Magnetic Nanophases of Iron Oxide Embedded in Polymer. Effects of Magneto-hydrodynamic Treatment of Pure and Wastewater

摘要

Noticeable effects over some characteristics of pure water such as pH and conductivity were observed after a magneto-hydrodynamic treatment with nanophases of ferromagnetic γ-Fe_2O_3 embedded in a granulated polymer. Unexpected alterations on pH (6,2-10,9) and conductivity (0,06 -0,4) of pure water (de-ionized and bi-distilled) were observed after the first cycle of treatment with more aged (24 h) sample of magnetic nanophases. On the subsequent cycles those values were stabilized and persistent 24 h later. Some specie of memory effect does appear be present 24 h later on a sample of treated water because both pH and conductivity get back slowly to near values to the originals after cycling trough column. In addition an increment on corrosive power was observed via linear variation voltammetry over a piece of carbon steel immersed under a sample of magnetically treated water. The former memory effect was noted too in voltammetry experiments. For lasting a bactericide effect was proved for passing an infected wastewater with fecal coliforms trough a column packed with magnetic nanophases embedded in granulated polymer. A difference on behavior was observed between two samples of magnetic nanophases with different time of age run out in parallel experiments with infected wastewater. The sample with age of 24 h, depleted out roughly two logarithmic units of cell/100 mL of coliforms in a few minutes. On the contrary the sample with 1 h aged didn't remove any coliform in equal time from infected wastewater. The experience was applied at major scale with similar results in experiments run out on 1 m~3 of re-infected wastewater taken from an inside city river during more than 500 hour of operations over an in-serial battery of three interconnected columns loaded with 200 mL of granulated polymer with ferromagnetic nanophases embedded in polymer each one.