One concern for recycle and reuse of scrap tires is the leaching of tire constituents (organic and inorganic) with time, and their subsequent potential harmful impacts in environment. The main objective of this study was to examine the leaching of dissolved organic carbon (DOC), dissolved nitrogen (DN), and selected inorganic constituents from scrap tires. Different sizes of tire chips and crum...

The leaching reaction kinetics of weathered crust elution-deposited rare earth with mixed ammonium salts was studied. The in uence of concentration of reagents and particle size of ore on leaching rate was investigated. The results showed that the di usion process and leaching rate could be improved by increasing reagents concentration and decreasing leaching owing rate and particle size. The l...

Quasi-dynamic leaching characteristics of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) from raw and solidified air pollution control (APC) residues were examined via a nine-time multiple leaching test. The effect of injected activated carbon in the APC residues on the PCDD/F leachability was also evaluated. When humic acid solution was used as a leachant, the leaching concentra...

In this study various leaching technologies were applied to extract heavy metals from sludge from the printed circuit board process. These methods included traditional acid extraction (TAE) and microwave assisted treatment (MAT). The target heavy metal was copper. Experiments were performed to determine the acid the leaching efficiency by changing operating conditions, including acid type and c...

A novel energy-saving hydrometallurgical recovery process for copper from electronic scrap employing the Cu(I)-ammine complex has been presented on the basis of a thermodynamic consideration. In order to experimentally explore the feasibility of the leaching stage in this process, the copper leaching behavior from a printed circuit board (PCB) in ammoniacal alkaline solutions has been investiga...

Remediation of heavy metal polluted sediment by extracting the metals with sulfuric acid can be performed as follows: abiotic suspension leaching, microbial suspension leaching, abiotic solid-bed leaching, and microbial solid-bed leaching. Abiotic leaching means that the acid is directly added, while microbial leaching means that the acid is generated from sulfur by microbes (bioleaching). Thes...

Accurate assessment of the fate of salts, nutrients, and pollutants in natural, heterogeneous soils requires a proper quantification of both spatial and temporal solute spreading during solute movement. The number of experiments with multisampler devices that measure solute leaching as a function of space and time is increasing. The breakthrough curve (BTC) can characterize the temporal aspect ...

The gas holdup behavior in a nylon fiber suspension with various fiber lengths (L = 2, 3, and 6 mm) is investigated. Experiments are performed over a range of superficial gas velocities (Ug≤ 18 cm/s) and a range of fiber mass fractions (0 ≤ C ≤ 1.8%) in a 15.24-cm-diameter semibatch bubble column. Day-to-day variations in the gas holdup create difficulties in interpreting the effect of the fibe...