A comparative study on the monovalent and divalent cation separation of polymeric films and membranes from salt solutions under diffusion-dialysis

Authors : Serkan ACAR, Hacer Yesim CENGİZ, Ayca ERGUN, Eymen KONYALİ, Huseyin DELİGOZ

Pages : 1134-1147

View : 21 | Download : 12

Publication Date : 0000-00-00

Article Type : Research Paper

Abstract :This study deals with selective separation of mono- and divalent cations from aqueous salt solutions using polymeric films based on polyethylene insert ignore into journalissuearticles values(PE); and polyamide6 insert ignore into journalissuearticles values(PA6);, and two different commercial nanofiltration insert ignore into journalissuearticles values(NF); membranes. The diffusion rates insert ignore into journalissuearticles values(D); of ions insert ignore into journalissuearticles values(Na+ and Ca2+); , separation factors insert ignore into journalissuearticles values(alpha); and ion rejections insert ignore into journalissuearticles values(R); of the films and NF membranes are examined comparatively as well as their surface morphology and hydrophilicity. It is observed that the diffusion rates of Na+ are in the range of 0.7-1.8 x 10insert ignore into journalissuearticles values(-8); cminsert ignore into journalissuearticles values(2);.sinsert ignore into journalissuearticles values(-1); in the decreasing order of PE > NF90 > NF270 > PA6 while Ca2+ shows diffusion rates of 7.4-18.4 x 10insert ignore into journalissuearticles values(-8); cminsert ignore into journalissuearticles values(2);.sinsert ignore into journalissuearticles values(-1); in the increasing order of NF270 > NF90 approximate to PA6 > PE. Rejection values of the polymeric films and NF membranes against to Na+ and Ca2+ vary between 90% and 99.6%.The highest alpha insert ignore into journalissuearticles values(Ca2+/Na+); is found to be 20 for PA6 film D, alpha, and R value of both polymeric films and NF membranes are strongly affected by the existence of osmosis during diffusion-dialysis and the sizes of hydrated sodium and calcium ions. In conclusion, the film based on PA6 may be a good alternative for selective separation of mono- and divalent cations.
Keywords : Ion separation, diffusion, polymeric films, nanofiltration membranes, separation factor