Preparation Of Microwave Induced Sensitizer And It’s Application In Coking Wastewater

Microwave-induced oxidation process (MIOP) is a kind of water treatment methoddeveloped in recent years which can be used to oxidate or degradate organic matter at normaltemperatures and pressures. MIOP can degradate refractory wastewater effectively and steadily.Coking wastewater contains lots of refractory substance which can hardly be dispoed by normalmethods. This research prepared the composite metal sensitizer and applied it to the treatment ofcoking wastewater combined with lfocculation-microwave induced oxidation process.In this paper,microwave-induced composite sensitizer CuO/A100H(pseudo-boehmite) waspreparated by rfactional precipitation method.The effect of aluminium chloirde and coppernitrate mole ratio, roasting temperature and roasting time on the sensitizer activity wereinspected.Surface of sensitizer structure,composition and morphology were analysed throughSEM，XRD and IR.The best preparation conditions were determined: aluminium chloride andcopper nitrate mole ratio was2:1，roasting temperature350。C and roasting time3h.Flocculating was used to treat coking wastewater before biochemical.The lfocculation effectof coking wastewater by polyaluminium chloirde and polymeric ferric sulfate was inspected.Theresults showed: polymeric ferric sulfate on CODcr,chroma,TOC removal effects are better thanthat of polyaluminium chloride. Polymeric ferric sulfate was selected as the flocculant incombined process.Coking wastewater before biochemical was treated by lfocculation-microwave inducedoxidation process integration,and the stability of this integration process was also tested. Whendosage of PFS was1600mg/L, dosage of sensitizer was lOg^L，microwave power was900W,irradiation time was6min，the effects of chroma,TOC,CODcr removal have good stability,chroma between30-70,TOC between50-70mg/L,CODcr between70-100mg/L.The effluentreached the direct emission standard according the “emission standard of pollutants for cokingchemical industry"(GB16171-2012).Coking wastewater atfer biochemical was also treated by microwave-induced oxidationprocess. Under the optimum processing conditions: chroma removal rates was93.1%,theremaining CODcr was64mg/L“,reached the direct emission standard according theemissionstandard of pollutants for coking chemical industry”(GB16171-2012).