the recovery process of selenium from iranian sar-cheshmeh copper anode slimes employing hydrometallurgical methods has been investigated. the copper anode slimes are made up of those components of  the anodes, which are not soluble in the electrolyte. they contain varying quantities of precious metals like gold, silver, selenium and tellurium. they are being extracted as a by product in the co...

background: this research studied the feasibility of a simple method for extracting gold from central processing units (cpus) of computer circuit boards without solvent. methods: ceramic and composite cpus of computer circuit boards were used. gold was extracted using a hydrometallurgical method in six stages: grinding of cpus, leaching in nitric acid, leaching in aqua regia, removing the exces...

This study aims to understand the acid-leaching behavior of metals from 2 to 4 mm waste printed circuit boards (WPCBs) containing 22.0% ± 1.1 Cu, 6.7% ± 0.2 Ca, 0.68% ± 0.02 Sn, 0.59 ± 0.01 % Pb, 2.71% ± 0.08 Al, 0.22% ± 0.01 Fe, etc.. Copper leaching was increased for sulfuric acid concentrations up to 1.2 mol/L and hydrogen peroxide concentrations of 10.0 vol% for a pulp density of 100 g/L at...

The present work examines leaching of lipoxygenase-1 from soybean flour employing stirred tank vessel. The effect of operating parameters, impellers speed, operational period, temperature, pH and scale-up were considered.The acetic acid pH: 5.2 increased the leaching of lipoxygenase- 1.The sensitivity of agitator speed and geometrical-scale-up on the enzymeleaching has bee...

In present investigation the biological leaching of aluminum by isolated fungi from red mud, the main waste product of the alkaline extraction of Al from bauxite was studied. Biological leaching experiments were carried out using indigenous, date and orange specimen fungi, Aspergillus Niger, Penicillium simplicissimum notatum. Savored Dextrose chloramphenicol Agar (SDA) wa...

Leaching of a low-grade lead and zinc oxide ore was studied by an organic reagent, citric acid. The quadratic mathematical models were developed for the relationship among the influential parameters and lead and zinc recoveries. Leaching rate was strongly affected by the interactive effects of factors. It was also found that the quadratic effects of stirring speed and linear<e...

according to the unique properties and many applications of nano silver powder, it was prepared from acid leaching tail solution. the low value residual gold and silver ions were occurred with fellow heavy metals as pollutants (fe2+, cu 2+ and zn2+) in acid leaching tail solution in mouteh gold mine in iran. preparation of nano silver particles was achieved in two steps: first, by addition of a...

a study of the kinetic analysis of total lead from spent car battery ash by hydrochloric acidleaching has been examined. the physico-chemical analysis of the ash powder was carried outby the inductively coupled plasma-mass spectrometry (icp-ms) and x–ray diffraction (xrd).the effects of the acid concentration, temperature and particle size on the rate of battery ashdissolution have been investi...

The chemical composition and aluminum speciation of sludge incineration residue (SIR) were determined. Cementation of aluminum from sulfuric acid solution using SIR was studied. The results showed that acid-soluble inorganic aluminum was the predominant component in the sludge, and the total leached aluminum increased from 62.2% to 92.9% after incineration. Sulfuric acid dosage and reaction tim...

in present investigation the biological leaching of aluminum by isolated fungi from red mud, the main waste product of the alkaline extraction of al from bauxite was studied. biological leaching experiments were carried out using indigenous, date and orange specimen fungi, aspergillus niger, penicillium simplicissimum notatum. savored dextrose chloramphenicol agar (sda) was used as medium for t...