what is the % purity of nitrogen required in manufacturing?
99.998
Perecent purity of Nitrogen gas depends upon its application in the manufacturing.
If it is used as a"Blanketing medium" during manufacturing of APIs or finished pharmaceuticals which are susceptible for air oxidation, in such cases Nitrogen used must have impurity of Oxygen as minimum as possible. Therefore, depending upon its usage in the manufacturing operations, impurities of Oxygen, Carbon dioxide, Carbon monoxide, SO2 etc should be controlled.
Please refer different pharmacopoeia-, IP, USP, BP to understand the requirements.
High-purity grades of nitrogen are composed of greater than 99.998 percent nitrogen. The common high-purity grade names include Research Purity and Ultra High Purity. All of the high-purity grades can also be considered Zero grade. This is because they meet the specification of having less than 0.5 parts per million of total hydrocarbons required of Zero grade nitrogen. Besides hydrocarbons, nitrogen contains other impurities like oxygen, carbon dioxide, carbon monoxide and water. None of the high-purity grades contain oxygen greater than 0.5 parts per million, carbon dioxide or carbon monoxide greater than one part per million, or water greater than three parts per million.
The pharmaceutical industry uses high-purity grades as a shield gas for some medications. The high-purity nitrogen protects the medicine from contacting and reacting with surrounding oxygen and moisture because it is a non-reactive gas, especially if it contains low levels of impurities.