As some trace organic contaminants can be bioaccumulated in organisms,poly-3-hydroxybutyrate(PHB),composition of many microorganisms,was used as biomimetic adsorbent to remove polycyclic aromatic hydrocarbons(PAHs) from wastewater.In this study,naphthalene,phenanthrene and pyrene were selected as model compounds.The effects of temperature,reaction time,pH and adsorbent dosage on adsorption capacity and removal efficiency were studied in batch reactors.The adsorption mechanism was investigated by kinetic,adsorption equilibrium isotherms and thermodynamic model.The results showed that the adsorption balance of trace naphthalene(1500 μg · L-1),phenanthrene(1000 μg · L-1) and pyrene(130 μg · L-1) can be achieved in a short time(60,120 and 80 min,respectively).Kinetic data can be fitted well by the pseudo second order model.The adsorption equilibrium isotherms can be fitted by the Henry,Freundlich and Langmuir models,which indicated that there was absorption solution force between PHB and PAHs rather than site adsorption.The results also showed that Kd has a positive correlation with Kow while it has a negative correlation with temperature.Therefore,lower temperature would be helpful to adsorption process.The adsorption of phenanthrene and pyrene by PHB was spontaneous while it was non-spontaneous for naphthalene.In all,the biomimetic adsorption mechanism found in this study might be useful and important to others studies of removing trace contaminants from wastewater.

The contribution of the suspended substance,colloid and dissolved components to residual COD value in the biological effluent of coking wastewater was investigated by the methods of sequential filtration and chemical analysis.The UV-vis spectrum and GC/MS measurements were used to analyze the properties of organic compounds,aiming to establish an evaluation method for the analysis of COD composition in wastewater treatment.The results showed that the major contributions to residual COD values were suspended substance and colloid,and the ratio was 25.9%—46.3% and 18.7%—44.4%,respectively.It was indicated that about 35%—45% of the total COD from suspended and colloid components were removed by coagulation.The COD of dissolved components was 24.6%—40.7% of the total COD,and therein 4.3%—15.8% of the total COD was contributed by the reducing inorganic such as sulphide and thiocyanide.The remaining COD was contributed by chain alcohols,hydrocarbons,esters and other dissolved organic matters.Oxidation and adsorption are the suggested methods for decreasing the COD of the dissolved components in order to satisfy the higher standards.The results also provide an important theory basis for the selection of advanced treatment technologies for coking wastewater.

To investigate the effect of wet oxidation of norfloxacin solution and its product formation during decomposition,thus providing reference for wet oxidation of such antibiotic wastewater,reaction experiments were carried out under the conditions of temperature being 473～513 K,pressure being 3 MPa,initial concentration of NOR being about 500 mg/L,H2O2 quantity being 0 or about 32 200 mg and residence time being 10～60 s,using NORR and TOCR as the evaluation index and LC/MS analysis of decomposition products as the basis.The results showed that NOR could be decomposed efficiently,for example,although at low temperatures and short residence time,NORR and TOCR reached 99.9% and 62.0%,respectively through oxidation reaction in the presence of H2O2,while they reached only 35.9% and 4.1% through pyrolysis reaction in the absence of H2O2.TOCR increased with the increases in the temperature and residence time.Nine major decomposition products,with molecular formula as C16H18FN3O5,C16H18FN3O3,C8H10FN3O,C8H10FN3 and so on,were observed in the oxidation process,which were formed through the decomposition of the piperazinyl substituent or naphthyridine moiety in NOR by hydroxyl radicals.