title: Bisphenol A removal from aqueous solutions using novel UV/persulfate/H2O2/Cu system: optimization and modelling with central composite design and response surface methodology.
abstract: BACKGROUND
  Bisphenol A is a high production volume chemical widely used in manufacturing polycarbonate plastics and epoxy resins used in many industries. Due to its adverse effects on human health as an endocrine disruptor and many other effects on the various organs of the human body as well as aquatic organisms, it should be removed from the aquatic environments. This study aimed to mineralisation of BPA from aquatic environments by application of novel UV/SPS/H2O2/Cu system and optimization and modelling of its removal using central composite design (CCD) from response surface methodology (RSM).
  
  
  METHODS
  CCD from RSM was used for modeling and optimization of operation parameters on the BPA degradation using UV/SPS/HP/Cu system. Effective operation parameters were initial persulfate, H2O2, Cu2+and BPA concentration along with pH and reaction time, all in three levels were investigated. For analysis of obtained data ANOVA test was used.
  
  
  RESULTS
  The results showed that a quadratic model is suitable to fit the experimental data (p< 0.0001). Analysis of response surface plots showed a considerable impact of all six selected variables which BPA and Cu2+initial concentrations have been the highest and the least impact on the process, respectively.F-value of model was 54.74 that indicate significance of the model. The optimum values of the operation parameters were determined. The maximum removal of BPA was achieved 99.99 % in optimal conditions and in that condition TOC removal was about 70 %. Finally, validation and accuracy of the model were also evaluated by graphical residual analysis and the influential diagnostics plots. The higher relevance between actual and predicted values demonstrated the validation and applicability of the obtained equation as the model.
  
  
  CONCLUSIONS
  According to the results, UV/SPS/HP/Cu system is an effective process in degradation and mineralisation of BPA and CCD methodology is a convenient and reliable statistical tool for optimizing BPA removal from aqueous solutions.
authors.affiliation: Research Center for Environmental Health Technology, School of Public Health, Iran University of Medical Sciences, Tehran, Iran ; Department of Environmental Health Engineering, School of Public Health, Ardabil University of Medical Sciences, Ardabil, Iran.
authors.forename: S Ahmad
authors.initials: SA
authors.lastname: Mokhtari
authors.affiliation: Research Center for Environmental Health Technology, School of Public Health, Iran University of Medical Sciences, Tehran, Iran ; Department of Environmental Health Engineering, School of Public Health, Iran University of Medical Sciences, Tehran, Iran.
authors.forename: Mehdi
authors.initials: M
authors.lastname: Farzadkia
authors.affiliation: Research Center for Environmental Health Technology, School of Public Health, Iran University of Medical Sciences, Tehran, Iran ; Department of Environmental Health Engineering, School of Public Health, Iran University of Medical Sciences, Tehran, Iran.
authors.forename: Ali
authors.initials: A
authors.lastname: Esrafili
authors.affiliation: Research Center for Environmental Health Technology, School of Public Health, Iran University of Medical Sciences, Tehran, Iran ; Department of Environmental Health Engineering, School of Public Health, Iran University of Medical Sciences, Tehran, Iran.
authors.forename: Roshanak Rezaei
authors.initials: RR
authors.lastname: Kalantari
authors.affiliation: Research Center for Environmental Health Technology, School of Public Health, Iran University of Medical Sciences, Tehran, Iran ; Department of Environmental Health Engineering, School of Public Health, Iran University of Medical Sciences, Tehran, Iran.
authors.forename: Ahmad Jonidi
authors.initials: AJ
authors.lastname: Jafari
authors.affiliation: Research Center for Environmental Health Technology, School of Public Health, Iran University of Medical Sciences, Tehran, Iran ; Department of Environmental Health Engineering, School of Public Health, Iran University of Medical Sciences, Tehran, Iran.
authors.forename: Majid
authors.initials: M
authors.lastname: Kermani
authors.affiliation: Research Center for Environmental Health Technology, School of Public Health, Iran University of Medical Sciences, Tehran, Iran ; Department of Environmental Health Engineering, School of Public Health, Iran University of Medical Sciences, Tehran, Iran.
authors.forename: Mitra
authors.initials: M
authors.lastname: Gholami
keywords: Aqueous solutions; BPA; CCD; UV/SPS/HP/Cu