Improper use of urea may cause environmental pollution through NH3 volatilization and NO3 (-) leaching from urea. Clinoptilolite zeolite and compost could be used to control N loss from urea by controlling NH4 (+) and NO3 (-) release from urea. Soil incubation and leaching experiments were conducted to determine the effects of clinoptilolite zeolite and compost on controlling NH4 (+) and NO3 (-...

This paper discusses the results of Cd, Pb and Ni immobilization using cement. Soil contamination levels were in the range 500 mg/kg to 5,000 rug/kg. and cement ratios were in the range 3% to 18%. The process was highly effective in minimizing the leaching of tested heavy metals. The measured leaching reduction results were as follows: 76% to more than 96% for Pb; 30% to more than 99% for Cd; a...

To evaluate the potential environmental and health implications of leaching of wood preservatives in service under different conditions, there is a need for a predictive model that provides estimates of the rate and extent of leaching over a wide range of exposure conditions. In this paper, we test the hypothesis that preservative component emissions can be modeled on the basis of three easily ...

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...

The influence of microwave heating on the leaching kinetics of chalcopyrite and sphalerite has been investigated. Chalcopyrite is inert to many leaching agents, especially ferric ion media. This mineral is considered to be one of the largest sources of copper, in terms of the scale of availability, and copper is usually extracted by pyrometallurgical processes. However, there has recently been ...

The leaching kinetics of smithsonite ore in acetic acid solutions, an environmental friend, and natural reagent was investigated. The influence of parameters such as reaction temperature, particle size, solid-liquid ratio and acid concentration was studied in order to reveal the leaching kinetics of smithsonite ore. In this study, experimental and statistical methods were carried out in order t...

In this paper, the extraction of vanadium from stone coal by roasting with MgO and leaching with sulfuric acid has been investigated, and the mechanism analysis of stone coal roasting with MgO was studied. The results indicated that under the conditions that the mass fraction of the particles with grain size of 0–0.074 mm in raw ore was 75%, the roasting temperature was 500 ◦C, the roasting tim...

Aiming at the industrial scale development of a Scandium (Sc)-selective leaching process 14 of Bauxite Residue (BR), a sufficiently numerous set of process design aspects has been 15 investigated, by appropriate exploitation of available experimental data. The interpretation of 16 experimental data for Sc leaching yield, with sulfuric acid as the leaching solvent, has shown 17 significant impac...