Acid recovery of aluminum foil pickling process
The electrolytic capacitor is one of the most utilized electronic components in modern electronic devices, and the global market for electrolytic capacitors has grown steadily. Chemosynthesis aluminum anode foil is the most important and valuable part in these capacitors. To produce aluminum anode foil, fresh acids (typically HCl, H2SO4, HNO3 or various mixtures of them) are used to etch the smooth aluminum foil surfaces, and consequently large amount of waste acids, which contain the remaining free acids and soluble aluminum species, are produced.
Bipolar Electrodialysis (EDBM) can convert the salt into corresponding acid and base for reuse as process electrolytes to realize total recovery of free acids and prevent generation of highly polluting effluents.