Hach AutoCAT 9000, Инструкция по эксплуатации

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Total Chlorine
© Hach Company, 2002–2003, 2007. All rights reserved. Printed in the U.S.A. 3/07 3ed
Page 110
50081_Chlorine_Total_Forward.fm
HACH COMPANY
WORLD HEADQUARTERS
Telephone: (970) 669-3050
FAX: (970) 669-2932
FOR TECHNICAL ASSISTANCE, PRICE INFORMATION AND ORDERING:
Call 800-227-4224
Contact the HACH office or distributor serving you.
www.hach.com techhelp@hach.com
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; E-mail –
toll-free
Safety
Good safety habits and laboratory techniques should be used throughout the procedure.
Consult the Material Safety Data Sheet (MSDS) for information specific to the reagent(s)
used.
Summary of Method
This procedure follows method number 4500-Cl D. in “Standard Methods for the
Examination of Water and Wastewater” (20th Edition). This procedure permits
determination of the total chlorine concentration (
= Free Chlorine Conc. + Combined
Chlorine Conc.
) in a water sample. Total chlorine corresponds to the chlorine derived from
all its possible forms in solution including free elemental chlorine (Cl
2
), hypochlorous
acid (HOCl), hypochlorite (OCl
–
) ion, and chloramines (NH
2
Cl, NHCl
2
, etc.) among
other species.
In the procedure an excess of potassium iodide is added to a water sample. Sample pH is
adjusted to pH 4 by addition of acetate buffer. The sample solution is then titrated
amperometrically with standard phenylarsine oxide solution.
Required Reagents
Description Qty. required per test Unit Cat. No.
Acetate Buffer Solution, pH 4, w/dropper...................................................1 mL................. 100 mL ...............14909-32
Phenylarsine Oxide (PAO) Titrant, 0.00564 N............................................ varies................ 1000 mL ...............1999-53
Potassium Iodide, SwifTest refill ................................................................0.10 g ............... 25 g.......................1077-60
Required Apparatus
Beaker, Glass, 250-mL ................................................................................ 1 ....................... each......................500-46H
Cylinder, Graduated, 250 mL ......................................................................1 ....................... each.........................508-46
Magnetic Stir Bar, Teflon
®*
coated............................................................. 1 ....................... each.....................50085-00
SwifTest dispenser.......................................................................................1 ....................... each.....................28341-00
Optional Reagents
Chlorine Standard Solution, Voluette Ampules........................................... varies................ 16/pkg.................14268-10
Dilution water, organic-free ........................................................................varies................ 500 mL ...............26415-49
Potassium Iodide, Powder Pillows ..............................................................1 ....................... 100/pkg.................1077-99
Sodium Thiosulfate Standard Solution, stabilized, 0.00564 N ...................varies................ 1 L ......................24088-53
Optional Apparatus
Mini-printer, thermal, w/cable............................................................................................... each.....................A70P021
*Teflon is a Registered Trademark of EI DuPont Company.