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 (4L)

Sodium Citrate 112g

Sodium Hydroxide 4 g

Nanopure Water 4L

Brij 35 (30%) 20 ml

Partially fill a 4L Erlenmeyer flask with nanopure water. Add dry chemicals, stir until dissolved then bring to volume (4L) with nanopure water. Filter reagent then add 20 ml 30% Brij 35 (5 ml / L). This may be stored at room temperature or be refrigerated.

Alkaline Phenol (1L)

Sodium Hydroxide (10N or 40% w/v) 80 ml

Liquid Phenol (88%) 94 ml

Nanopure Water 1 L

Partially fill a 1L volumetric flask with nanopure water. Place in ice bath and stir while slowly adding sodium hydroxide first, then liquid phenol. Dilute to volume (1 L) with nanopure water and filter. Store refrigerated in light resistant container.

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 1L volumetric flask with nanopure water. Carefully measure sodium nitroferricyanide and add to nanopure water. Dilute to volume (1L) with nanopure water and filter. Store refrigerated in light resistant container.

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.

10N Sodium Hydroxide (1L)

Sodium Hydroxide 400g

Nanopure Water 1L

Partially fill a 1L volumetric flask with nanopure water and place in ice bath. SLOWLY add sodium hydroxide while stirring to dissolve. This produces an exothermic reaction. Allow solution to cool to room temperature and bring to volume (1L) with nanopure water.

NOTE: This is REALLY messy, nasty stuff to work with so my advice is to buy it already made up.

Nitrate/Nitrite Reagents

Ammonium Chloride EDTA Buffer (4L)

Ammonium Chloride 340 g

EDTA 0.4 g

10N Sodium Hydroxide 26+ ml

Nanopure Water 4L

Brij 35 (30%) 8ml

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 26 ml and add from there as needed) to pH 8.50. Dilute to volume (4 L) with nanopure water and filter. Add 8 ml 30% Brij 35 (2 ml / L). Store refrigerated.

NOTE: Keep some of the buffer on hand that does not have Brij 35 added to it. The buffer without Brij is needed to rinse and store the cadmium reduction coil after use. Routinely 1L of the ammonium chloride EDTA buffer is set aside in a separate 1L bottle and 6 ml of Brij 35 is added to the other 3L. Brij can always be added previous to use if necessary but the cadmium coil should not be stored in buffer that has Brij in it.

Color Reagent (1L)

Phosphoric Acid (85%) 100 ml

Sulfanilamide 40 g

N-1-Naphthylethylenediamine dihydrochloride 2g

Nanopure Water 1 L

Brij 35 (30%) 2 ml

Partially fill a 1 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 (1L) with nanopure water and filter. Add 2ml (2 ml / L) of 30% Brij 35. Store refrigerated in light resistant container.

Cadmium Coil Reactivation Reagents

(see page 16 of The Flow Solution Nitrate/Nitrite Methodology)

Note: DO NOT use HCl acid every time you recharge. This causes excessive damage to the coil. Use only when recharging without HCl is no longer effective.

Nanopure Water

0.5 N Hydrochloric Acid

2% Copper Sulfate

Ammonium Chloride EDTA Buffer (no Brij 35)

0.5 N Hydrochloric Acid (100 ml)

Hydrochloric Acid (conc.) 4.15 ml

Nanopure Water 95.85 ml

Partially fill a 100 ml volumetric flask with nanopure water. While stirring (and in the hood), slowly add the hydrochloric acid. Bring to volume (1L) with nanopure water.

2% Copper Sulfate

Copper Sulfate 20 g

Nanopure Water 1L

Partially fill a 1L volumetric flask with nanopure water. Add copper sulfate and stir until dissolved. Bring to volume (1L) with nanopure water.

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.