Hello,
I am a purchasing consultant in the UK and one of my clients uses 20% Nitirc Acid in a process called Shaped Tube Electrolytic Machining
A negative charge is applied to Titanium tubes while a positive charge is applied to the work piece. The acid becomes the electrically conductive fluid.
The acid is actually comtaminated with nitrates on receipt to aid the process.
During operation the acid becomes contaminated with dissolved metals such as Molybdenum, Niobium, Nickel and Tungsten.
I am currently looking in to the possibility of using diffusion dialysis to recover and extend the life of the acid but the investment is high.
One of my client's employees saw a process at a company in the US that in simple terms evaporated the acid solution away from the disolved metals and I am interested to know if this is feasible, the equipment that would be needed and if any organisation could help with a trial experiement.