Heavy metals fractionation and desorption in pine bark amended mine soils.

The European Community Bureau of Reference method (BCR) was used for evaluating the effects of pine bark amendment (0, 24 and 48 g kg) and ageing (1 and 30 days) on Cd, Cu, Ni, Pb and Zn fractionation, on samples from an acid mine soil. In addition, the stirred flow chamber technique was applied for analyzing heavy metals desorption from the unamended and pine bark amended mine soil. When the unamended soil were not subjected to ageing, the added heavy metals were mainly accumulated as soluble fraction (>90% for Cd, Ni and Zn; 71% for Cu; and 45% for Pb).

Valorization of biosorbent obtained from a forestry waste: Competitive adsorption, desorption and transport of Cd, Cu, Ni, Pb and Zn.

Bark from Pinus pinaster is one of the most abundant forestry wastes in Europe, and among the proposed technologies for its reutilization, the removal of heavy metals from wastewater has been gaining increasing attention. In this work, we have studied the performance of pine bark for heavy metal biosorption on competitive systems. Pb, Cu, Ni, Zn and Cd sorption and desorption at equilibrium were studied in batch experiments, whereas transport was studied in column experiments.

Lithological and land-use based assessment of heavy metal pollution in soils surrounding a cement plant in SW Europe.

We study the influence of phasing out a cement plant on the heavy metal (Hg, Pb and Cr) content in the surrounding soils, taking into account factors often neglected, such as contributions due to local lithology or land use. The range of total Hg was 10-144µg kg(-1), reaching up to 41 and 145mgkg(-1) for total contents of Pb and Cr, respectively. Forest soils showed higher concentration of Hg than prairie soils, indicating the importance of land use on the accumulation of volatile heavy metals in soils.

Study of metal transport through pine bark for reutilization as a biosorbent.

The potential utilization of pine bark as a biosorbent for the treatment of metal-contaminated soils and waters has been evaluated in transport experiments using laboratory columns. Solutions containing the metals Cu, Pb, Zn, Ni or Cd, each one individually and at three different concentrations (2.5, 10 and 25 mM) were tested.

Cr(VI) Sorption/Desorption on Pine Sawdust and Oak Wood Ash.

The objective of this work was to study Cr(VI) sorption/desorption on two by-products from the wood industry: pine sawdust and oak wood ash. The retention/release experiments were carried out using standard batch-type trials. In the sorption-phase experiments, pine sawdust showed 23% sorption when a concentration of 100 mg Cr(VI)ŸL-1 was added, whereas sorption on oak wood ash was 17%.

Pine bark as bio-adsorbent for Cd, Cu, Ni, Pb and Zn: batch-type and stirred flow chamber experiments.

The objective of this work was to determine the retention of five metals on pine bark using stirred flow and batch-type experiments. Resulting from batch-type kinetic experiments, adsorption was rapid, with no significant differences for the various contact times. Adsorption was between 98 and 99% for Pb(2+), 83-84% for Cu(2+), 78-84% for Cd(2+), 77-83% for Zn(2+), and 70-75% for Ni(2+), and it was faster for low concentrations, with Pb suffering the highest retention, followed by Cu, Cd, Ni and Zn.

Cyprodinil retention on mixtures of soil and solid wastes from wineries. Effects of waste dose and ageing.

In spite of its wide-world economic relevance, wine production generates a huge amount of waste that threatens the environment. A batch experiment was designed to assess the effect of the amendment of an agricultural soil with two winery wastes (perlite and bentonite wastes) in the immobilization of cyprodinil. Waste addition (0, 10, 20, 40, and 80 Mg ha(-1)) and different times of incubation of soil-waste mixtures (1, 30, and 120 days) were tested.

Competitive adsorption and transport of Cd, Cu, Ni and Zn in a mine soil amended with mussel shell.

Batch type and column experiments were used to study competitive adsorption-desorption and transport for Cd, Cu, Ni and Zn in a mine soil, both un-amended and amended with mussel shell. Batch type experiments showed that adsorption was affected by the added concentration of the metals, generally following the sequence Cu>Zn>Cd≈Ni. Metal desorbed was a function of the dose of metal added, as well as of the dose of shell amendment, being relevant that even when the highest dose of metal (2300 μM) was added, the 24 g kg(-1) shell amendment caused a drastic diminution in the amount of metal desorbed.