Your search resulted in 109 documents. Displaying 25 entries per page.
A quantitative weathering study of wood surfaces modified by chromium VI and iron III compounds
1989 - IRG/WP 2330
Thin veneers of Pinus radiata were treated with dilute aqueous solutions of chromium VI and iron III compounds and exposed to natural weathering for 35 days. Zero-span tensile strength and weight losses of treated veneers were compared with losses observed in untreated specimens In a study designed to demonstrate the applicability of strength and weight loss measurements to the rapid quantitative ...
P D Evans, K J Schmalzl
The effect of acid rain on CCA treated timber
1990 - IRG/WP 3579
The effect of acid precipitation on the leaching of copper, chromium and arsenic from timber treated with different CCA preservatives was studied in the presence of three types of soil under simulated field conditions. Pine sapwood, embedded in soil, was subjected to simulated rainfall at three different levels of acidity. The CCA preservative formulations tested were:- American Wood Preservers&am...
R J Murphy, D J Dickinson
Recycling and disposal of timber treated with waterborne copper based preservatives
1993 - IRG/WP 93-50008
Recycling and disposal technologies are briefly reviewed. Details are given of chemical extraction techniques suitable for recovery of copper from timber treated with a new copper based preservative, and traditional chromium based products. Details of thermal decomposition tests according to the DIN 53436 protocol under flaming and non-flaming conditions are given. The decomposition products were ...
J A Cornfield, S Vollam, P Fardell
A study of the rate of fixation of various chromium-containing preservatives
1991 - IRG/WP 3653
Denmark, and Scandinavia in general, has perhaps the widest range of approved industrial wood preservative types in the world. As an aid in setting realistic fixation periods, work was undertaken to investigate the rate of fixation of chromium in CCA salt, CCA oxide, CCP, CCB, CC and CCF formulations at summer and winter temperatures. The rate of fixation measured in terms of the concentration of ...
L B Sheard
Inter-laboratory comparison of assessment methods for wood preservatives against subterranean termites: Determination of protection threshold limits for CCA
1999 - IRG/WP 99-10317
In 1996, several institutes conducted laboratory bioassays on the efficacy of unleached Pinus radiata specimens treated with copper-chromium-arsenic (CCA) and copper naphthenate (Cu Naph) at retentions of 0.5, 1.0, 2.0 and 4.0 kg/m3 (total salt for CCA; elemental copper for Cu Naph) against a range of species of subterranean termites (IRG/WP/96-10174). Each participant employed the standard test m...
J W Creffield, M Lenz
Investigation of copper fixation in timber by sodium nitrit
1992 - IRG/WP 92-3707
Solutions containing mixtures of water soluble copper salts and sodium nitrite have been shown to be capable of producing leach resistant copper treatments when impregnated into timber. A rapid leaching trial showed that copper fixation levels of 85-90% were possible which compared well with the fixation level obtained with conventional hexavelant chromium containing systems in the same test regim...
C Waldie, J A Cornfield
Effect of remediation on the release of copper, chromium, and arsenic from particleboard made from CCA treated wood
2001 - IRG/WP 01-50170
This study sought to determine the effect of remediation with oxalic acid (OA) extraction and Bacillus licheniformis fermentation on the release of copper, chromium, and arsenic from particleboard made from remediated wood particles and also investigates durability of the particleboard against white and brown- rot fungi. Particleboard samples were manufactured using untreated, CCA-treated, OA-extr...
S N Kartal, C A Clausen
A comparison of analytical and visual techniques used for assessment of weathering properties of chromium and copper azole treated timber
1994 - IRG/WP 94-20023
The weathering properties of preservative treated timber were studied by measuring surface lignin loss and by microscopic examination after weathering, and results were related to qualitative assessments of visual appearance after weathering. Measurement of relative rates of delignification of untreated and preservative treated timber obtained by FTIR analysis, and weight loss determined on thin v...
J A Cornfield, M D C Hale, G Fettis
Fluoride and chromium concentrations in soil adjacent to remedially treated distribution poles
1996 - IRG/WP 96-50066
Soils adjacent to Rentex treated 'on-line' distribution poles were analysed for total fluoride and chromium content for comparison with background values of these elements. Soil samples 6 cm and 25 cm downslope of selected poles were recovered at 1 week, 1 month, 6 and 12 months after treatment. Background soil samples were taken 50 m from the poles at sampling times. Fourteen po...
D C R Sinclair, G M Smith, A Bruce, H J Staines, P Durrant
Examination of preservative-treated Pinus sylvestris using electron paramagnetic resonance
1992 - IRG/WP 92-3710
EPR is currently being used to help elucidate the nature and extent of the chemical reactions occurring between wood and copper based timber preservatives. In the work reported here treated Scots pine samples were examined at room temperature and in the frozen state. Plots of the electronic parameters A|| vs. g|| were found to be a useful index of the electronic properties of the various formulati...
A S Hughes, R J Murphy, J F Gibson, A J Cornfield
An audit of copper chrome arsenic timber treatment plants throughout Queensland
1995 - IRG/WP 95-50047
Thirty seven copper chrome arsenic (CCA) timber treatment plants in Queensland were assessed according to the operational criteria specified in Australian Standard 2843.2 - 1985, Timber Preservation Safety Code - Plant Operation. The criteria have been designed to provide information on the design and operational activities of a CCA plant. Design aspects that have an effect on the environment are ...
J Norton
The use of low cost X-ray fluorescence instruments in the determination of copper chromium and arsenic in preservative treated wood
1987 - IRG/WP 2278
Internal quality control in timber treatment plants can be pursued by analysis of preservative treatment solutions and treated timber. Treaters must proceed with costly and lengthy analyses through analytical laboratories. An alternative approach for the timber treater, is to use low cost analysers (L.C.A.'s) based upon x-ray fluorescence. Detailed comparisons have been made between stand...
J Norton, L E Leightley
Preservative leaching from copper-chrome-arsenic treated timber: Towards an international standard for environmental monitoring
1996 - IRG/WP 96-50076
A review of standards and legislative requirements around the world relating to environmental contamination from copper-chrome-arsenic wood preservative indicates a plethora of methodologies for expressing and determining contamination levels. The imposition of arbitrary quarantine periods for treated timber, or special fixation processes, appear to be applied without a rational analysis of what l...
S Walley, P R S Cobham, P Vinden
The future for chromium in wood preservation
1985 - IRG/WP 3332
Most water-borne preservatives contain CrVI compounds, originally to reduce corrosion although now also to improve toxicant fixation. Chromium contributes to preservation and this is recognised in, for example, New Zealand and USA where chromium contents are included in calculations of overall preservative activity of CCA formulations, but chromium may also have anti-stain and joinery (millwork) p...
B A Richardson, T R G Cox
A substantively bonded water repellent treatment based on chromium carboxylates
1985 - IRG/WP 3344
Chromium carboxylates soluble in toluene have been synthesised and applied to Scots pine (Pinus sylvestris) sapwood. Without any further treatment, the compounds may be readily leached from wood surfaces with toluene. After a period of heating however, they become fixed to the cell wall, substantial amounts being resistant to leaching even under reflux conditions for several hours. Treatment of wo...
J K Wright, W B Banks, W J Eilbeck
Uptake by grape plants of preservatives from pressure-treated posts not detected
1975 - IRG/WP 350
Leaf and stem tissue and fruit of grape plants (Vitis rotundifolia Michx. cv. Magnolia) were analyzed for copper, chromium, and arsenic, 1, 2, and 3 years after planting 3 inches from copper-chrome-arsenate or fluor-chrome-arsenate-dinitrophenol-treated southern pine posts. Quantities of copper in leaf and stem tissue and fruit of plants next to posts treated with copper-containing preservatives r...
M P Levi, D Huisingh, W B Nesbitt
Electrodialytic remediation of a soil from a wood preservation industry polluted by CCA
1998 - IRG/WP 98-50101-14
Soil contamination is often found at wood preservation sites due to spills, dripping of excess preservatives and deposition of sludge associated with dissolved salts of copper, chromium and arsenic (CCA). The electrodialytic process is a promising heavy metal soil remediation technique. It is based on a combination of the electrokinetic movement of ions in soil with the principle of electrodialysi...
A B Ribeiro, A Villumsen, G Bech-Nielsen, A Réfega, J Vieira e Silva
Changes of copper and chromium content after leaching in wood impregnated with the CCB and CB preservatives
2000 - IRG/WP 00-50147
The objective of the study was impregnated with CCB and CB preservatives pine wood of moisture content varying from 12% to 55% subjected to leaching. Losses of copper and chromium were determined for individual layers of wood up to 3 cm from the girth. The results were compared to the total amount of metals determined in water extracts. The degree of leaching of metal ions from wood of 55% moistur...
B Mazela
Long-Term Release of Arsenic, Chromium, and Copper from CCA-Treated Wood and Ash
2005 - IRG/WP 05-50227
In this study, laboratory long-term leaching studies were conducted to characterize the leaching behavior of arsenic, chromium, and copper from CCA-treated wood samples (block, chip, and sawdust) and CCA-wood ash and to determine the rate of release of the metals from the CCA wood products. The leaching solutions were periodically collected and analyzed for the concentrations of arsenic, chromium,...
Hyunmyung Yoon, Heeseok Kang, Yong-Chul Jang
The susceptibility to sludging of sulfate and oxide CCA
1990 - IRG/WP 3599
Radiata pine sapwood was treated separately with a sulphate CCA-C and an oxide CCA in a pilot scale pressure plant using a full cell process. CCA solutions were recovered from the final vacuum phase, placed in plastic tubes, and their susceptibility to sludging determined by examining changes in solution pH, time required for sludge to form and weight and chemical composition of sludge formed. Sul...
B T Mutandadzi, P D Evans
The influence of UV and IR radiation on leaching of copper and chromium from preservative-treated pine and spruce
1992 - IRG/WP 92-3687
The influence of artifical UV- and IR-radiation on the leaching of copper and chromium components of a CCB-preservative from freshly treated pine and spruce was evaluated. On small pinewood samples it could be shown, that the leaching of copper and chromium can considerabely be reduced by UV-radiation. A Philips HPA lamp type reduced the leaching most effective. IR-radiation lead to higher leachin...
H Militz
Effects of hard water, sea water and humic acid on the release of CCA components from treated wood
2005 - IRG/WP 05-50228
Leaching medium is an important factor affecting release of preservative components from treated wood because physical and chemical characteristics of medium increase or decrease the solubility of fixed preservative components. This study evaluated the leaching properties of copper, chromium and arsenic elements from chromated copper arsenate (CCA)-treated wood specimens subjected to laboratory le...
S N Kartal, W J Hwang, Y Imamura
Wood preservation sites polluted by CCA. Is potassium diphosphate incubation a catalyst for the electrodialytic remediation of these soils?
1998 - IRG/WP 98-50106
As part of an evaluation of a newly developed electrodialytic soil remediation technique, we investigated the incubation of a contaminated soil (from a Portuguese wood preservation site polluted with CCA) with potassium diphosphate as a possible catalyst for the removal of heavy metals and metalloids. A chemical sequential extraction scheme (SE) applied to the soil has shown that the potassium dip...
A B Ribeiro, G Bech-Nielsen, A Villumsen, A Réfega, J Vieira e Silva
The role of chromium in wood preservatives - The situation and new results concerning biological efficacy
2006 - IRG/WP 06-30397
A heavy discussion about the status of chromium-containing compounds in wood preservatives has ensued in the European Union since the Biocidal Product Directive 98/8/EG has come into force.The origin of this discussion is the fact that according to the Biocidal Product Directive chromium trioxide and sodium dichromate have been identified as active ingredients and therefore the placement of wood p...
P Jüngel, H Härtner, E Melcher
Above and Below-Ground Depletion of Copper, Chromium and Arsenic from Pinus radiata and Fagus sylvatica at Thirteen Test Sites in New Zealand and Australia
2006 - IRG/WP 06-30402
The objective was to determine the significance of site and wood species on preservative depletion for a copper chrome arsenate preservative (CCA) from 20 x 20 x 500 mm field test stakes after 5.5 and 4.5 years for pine and beech respectively. At least 5 sacrificial stakes were used to produce site means. Site and wood species had a major effect on copper, chromium and arsenic loss from CCA treate...
R Wakeling