Chloride, 8113
Chloride
DOC316.53.01017
Mercuric Thiocyanate Method
Method 8113
(0.1 to 25.0 mg/L Cl–) Scope and Application: For water and wastewater
Test preparation
How to use instrument-specific information The Instrument-specific information table displays requirements that may vary between instruments. To use this table, select an instrument then read across to find the corresponding information required to perform this test.
Table 1 Instrument-specific information Instrument
Sample cell
Cell orientation
Adapter
DR 5000
2495402
Fill line faces user
A23618
DR 2800
2495402
Fill line faces right
—
DR 2700
2495402
Fill line faces right
—
DR/2500
2427606
—
—
DR/2400
2427606
—
—
Before starting the test: Filter turbid samples with moderately rapid filter paper and a funnel before analysis. Both the sample and the blank will contain mercury (D009) at a concentration regulated as a hazardous waste by the Federal RCRA. Do not pour these solutions down the drain. Refer to the MSDS sheet for safe handling and disposal of hazardous waste. Gloves are recommended.
Collect the following items: Description
Quantity
Ferric Ion Solution
1 mL
Mercuric Thiocyanate Solution
2 mL
Deionized Water
10 mL
Sample Cells (see Instrument-specific information)
2
Pipet, TenSette®, 0.1 to 1.0 mL
1
Pipet tips for 0.1 to 1.0 mL TenSette pipet
2
See Consumables and replacement items for reorder information.
Chloride Page 1 of 6
Chloride Mercuric Thiocyanate method for Chloride
Stored Programs 70 Chloride Start
1. Select the test. Insert an adapter if required (Instrumentspecific information).
2. Prepared Sample: Fill a sample cell with 10 mL of sample.
3. Blank Preparation: Fill another sample cell with 10 mL of deionized water.
4. Pipet 0.8 mL of Mercuric Thiocyanate Solution into each sample cell.
6. Pipet 0.4 mL of Ferric Ion Solution into each sample cell.
7. Swirl to mix. An orange color will develop if chloride is present.
8. Start the instrument timer.
Refer to the user manual for orientation.
5. Swirl to mix.
Zero
9. Within five minutes after the timer expires, wipe the blank and insert it into the cell holder.
Chloride Page 2 of 6
10. ZERO the instrument. The display will show: 0.0 mg/L Cl–
A two-minute reaction time will begin.
Read
11. Wipe the prepared sample and insert it into the cell holder.
12. READ the results in mg/L Cl–.
Chloride
Interferences Table 2 Interfering substances and levels
1
Interfering substance
Interference levels and treatments
Extreme pH
Should be about pH 2 after adding reagents. If the sample is strongly acidic or alkaline, adjust a portion of sample before testing to a pH of about 7. Use either 5.0 N Sodium Hydroxide Standard Solution1 or a 1:5 dilution of perchloric acid. Use pH paper; most pH electrodes will contaminate the sample with chloride.
See Optional reagents and apparatus.
Sample collection, preservation and storage Collect samples in glass or plastic containers. Samples can be stored for at least 28 days at room temperature.
Accuracy check Required for accuracy check: •
Chloride Standard Solution, 1000-mg/L
•
50 mL mixing cylinders, three
•
TenSette Pipet
Standard additions method (sample spike) 1. After reading test results, leave the sample cell (unspiked sample) in the instrument. 2. Select standard additions from the instrument menu: Instrument
Navigate to:
DR 5000
OPTIONS>MORE>STANDARD ADDITIONS
DR 2800
OPTIONS>MORE>STANDARD ADDITIONS
DR 2700
OPTIONS>MORE>STANDARD ADDITIONS
DR/2500
OPTIONS>STANDARD ADDITIONS
DR/2400
OPTIONS>STANDARD ADDITIONS
3. Default values for standard concentration, sample volume, and spike volumes can be accepted or edited. After values are accepted, the unspiked sample reading will appear in the top row. See the user manual for more information. 4. Prepare three sample spikes. Fill three 50 mL mixing cylinders with 50 mL of sample. Use the TenSette® Pipet to add 0.1 mL, 0.2 mL and 0.3 mL of 1000-mg/L Chloride Standard Solution, respectively, to the cylinders and mix each thoroughly. 5. Analyze a 10 mL portion of each sample spike as described in the Mercuric Thiocyanate method for Chloride test, starting with the 0.1 mL sample spike. Each addition should reflect approximately 100% recovery. 6. Select GRAPH to view the results. Select IDEAL LINE (or best-fit) to compare the standard addition results to the theoretical 100% recovery.
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Chloride Standard Solution Method Required for accuracy check: •
Chloride Standard Solution, 1000-mg/L
•
Volumetric Flask, 500-mL
•
Pipet, Class A glassware
1. Prepare a 20.0-mg/L chloride standard solution. a. Use Class A glassware to pipet 10.00 mL of Chloride Standard Solution, 1000-mg/L, into a 500-mL volumetric flask. b. Dilute to the mark with deionized water. Follow the Mercuric Thiocyanate method for Chloride test. 2. To adjust the calibration curve using the reading obtained with the standard solution, navigate to Standard Adjust in the software. Instrument
Navigate to:
DR 5000
OPTIONS>MORE>STANDARD ADJUST
DR 2800
OPTIONS>MORE>STANDARD ADJUST
DR 2700
OPTIONS>MORE>STANDARD ADJUST
DR/2500
OPTIONS>STANDARD ADJUST
DR/2400
OPTIONS>STANDARD ADJUST
3. Turn on the Standard Adjust feature and accept the displayed concentration. If an alternate concentration is used, enter the concentration and adjust the curve to that value.
Method performance
Program
Instrument
Standard
Precision 95% Confidence Limits of Distribution
70
DR 5000
20.0 mg/L Cl–
17.9–22.1 mg/L Cl–
DR 2800
20.0 mg/L Cl–
17.9–22.1 mg/L Cl–
DR 2700
20.0 mg/L Cl–
17.9–22.1 mg/L Cl–
DR/2500
20.0 mg/L Cl–
18.3–21.8 mg/L Cl–
DR/2400
20.0 mg/L Cl–
18.3–21.8 mg/L Cl–
Program
Instrument
Standard
Portion of curve
Sensitivity Concentration change per 0.010 Abs change
70
DR 5000 DR 2800 DR 2700
20.0 mg/L Cl–
1.0 mg/L
0.1 mg/L Cl–
10.0 mg/L
0.3 mg/L Cl–
20.0 mg/L
0.6 mg/L Cl–
1.0 mg/L
0.11 mg/L Cl–
20.0 mg/L
45 mg/L Cl–
DR/2500 DR/2400
Chloride Page 4 of 6
20.0 mg/L Cl–
Chloride
Summary of method Chloride in the sample reacts with mercuric thiocyanate to form mercuric chloride and liberate thiocyanate ion. Thiocyanate ions react with the ferric ions to form an orange ferric thiocyanate complex. The amount of this complex is proportional to the chloride concentration. Test results are measured at 455 nm.
Consumables and replacement items Required reagents Description
Quantity/Test
Unit
Catalog number
—
100 tests/pkg1
2319800
Chloride Reagent Set, includes:
1
(1) Ferric Ion Solution
1 mL
100 mL
2212242
(1) Mercuric Thiocyanate Solution
2 mL
200 mL
2212129
Water, deionized
10 mL
4L
27256
Quantity/Test
Unit
Catalog number
1
each
1970001
varies
50/pkg
2185696
Unit
Catalog number
500 mL
18349
Unit
Catalog number
16/pkg
1425010
1L
2370853
50 mL
189641
100/pkg
69257
100 tests (50 samples and 50 blanks) using 10-mL cells. 50 tests using 25-mL cells.
Required apparatus Description Pipet, TenSette®, 0.1 to 1.0 mL Pipet Tips, for TenSette Pipet 1970001
Recommended standards Description Chloride Standard Solution, 1000-mg/L Cl–
Optional reagents and apparatus Description Chloride Standard Solution, 10-mL Voluette® Ampule, 12,500-mg/L Cl– Chloride Standard Solution, 100-mg/L Cylinders, mixing Filter Paper, funnel Funnel, poly
75 mm
108368
pair
2410104
Perchloric Acid, ACS
680 g
75765
pH Paper, 1.0–11.0 pH range
5/pkg
39133
1000/pkg
2185628
10 mL
1451538
each
1465100
50 mL
245026
each
2196800
Gloves, chemical resistant, size
9–9.51
Pipet Tips, for TenSette Pipet 1970001 Pipet, volumetric, Class A Pipet Filler, safety bulb Sodium Hydroxide Standard Solution, 5.0 N Voluette Ampule Breaker, for 10-mL ampules 1
Other sizes available
Chloride Page 5 of 6
FOR TECHNICAL ASSISTANCE, PRICE INFORMATION AND ORDERING: In the U.S.A. – Call toll-free 800-227-4224 Outside the U.S.A. – Contact the HACH office or distributor serving you. On the Worldwide Web – www.hach.com; E-mail –
[email protected]
© Hach Company, 2007. All rights reserved. Printed in the U.S.A.
HACH COMPANY WORLD HEADQUARTERS Telephone: (970) 669-3050 FAX: (970) 669-2932
Updated February 2008, Edition 5
