Influence of Physicochemical Parameters of Organic Solutes on the Retention and Flux in a Nanofiltration Process

A comparative study of several organic compounds (atrazine, aniline, phenol, and their derivatives, 4−chlorophenol, 4−nitrophenol and 4−nitroaniline), and their removal from aqueous solutions by nanofiltration using an NF−97 polyamide membrane is presented. The aim was to ascertain any correlation between the physical-chemical parameters of the different compounds and the characteristic parameters of the nanofiltration system (permeate flux and rejection coefficient), in order to understand the behaviour of the nanofiltration membrane separation processes and any relevant variables. In a previous work, the rejection coefficient and permeate flux values for phenol, 4−chlorophenol, aniline and atrazine were obtained. These values were used together with the new ones presented for 4−nitroaniline and 4−nitrophenol.