Whch one of the following substances is used to reactivate the de activated filters in activated carbon method for defluoridation ?

Whch one of the following substances is used to reactivate the de acti

1.	Whch one of the following substances is used to reactivate the de activated filters in activated carbon method for defluoridation ?
Answer» Defluoron -I `CaCOCl_(2)`, lime and ALUM 4% NAOH solution and then 1% `H_(3) PO_(4)` solution 4% NaCI solution and then 5% `H_(2) SO_(4)` solution. Answer :C