User manual HANNA INSTRUMENTS HI 3857

[. . . ] 2- Replace the cap and shake gently for at least 2 minutes. Note: The ion exchange resin contained in the Demineralizer Bottle is provided with an indicator substance. The indicator will change from green to blue when the resin has been exhausted and has to be replaced with a new one. [. . . ] The solution will 5 mL turn a light blue color. 7- Using the 3 mL plastic pipette, add exactly 5 mL of Chloroform. The chloroform will sink to the bottom of the vial because it is heavier than water. 8- Cap the vial tight and mix by inverting it slowly for 30 seconds. Let it stand for about 1 minute until the chloroform layer separates from the aqueous layer. The color of the aqueous layer will fade slightly, while the chloroform layer turns slightly blue. 9- Using the long plastic pipette, remove the upper aqueous layer and dispose of it. Do not remove the lower chloroform layer too! CHEMICAL REACTION The aqueous solution containing the detergents is treated with the colored indicator. The reaction product can be extracted in the chloroform layer, whilst the original dyestuff is insoluble in the organic medium. The intensity of the color developed is proportional to the concentration of the detergents present. 10-Open the upper part of the Demineralizer Bottle cap and, squirting gently, add to the vial 20 mL of demineralized water, up to the 25 mL mark. 4- Fill the other glass vial with 20 mL of the sample, up to the mark. PRINTED IN ITALY 20 mL 11- Add 2 drops of HI 3857A-0 reagent. ISTR3857 5- Add 2 drops of HI 3857A-0 Detergents Reagent. Replace the cap and swirl to mix. 11/99 12- Cap the vial tight and mix by inverting slowly for 30 seconds. Let it stand for at least 1 minute - until the aqueous layer is unclouded- to allow the chloroform layer to separate from the aqueous layer, as described above. Then, using the long pipette, remove the upper aqueous layer and dispose of it. 13- Repeat from step 10 to 12. The colored chloroform layer is the reacted sample. 14- Insert the reacted sample into the right hand opening of the checker disc. 15- Hold the checker disc so that a light source illuminates the samples from the back windows. plastic pipette, add to the vial 1 mL of sample. [. . . ] Caution: Ultraviolet radiation may cause fading of colors. When not in use, keep the disc protected from light, in a cool and dry place. 16-Rotate the disc while looking at the color test windows and stop when you find the color match. Read the value in the result window and record it in mg/L (or ppm) of Detergents (LAS and/or ABS). REFERENCES Standard Methods for the Examination of Water and Wastewater, 18th edition, 1992 HEALTH AND SAFETY The chemicals contained in this kit may be hazardous if improperly handled. [. . . ]