In one of my process, I am ending up with one by product that is mixed acid containing 10% HF, 10% HCl and rest water.
I am not sure how to recover value from this. it is not salable in market. Separation via distillation on commercial scale is not economical due to low temperature condensing utility requirement at top. MOC selection for equipment in distillation is also a challenge.
One easiest way to neutralize with any base like NaOH and send to effluent treatment plant (ETP) but I am counting this as last resort as it doesn't recover any value from solution.
Any suggestion or idea from any one?
Hello Girijesh,
One thought is that it should be possible to react the mixed acids (HCL/HF) with a powdered 'white' limestone slurry - agitation and a degree of milling might be necessary. This should give a reaction product of mainly insoluble Calcium Fluoride, which would then need washing to remove water soluble materials (mainly Calcium Chloride), followed by drying. pH would need measuring during the reaction phase to determine end point.
The Calcium Fluoride (*Fluorspar powder) produced, might be a (although relatively low value) saleable product to fluoride 'Flux' manufacturing operations.This would also immobilise the HF content, for safer disposal of residues.
Regards
Al
Cf.:
D.S. Rosenberg, E.A. Belmore (Hooker Chemical Corp.), "Purification of hydrogen chloride", US Patent 3,260,059, July 12, 1966.
M.C. Sze, J.E. Paustian (The Lummus Comp.), "Separation of hydrogen fluoride from hydrogen chloride gas", US Patent 4,009,214, Feb. 22, 1977.
Thanks Al Holmes Carlos Araújo Queiroz
I am planning some R&D trails based on your valuable input