The present work deals with the bioremediation of a sediment sample contaminated by heavy metals, collected in the Ancona harbour, Italian Adriatic Sea, Mediterranean Sea. Bioleaching of the sediment was performed with a mixed culture of acidophilic, chemi-autotrophic Fe/S oxidising bacteria, in the presence of elemental sulphur as substrate. Such element resulted to be fundamental both for cel...

In the light of an expected supply shortage of rare earth elements (REE) measures have to be undertaken for an efficient use in all kinds of technical, medical, and agricultural applications as well as—in particular—in REE recycling from post-use goods and waste materials. Biologicallybased methods might offer an alternative and supplement to physico-chemical techniques for REE recovery and rec...

A multitude of microbes are involved in the solubilisation of minerals and metals as this approach offers numerous advantages over traditional methods. This strategy is preferred as it is eco-friendly and economical, thus overcoming the drawbacks of the traditional approach of pyrometallurgy. Many different types of bacteria are employed in the process of Bioleaching, which are collectively gro...

in this research work, the zinc extraction was investigated, using bioleaching process from a low grade zinc concentrate which was produced from the accumulated flotation tailings. zinc content was initially upgraded to 11.97% by flotation process. bioleaching experiments were designed and carried out by a mixed culture of acidithiobacillus ferrooxidans, acidithiobacillus thiooxidans, leptospir...

The use of recoverable sulfur particles will enhance the feasibility and reduce the cost of bioleaching process. Three different forms of sulfur particles, powder, pastilles and pellets were used to study the utilization and recovery of sulfur, used as energy source for thiobacilli in the bioleaching process. The Langmuir isotherm was used to explain the adsorption equilibrium existing between ...

Bioleaching, a novel biotechnological process, is used to eliminate heavy metals from contaminated sediments by acidification as well as solubilization of heavy metals. Metals from poor-quality ore and mineral compounds are removed by Bioleaching process, which is simple and low cost effective technology. Acidophilic sulfur oxidizing bacteria (Acidithiobacillus ferrooxidans, Acidithiobacillus t...

In an effort to develop alternate techniques to recover metals from waste electrical and electronic equipment (WEEE), this research evaluated the bioleaching efficiency of gold (Au), copper (Cu) and nickel (Ni) by two strains of Aspergillus niger in the presence of gold-plated finger integrated circuits found in computer motherboards (GFICMs) and cellular phone printed circuit boards (PCBs). Th...

Bioleaching has been employed commercially to recover metals from low grade ores, but the production efficiency remains to be improved due to limited understanding of the system. This study examined the shift of microbial communities and S&Fe cycling in three subsystems within a copper ore bioleaching system: leaching heap (LH), leaching solution (LS) and sediment under LS. Results showed that ...

Bioleaching of heavy metals from contaminated soil using Penicillium chrysogenum strain F1 was investigated. Batch experiments were performed to compare leaching efficiencies of heavy metals between one-step and two-step processes and to determine the transformation of heavy metal fractions before and after bioleaching. The results showed that two-step process had higher leaching efficiencies o...

Leptospirillum sp. str. ZC isolated from bioleaching pulp of zinc concentrate is capable of oxidizing Fe (II) with the optimal temperature of 37oC. In pure culture bacteria is unable to oxidize pyrite, however, its growth together with sulfur oxidizing A.albertensis str.SO-2 significantly enhances the efficiency of pyrite bioleaching. The correlation between pyrite biooxidation and adhesion of ...