled to the top and covered immediately with wax paper or sealed with special caps to prevent CO₂ penetration. After the sealed surface is pierced by the autosampler needle, the vials will remain usable for only a limited time (usually a few hours).

3

Remove bubbles from the syringe (Detect Zero point): on the TOC Control screen select Options > Maintenance > Zero point detection.
The ASI arm and tray will start moving and the syringe/4-port valve will perform the bubble removing procedure.

Step

Action

1

From the TOC Control screen select File > Open Sample Table to create a new Sample Table (#8 in Fig 11) or open an old Sample Table (#9 in Fig 8).

2

Fill in the Sample Table with sample type, name, ID, and analysis.

3

To specify a method on the Sample Table, select View > Methods on the TOC Control screen to open a saved method or create a new method.

4

Fill in information on the General and Method tabs of the Method screen (Fig 12).

5

To specify a calibration curve to apply to the samples, select View > Calibration on the TOC Control screen to open a dialog box showing a list of calibration curves saved in the CALIBR folder (Fig 9).

6

On the Calibration Curve List dialog box, click Open to select a saved calibration curve.

7

Save the Sample Table.

Step

Action

1

Load the sample vials into the autosampler in positions that correspond to the Sample Table.

2

Verify status of instrument and baseline: View > Background Monitor, then close Background Monitor screen.

3

Select Measure > Start or click Start on the instrument control bar. When the Standby screen opens, select Keep Running and click OK.

4

To monitor the status of the measurements, select View > Realtime Window or select Realtime Window on the toolbar.

5

When the sample runs are complete the instrument status bar will indicate Ready.

6

Sample results calculated from the loaded calibration file will display in the Sample Table Mean Area and Result columns.

Step

Action

1

Place vials filled with zero water in autosampler positions S1–S4.

2

On the autosampler control panel, open the Maintenance screen and select TC Blank Check.

3

The autosampler injects S1 twice, S2 three times, S3 three times, and S4 twice and then returns to Home.

Analysis

Component

Definition

Unit

TOC

carbon_total

Concentration

ppm

inorganic_carbon_total

Concentration

ppm

organic_carbon_total

Concentration

ppm

run_test

link to calibration test

TOC_QAQC

carbon_total

Concentration

ppm

inorganic_carbon_total

Concentration

ppm

organic_carbon_total

Concentration

ppm

run_test

link to calibration test

cal_filename

calibration file

method_filename

run_filename

Step

Action

1

Select Options > Maintenance > Mechanical Check > TOC.

2

Move the syringe plunger up and down using the plunger height control on the left while changing the position of the 4-port valve to Sample, TC port, or IC port.

3

When the sample goes to the TC/IC waste line, do not bring the syringe plunger all the way up.

Step

Action

1

Place a vial containing 2 mM HCl in position S1.

2

Open the autosampler Maintenance screen and select Regeneration of TC Catalyst.

3

The sampling needle moves to the S1 vial then to the rinse water receptacle and rinses the injection needle 3 times.