• Journal of the Korean Wood Science and Technology
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• v.23 no.3
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• pp.66-72
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• 1995

The rate of fixation of the components were evaluated in CCA-Type B and CCFZ-treated radiata pine sapwood by quantitative analysis of solution expressed from the treated wood. The leaching characteristics of radiata pine blocks treated with CCA-Type B and CCFZ were also evaluated by the AWPA standard leaching test. Both fixation and leaching charactersistics of CCA-Type B were compared with CCA-Type C treated wood samples. The rate of CCA-Type B fixation was a little faster than that of CCFZ. However, significant amounts of arsenic was unfixed in the CCA-Type B treated samples and consequently leached. These significant quantities of arsenic liberated from the CCA-Type B treated wood during service may pose some environmental concerns. Arsenic was no longer detectable from CCA-Type C treated samples when fixation was complete, even though the fixation of CCA-Type C was slower in some degree than CCA-Type B. In summary, it could be said that CCFZ was much safer preservative than CCA-Type B by the criterion based on the relative hazard assessed by absolute amount of unfixed element present in the treated wood. Also the decision that CCA preservative has to move from Type B to Type C should be made sooner or later for continuous use of CCA preservative in the future.

• Journal of the Korean Wood Science and Technology
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• v.35 no.5
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• pp.87-92
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• 2007

For the safe disposal of the end used CCA treated wood, the biological method was studied. Aspergillus niger has been known to be grown on the fresh wood surfaces even on the CCA treated wood surface. Therefore, in this study we estimated the removal efficacy of heavy metals from CCA treated wood by A. niger. The selected fungi, A. niger adsorbed the heavy metals from CCA solution. A. niger removed 95% of arsenic, 55% of copper, and 23% of chromium. From these results, A. niger appeared to be useful for the removal of chromium, copper, and arsenic from the end used CCA-treated wood and the use of A. niger-alginate could be effective.

• Journal of the Korean Wood Science and Technology
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• v.33 no.6 s.134
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• pp.101-107
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• 2005

One way of using wood safely and soundly for a long time is use of preservative-treated wood. Although, preservative-treated wood present to us durability and safety during using periods, it is also important to safe disposal after its service periods because of toxic components. Biological methods could be applicable to its disposal methods and better safe than chemical methods in the aspect of environmental problems. This study applied biological methods to remove the heavy metals from end-used CCA treated wood. The Aspergillus niger was used for this study which make black stain on the wood surface by it's spore. This study investigated the growing of A. niger on the CCA treated wood chips and the removal efficiency of heavy metals from CCA treated wood chips using immobilizing A. niger. A. niger could growing on the CCA treated wood chips and A. niger remove the effective elements of CCA treated wood effectively.

• Journal of the Korean Wood Science and Technology
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• v.33 no.3 s.131
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• pp.53-63
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• 2005

This study attempted to obtain the basic data of utilizable possibility of preservative treated wood as a material used in a marine ranch. To evaluate the leaching stability of CCA-, CCFZ-, and ACQ-treated woods in seawater, the specimens treated with 2% and 3% (w/v) of CCA, CCFZ, and ACQ were exposed to deionized water, synthetic seawater and natural seawater for 41 days and then each component released was periodically determined. There was little amount of copper and chromium released from CCA-treated wood exposed in both deionized and seawater. Although relatively large amount of arsenic was released from CCA-treated wood, the release rate in seawater was lower than that in deionized water. The release rate of chromium and zinc from CCFZ-treated wood were somewhat greater in deionized water, but lower in seawater than in deionized water. Retention level and salinity of synthetic seawater had little effect on the release rate of components. The ACQ-treated wood had greater copper release than CCA- and CCFZ-treated wood, and the amount of copper released did not affected by leaching media used.

• Journal of Korea Foresty Energy
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• v.23 no.2
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• pp.29-33
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• 2004

This study was carried out to find out safety disposal methods of waste CCA treated wood. The heavy metals of remnant were analyzed after combustion of CCA treated wood at different temperatures. Arsenic volatilized temperature was detected. The removal rate of heavy metals by acid in the ash were examined. Through this study, we could conclude that in order to protect volatilize arsenic, combustion of CCA treated wood should be do under the $300^{\circ}C$. But when CCA treated wood combustion under $300^{\circ}C$, it's weight-loss rate was $55\%$, so land reclamation dependence will be increased. When CCA treated wood combustion at high temperature, the land reclamation dependence could be reduced, but the arsenic that volatilize into the atmosphere should be captured. When it bums with high temperature, the ash contains lots of copper and chromium, so removal of heavy metals should be conducted.

• Journal of the Korean Wood Science and Technology
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• v.30 no.2
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• pp.151-157
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• 2002

The removing copper from CCA, CCFZ treated wood were tested with Tyromyces palustris. The shacking culture, solid culture, and stationary culture methods were tested to removal of copper in CCA, CCFZ treated wood. The steam pressure method and oxalic acid method were tested as pretreatment. To investigate of copper removal mechanism, the oxalic acid that produced by T. palustris and combination with copper was examined on stationary culture that contained CCA and CCFZ treated wood chips. Oxalic acid increased copper removing rate of T. palustris as pretreatment. Stationary culture had most removal effectiveness among the culturing methods. The removal rate of copper on bioreactor was 61% on 7 days. Copper-oxalate was detected on liquid culture, which show the oxalate from liquid of culture combined with copper from treated wood. It would be related to the removal of copper from treated wood by T. palustris.

• Analytical Science and Technology
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• v.21 no.1
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• pp.1-8
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• 2008

This study was conducted to investigate the characteristics of the leaching of metal components from CCA-treated wood during outdoor exposure. CCA-treated wood specimens were placed horizontally or buried vertically into the soil, and then exposed to the natural environment for a year. Wood samples were collected from the side of the horizontal wood specimens using a drill and saw dust samples were collected at the end of the exposure. Soil samples were also obtained around the wood specimens and at different depths of the posts. Wood and soil samples were analyzed for metals using an atomic absorption spectrometer. Monthly metal concentrations varied greatly and more metals were released when wood specimens were exposed vertically than horizontally. Arsenic was released from the wood by 80 % of the intial content. In addition, more leaching was observed from the zone below the ground than above the ground, and soil around the posts was contaminated with metals released from CCA-treated wood.

• Korean Journal of Environmental Agriculture
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• v.28 no.4
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• pp.340-346
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• 2009

Chromated copper arsenate (CCA) is a chemical wood preservative that has been intensively used to protect wood from decay during the last few decades. CCA is widely used to build structures such as decks, fences, playgrounds and boardwalks. However, structures constructed of CCA-treated wood have caused adverse environmental effects due to leaching of Cr, Cu and As into surrounding soils. This research was conducted to monitor the vertical and horizontal distribution of Cr, Cu and As in soils adjacent to CCA-treated wood structures in Korea. Two structures constructed with CCA-treated wood were selected at Hongcheon and Chuncheon in Gangwon Province, South Korea. Eleven soil profile samples were collected at depths of 0 to 80 cm at each site, while 12 surface soil samples were collected at distances of 0 to 200 cm from each structure. The soil chemical properties, soil particle size distribution and total metal concentrations were then determined. The results revealed that soils near CCA-treated wood structures were generally contaminated with Cr, Cu and As when compared to the background concentration of each metal. In addition, the concentrations of Cr, Cu and As in soils decreased as the vertical and horizontal distance from the structure increased. Further studies should be conducted to evaluate the mobility and distribution of these metals in the environment as well as to develop novel technologies for remediation of CCA contaminated soils.

• Journal of the Korean Wood Science and Technology
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• v.33 no.6 s.134
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• pp.87-94
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• 2005

This study was carried out to investigate the effect of soil types and soil properties on wood preservative leaching. Radiata pine (Pinus radiata Don.) sapwood stakes, which had been treated with 2.0%(w/v) CCA, were leached for 12 weeks by a common laboratory method in four different soils and for 14 days by the AWPA standard leaching method in water. The physical and chemical properties of the four soils were determined, and the percent leaching of the individual component of CCA was correlated with the various soil properties. The data show that leaching of preservative chemicals from treated wood exposed to soil is influenced by the type of soil. The preservative leaching was greater when wood was exposed to water than when the wood was in contact with water-saturated soil. The greatest chromium, copper and arsenic leaching from CCA-treated stakes were observed in the sandy loam, loam, and sand, respectively, and the least amount of leaching of CCA components occurred in the silty loam. The leaching of preservative components from treated wood is extremely complex and appears to be influenced differently by the soil properties. The extent of copper leaching from CCA treated wood appears to be related to exchangeable Mg and sum of bases. There is a reasonably good relationship between chromium leaching and exchangeable Mg, and between arsenic leaching and exchangeable K, soil Ni, Mn, Fe, Cr, or Cu content. Since this study was conducted based on laboratory leaching method using small cross-sectional dimensions; thus, data obtained from this experiment should not be used to predict leaching characteristics from commercial-size wood used in real situation. Accordingly, further studies are necessary using outdoor ground-contact leaching.

• Journal of the Korean Wood Science and Technology
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• v.23 no.4
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• pp.33-38
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• 1995

The rates of fixation of CCA-Type B and CCFZ in blocks of radiata pine sapwood were compared at various temperatures and conditioning methods (drying and nondrying conditioning). Also the time required to proper fixation of preservative components in the treated wood was estimated. Fixation was monitored by the rates of depletion of free hexavalent chromium in the cell lumens in the teated blocks. The rate of preservative fixation in wood was highly temperature dependent. The fixation rate was considerably accelerated by means of heating and complete fixation of hexavalent chromium was achieved within about 12 hours by heating at $60^{\circ}C$. The moisture content of treated wood during fixation apparently played an important role in the fixation process. The fixation rate of treated wood conditioned in nondrying conditions was much more faster than that of treated wood conditioned in drying conditions. particularly when the moisture content of treated wood was below fiber saturation point. Time required to full fixation could be predicted successfully using the fixation temperatures applied since the correlation between the fixation temperature and the fixation time was excellent. regardless of conditioning methods.