Missouri State University

Waste Neutralization Guidance

Hazardous waste regulations allow elementary neutralization (treatment) of hazardous waste without a permit if it is hazardous only because it exhibits the characteristic of corrosivity. Appropriate personal protective equipment must be worn and the activity must take place under a vent hood using accepted neutralization procedures and chemicals to prevent a violent reaction. Knowledge of the chemical constituents in the waste is imperative. For safety reasons, no wastes should be neutralized or mixed together without prior knowledge of the make-up of the substance.
The neutralization must take place in the accumulation container and the container must be in compliance with the regulations regarding management of containers, i.e., the container must be labeled, the beginning date of accumulation must be provided, and the container must be kept closed except when adding or removing the waste. For this reason, it is important that elementary neutralization of the waste take place before the container is ¾ full to allow for the addition of the neutralizing agent and prevent pressurization of the container.
Once the pH has been adjusted to between 2 and 12.5, it is no longer a "hazardous waste" and, if necessary, it can be transferred to a different container for further neutralization. The pH must be between 5 and 12.5 for it to be disposed of into the sanitary sewerage system. Once it is adjusted to an acceptable pH, the waste can be poured down the drain and flushed with an equal amount of water. The amount and type of waste must be recorded and reported to the Director of Environmental Management.
Following is a list of commonly generated waste streams that can be neutralized and disposed of into the sanitary sewers:
  • Copper sulfate/Nitric acid
  • Copper nitrate, copper sulfate, copper acetate, and copper chloride/acid
  • Hydrochloric acid/Thiamine/Pyroxidine
  • Nitric acid/Copper nitrate/Potassium nitrate/Sodium nitrate
  • Sodium bicarbonate
  • Ammonium hydroxide/nitric Acid mix

Protective Equipment

to be worn includes:
  • Face Shield
  • Nitrile Gloves
  • Acid resistant apron