Preparation of Cellular Iron Using Wastes and its Application in Dyeing Wastewater Treatment

Cellular iron (porous iron) was prepared using a mixture of iron filings (waste from machinery industry) or pure iron powder with sawdust (waste from wood industry) and Bisphenol A epoxy resin, heated at 700–750∘C. The porosity of cellular iron increased with the amount of sawdust serving as space-holding filler in the mixture. Carbon oxide gases as burning products of sawdust formed a reducing furnace atmosphere and created additional pores in the iron matrix. When the ratio of iron filings to sawdust was 2:1, the porosity of cellular iron was up to 80%. Batch and column experiments of treating dyeing wastewaters with cellular iron indicate that the decolorization process, a quasi-first order reaction, was pH-dependent. Under acidic conditions, the color removal efficiency using cellular iron was up to 75–80% and three times faster than that using iron filings. The proposed technology has great potential for use in cellular iron mass production and wastewater treatment.