Your search resulted in 250 documents. Displaying 25 entries per page.
Effect of compression wood on leaching of chromium, copper, and arsenic from CCA-C treated red pine (Pinus resinosa Ait.)
2000 - IRG/WP 00-30232
In this study, the effect of compression wood formation on the release rate of chromium, copper, and arsenic elements from red pine (Pinus resinosa Ait) was investigated. Wood blocks from red pine containing compression and normal wood portions were treated with a 1.0% CCA-C solution and were then allowed to fix at 23 ± ??2°C (74 ± 4°F) for 0, 6, 24, 48, 96, 192, and 336 hours. After each fixa...
S N Kartal, S T Lebow
Copper based water-borne preservatives: Copper adsorption in relation to performance against soft rot
1987 - IRG/WP 3452
As part of a fundamental study concerned with the performance of copper based water-borne preservatives the adsorption of copper from aqueous solutions by 4 hardwood and 1 softwood species has been studied. Experiments were conducted to determine the influence of solution pH, solution concentration and solution temperature. The results obtained were consistent with an acid form ion-exchange mechan...
P M S Rennie, S M Gray, D J Dickinson
Industrial fixation of chromium based wood preservatives
1990 - IRG/WP 3630
Fixation is an abstract and non-defined process. Nevertheless it is a specified requirement in most impregnation standards. The impregnation industry is facing increased pressure to deliver fixed products and to increase the safety of the handling of impregnated products. Industrial fixation of impregnated wood can be obtained by using different methods. The purpose of the process is to transform ...
T Christensen
A diffusion and reaction model for the leaching of Cr-VI from unfixed CCA-treated wood
2001 - IRG/WP 01-50169
A physical model applicable to the leaching of any substance undergoing a first-order fixation reaction with wood is presented. Using this model and a laboratory leaching experiment with small wood samples immersed in water, the radial and tangential diffusion coefficients and the reaction rate constants of Cr-VI in unfixed CCA-treated red pine (Pinus resinosa Ait.) are measured. Reaction rate con...
L Waldron, P A Cooper
The multi-phase pressure (MPP) process. One-stage CCA treatment and accelerated fixation process
- The process as a new concept in preservative treatment
1997 - IRG/WP 97-40078
The background to current commercial CCA treatment schedules used in New Zealand and fixation processing is reviewed. The limitations of these conventional practices with respect to treated product quality and CCA solution handling issues are defined. A novel, patented treatment schedule has been developed using a combination of hydraulic and pneumatic pressure phases and hot (~ 75°C) CCA solutio...
K Nasheri, A J Pendlebury, J A Drysdale, H Pearson, M E Hedley
Bibliography on the use of boron compounds for the preservation of wood
1973 - IRG/WP 315
This bibliography is based on an earlier literature survey prepared by J. Thornton and Wm. E. Bruce (O.E.C.D. Document No. 27/DAS/CSI/M/91) which was enlarged and revised for a meeting in Paris in October 1968 (Document 27/DAS/CSI/M554) by Professor W. Bavendamm of Reinbek. The latter (1968) document with its 166 references has now been extended and brought up to date. Acknowledgments are due to B...
R Cockcroft, J F Levy
Evaluation of the efficiency of industrial kiln type CCA fixation chambers
1996 - IRG/WP 96-40063
Six commercial CCA treating plants in Canada were assessed for the fixation efficiency of their hot air fixation chambers. The wood temperature was measured with thermocouples over the fixation period at different locations in the chamber and at the end of the fixation cycle, the degree of chromium fixation was determined by a boring leaching procedure. There was a great variation in the effective...
A Taylor, P A Cooper
The effect of added nutrients on growth rate and decay capacity of Serpula lacrymans
1990 - IRG/WP 1427
At the previous meeting a new technique was presented that enables both fungal growth rate and wood decay rate to be measured using the same timber specimen. The technique (IRG/WP/1384) has previously been carried out with 1% malt as the sole nutrient within the small jar that provides the inoculum for this method. Results presented here relate to an additional level of 5% malt, with or without a ...
J D Thornton, A McConalogue
Investigation of CCA fixation in wood by sequential extraction. I Determination of CCA component fixation and preliminary extraction results
2002 - IRG/WP 02-50188
The fixation of CCA-C preservative was investigated in sapwood of red pine (Pinus resinosa Ait.), trembling aspen (Populus tremuloides Michx.) and red maple (Populus tremuloides Michx.) at target retentions of 4.0, 6.4, 9.6 and 30.0 kg/m3. Treated wood sawdust was water extracted at close time intervals during the fixation and analyzed for the contents of unfixed hexavalent chromium, total Cr, Cu ...
S Radivojevic, P A Cooper
Kiln drying of LSOP treated timber: rate of solvent evaporation, overpaintability and recovery of the solvent
1992 - IRG/WP 92-3711
The rate of solvent evaporation from LOSP treated timber dried in a kiln at 35°C has been investigated. Around 50% solvent removal has been found to be consistent with good overpaintability using a water based acrylic primer. It has been demonstrated that an activated carbon solvent recovery system is capable of removing all the solvent vapour from the outlet of a commercial joinery drying kiIn, ...
P Warburton, L B Sheard
Remediation of environmental impacts related to inorganic wood preservative chemicals using in-situ geochemical fixation
2001 - IRG/WP 01-50166-17
Use of the inorganic wood preservative chemical chromated copper arsenate (CCA) has resulted in several documented cases of soil and ground water contamination at wood treatment plants due to spills or releases of the treatment chemical. The most significant impact from releases of CCA to the environment is related to hexavalent chromium contamination of ground water. This is due to the relative s...
R M Thomasser, J V Rouse
Leaching of CCA from Bombax ceiba catamarans in operation for 15 years
2002 - IRG/WP 02-50191
Core samples of wood at random were collected from all the timber pieces of each of the three catamarans made of CCA treated logs of Bombax ceiba put to continuous service for the last 15 years at the Lawson's Bay fishing village, Visakhapatnam. The samples were dried to constant weight, powdered, digested and analyzed for the residual salts of the preservative. The residual content of ...
V Kuppusamy, M Balaji, M V Rao, K S Rao
Borates as wood preserving compounds: The status of research in the United States
1989 - IRG/WP 3542
This paper describes the extensive, on-going cooperative research effort among government and university research laboratories and industry to fully evaluate the potential for borates as wood preservatives in the United States. Research is discussed in terms of laboratory evaluations, field testing and mill trials, pilot plant pressure treatment studies, and remedial treatments. Future research pl...
H M Barnes, T L Amburgey, L H Williams, J J Morrell
Five years field test results for CCA and ACQ preservatives fixed in different climates
1999 - IRG/WP 99-30208
During assessment of the ground contact stakes in the Norwegian test field, we have found that very often the first visual rot attack is in the zone of the stakes were the stakes have been in contact with each other during the fixation. These parts are usually light green, caused by the lack of light during fixation, compared to the rest of the stake surface, which has a darker colour. To investig...
F G Evans
A comparative analysis of Coniophora olivacea (Fr. ex Pers.) Karst. and Coniophora puteana (Schum. ex Fr.) Karst. test strains
1993 - IRG/WP 93-20004
Investigations were carried out to compare pure cultures of Coniophora olivacea (Fr. ex Pers.) Karst. used as a test fungus in Australia and other Pacific countries, and Coniophora puteana (Shum. ex Fr.) Karst. which is used in Europe. Comparisons included morphology, growth rate and dry mass of mycelium, decay capacity, influence of temperature, toxic value of CCA and quaternary ammonium compound...
J Wazny, L J Cookson
Investigation of temperature effect on fixation of Celcure preservative (ACC) in Hornbeam (Carpinus betulus I)
2003 - IRG/WP 03-30304
In this research, the fixation speed of Celcure 2 % (ACC) preservative salt, under temperature of 30 ºC, 40 ºC and 50 ºC on intact wood specimens of hornbeam was investigated. For this purpose, blocks of wood with 2Í 2 Í2 cm dimensions of hornbeam were prepared and saturated with 2% ACC concentration by full-cell process. The specimens were put in three incubators at the above-mentioned temperatures. For measuring the percentage of fixation through time, the specimens were extracted by using hydraulic pressure equipment, under 70 Mpa pressure. The PH of extraction was measured with the method of Diphenyl Carbazid and by using spectrophotometer. This measurement was done continuously and the amount of 6-valence chromium concentration present in the extract was compared with the amount of chromium concentration in the primary solution and then the percentage of fixation was calculated.
The results showed that the decrease in 6-valence chromium is accompanied with increase of PH, this due to absorption of positive hydrogen ion by 6-valence chromium for reduction to 3-valence chromium and also ion –exchange of active components with wood during the primary phase of fixation. Also, the time necessary for reaching complete fixation in intact wood in the fixation temperature conditions of 30, 40, 50 ºC were 98, 52, 24 hours, respectively. In general, the results showed that temperature has effective role accelerating of fixation process.
R Imani, R E Majdar, A Karimi
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
A comparison of fungal strains used in the bioassay of wood preservatives
1984 - IRG/WP 2220
Previously published data are presented relating to a number of strains of wood-destroying basidiomycetes (Coniophora puteana, Coriolus versicolor, Gloeophyllum abietinum, Gloeophyllum sepiarium, Gloeophyllum trabeum, Lentinus lepideus, Poria placenta, Fibroporia vaillantii and Serpula lacrymans) commonly used as test fungi in the bioassay of wood preservatives. The data, which has not been statis...
J Wazny, H Greaves
Soft rot test of copper/chrome/arsenic treated heartwood of three Malaysian timbers by the vermiculite-burial method. (+ correction document of 25 July 1990)
1990 - IRG/WP 2354
Heartwood of copper-chrome-arsenic (CCA) treated kempas (Koompassia malaccensis), tualang (Koompassia excelsa) and keruing (Dipterocarpus spec.) was found to be susceptible to soft rot in recent pole surveys. Standardized heartwood blocks were impregnated with 0 to 6.3% (w/v) CCA and challenged to decay for twelve weeks by a mixed inocula of Chaetomium globosum, Glenospora graphii, Humicula grisea...
R-D Peek, A H H Wong
Multiple-Phase Pressure (MPP) Process: One-stage CCA treatment and accelerated fixation process. 4. MPP compared with other processes for achieving acceptable treatment of radiata pine heartwood
1998 - IRG/WP 98-40115
Although radiata pine sapwood is very amenable to preservative treatment, it is often difficult to achieve the required standard for heartwood treatment.
A preliminary investigation showed that to achieve the NZ Timber Preservation Council minimum penetration requirements for radiata pine heartwood using the Multiple-Phase Pressure (MPP) Process, a hydraulic pressure of at least 1250 kPa for 20 m...
K Nasheri, J A Drysdale, G Durbin, M E Hedley
Differential retention and leaching of CCA (C) in sapwood and heartwood of Kenyan-grown blue gum (Eucalyptus saligna) and black wattle (Acacia mearnsii)
2005 - IRG/WP 05-30371
Retention and leaching of CCA(C) in small samples of sapwood and heartwood of Kenyan-grown blue gum (Eucalyptus saligna) and black wattle (Acacia mearnsii) were tested under laboratory conditions. Clear samples (100mm x 30mm x 40mm) were removed from the sapwood and heartwood of sampled defect-free and sound plantation trees of the two species. These were separately air-dried to 15% MC, end-seal...
R Venkatasamy
Chemically modified tannin and tannin-copper complexes as preservatives for wood
2001 - IRG/WP 01-30271
The efficacy of Mimosa tannin, chemically modified tannin, and tannin-copper complexes as wood preservatives was studied. When the tannin-ammonia-CuCl2 solutions were impregnated into wood specimens in a one-step procedure, a large quantity of the tannin-copper complex was fixed in the specimens. Little of the complex was leached from specimens by a weathering treatment, and these specimens showed...
H Yamaguchi
Copper based wood preservative - A new approach using fixation with resin acids of rosin
2000 - IRG/WP 00-30249
Copper soaps with carboxylic acid groups of resin acids of rosin were shown to be potential long-term wood preservatives. The principle involved is the attachment of copper to the network formed by the inorganic part of the preservative (rosin) through the -COOH groups. The mechanisms of fixation have been studied, and it has been shown that this association could be obtained : (1) by forming the ...
C Roussel, J P Haluk, A Pizzi, M-F Thévenon
A spectroscopic investigation of copper ethylenediamine fixation in wood
1999 - IRG/WP 99-20160
The fixation reaction which take place between copper ethylenediamine (Cu-en) solution and wood were expolored using X-ray photoelectron spectroscopy (XPS) and Fourier Transformed Infrared Spectroscopy (FTIR). The FTIR spectra revealed that copper reacts with the carboxylic acid and phenolic groups in wood to form stable complexes. The copper ethylenediamine complexes formed in wood were identifie...
Xiao Jiang, J N R Ruddick
The fixation of copper in Pinus sylvestris using the sodium salts of two polyhydroxycarboxylic acids
1992 - IRG/WP 92-3706
As part of the research concerned with the development of fixed, copper based preservatives, the salts of polyhydroxycarboxyIic acids, have been used in copper sequestration studies and fixation trials in Pinus sylvestris splinters. Selected compounds have been shown to be effective sequestrants at low concentrations allowing alkaline solutions to be formulated. Leaching trials following a 48 hour...
M Bacon, J A Cornfield