Bioflotation of pyrite with bacteria Thiobacillus ferrooxidans in thepresence or absence of potassium ethyl xanthate was studied on a pure pyrite through microflotationand electrophoretic light scattering measurements...Bioflotation of pyrite with bacteria Thiobacillus ferrooxidans in thepresence or absence of potassium ethyl xanthate was studied on a pure pyrite through microflotationand electrophoretic light scattering measurements. The experimental results showed that in theabsence of xanthate, pyrite flotation is slightly enhanced by Thiobacillus ferrooxidans. However,with xanthate as a collector, pyrite flotation is strongly depressed after being exposed to thebacteria. The longer is the time when the pyrite is exposed to the bacteria, the stronger thedepression is. The mechanism of the depression might be due to the formation of the biofilms ofThiobacillus ferrooxidans on pyrite surfaces, preventing the adsorption of xanthate on pyritesurfaces in the form of dixanthogen or xanthate ions.展开更多
This paper presents some results of zeta potential measurements performed into biosurfactant adsorption onto magnesite and serpentinite surface. Zeta potential and isoelectric point measurement of magnesite and serpen...This paper presents some results of zeta potential measurements performed into biosurfactant adsorption onto magnesite and serpentinite surface. Zeta potential and isoelectric point measurement of magnesite and serpentinite particles before and after interaction with biosurfactant broth solution and activator (nickel(II) ion solution) were carried out. The zeta potential results show that presence of biosurfactants changes both magnesite and serpentinite surface potential by physical adsorption which increases the hydrophobicity of mineral particles. Measurements of particles zeta potential in the presence of biosurfactant broth are relevant to the minerals flotation. Hallimod flotation response of magnesite and serpentinite as a function of collector concentration was investigated. Bioflotation test results show that at the presence of broth, the flotation separation of magnesite from serpentinite is possible.展开更多
文摘Bioflotation of pyrite with bacteria Thiobacillus ferrooxidans in thepresence or absence of potassium ethyl xanthate was studied on a pure pyrite through microflotationand electrophoretic light scattering measurements. The experimental results showed that in theabsence of xanthate, pyrite flotation is slightly enhanced by Thiobacillus ferrooxidans. However,with xanthate as a collector, pyrite flotation is strongly depressed after being exposed to thebacteria. The longer is the time when the pyrite is exposed to the bacteria, the stronger thedepression is. The mechanism of the depression might be due to the formation of the biofilms ofThiobacillus ferrooxidans on pyrite surfaces, preventing the adsorption of xanthate on pyritesurfaces in the form of dixanthogen or xanthate ions.
文摘This paper presents some results of zeta potential measurements performed into biosurfactant adsorption onto magnesite and serpentinite surface. Zeta potential and isoelectric point measurement of magnesite and serpentinite particles before and after interaction with biosurfactant broth solution and activator (nickel(II) ion solution) were carried out. The zeta potential results show that presence of biosurfactants changes both magnesite and serpentinite surface potential by physical adsorption which increases the hydrophobicity of mineral particles. Measurements of particles zeta potential in the presence of biosurfactant broth are relevant to the minerals flotation. Hallimod flotation response of magnesite and serpentinite as a function of collector concentration was investigated. Bioflotation test results show that at the presence of broth, the flotation separation of magnesite from serpentinite is possible.