Applying the native ore of Inner Mongolia Baiyun as the catalyst(C) and persulfate(PS) as the oxidant
three oxidation systems of C/PS
UV/PS and C/UV/PS were established to treat the bio-treated effluent of coking wastewater. Ultra-filtration and organic matter resin separation were used to analyze the relative molecular weight distribution (MW) and hydrophobicity-hydrophilicity of organic compounds in bio-treated effluent of coking wastewater. The results showed that
there exist more organic compounds of refractory aromatic organic matter and those are mainly organic matter of MW<1×103
the next is such organic matter of MW>100×103 and MW between 10×103-100×103. In the wastewater searched the types of organic matter of hydrophobic-acid fraction and hydrophobic-neotral fraction played a predominate role
its DOC accounts for 45.88% and 32.09% of the total DOC respectively. The optimal oxidation conditions determined in the three oxidation systems were:C/UV/PS system
initial pH
iron ore and PS investment of 3 g·L-1 and 2 g·L-1
ultraviolet irradiation power of 300 W. Under the optimal conditions
COD
UV254
DOC and color removal rate could reach 74.9%
93.5%
84.1% and 80.1% in 90 min. The results showed that C/UV/PS system was more effective in removing organics of MW>10×103
the share of MW<1×103 organics increased after treatment
C/UV/PS system was also effective in removing hydrophobic and transphilic fraction compounds
and the share of hydrophilic substances increased after treatment.