LaMotte DC1600 Colorimeter - Manual (Page 55)

MOLYBDENUM
THIOGLYCOLATE METHOD CODE 3699-01
QUANTITY CONTENTS CODE
60 mL *Mo Buffer *3997-H
60 mL *Molybdenum Oxidizing Reagent *6485-H
2.5g *Molybdenum Indicator Powder 6486-S
1 Spoon, 0.05g, plastic 0696
2 Pipets, 1.0 mL, plastic, w/caps 0372
*WARNING: Reagents marked with a * are considered hazardous substances. Material Safety Data Sheets (MSDS) are supplied for
these reagents. For your safety read label and accompanying MSDS before using.
Molybdenum occurs naturally in the earth’s crust as molybdenite and wolfenite, and is an important element in many
biochemical reactions, including nitrogen fixation. In industrial processes, such as the operation of boilers and cooling
towers, molybdenum, in the form of sodium molybdate, is used as an environmentally safe corrosion inhibitor.
APPLICATIONS: Boiler and cooling water
RANGE: 0 – 50 ppm Molybdenum
METHOD: Calcium thioglycolate reacts with molybdenum to give a yellow color with an intensity
proportional to the amount of molybdenum present.
SAMPLE HANDLING
& PRESERVATION: Molybdenum samples may be stored in either plastic or glass containers.
INTERFERENCES: Nickel levels less than 50 ppm do not interfere; aluminum levels less than 10 ppm do not
interfere; chromate at higher concentrations interferes due to the intense yellow color. Ferrous
iron levels below 50 ppm do not interfere, but low levels of ferric iron will cause a large blank.
Highly buffered samples may exceed the capacity of the system possibly producing inaccurate
results.
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