Abstract
Purification of crude phosphoric acid manufactured by the wet process from toxic heavy metals such as Iron, zinc, and Manganese is considered to be a very significant environmental and economical procedure. For studying the purification of phosphoric acid, a synthetic solution of 100 ppm from Iron (III), Zinc (II), and Manganese (II) was prepared. The present work aimed to remove Iron (III), Zinc(II), and Manganese(II) from the synthetic liquor by Polyurethane foam (PU) and Charcoal (C) impregnated with di-(2-ethylhexyl) phosphoric acid (D2EHPA) to purify the solution and find out which impregnated sorbent material introduces the best adsorption characters for the presented heavy metals. The results showed that the % Impregnation D2EHPA on C is the highest which equals 56.97% under optimal conditions of impregnation D2EHPA with C and the maximum adsorption capacity was at D2EHPA's concentration of 0.23 Mol/L at contact time 5 hrs, m/v ratio 6g/L and using Benzene as diluents in room temperature. By applying the SIR to remove Iron (III), Zinc(II), and Manganese(II) from a 100 ppm synthetic solution, the results showed that the preferred parameters are pH 3 for Fe, pH 6 for Zn, pH 7 for Mn, time 3h., m/v ratio = 0.05gm/10ml at room temperature. The SIR was effective in removing heavy metals from crude phosphoric acid.