Abstract Bauxite residue (BR) is the main by-product of alkaline production alumina from bauxite containing significant amounts valuable metals such as scandium that belongs to rare-earth elements (REEs), classified by European Community critical raw materials (CRMs). BR considered a hazardous waste due its huge volume and high alkalinity making disposal serious universal environmental problem....

Kaolin is a naturally occurring raw material for several industrial applications. Moreover, the economy of using has some restrictions due to presence iron-bearing impurities in form oxides and hydroxides. This negative effect on whiteness refractoriness products production high purity ceramics. The application microbial leaching been regarded as cheap bio-friendly than conventional methods, he...

The Mouteh refractory pyrite concentrates at pulp densities of 1.5%, 3%, 4.5% and 6% were treated, using Thiobacillus ferrooxidans DSM 581 and the same bacteria adapted on the Mouteh pyritic concentrate. Compared with a non-adapted culture, use of an adapted inoculum of T. ferrooxidans increased bioleaching rate of iron by a factor of 1.940, 2.011, 1.859 and 1.559 for pulp densities 1.5%, 3%, 4...

Soil contamination by heavy metals through the application of a phosphate fertilizer is key issue for sustainable agriculture. Among contaminants, cadmium (Cd) considered most hazardous to human beings’ health and surrounding environment. X-ray diffraction (XRD), combined with binocular mineralogical analysis chemical analysis, was used determine C(I) C(II) layers’ composition. In (+71 µm)-size...

Contamination of heavy metals has been a serious environmental problem due to increasing anthropogenic activities such as mining, smelting, livestock, landfills, waste dumps, and agriculture. Bioleaching experiments were conducted using native Bacillus cereus MAMPE19 BCG, isolated characterized from previous research, test removal arsenic (As) actual mining waste. Mineralogical characterization...

Microorganisms were enumerated and isolated on selective solid media from a pilot-scale stirred-tank bioleaching operation in which a polymetallic sulfide concentrate was subjected to biologically accelerated oxidation at 45 degrees C. Four distinct prokaryotes were isolated: three bacteria (an Acidithiobacillus caldus-like organism, a thermophilic Leptospirillum sp., and a Sulfobacillus sp.) a...

The bioleaching potential of the bacterium Bacillus mucilaginosus and the fungus Aspergillus niger towards industrial residues was investigated by assessing their response towards various heavy metals (including arsenic, cadmium, cobalt, chromium, nickel, lead, and zinc) and elevated pH. The plate diffusion method was performed for each metal to determine the toxicity effect. Liquid batch cultu...

Bioleaching of metal sulfides is an interfacial process comprising the interactions of attached bacterial cells and bacterial extracellular polymeric substances with the surface of a mineral sulfide. Such processes and the associated biofilms can be investigated at high spatial resolution using atomic force microscopy (AFM). Therefore, we visualized biofilms of the meso-acidophilic leaching bac...