REMOVAL OF TRACE PHTHALATE ACID ESTERS IN WATER BY NANOFILTRATION MEMBRANE

Phthalate acid esters are a sort of environmental estrogenic hormones,which has a significant effect on people's hormone systems.With DEHP,DCHP,DBP,DEP as studied objects,the effect of solution parameters(pH,ionic strength and concentration) and operation pressure on the retention of trace PAEs by nanofiltration membrane(NF)(BDXN-90 polyamind aromatic compound membrane) filtration process were investigated.Experimental results indicated that the trace PAEs in water could be removed very effectively by NF,the average removal rate was above 90%.The removal of PAEs increased with the increment of the molecular weight;pressure,pH and ionic strength played an important role in removal of PAEs,but concentration had not obvious influence on the membrane performance.The optimal conditions are: the pressure is 0.4 MPa,pH=7,the electric conductivity rate is 0.2 μS/ cm.