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Selective reduction of PbSO4 to PbS with carbon and flotation treatment of synthetic galena

Zheng Y.-X., Liu W., Qin W.-Q., Han J.-W., Yang K., Luo H.-L.

Physicochemical Problems of Mineral Processing

2015

Vol. 51, iss. 2

535--546

In order to recover lead from the zinc leaching residues, a new technology involving selective reduction of lead sulfate to lead sulfide with carbon followed by flotation was investigated. The reduction thermodynamics of PbSO4 was discussed and the effects of molar ratio of C to PbSO4, reaction temperature and time were examined by thermogravimetry (TG) and XRD. Verification tests were further carried out to prove the conclusions of thermodynamic and TG analyses, and the transformation extent could reach 86.45% under the optimal roasting conditions. The prepared galena was then subjected to micro-flotation tests, and the highest lead recovery could reach up to 75.32%.

Nanoparticles of lead sulfide in porous glasses prepared by the sol-gel method

Reisfeld R., Sarajdarov T., Minti H., Wodnicka K.

Optica Applicata

2003

Vol. 33, nr 1

61-73

PbS semiconductor nanoparticles were grown inside the matrices of zirconium oxide (ZrO2) and zirconium-silica-polyurethane (ZSUR) prepared by the sol-gel method. Zirconium ormosil included polyurethane used to control the growth and aggregation of PbS nanoparticles. The new matrix allows the incorporation of up to 40% PbS forming a characteristic structure of dendrite by reacting lead acetate with ammonium thiocyanate in the sol-gel matrix. The sol precursors of the matrix for ZSUR contain ZrO2 matrix solution, epoxy-silica-ormosil (ESOR) and diurethane siloxane (DURS) synthesized separately. The size of nanoparticles as determined by transmission electron microscopy (TEM) ranges between 2–4 nm for 20% PbS in zirconium oxide and 8–10 nm for 20% PbS in ZSUR matrices. The porosity of the glasses is determined using the nitrogen adsorption technique. The pore size for ZSUR doped with 2% of PbS as determined by BET is 1.54 nm. Quantum size effect was observed from the shifts of absorption and photoluminescence (PL).