Iron filings surface modifier and method for preparing alpha-Fe<(1-x)>Cr<x>OOH active layer

Abstract

The invention relates to an iron filings surface modifier and a method for preparing an alpha-Fe<(1-x)>Cr<x>OOH active layer. The surface modifier comprises the following components in percentage by mass: 30-50% of polyethylene butyral resin, 3-10% of chromium sulfate, 3-10% of ferric oxide, 0.2-2% of sodium phosphate, 0.5-5% of sodium dodecylsulfonate, and the balance water. The modification is performed by the following steps: (1) performing degreasing cleaning on waste iron filings; (2) performing surface modification in the iron filings surface modifier; and (3) cleanly rinsing the surfacewith water after the surface modification is completed, and then performing natural air-drying. Compared with the prior art, the method uses iron filings as a raw material, and the surface of the iron filings is modified by an appropriate chemical method, so that surface components of the iron filings have catalytic ozone activity, and a dense structure to protect the iron filings matrix, the total iron content in outlet water is reduced, the catalyst's dissolution loss is inhibited, and thereby the method is a feasible way to reduce the catalyst cost of an advanced oxidation method and improve the outlet water quality, and has important practical value.

Description

technical field [0001] The invention relates to the field of water pollution control, in particular to a surface modifier for iron filings and preparation of α-Fe (1-x) Cr x OOH active layer method. Background technique [0002] Ozone has a history in water pollution control. Ozone has a strong oxidizing property (redox potential of 2.07V) and a special dipole structure. It has a good oxidation effect on organic compounds with rich electron groups, such as phenol, amine and olefin. At present, it is generally believed that there are two reaction pathways for the reaction of ozone with organic matter in water: one is the direct reaction with ozone molecules, and the other is the free radical reaction that generates OH when ozone is decomposed. The former mainly converts pollutants into other organic matter, while the latter can achieve better mineralization efficiency, because OH (oxidation-reduction potential 2.33V) can react with most compounds in water without selection...

AI Technical Summary

Problems solved by technology

[0005] During use, although iron oxides with catalytic ozone activity are formed on the surface of iron filings, the adhesion of the surface substances is poor, and it is easy to flow out with iron mud along with the effluent

In addition, due to the poor protection of the surface iron oxides on zero-valent iron, especially when the content of chloride ions in the sewage is large, it is more difficult to form stable surface iron oxides, and the zero-valent iron gradually dissolves with the increase of use time. Increased catalyst consumption

Furthermore, the content of Fe(III) in the water is high, and it is necessary to increase the follow-up treatment process to remove the sediment colloid, which increases the processing unit

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