Biosorpcija odabranih teških metala kompostom Myriophyllum spicatum

Abstract

U okviru ove doktorske disertacije ispitana je mogućnost primene invazivne korovske akvatične biljke Myriophyllum spicatum i komposta nastalog mikrobiološkom razgradnjom ove biljke, kao biosorbenata za uklanjanje odabranih teških metala iz vodenog rastvora. Biljka potiče iz Savskog jezera, Beograd, Srbija, a kompost sa deponije na koju se odlaže ova biljka, posle košenja. Za biosorpciju Pb(II) primenjeni su Myriophyllum spicatum i kompost, dok je za simultano uklanjanje odabranih teških metala, Pb(II), Cu(II), Cd(II), Ni(II) i Zn(II), iz vodenog rastvora korišćen kompost. Analiziran je proces biosorpcije u šaržnom sistemu, variran je veći broj parametara koj utiče na proces, izvršena je karakterizacija primenjenih biosorbenata, određeni su model ravnotežne izoterme i kinetički model, kojima se može najbolje opisati proces biosorpcije. Oba primenjena biosorbenta su prvi put okarakterisana u okviru ovih istraživanja, primenom većeg broja instrumentalnih tehnika, skenirajuća elektronska mikroskopija (SEM), energodisperzivni detektor X-zraka (EDS), Infracrvena spektroskopija sa Furijeovom transformacijom (FTIR), rendgenska difrakciona analiza (XRD), Termijska analiza (TGA/DTA). Određivanje koncentracije jona odabranih teških metala u vodenom rastvoru vršeno je primenom atomske apsorpcione spektroskopije (AAS). Najbolje slaganje eksperimentalnih vrednosti dobijenih ispitivanjem biosorpcije Pb(II) sa biljkom Myriophyllum spicatum i njenim kompostom bilo je sa Sipsovim modelom izoterme, a za oba materijala kinetika procesa je pratila model pseudo-drugog reda. Kapacitet biosorpcije Pb(II) bio je 0,287 mmol/g za kompost, a 0,234 mmol/g za biljku. Afinitet primenjenog biosorbenta prema ispitivanim metalima, opadao je u nizu: Pb(II)>Cu(II)>Zn(II)>Cd(II)>Ni(II). Najbolje slaganje eksperimentalno dobijenih vrednosti je bilo sa Sipsovim izotermnim modelom, za koji su vrednosti koeficijenta determinacije bile bliske 1. Kinetika procesa biosorpcije odabranih metala prati model...

In this doctoral thesis, a possibility was examined to use the invasive aquatic weed plant Myriophyllum spicatum and its compost, generated from microbial degradation, as biosorbent for the removal of selected heavy metals from aqueous solution. The plant was harvested from the Sava Lake in Belgrade, Serbia, and the compost was collected from the open landfill where it is disposed. Myriophyllum spicatum and its compost were applied for Pb (II) biosorption, whereas for the simultaneous removal of, Pb(II), Cu(II), Cd(II), Ni(II) and Zn(II) from aqueous solution only compost was used. Biosorption proces in a batch system was analyzed by applying various batch processing parameters, which affect biosorption. Besides, the applied biosorbents were characterized and the equilibrium isotherms and kinetic models, which best describe the process of biosorption, were determined. In these investigations both applied biosorbents were characterized for the first time, with different instrumental techniques: Scanning electron microscopy (SEM), Energy dispersive X-ray spectroscopy (EDS), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction techniques (XRD), and thermal analysis. The analytical measurements of selected heavy metal ions concentration in aqueous solution were made by using Atomic absorption spectroscopy (AAS). The best fit of experimental data, obtained from the study of Pb(II) bosorption with Myriophyllum spicatum and its compost, was achieved when Sips isotherm model was used, whereby the process kinetics of both biosorbents followed a pseudo-secondorder kinetic model. Lead binding capacity of the compost was 0.287 mmol/g and of the plant 0.234 mmol/g. The affinity of the tested metals to the applied biosorbent was in descending order: Pb(II)>Cu(II)>Zn(II)>Cd(II)>Ni(II). The best fit of the experimentally obtained data was when Sips isotherm model was applied for which correlation coefficients were close to 1 (one). The kinetic studies indicated that the biosorption process of the metal ions followed well pseudo-second-order model, for which experimentally obtained...