Method (0.1 to 8.0 mg/l Cu) TNTplus 860

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2 Chlorine, Total, Bulk Powder, 8167 DOC Bathocuproine Method 1 Method (0.1 to 8.0 mg/l Cu) TNTplus 860 Scope and Application: For water, wastewater and process water. Digestion may be required to determine total copper. 1 Adapted from Standard Methods for the Examination of Water and Wastewater. Test preparation How to use instrument-specific information The Instrument-specific information table displays requirements that may vary from instrument to instrument. To use this table, select an instrument then read across to find the corresponding information required to perform this test. Before starting the test: Table 1 Instrument-specific information Instrument Light shield Adapter DR 5000 DR 2800 LZV646 DR 2800 only: Install the light shield in cell compartment #2 before performing this test. Read the safety advice and expiration date on the package. The recommended sample and reagent temperature is 15 to 25 C (59 to 77 F). The recommended sample ph is 2.5 to 11. The recommended reagent storage temperature is 15 to 25 C (59 to 77 F). A sample digestion may be necessary to measure undissolved copper or copper bound in complexes. The digestion can be performed with the Metals Prep Set TNT890 or by the USEPA mild or vigorous digestion procedure. Change the chemical form to "Cu 890" if analyzing a sample that has been digested with the TNT 890 Metals Prep Set. TNTplus methods are activated from the main menu when the sample vial is inserted into the sample cell holder. Collect the following items: Description Quantity TNTplus 860 vials varies Light shield or adapter (Instrument-specific information) 1 Pipette for 2.0 ml sample 1 Pipette tips varies Refer to Consumables and replacement items on page 4 for reorder information. Page 1 of 4

3 Bathocuproine Method, TNTplus Pipet 2.0 ml of sample into the vial. 2. Cap and invert the vial until the contents are well-mixed. 3. Wait 3 minutes. 4. After the timer expires, wipe the sample vial and insert it into the cell holder. The instrument reads the barcode, selects the method and makes the measurement. No zero is necessary. Results are in mg/l Cu. Interferences The ions listed in Interfering substances and levels have been individually tested up to the given concentrations and do not cause interference. The cumulative effects of these ions or the influence of other ions have not been determined. Higher amounts of iron and chromium can cause high-bias results. Undissolved copper contained in complexes can only be determined after digestion. Table 2 Interfering substances and levels Interfering substance Tin (Sn 2+ ), Mercury (Hg 2+ ) Iron (Fe 2+, Fe 3+ ) Chromium (Cr 3+, Cr 6+ ) Zinc (Zn 2+ ), Cadmium (Cd 2+ ), Nickel (Ni 2+ ), Lead (Pb 2+ ) Magnesium (Mg 2+ ), Potassium (K + ), Sodium (Na + ), Ammonium (NH 4 +), Calcium (Ca 2+ ), Phosphate (PO 4 3-), Carbonate (CO 3 2-), Nitrite (NO 2 -) Chloride (Cl - ), Nitrate (NO 3 - ), Sulfate (SO 4 2- ) Interference level 5 mg/l 15 mg/l 25 mg/l 50 mg/l 500 mg/l 1000 mg/l Page 2 of 4

4 Sample collection, preservation and storage Accuracy check 1. Collect samples in acid-cleaned glass or plastic containers. 2. Adjust the ph to 2 or less with concentrated nitric acid (approximately 2 ml per liter). 3. Store preserved samples up to 6 months at room temperature. 4. Before analysis, adjust the ph to 4 to 6 with 8 N potassium hydroxide. Do not exceed ph 6, as copper may precipitate. 5. Correct the test result for volume additions. 6. If only dissolved copper is to be determined, filter the sample before acid addition. Standard solution method Required for accuracy check: standard solution, 100 mg/l Cu Pipette for 4.0 ml volume Pipette tip Volumetric flask, 100 ml Prepare a 4.00 mg/l standard: Pipet 4.0 ml of copper standard solution, 100 mg/l as Cu, into a 100 ml volumetric flask. Dilute to volume with deionized water, stopper and invert to mix. Perform the Bathocuproine Method, TNTplus 860 procedure with this solution. Results should be 4.0 mg/l. Method performance Instrument Summary of method Standard Precision 95%Confidence Limits of Distribution Sensitivity Concentration change per Abs change DR mg/l Cu 3.9 to 4.1 mg/l Cu 0.04 mg/l Cu DR mg/l Cu 3.9 to 4.1 mg/l Cu 0.04 mg/l Cu (I) ions form an orange-colored complex with the disodium salt of bathocuproine disulphonic acid. Any copper (II) ions present in the water sample are reduced to copper (I) ions by ascorbic acid before the complex is formed. Test results are measured at 478 nm. Page 3 of 4

5 Consumables and replacement items Required reagents Description Quantity/Test Unit Catalog number TNT860 reagent set 1 25/pkg TNT860 Required apparatus Description Quantity/Test Unit Catalog number Light shield (DR 2800 only) 1 each LZV646 Pipette, variable volume, 1 to 5 ml 1 each BBP065 Pipette tips, for BBP065 pipette varies 75/pkg BBP068 Recommended standards Description Unit Catalog number standard solution, 100 mg/l 100 ml Optional reagents and apparatus Description Unit Catalog number Bottle, sampling, low density poly, w/cap, 500 ml 12/pkg Nitric acid, ACS 500 ml Potassium hydroxide, 8N 500 ml Metals prep set, TNTplus 50 digestions TNT890 DRB200 reactor, 115V, 9 x 13 mm vial wells, 2 x 20 mm vial wells 1 each DRB Volumetric flask, Class A 100 ml Deionized water 4 L Other configurations are available. Refer to the Web or catalog for details. FOR TECHNICAL ASSISTANCE, PRICE INFORMATION AND ORDERING: In the U.S.A. Call toll-free Outside the U.S.A. Contact the HACH office or distributor serving you. On the Worldwide Web techhelp@hach.com HACH COMPANY WORLD HEADQUARTERS Telephone: (970) FAX: (970) Hach Company, All rights reserved. Printed in the U.S.A. Updated October 2008, Edition 1