Authors : Nedjar Zohir , M. Chikhi , A. Khelfaoui and A.H. Meniai
Abstract: In Algeria, the water becomes more and more rare, more and more assaulted; this country suffers for several decades from the aridity and from the pollution, the industries directly throw out in the natural environment without a preliminary treatment their waste water that volume and degrees of concentration are very variable what disrupts ecological balance and returns the treatment of industrial refusals necessary. The objective that we had settled by beginning this study was to determine the best conditions of complication of heavy metals, namely the pH of environment the complexant power of some ligands, the temperature, the speed of agitation, etc., in order to have a better separation by ultrafiltration. The analysis of the various metals in solution was realized by the volumetric method (Titration by the EDTA, citric and nitric acid). The experimental study of the reaction of complexation of heavy metals by the EDTA allowed us to say that elimination will be more important for the group of cations (Ca2 +, Mg2+, Zn2 +, Cd2 +, Hg2 +, Cu2 +); If the concentration of the ligand increases [ Y4 ] opt = 103 M. If the speed of agitation increases Vagi ( opt ) = 750 tr min 1. If the temperature of environment increases Topt = 50°C. If the pH of environment increases pHopt = 7 (neutral Environment). In our team of search, we were interested to change the ligand ( EDTA) by other ligands (citric acid and nitric Acid), we can directly say that volumetric method does not give results because reaction environment becomes acid and the (Titling) EDTA reacts with protons and there will be also a destruction reaction of the least stable complex. We drew the curves of return on ultrafiltration according to the concentration of the permeat (free cation) supposing that the quantity of the complexed cation is retained with the membrane.
Nedjar Zohir , M. Chikhi , A. Khelfaoui and A.H. Meniai , 2007. Study of the Complexation of Some Heavy Metals in Sight of Their Elimination by Ultrafiltration . Journal of Engineering and Applied Sciences, 2: 1038-1042.