Hanna Instruments HI 83208 User Manual
Page 63

63
Silica
SILICA
SPECIFICATIONS
Range
0.00 to 2.00 mg/L
Resolution
0.01 mg/L
Accuracy
±0.03 mg/L ±3% of reading at 25 °C
Typical EMC
±0.01 mg/L
Deviation
Light Source
Tungsten lamp with narrow band interference filter @ 610 nm
Method
Adaptation of the
ASTM Manual of Water and Environmental Technology, D859,
Heteropoly Blue method. The reaction between silica and reagents causes a blue tint in
the sample.
REQUIRED REAGENTS
Code
Description
Quantity
HI 93705A-0
Molybdate
6 drops
HI 93705B-0
Citric acid
1 packet
HI 93705C-0
Amino acid
1 packet
REAGENT SETS
HI 93705-01 Reagents for 100 tests
HI 93705-03 Reagents for 300 tests
For other accessories see page 73.
MEASUREMENT PROCEDURE
• Select the
Silica method using the procedure described in
the
Method Selection section (see page 12).
• Fill the cuvette with 10 mL of unreacted sample (up to the
mark).
• Add 6 drops of HI 93705A-0 Molybdate reagent. Replace
the cap and swirl the solution.
• Wait for 4 minutes, add the content of one packet of
HI 93705B-0 Citric acid reagent and shake until it is
completely dissolved.
• Wait for 1 minute. This is the blank.
10 mL