2255000 Silica Test Kit, Model SI-7

Model SI-7 is used for silica measurement in the range of 0 - 1 mg/L SiO₂ in water samples by color disc/Heteropoly Blue Amino Acid method. Silica Test Set can be used to conduct 100 silica tests with the smallest increment of 0.05 mg/L SiO₂.

Silica Test Set includes:

• Amino Acid F Reagent Powder Pillows (p/n 2253869)
• Citric Acid F Reagent Solution (p/n 2254232)
• Molybdate 3 Reagent Solution (p/n 199532)
• 29 mL Square Bottle, with 10, 15, 20 and 23-mL marks (p/n 232706)
• Silica Color Disc, 0-1 mg/L (p/n 9266800)
• Color Comparator Box (p/n 173200)
• 18 mm Glass Viewing Tubes (p/n 173006)
• Long-path Adapter (p/n 2412200)
• Stoppers for 18-mm Glass Tubes and AccuVac Ampuls (p/n 173106)

Procedure for SiO₂ analysis

Before you start take into account the following:

• Use sunlight or lamp as the source of light to find the matching color with the color comparator box.
• Pull apart the flat plastic sides, open the color disc, remove the thin inner disc and dry all parts with a soft cloth if the color disc is wet.
• Use the standard solution as the sample to control the test accuracy.
• The reaction times in the test procedure are for samples at 20 °C. If the sample temperature differs, refer to the instructions for the appropriate reaction time.

Test procedure

Insert the long-path adapter in the color comparator box. Pour the collected sample up to the top line of the first tube. Install the tube into the left opening of the color comparator box. Mix 20 mL of sample and 0.5 mL Molybdate 3 Reagent Solution in the bottle. After 4 minutes, the yellow color appears if the sample contains silica or phosphate. Pipet 0.5 mL Citric Acid F Reagent Solution and swirl the content of the bottle, after one minute the interference from phosphate will be removed. Add Amino Acid F Reagent Powder Pillow and swirl to mix. The blue color develops if the silica is present in the sample. Transfer the pretreated sample up to the top line of the second tube. Insert the second tube into the color comparator box. While holding the color comparator box under the light source, turn the disk to find a color match. Check the results in mg/L in the scale window.