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  for Metal Finishing since 1989
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Recycle/recover caustic

Currently, we clean off our parts with 100% sodium hydroxide, until the NaOH builds up with solids and metals. We then neutralize the caustic solution prior to disposal. Does anyone know of a method/process/company who can help us recycle/recover the caustic for reuse?

troy pfaff
- Milwaukee, WI
2000

It is difficult to help. 100% sodium hydroxide is a solid, as flakes or pellets. As soon as it absorbs moisture, it is no longer 100%, so what do you really have.

Also no one can help if they have no idea of what dirt and metals are contaminating your cleaner. What is your cutoff point for this contamination.

James Watts
- Navarre, Florida
2000

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2000

I'm making some assumptions:

1. You probably mix the NaOH into water for cleaning.

2. You are probably cleaning steel parts.

3. The solution is heated.

4. You rinse the parts, creating a second contaminated stream.

If that's all close, you probably would be well served by looking into a formulated cleaner made for cleaning whatever part/soil you have. Although it may cost more to buy, it should far outlast what you have now, and save you money on treatment costs.

Jeff Watson
- Pearland, Texas