Pretreatment Of Antibiotic Production Wastewater By Combined Process Of Resin Adsorption And Fenton Oxidation

Antibiotic production wastewater has high concentration of pollutants,high biological toxicity,and poor biodegradability,which poses a serious threat to the ecological environment and human health.The treatment of this kind of wastewater has become a hot issue in the field of industrial wastewater treatment.In view of the problem of poor biochemical treatment effect caused by toxic substances such as 8-hydroxyquinoline and o-aminophenol in cephalosporin antibiotic production wastewater,combined process of resin adsorption and Fenton oxidation is studied to reduce the toxicity of wastewater and improve biodegradability.In this study,the hypercrosslinked resin NDA-150 is selected as the adsorbent to investigate its adsorption performance for 8-hydroxyquinoline and o-aminophenol.The adsorption capacity of NDA-150 resin for 8-hydroxyquinoline and o-aminophenol can reach the peak at p H=7.0 and p H=6.4,respectively.The static adsorption results show that adsorption of two substances on the resin are spontaneous exothermic processes,and conform to the Langmuir adsorption isotherm model.The adsorption processes conform to the pseudo second order kinetic model,and the adsorption rate is affected by intraparticle diffusion and membrane diffusion.The presence of inorganic salts in the system has little effect on the adsorption capacity,while the presence of organic substances such as methanol and glycerol can reduce the adsorption capacity.In the binary system of 8-hydroxyquinoline and o-aminophenol at different mass ratios,the total adsorption capacity decreases with the increase of the concentration of o-aminophenol,indicating that there has competitive adsorption and the rein exhibits preferential adsorption to 8-hydroxyquinoline.The synergistic adsorption occurs when the mass ratio of 8-hydroxyquinoline and o-aminophenol is 1:0.1,and the presence of aminophenol in the system increases the total adsorption capacity.The adsorption forces between NDA-150 resin and8-hydroxyquinoline are mainly hydrophobic interaction andπ-πconjugation,while the adsorption force between NDA-150 resin and o-aminophenol is mainly hydrophobic interaction.The dynamic adsorption-desorption results show that NDA-150 resin can effectively remove 8-hydroxyquinoline and o-aminophenol from wastewater and it shows good reusability.In order to study the influence of various factors on the treatment effect of Fenton oxidation,a single factor experiment and an orthogonal experiment with 3 factors and 4 levels are designed to determine the optimal treatment parameters of resin adsorption effluent.The results show that the initial p H has a great influence on the removal rate of COD,and the maximum removal rate is obtained when p H=3.Increasing the dosage of H₂O₂ can significantly improve the removal rate,but the improvement of the treatment effect by excess H₂O₂ is not obvious,and the optimal dosage should be determined under the premise of economy.The removal rate of COD increases rapidly and then slows down with the increase of Fe²⁺dosage.The influence of each factor on the treatment of antibiotic production wastewater by Fenton oxidation is in the order of H₂O₂ dosage>initial p H>Fe²⁺/H₂O₂.The optimum operating conditions are p H=3,H₂O₂ dosage of 70 m L/L,Fe²⁺/H₂O₂=1/8.The results of biological toxicity tests and biochemical respiration curve experiments show that the combined process of resin adsorption and Fenton oxidation can effectively reduce the toxicity of wastewater,improve the biodegradability,and create good conditions for biochemical treatment of wastewater.