摘要
The effects of Fe0 pre-corrosion by water,bicarbonate,chloride,phosphate and sulfate on the efficiency of Fe0 systems for water treatment were investigated.Batch experiments were conducted for a total duration of 72 days with MB(Methylene Blue)and MO(Methyl Orange).The efficiency of used Fe0 was assessed by characterizing the extent of MB and MO discoloration,pH variation and amount of iron released as a function of anion type.Before dye addition,used Fe0 in Fe0/sand and 100%Fe0 systems was allowed to equilibrate with H2O or the anionic solution for 0 to 44 days.Pre-corrosion has low impact on MB discoloration but has negative impact on MO discoloration.Relative to the reference system(anion free system,H2O),all the tested anions enhanced MB discoloration but decreased that of MO.HPO4 2-and HCO3-severely affects MO discoloration.The pH of the medium governs the discoloration with MB performing better at higher pH and MO doing same at lower pH.For MB,Fe0/sand system shows higher efficiency than 100%Fe0 system.But the two systems show similar efficiency for MO.Results will help in the design and functioning of Fe0 based filtration systems and other water treatment designs using Fe0.
