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A comparison of the leaching resistance of diammine-copper complexes and copper carbonate precipitated in wood
1997 - IRG/WP 97-30158
Previous studies have shown that during treatment of wood with ammoniacal copper solutions, both simple copper precipitates and diammine-copper complexes are formed. The objective of the present study is to determine the relative importance of both forms of copper, on such aspects as preservative leachability and biological performance. In the current experiment, the leachability of copper carbonate precipitated in wood is compared with that of diammine-copper complexes. The results confirmed that both forms of copper resisted leaching by distilled water. However, when exposed to the more aggressive leaching conditions using the sodium citrate buffered solution, the diammine-copper complexes were significantly more ressistant to removal from the wood. Further studies are planned to examine the diammine-copper complexes present in the wood as well as the efficacy of these complexes against wood decay fungi.
Xiao Jiang, J N R Ruddick
Rapid leaching test
1991 - IRG/WP 2367
An accelerated test which is suitable for measuring the extent of metal fixation in both chromium and non chromium containing preservatives is described.
J A Cornfield, M Bacon, A Lyman, C Waldie, M R Gayles
The Effect of Heat on the Retention of Ammoniacal Copper Quat (ACQ-AB) onto Scots Pine (Pinus Sylvestris L.) Wood
2008 - IRG/WP 08-40390
In this study, the sapwood of Scots pine (Pinus sylvestris L.) were treated with ammonical copper quat type (ACQ-AB), which is one of the environmentally friendly wood preservatives, by using soaking method as a functions of various temperatures and time. The results indicated that the retention behaviour of ACQ onto the wood was considerably affected by temperature of ACQ solution and treatment time.
M Hakki Alma, A Mukremin Kara
Migration of Metals from Douglas-fir Lumber Treated with ACZA or Pentachlorophenol Using Best Management Practices: Preliminary Tests
2005 - IRG/WP 05-50224-4
The potential for migration of preservative components from ammoniacal copper zinc arsenate (ACZA) and pentachlorophenol treated Douglas-fir lumber in non-soil contact exposure was assessed in a simulated rainfall device. Metal levels from ACZA treated wood were elevated for the first 30 minutes of rainfall and then declined sharply. Repeated cycles of rainfall led to declines in initial metal losses suggesting that surface metals were gradually depleted from the wood. Penta losses were also initially high, but then declined at rates related to rainfall level. The results suggest that preservative losses from treated wood in above ground exposures can be predicted.
J J Morrell, Hua Chen, J Simonsen
EPR investigations of interactions between ammoniacal Cu(II) octanoate and wood
1996 - IRG/WP 96-30110
Ammoniacal solutions of copper(II) octanoate [ C u . h l f . 2 . r h l f.(O2CC7H15)4], interactions of these solutions with wood and wood components, and leaching of copper(II) octanoate from impregnated wood samples, have been studied by electron paramagnetic resonance (EPR) method. It is still not clear if in the Cu(II) octanoate - water - ammonia system, Cu(II) remains in a (copper(II) octanoate - ammonia) complex. The majority of leached Cu(II) with distilled water and a solution simulating acid precipitations was washed out in the first five hours of leaching procedure (up to 35% of initial Cu(II)). Time dependence studies of interactions of ammoniacal Cu(II) octanoate with wood, cellulose and brown rotted lignin showed, that the fastest and most significant was the reaction with lignin. Cu(II) is immobilised also on cellulose. A significant contribution of ammonia evaporation to the fixation mechanism of the preservative was observed as well.
F Dagarin, M Petric, F Pohleven, M Sentjurc
Water-borne preservative marine trials in Western Canada
1981 - IRG/WP 470
Red pine boards treated with chromated copper arsenate, ammoniacal copper arsenate, copper zinc arsenic additive, a modified ammoniacal copper arsenate, and zinc arsenic additive, have been installed in a marine field test at West Vancouver, British Columbia. After two and a quarter years exposure, all the test samples are in excellent condition with the exception of those treated with the zinc arsenic additive. All the zinc arsenic additive treated boards at the lowest preservative retention and two thirds of those at the second lowest retention in test have failed. A performance index calculated for the zinc arsenic additive indicates an added service life of 3% at the standard retention level.
J N R Ruddick
Water-borne wood preservatives against marine borers. Results from NWPC marine trials started in 1972 and 1976
1990 - IRG/WP 4162
The paper presents the results from NWPC (Nordic Wood Preservation Council) marine trials started in 1972 and 1976. The trials are carried out according to the NWPC Standard No. 184.108.40.206./73 "Marine test - a test against marine wood boring organisms in sea water". The test site is Kristineberg Marine Biology Station on the west coast of Sweden. The wood blocks used in the trials were made from sapwood of European redwood (Pinus sylvestris L.). European beech (Fagus sylvatica L.), European birch (Betula spp.) and Norway spruce (Picea abies (L.) Karst) were also used to a minor extent. In all, 19 water-borne wood preservatives were tested. The preservatives consisting of copper-chrome, copper-chrome-arsenic, copperchrome-boron, copper-chrome-phosphorus and tributyltin oxide gave best performance. The ammoniacal copper preservatives failed to protect the wood against marine borers.
Ö Bergman, C Lundberg
Comparative performance of several ammoniacal copper preservative systems
1997 - IRG/WP 97-30151
The efficacy of several ammoniacal copper-based wood preservative systems was evaluated in this study. The selection of potential co-biocides was based on the results of an agar plate test. Following this, the most promising systems were evaluated in a standard field stake test. Good correlation was found between the agar plate and field stake test results. Of the preservative systems tested, copper/tribromophenol, copper/naphthenic acid, copper/DDAC, and copper/propiconizole were found to be superior against copper tolerant fungi in comparison to the other systems tested after three years of field ground-contact exposure. The performance of copper/benzoic acid was mediocre. Copper/citric acid was ineffective against copper-tolerant fungi, with its performance being no better than copper alone.
D D Nicholas, T Schultz
Fungicidal activity of some new water borne copper octanoate based formulations
1999 - IRG/WP 99-30198
Four new water borne formulations for preservation of wood were prepared: the composition of Cu(II) octanoate, 2-aminoethanol (ethanolamine) and water; the composition of complex of Cu(II) octanoate with nicotinamide, 2-aminoethanol and water; the one of Cu(II) octanoate, organic boron complex, 2-aminoethanol, dimethyl sulfoxide and water and finally, the mixture of Cu(II) octanoate, diazene, 2-aminoethanol and water. Fungicidal activity of these new formulations against Trametes versicolor, Antrodia vaillantii and Coniophora puteana was determined by filter paper and mini-block test methods. Compared to the commercially used wood preservative containing Cu(II) naphthenate / Cu(II) 2-ethylhexanoate, the new compositions have stronger fungicidal activity. The strongest biocidal activity was exhibited by the formulation with a Cu(II) octanoate/nicotinamide complex.
M Petric, M Pavlic, F Pohleven, P Segedin, B Kozlevcar, S Polanc, B Stefane, R Lenarsic
A marine borer test with water-borne preservatives
1980 - IRG/WP 452
The use of preservative treated timber in sea-water where marine borers are active is of great economic importance, since untreated wood immediately will be damaged. Vacuum/pressure treated timber has been tested in several marine exposure trials on the Swedish west coast since the 1930s (Hager 1941, Hultman 1949, Sandstrom 1951, Nylinder-Norman et al. 1974). Since new interesting materials or preservative formulations are manufactured all the time, it is important to investigate their effect against the borers before they can be recommended and used in marine wood constructions. A Nordic standard method for testing wood preservatives in the sea was therefore worked out at the beginning of the 1970s (NWPC Standard No. 220.127.116.11./73). In principle following this standard an extensive test was started in 1972 to evaluate the effectiveness of various preservatives against wood borers. The test was located at the Kristineberg Marine Biology Station on the Swedish west coast. Results after the first 2.5 years (three growth seasons) were reported in 1975 (Norman and Henningsson). The present paper deals with the results after an exposure period of 6.5 years (seven growth seasons).
B Henningsson, E Norman
Tests with ammoniacal copper and alkyl ammonium compounds as wood preservatives
1984 - IRG/WP 3299
Formulations based on copper and alkyl ammonium compounds in ammonia solution have been tested in a fungus cellar on Pinus radiata and Fagus sylvatica. This type of products gives promising results as wood preservatives, especially on hardwood and are safe to destroy by e.g. combustion. The best results were achieved with a dialkyl ammonium compound, Cu/octyldecyl dimethyl ammonium chloride (NH3). The optimal weight ratio of Cu/AAC is for Pinus radiata = 0.2-0.4 and Fagus sylvatica = 1.0 based on cost-effectiveness. Fixation and leaching of coppertetrammine are discussed in detail. The leaching of active components from the Cu/AAC/NH3-systems is very low.
The effect of pretreatments on the impregnation of air-dried sawn Belgian spruce
1988 - IRG/WP 3490
In general the impregnation of airdried spruce results in a variable treatment and limited penetration. This is the result of pit aspiration that occurs during drying of the spruce sapwood and heartwood. Spruce timber is becoming of greater importance in Belgium and hence research for better treatment of this vulnerable wood species is needed. Squared airdried timber of different dimensions were extracted from 10 winter-felled logs (Picea abies (L.) Karst) and impregnated with preservative used for constructional purposes. Partly the material was presteamed or waterlogged. Prior to the preservative treatment both groups were reconditioned to the same moisture content as the reference material (airdried). Retention and different penetration parameters showed better figures when only modifying the treating cycle rather than using a pretreatment. Both pretreatments seemed to have no positive effect on the treatability of airdried material. Increasing the strength of the initial vacuum parameters of the full-cell processes improved the degree and homogenity of the penetration of the preservative components.
J Van Acker, M Stevens
Performance of Paraserianthus falcataria treated with ACZA, ACQ, CC or CCA and exposed in Krishnapatnam harbour, India
2005 - IRG/WP 05-30382
Paraserianthus falcataria (=Albizia falcataria) treated to two retentions with ammoniacal copper zinc arsenate (ACZA), ammoniacal copper quaternary (ACQ), ammoniacal copper citrate (CC) and chromated copper arsenate (CCA) was assessed over 34 months in a tropical marine waters at Krishnapatnam harbour on the east coast of India. ACZA treatment showed comparatively better resistance than CCA, ACQ and CC, while CC provided the least resistance to marine borer attack. Eight species of borers i.e. Martesia striata, M. nairi, Teredo furcifera,T. parksi, Lyrodus pedicellatus, Nausitora hedleyi, Bankia campanellata and B. rochi were recorded on test panels. Of these, M. striata, L. pedicellatus, T. furcifera and B. campanellata were the dominant species, while other species settled sporadically. The results suggest that copper based preservatives are less likely to perform well under extreme tropical exposures without arsenic.
B Tarakanadha, K S Rao, J J Morrell
Dimensional stabilization and decay resistance of wood treated with brown-rotted lignin and copper sulfate
1990 - IRG/WP 3608
The objective of this study was to evaluate the potential usefulness of brown-rotted lignin (BRL) as a dimensional stabilization and copper complexing agent for wood treatment. For dimensional stabilization, aqueous solutions of the lignin extract were combined with either copper sulfate, glyoxal or other additives. Anti-shrink efficiency (ASE) values as high as 42% were obtained with wood treated with a BRL/Cu combination. By treating wood with a 6% solution of the lignin extract prior to treatment with copper sulfate, a two-fold increase in fixation of copper was attained. Soil block tests were also performed on wood treated with BRL and copper sulfate individually as well as in combination; it was found that the BRL increased the activity of Cu against Poria placenta.
L Jin, D D Nicholas, T Schultz
Diffusion and interaction of components of water-borne preservatives in the wood cell wall
1988 - IRG/WP 3474
This study investigates the rates of diffusion and ultimate distributions of copper and arsenate components of wood preservatives in wood cell walls following vacuum treatment. Adsorption studies of copper on red pine (Pinus resinosa) and trembling aspen (Populus tremuloides) wood confirm the importance of cation exchange reactions on the ultimate distribution of copper in the wood substance and its strong dependence on pH of the treating solution. Formulations containing both copper and zinc preferentially adsorb or exchange copper relative to zinc. Under high pH conditions, the arsenate anion is significantly adsorbed into the cell wall. The combined adsorption and fixation of low pH CCA solutions is much slower than adsorption of high pH ACA and CZA formulations, but the reaction with wood is more complete. Diffusion coefficients were estimated for the movement of copper and arsenate components of ACA in cell wall material of both aspen and pine sapwood using a simple membrane model for non-steady state diffusion. The longer diffusion paths inherent in the diffuse porous hardwood (aspen) resulted in much slower equalization of the solute in the cell wall matrix than in red pine. However, in both species, equalization was achieved in a relative short time compared to accepted fixation times for conventional waterborne wood preservatives.
P A Cooper
Stake test with ammoniacal copper in combination with different agents started in 1962
1997 - IRG/WP 97-30130
In 1962 a stake test was started with ammoniacal copper in combination with chromium, arsenic, pentachlorophenol, boron, salicylic acid, benzoic acid, sorbic acid, pyridine and tannin. Different concentrations of the copper component were used as well as the added agents. For each concentration and test site, ten stakes of Pinus sylvestris L. sapwood were treated. The stakes were set out at two test fields in Sweden, Simlångsdalen and Bogesund and also in a greenhouse. Today all stakes except five at Bogesund have been rejected. The prevailing type of decay in Bogesund is soft rot and in Simlångsdalen brown rot and soft rot. Ammoniacal copper alone at a copper retention of 1.9 kg/m3 gave an average service life of 23 years in Bogesund and 14 years in Simlångsdalen. When the copper retention was doubled to 3.8 kg/m3 the service lives were prolonged by 2-3 years in Bogesund and 8-9 years in Simlångsdalen. Most of the agents added to copper prolonged the service lives substantially in Simlångsdalen but only marginally, or not at all in Bogesund. The added agents which gave the longest service lives at both test fields were chromium plus arsenic and pentachlorophenol.
B Häger, Ö Bergman
Preservative treatment of green timber by soaking in ammoniacal copper borate
1984 - IRG/WP 3292
Freshly sawn boards of radiata pine sapwood were preservative treated by soaking in ammoniacal copper borate. Optimum schedules were obtained by partially seasoning the boards for one week prior to treatment. This aided the absorption of preservative and reduced the required soaking time to approximately 2 hours. Complete boron penetration was obtained after one week of block storage under cover and air drying. Copper penetration was more limited because of fixation of copper. The preservative treatment system should have particular application in the treatment of coconut timber destined for above-ground use but exposed to the weather.
P Vinden, A J McQuire
Effect of test site location on in-ground preservative performance after 6 years
2001 - IRG/WP 01-20231
Pinus radiata test stakes were treated with 4.1 kg/m3 of CCA and Fagus sylvatica with 6.1 kg/m3 of CCA. Both wood species were also treated with a copper plus triazole preservative (3 kg/m3 of copper) and chlorothalonil plus chlorpyriphos in oil (4.8 kg/m3 chlorothalonil). Furthermore, P. radiata was treated with ammoniacal copper plus a quaternary ammonium compound (2.6 kg/m3 copper) and a 60/40 mixture of high temperature creosote plus oil (61 kg/m3 creosote). Treated and untreated stakes were exposed in the ground at 13 sites in New Zealand and Australia for approximately 6 years. Preservative performance was significantly affected by site and there was a site-preservative interaction effect where decay hazard at a given site was dependent on preservative treatment. For pine, chlorothalonil plus chlorpyriphos, copper-azole and ACQ gave at least equivalent performance to the reference standards creosote and CCA, after approximately 6 years, at the majority of test sites. For beech, chlorothalonil plus chloropyriphos and copper-azole both gave superior protection to CCA, at the majority of test sites. In general, the results suggest that it is possible to select 3 - 4 sites that collectively pose a diverse decay hazard, representative of the majority of situations encountered by wood in service.
R N Wakeling
Biological test, AAS and EPR study of copper monoethanolamine complex with quaternary ammonium compounds as a wood preservative
2003 - IRG/WP 03-30321
Experiments were carried out on the wood preservative with a strong fungicidal activity based on Cu(II) carbonate, 2-aminoethanol (monoethanolamine) and quaternary ammonium compound (QAC). The object of the performed investigations was sapwood of Scots pine (Pinus sylvestris L.) treated with Cu-EA-QAC formulation. Mycological investigations were carried out according to EN 113 and EN 84 standards. The retention of the copper ions in the wood grows nonlinearly with concentration (in %) of the impregnating solution from 0,25 kg/m3 at 0.03% to 1,55 kg/m3 at 0.21% (i.e. nearly 6 times) whereas the copper leachability decreases 2,5 times from 15% to 6% in the same range. These results indicate good fixation of the copper to the wood and high leaching resistance. EPR results and computer simulations of the observed EPR spectra shows that in Cu-EA aqueous solution the Cu(EA)2(H2O)2 complexes exist and the main coordination plane is not destroyed in impregnating solution and in the wood. In Cu-EA-QAC-BA solution the Cu(EA)2(QAC)2 complexes appear whereas EPR spectra of the treated wood indicate coexistence of a few types of Cu-complexes. We have identified strongly fixed Cu(EA)2O2 and Cu(EA)2O complexes with oxygens atoms from wood functional groups.
B Mazela, I Polus, S K Hoffmann, J Goslar
Influence of water-borne preservatives on water repellency and the impact of addition of water repellent additives
1992 - IRG/WP 92-3704
The primary goal of a desirable wood preservative system is to effectively control decay fungi and other biodeteriogens in service. The water repellent nature of a given system may play an important role in the protection of wood. In this study, the water repellency of several water-borne preservative systems has been evaluated by measurements of tangential swelling during immersion. The systems include cuprammonium formulations, such as ammoniacal copper carbonate (AC) and ammoniacal copper zinc arsenate (ACZA), ammoniacal copper quat systems (ACQ) and chromated copper arsenate (CCA). The influence of addition of water repellent emulsions into the above systems has also been examined.
L Jin, D M Roberts, A F Preston
Amine copper reaction with wood components: acidity versus copper adsorption
1997 - IRG/WP 97-30161
The bonding sites for copper in wood from CCA, as well as ammoniacal/amine based systems, has long been a topic of investigation. Both phenolic and carboxylic functional groups have been discussed as potential bonding sites for copper. However, no consensus on the adsorption mechanism has been realized. Thus, the selective adsorption of copper in southern yellow pine from ethanolamine-copper solutions and its correlation to wood acidity is currently being investigated. The wood acidity has been determined by acid/base titration, and is due to more than one type of acidic group. The acid(s) can be removed by thermal treatment or extraction techniques, and, interestingly, the selective adsorption of copper was observed to track the presence of particular acid functionalities. The preferential adsorption of copper and the mechanisms behind such will be discussed.
S M Thomason, E A Pasek
Long term marine performance of ACZA treated Hem fir in Krishnapatnam harbour, east coast of India
2006 - IRG/WP 06-30409
The performance of Hem fir (Tsuga heterophylla) and Southern pine (Pinus sp.) treated with ammoniacal copper zinc arsenate (ACZA) and copper dimethyldithio carbamate (CDDC) at two retention levels of each preservative was assessed in tropical marine waters at Krishnapatnam harbour on the east coast of India. Panels treated with ACZA of lower loadings (23.1 Kg/m3) had failed in 38 months while the performance of higher loadings (38.1 Kg/m3) was very effective and lost in 54 months. Panels treated with CDDC of lower loadings (4.31 Kg/m3) was severely attacked by borers and lost in 22 months and higher loadings (10.86 Kg/m3) damaged in 38 months. The results indicate that, ACZA at higher lodgings is very effective in tropical waters and durability enhanced over 13 times compared with untreated controls. Teredinids were important on control panels, while ACZA treatment was damaged mainly by pholads. Nine species of borers were identified on panel including 2 species of pholads and 7 teredinids. The fouling biomass was slightly higher on CDDC treatments than ACZA and barnacles, bryozoans, oysters and serpulids were dominant groups on test panels.
B Tarakanadha, K S Rao, J J Morrell
Formation and Structure of Metal Azole Complexes
2008 - IRG/WP 08-30469
Divalent copper and zinc complexes with metal:azole ratio 1:2 were readily formed at room temperature with the fungicides tebuconazole and propiconazole. The structure of copper and zinc tebuconazole acetate and zinc cis-propiconazole chloride were examined by X-ray crystallography. In copper tebuconazole acetate, the copper atom lies on a crystallographic inversion centre and is coordinated to two triazole and two acetate ligands in a trans arrangement. The two binding tebuconazole N atoms and two close binding acetate O atoms form a square plane. The two remaining acetate O atoms have more distant interactions, thus forming an elongated octahedron around the copper atom. The coordination geometry of zinc tebuconazole acetate is tetrahedral and the metal is bound to two triazole and two acetate ligands. The geometry is distorted from regular owing to the size of the tebuconazole ligands. The butyl chains are less folded than for the copper tebuconazole complex, resulting in a more extended molecule. The coordination geometry of zinc cis-propiconazole chloride is also tetrahedral with the metal atom bonded to two triazole and two chloride ligands.
P D Evans, K J Schmalzl, C M Forsyth, G D Fallon, S Schmid, B Bendixen, S Heimdal
Mold-resistance Effect of Bamboo Wood Treated with CCC-organic Complexes
2009 - IRG/WP 09-30514
Mold resistant effect of CCA, ACQ, CuAz, CCC and the compound of CCC and propiconazole were researched on bamboo wood of Phyllostachys pubescens were reported in this paper. Results showed that all of the test fungicides could protect bamboo wood better from Penicillam citrinum than from Trichoderma viride and Aspergillus niger. The complex of CCC and propiconazole had the best resisting effect on all of the test mold fungi. ACQ had better resisting effect on Penicillam citrinum, but not so effective on Trichoderma viride and Aspergillus niger, especially on Aspergillus niger. CuAz had better effect only on Penicillam citrinum. CCA and CCC had better resisting effect on Penicillam citrinum only at higher retentions, but had poor effect on the other two test fungi.
Sun Fangli, Yang Le, Chen Anliang, Bao Binfu, Li Qiao
Metal Migration from Douglas-fir Poles Treated with Ammoniacal Copper Zinc Arsenate According to Best Management Practices
2010 - IRG/WP 10-50272
The potential for migration of metal components from ammoniacal copper zinc arsenate treated (ACZA) poles was examined using pole sections treated using Best Management Practices. Copper and zinc levels were highest in runoff collected following the first rainfall events, then declined. Copper and zinc levels in runoff averaged 20 ppm and 5 pm respectively. The metal levels were then used to predict the amount of metal loss when poles were stacked in different configurations that altered exposed surface area. Tight stacking reduced total metal losses, although metal levels would still rise well above background within 150 mm of the surface beneath the poles if no dilution occurred into the surrounding soil. The results illustrate the potential for managing poles to reduce metal losses in storage.
J J Morrell, C S Love, C Freitag