Comparative Study on Heavy Metals Biosorption by Different Types of Bacteria

Abstract

Biosorption of Cd(II), Ag(I) and Au(III) by cyanobacteria Spirulina platensis, of Au(II)-by Streptomyces spp. 19H, and of Cr(VI) and Cr(III)-by Arthrobacter species was studied by using the dialysis and atomic absorption analysis under various conditions. In particular, the impact of the following parameters on biosorption was studied: pH (for Ag, Cd, Au), living and non-living cells (for Cr), heavy metal valence (for Cr), homogenized and non-homogenized cells (for Au), Zn(II) ions (on Cr(VI)-Arthrobacter species). It was shown that biosorption efficiency of Cr(III), Cr(VI), Cd(II), Au(III) and Ag(I) ions is likely to depend on the type of bacteria used as well as on the conditions under which the uptake processes proceeded. It was shown that metal removal by microorganisms was influenced by physicalchemical parameters. The pH value of 7.0 was optimum for the removal of Ag(I) and Cd(II) by Spirulina platensis. At a low pH value of 5.5, Au (III) was by test algae more efficiently than Cd(II) and Ag(I).

SIMULTANEOUS EFFECTS OF Cd(II) AND Pb(II) IONS AND γ-IRRADIATION ON STABILITY OF Spirulina platensis

“…The Cd(II)-Spirulina platensis system sorption constant value exceeds the value given for Pb(II)-Spirulina platensis system in the nutrient medium. 10,11 The biosorption constant for Cd(II) -Spirulina platensis was dissolved in the medium at pH 8.6 was 5.1·10 -4 M. We foundus that the efficiency of Cd(II) ions biosorption depends on the conditions of the uptaking processes, 10,11 especially, the pH is an essential factor for Cd(II) binding of Spirulina platensis.…”

“…Figure 5 illustrates the absorption spectra of the intact cells of the Spirulina platensis as a control, (1) after 7.2 kGy irradiation for 7 days, (2) control after 7.2 kGy -irradiation in the presence of Pb(II) ions, and (3) control after 7.2 kGy irradiation in the presence of Cd(II) ions. After irradiation, the peak intensities were decreased as follows: by 20,11,22 and 28 % at 681, 620.7, 500 and 440 nm, respectively, for Cd(II) ions in comparison to the irradiated control. As for Pb(II), the peak intensities were decreased by 14, 7, 18 and 20 % at the given wavelengths, respectively.…”

“…6,7 Spirulina platensis may be able to reduce many types of harmful stresses, including those caused by heavy metals and irradiation. 8,9 In our previous works, the accumulation and biosorption of metal ions by Spirulina platensis and their components [10][11][12][13] as well as Spirulina platensis usability as a matrix for production of noble metal nanoparticles 14,15 have been studied.…”

New Adsorbents Developed From Natural Clays to Remove Ni (Ii) From Wastewater

“…Various low cost adsorbents have been employed for removal of heavy metals from wastewater, including bentonite, coir pith, expanded pert lite, fly ash, magnate, montmorillonite, peat moss and smectite [7][8][9][10][11]. Clays are known as low-cost materials with higher surface area, making them good adsorbents.…”