Alpkem Recipes

Follow all lab safety protocols when handling chemicals, including protective eye and skin wear and appropriate lab clothing.

Ammonium Reagents

Citrate Complexing Reagent (2L)

Sodium Citrate 63g

Sodium Hydroxide Pellets 2g

Nanopure Water

Brij 35 (30%)

Partially fill a 2.0 L volumetric flask with nanopure water. Add dry chemicals, stir until dissolved then bring to volume with nanopure water. Filter reagent and store in refrigerator for up to 6 weeks. To prepare working reagent add 5 ml of Brij / L of solution. Prepare working reagent fresh daily.

Alkaline Phenol (.5L)

Sodium Hydroxide (10N or 40% w/v) 40 ml

Liquid Phenol (88%) 47 ml

Nanopure Water

Partially fill a 500 ml volumetric flask with nanopure water. Place in ice bath and stir while slowly adding sodium hydroxide first, then liquid phenol. Dilute to volume with nanopure water and filter. Store refrigerated in light resistant container. This reagent should be made as needed and not stored more than 3 days.

NOTE: This reagent is hazardous waste! Any glassware, paper towels, gloves, filter paper, etc used/contaminated during this process must be treated or disposed of as hazardous waste.

Sodium Nitroferricyanide (1L)

Sodium Nitroferricyanide 0.5 g

Nanopure Water 1L

Partially fill a 1.0 L volumetric flask with nanopure water. Carefully measure sodium nitroferricyanide and add to nanopure water. Dilute to volume with nanopure water and filter. Store refrigerated in light resistant container for up to 6 weeks.

NOTE: This reagent is hazardous waste! Any glassware, paper towels, gloves, filter paper, etc used/contaminated during this process must be treated or disposed of as hazardous waste.

Nitrate/Nitrite Reagents

Ammonium Chloride EDTA Buffer (4L)

Ammonium Chloride 340 g

EDTA 0.4 g

10N Sodium Hydroxide 20+ ml

Nanopure Water

Brij 35 (30%)

Partially fill a 4L Erlenmeyer flask with nanopure water. Add ammonium chloride and EDTA and stir until dissolved. Adjust buffer solution using 10 N sodium hydroxide (start with 20 ml and add from there as needed) to pH 8.50. Dilute to volume (4 L) with nanopure water and filter. Store refrigerated. To prepare working reagent add 4 ml Brij 35 / Liter of solution. Prepare working reagent fresh daily.

NOTE: Always keep some buffer available that does not have Brij 35 added. This is used when reactivating the cadmium reduction coil.

Color Reagent (1L)

Phosphoric Acid (85%) 100 ml

Sulfanilamide 40 g

N-1-Naphthylethylenediamine dihydrochloride 2g

Nanopure Water

Brij 35 (30%) 2 ml

Partially fill a 1.0 L volumetric flask with nanopure water. On stir plate, add phosphoric acid then dry chemicals. Stir until dry chemicals are dissolved. This can take several hours of stirring. Bring to volume with nanopure water and filter. Store refrigerated in light resistant container for up to 8 weeks.

Cadmium Coil Reactivation Reagents

(see page 17 of The Flow Solution Nitrate/Nitrite Methodology)

0.5 N Hydrochloric Acid (100 ml)

Hydrochloric Acid (conc.) 4.9 ml

Nanopure Water

Partially fill a 100 ml volumetric flask with nanopure water. While stirring (and in the hood), slowly add the hydrochloric acid. Bring to volume with nanopure water.

2% Copper Sulfate

Copper Sulfate 2 g

Nanopure Water

Partially fill a 100 ml volumetric flask with nanopure water. Add copper sulfate and stir until dissolved. Bring to volume with nanopure water.

Also required for Nanopure water and Ammonium Chloride EDTA reagent (NO brij added) are also required for coil reactivation.

1000 ppm Stock Standards

1000 ppm Nitrogen as Ammonium (NH4-N) (1L)

Potassium Nitrate (dried at 110 degrees C) 4.7168 g

Nanopure Water 1L

Dry about 6-7 g ammonium sulfate in oven at 110 degrees C for a minimum of two hours. Weigh out 4.7168 g of dried ammonium sulfate and add to a partially filled 1L volumetric flask. Dissolve and dilute to volume with nanopure water. Refrigerate when not in use.

1000 ppm Nitrogen as Nitrate (NO3-N) (1L)

Potassium Nitrate (dried at 110 degrees C) 7.2180 g

Nanopure Water 1L

Dry about 10 g ammonium sulfate in oven at 110 degrees C for a minimum of two hours. Weigh out 7.2180 g of dried potassium nitrate and add to a partially filled 1L volumetric flask. Dissolve and dilute to volume with nanopure water. Refrigerate when not in use.

1000 ppm Nitrogen as Nitrite (NO2-N) (1L)

Potassium Nitrite (dried at 110 degrees C) 6.0720 g OR Sodium Nitrite (dried at 110 degrees C) 4.9260 g

Nanopure Water 1L

Dry about 8-10 g of potassium or sodium nitrite in oven at 110 degrees C for a minimum of two hours. Weigh out 6.0720 g of dried potassium nitrite OR 4.9260g sodium nitrite and add to a partially filled 1L volumetric flask. Dissolve and dilute to volume with nanopure water. Refrigerate when not in use.

Super Cartridge Cleaning Solutions

If there are problems with contamination in the cartridges the following solutions may be used to clean the interior and related tubing. It is not necessary to disconnect plumbing to do this.

Nitrate/Nitrite Cartridge

1N Sodium Hydroxide

1 N Hydrochloric Acid

Ammonium Cartridge

1N Sodium Hydroxide

1 N Sulfuric Acid

1 N Sodium Hydroxide (500 ml)

10 N Sodium Hydroxide 50 ml

Nanopure Water 450 ml

Partially fill a 500 ml volumetric flask with nanopure water. While stirring (and in the hood), slowly add the sodium hydroxide. Bring to volume (500 ml) with nanopure water.

1 N Hydrochloric Acid (200 ml)

Hydrochloric Acid (conc.) 16.6 ml

Nanopure Water 183.4 ml

Partially fill a 200 ml volumetric flask with nanopure water. While stirring (and in the hood), slowly add the hydrochloric acid. Bring to volume (200 ml) with nanopure water.

1 N Sulfuric Acid (200 ml)

Sulfuric Acid (conc.) 5.5 ml

Nanopure Water 195.5ml

Partially fill a 200 ml volumetric flask with nanopure water. While stirring (and in the hood), slowly add the sulfuric acid. Bring to volume (200 ml) with nanopure water.