Papers by Keyword: Bismuth Trioxide

Abstract: Silver-zinc slag, containing a lot of Bi, Ag, Cu, Zn, Pb and a little Au, has high comprehensive utilization value. This paper describes a preparation method of high-purity nanometer bismuth trioxide (Bi2O3) from silver-zinc slag by hydrometallurgical method. The results showed that Bi could be effectively leached out from silver-zinc slag using sodium chlorate, hydrochloric acid and sodium chloride as leaching agents, and the leaching rate of Bi was up to 99.03% under the optimum conditions. The contents of Pb2+ and Ag+ in BiCl3 solution could be reduced to about 1mg/L by using silver-zinc slag as reductant and sodium iodide (NaI) as precipitant, respectively. Crystalline form of Bi2O3 is affected greatly by concentration of NaOH, conversion temperature and time. The suitable temperature of BiOCl converting to Bi2O3 was 90 , and the suitable surfactant was polyvinyl alcohol. The average particle size of Bi2O3 obtained was about 86 nm, the purity of Bi2O3 was up to 99.75%, and the yield was 98.21%.

Abstract: Studies on ZnxCu1-xBi2O4(0≤ x ≤0.6) spinels (S1-S5: x = 0.0, 0.15, 0.3, 0.45, 0.6) were done using varieties of structure sensitive techniques. The powder X-ray diffraction (XRD) studies shows formation of cubic phase, a=10.6023 Ǻ, space group, Ia3, Z=3 in all the samples. The IR spectral results show the presence of octahedral[CuO6/2] or [BiO6/2] units and Bi-O, Cu-O, and Zn-O bonds in the samples. From the trend g║>g┴>ge(ge=2.0023) obtained from electron paramagnetic resonance(EPR) lineshapes simulation we conclude that the paramagnetic site in these glasses is Cu2+(3d9) which is in a tetragonally elongated octahedron [O1/2-CuO4/2-O1/2] exhibiting Jahn-Teller distortion having D4h symmetry with orbital singlet 3dx 2-y 2(2B1g) as the ground state.