When concentrated Sulfuric Acid and water are mixed, a tremendous amount of heat is released due to ionization of the acid. For instance, adding 1 volume of concentrated Sulfuric Acid to an equal volume of water (both at 25°C) results in a temperature rise to over 135°C. Therefore, the acid should always be diluted by adding it to the water. If the water is added to the acid, spattering could result which creates a hazardous situation and the possibility for severe chemical burns. The use of a 1 + 1 dilution of Sulfuric Acid with water (50% Sulfuric Acid, Group No. 8180) offers a much safer alternative in many instances when the use of Sulfuric Acid is required. For example, when 1 volume of concentrated Sulfuric Acid is added to 3 volumes of water, the temperature rises from 25°C to over 90°C. When the same solution is made by diluting 1 volume of 50% Sulfuric Acid with 1 volume of water, the temperature rises to less than 50°C.

The most common oxygen scavengers in oilfield production are sodium bisulfite (SBS) and ammonium bisulfite (ABS). Ammonium bisulfite is more water soluble than sodium bisulfite and typically react with oxygen faster. However, ammonium in the ammonium bisulfite can promote bacteria growth.

Being a salt of a weak acid and a strong base, sodium bisulfite forms a significantly basic aqueous solution whereas ammonium bisulfite is only slightly basic at around pH 8. As a rule of thumb, 60ppm of 65wt% ammonium bisulfite is required to reduce the oxygen concentration in water from 9ppm to 50ppb.

The reaction of bisulfite with oxygen is typically faster at higher temperatures and can be facilitated by transition metal ion catalysts, e.g. Cobalt.

The most common applications of oxygen scavenger in oil and gas production are for seawater injection facilities, hydro-testing, and acid stimulation

It is used to arrest oxygen in sea water

It removes Entrapped Oxygen and thus reduces Corrosion

In Oil Drilling Chemicals