Study On The Key Technology Of Enhancing Degradation And Adsorption Of Phenol In Wastewater By Electric Field

Phenol is a kind of toxic organic matter,widely exists in petrochemical,coking,pharmaceutical,printing and dyeing industrial wastewater.Phenolic wastewater has a wide pollution range and great harm,bringing harm to human body,water body,fish and crops.Moreover,phenol is difficult to be removed from industrial wastewater,not only because phenol is difficult to degrade,but also because there are a variety of inorganic salts in the wastewater that coexist with phenol,such as sodium salt.Combining electrostatic field with traditional wastewater treatment technology(degradation method and adsorption method)can effectively improve the removal rate of phenol,but this technology is only in the experimental stage and the microscopic mechanism is still unclear.In order to solve this problem,the mechanism of electrostatic field’s effect on phenol degradation and adsorption efficiency,as well as the influence mechanism of inorganic salts or electrostatic field in the presence of inorganic salts on phenol adsorption efficiency were studied from the microscopic level by the method of molecular dynamics simulation,which provided a new thought and theoretical support for the optimization of phenol wastewater treatment technology.The main research contents of this paper are:(1)In order to solve lacking the research on microscopic mechanism of the electrostatic field effects on phenol degradation efficiency in wastewater,in the present thesis molecular dynamics simulation method has been carried out to study the micro structure and dynamics characteristics of phenol aqueous solution with an electrostatic field based on the calculation of the radial distribution function,self diffusion coefficient,phenol solution viscosity and hydrogen bonding parameters,and analysed how the change of structural and dynamical properties can effect the microscopic mechanism of electrostatic field on phenol degradation efficiency.(2)In order to study the microscopic mechanism of carbon nanotubes adsorbing phenol enhanced by electrostatic field,in the present thesis the effects of electrostatic field with different intensities and directions(along or perpendicular to the central axis of carbon nanotubes)on the adsorption of phenol by carbon nanotubes were investigated bymolecular dynamics simulation.Based on the calculation of the radial distribution function of carbon nanotubes and phenol molecules,intermolecular interaction energy of carbon nanotubes and the self diffusion coefficient of phenol and water molecules,and analysed how the change of structural and dynamical properties can effect the microscopic mechanism of carbon nanotubes adsorbing phenol.(3)To investigate the effect of electrostatic field on the adsorption of phenol by carbon nanotubes in saline wastewater,in the present thesis the structure parameters,the interaction energy between carbon nanotubes and phenol,the structure of hydrogen bond network and the solution viscosity were calculated by the molecular dynamics simulation method to observe the distribution of phenol molecules around carbon nanotubes and the changes of the interactions between the molecules,and analysed the influence mechanism of inorganic salts or electrostatic field in the presence of inorganic salts on phenol adsorption efficiency from micro perspective.