Synthesis of Nitrate Doped Polypyrrole Conducting Polymer Membrane and Fabrication of Passive Sampler to Determine Diffusion of Nitrate and Chloride Through Membrane in Aquatic Ecosystem

Abstract

Nitrate is the most considerable substance in the hydrosphere and high concentration of nitrate can be harmful to the healthy life of creatures and human being. The removal of nitrate from the water is very essential. Therefore this study was focused to synthesis the nitrate doped polypyrrole polymer membrane (PPy-N) and the diffusion of nitrate in the presence of high chloride concentration through the membrane for samples obtained in 5th, 7th, 9th, 11th, 13th days in synthetic freshwater was also studied. Passive samplers have been developed in order to assess water quality over the period of time they have been deployed  and also to simplify sampling and sample preparation processes. Nitrate doped polypyrrole film was synthesized through  chemical polymerization process using Pyrrole and HNO3. The characterization of the membrane was performed by Fourier Transform Infrared Spectroscopy (FTIR). The amount of nitrate and chloride diffused through a nitrate doped polypyrrole films (PPy-N1) were determined using cadmium reduction method and chloride ion selective electrode technique respectively. In order to improve the diffusion of nitrate through the membrane, the laboratory filter paper was used to prepare another nitrate doped  polypyrrole films (PPy-N2). The same techniques that used for PPy-N1 were used to determine diffused nitrate and chloride  through PPy-N2 membrane. The results revealed that, membrane PPy-N2 has exhibited 13.102 ± 0.469 %, 42.969 ± 5.107 %, 55.932 ± 1.579 %, 64.096 ± 2.171 %, and 77.826 ± 1.752 % diffusion of nitrate and 36.989 ± 3.177 %, 43.922 ± 1.823 %, 46.223 ± 0.817 %,  49.042 ± 0.908 %, and 49.679 ± 0.119 % diffusion of chloride through the membrane after 5 days, 7 days, 9 days, 11 days and 13 days respectively. Whereas membrane PPy-N1 exhibited that 11.497 ± 0.715 %, 14.899 ± 1.431 %, 33.932 ± 0.469 %, 35.066 ± 0.592 %, and 42.917 ± 1.875 % diffusion of nitrate and 25.612 ± 1.683 %, 38.959 ± 1.201 %, 36.075 ± 2.151 %, 37.004 ± 2.989 %, and 38.495 ± 1.341 % diffusion of chloride after those days respectively.