SACRIFICIAL ANODES CATALYZING ELECTRO-FENTON OXIDATION OF WASTEWATER

Technologies which are based on electro-Fenton processes could be considered as a modern and effective way in wastewater treatment. Commonly used catalysts of Fenton oxidation are ions of Fe2+. New and modern catalyst found more use as selective agents for specific pollutants yet Catalyst in form of Fe2+ is meeting important attributes and could be suitable dosage by electrochemical dissolving of sacrificial steel anode. It was comparison between two material types of sacrificial anode - Steel 17 240 Cr-Ni (DIN X 5 CrNi 18 10, AISI 304) and Steel 11 373 (DIN USt 37-2). Both steels are common commercially available products with excellent stable quality and reasonable price, which are produced in the Czech Republic. It is necessary to take into account the specific properties of both materials under conditions of electro-Fenton process. The main influence of pH range 2-4 in which experiments were processed. Steel 17 240 Cr-Ni (DIN X 5 CrNi 18 10, AISI 304) has a lower corrosion losses under the same conditions. Non-alloy steel 11 373 (DIN USt 37-2) has enough corrosion rate to dose to electro-Fenton process necessary amount of catalytic Fe2+ ions dependence of surface and current density. The usage of alloy steel 17 240 Cr-Ni is materially five times more expensive. It is necessary to connect power supply to increase small corrosion rates. Ferrous and ferric sludge which are in water could be effectively precipitated by neutralization purified water and removed by sedimentation. Residual concentration of total iron 0,37 mg center dot l(-1) mets the conditions in Government Regulation No. 61/2003 Coll., about values of pollution by iron in the surface and wastewaters, where is a limit for iron 0,55 mg center dot l(-1).