Purification and utilisation of iron-contaminated sulphuric acid

The purification and utilisation of sulphuric acid contaminated with iron is discussed in detail. It is found that treatment of the acid with FeSO₄·7H₂O resulted in complete removal of the iron impurity. Partial removal of the iron was affected by treatment with acetone and ammonium sulphate. Treatment with activated carbon was not found to be effective. The study shows that the contaminated sulphuric acid can be utilised to prepare sodium sulphate and calcium sulphate.