1. Xinan Zhang
Research Assistant
Louisiana Forest Products Development Center
School of Renewable Natural Resources
Louisiana State University
FPS 65th International Conference

2. Introduction
 Chromate Copper Arsenate (CCA)
-- an inorganic waterborne wood preservative
 There was a rapid expansion of the use of CCA
wood preservative between 1975 and 1990, as a
result of high consumer acceptance of the product
for decks, fences and other residential applications
and industrial products such as poles, timbers and
marine piling.

3. Introduction
 The US and Canadian wood preservation industry voluntarily
withdraw the use of CCA treated wood for residential uses on
January 1, 2004
 Currently, most of the out-of-service treated wood ends up in
landfills.
(diffusion into soil and ground water?)
 It is estimated that CCA-treated wood being removed from service
annually in the US would increase to 16x106 m3 by 2020 (Copper
1993).

4. Introduction
Management of spent treated wood products
To recycle spent CCA treated wood
 (1) Burning (diffusion into air ?)
 (2) Reuse to make composites
 (3) Biological detoxification
 (4) Chemical extraction prior to disposal or recycling

5. Literature Review
 Kartal et al. (2008) evaluated the effects of various
adsorbents (activated carbon, Sugi wood charcoal)
from industrial and agricultural process in removal of
Cu, Cr, As from CCA treated wood by using bath
extracting experiments.
 Kartal and Imamura (2005) found that exposing 3g
CCA-treated sawdust to a 200 ml solution containing
2.5 g chitin (biopolymer) for 10 days removed 74%
Cu, 62% Cr and 63% As.

6. Literature Review
 Extraction with 1% ethylenediaminetetracetic acid (EDTA)
solution for 24 h of sawdust samples results in 93% Cu, 36%
Cr and 38% As removal (Kartal, S. N. 2003).
 CCA treated wood can be decontaminated to a high degree by
10% aqueous hydrogen peroxide (H2O2) at 50℃ water bath
and 6h. 95% Cr, 94% Cu, 98% As were removed. (Kazi and
Cooper 2006).
 Clausen and Smith (1998) found that extraction with oxalic
acid as a precursor to bacterial fermentation with B.
licheniformis CC01 removed 90% Cu, 80% Cr and 100% As
from treated chips.

7. Literature Review
Kazi and Cooper (2002) extracted CCA from sludge in
three stages,
 (1) simultaneous extraction and oxidation by
aqueous sodium hypochlorite (5.25%), 2h, 100℃,
R:S 100 recover 51%
 (2) extraction of the remaining CCA salts by
phosphoric acid (2.5%) rest components were
removed after 2h, 100℃ and R:S 100
 (3) oxidation of phosphoric acid leachate by aqueous
sodium hypochlorite (5.25%).

8. Key point
Treatment time
Cost – chemical

9. Objective
 Evaluate the effect of acid extraction microwave
treatment
 Investigate the possibility of reusing the soaking
solution
 Evaluation of antifungal activities of recycled
soaking solution against white-rot and brown-rot
fungi

10. Material and Method
Wood particles preparation
cut into small
a piece of retired utility
pieces
pole
ground in a Wiley Mill
air dried
The wood particles which passed the 40-mesh sieve were
collected

11. Material and Method
 Acid preparation
1:1 acetic acid
phosphoric acid
2.75% 0.75%
mixed acids

12. Material and Method
 microwave extraction
1 g CCA-treated vs 20 ml acids
waste wood particle
 microwave reactor (Milestone, Sheton, CT)
treatment time temperature
20 min 145℃.

13. Material and Method
 Reuse extraction liquids
microwave vaccum filter the collect extraction measure the
treatment extraction liquid Ⅰ liquid Ⅰ volume
made up lost volume by fresh analysis of CCA
A new batch of wood
mixed acids to obtain the concentration
powder was added to
cycle 2 acids
cycle 2 acids
microwave vaccum filter the collect extraction measure the
treatment extraction liquid Ⅱ liquid Ⅱ volume
made up lost volume by fresh
…….. mixed acids to obtain the analysis of CCA
cycle 3 acids concentration

14. Material and Method
 Determination of copper, chromium and arsenic
concentrations
rinse wood residue 1 g wood residue and 15
oven dried
of each cycle with ml nitric acid was mixed
deionized (DI) water in a 100 ml test tube
obtain a transparent
liquid, heat to a
volume of 1 ml, slowly warmed and
Quantitative
transfer into a 25 ml maintain temperature
elemental analysis of
volumetric flask and at120 ℃
copper, chromium
diluted into 25 ml
and arsenic
solution with distilled
water

15. Material and Method
 Evaluation of antifungal activities against white-rot (
Trametes versicolor) and brown-rot fungi
(Gloeophyllum trabeum)
malt extract medium
-- 2% malt extract, 1.5% agar and 0.005% yeast extract
extraction liquid 1
--mixed into 100 ml media to make a series of solutions with different
concentrations

16. Material and Method
Where D2 is the diameter growth in the control dishes and D1 is
diameter growth in the experimental Petri dishes with extract liquids.
The estimation of antifungal activities was carried out with repetition.

17. Result and discussion
1000
900
800
As
Concentration (mg L-1)
700
600
Cr
500
400
Cu
300
200
100
0
1 2 3 4 5 6 7 8 9 10 11 12
Cycle
Fig. 1. The concentration of Arsenic (As), Chromium (Cr) and Copper (Cu) in each
extraction liquid of each cycle (unit: ppm)

18. Result and discussion
100
90
80
70
Recovery rate (%)
60
50 AS
Cr
40
Cu
30
20
10
0
1 2 3 4
Extraction cycle
Fig. 2. The recovery rate of Arsenic (As), Chromium (Cr) and Copper (Cu) in wood
residue from first 4 cycle

19. Result and discussion
Table 1. The everyday fungal growth rate of TV
concentration day
(mg L-1) 2 3 4 5 7 8 9
control 1.65 2.45 3.5 4.5 6.6 7.55 8.7
1.92 1.1 1.8 2.5 3.2 4.7 5.65 6.3
2.53 1 1.7 2.2 2.8 4.1 4.8 5.4
2.84 0.95 1.5 1.9 2.5 3.7 4.4 5
3.15 0.95 1.4 1.8 2.4 3.45 4 4.5
3.45 0.8 1.2 1.55 2 2.95 3.45 3.8
3.76 0.65 1.05 1.45 1.9 2.65 3.2 3.6
4.06 - 0.805 1 1.2 1.7 2 2.2
4.36 - - 0.7 0.9 1.3 1.5 1.65
4.66 - - - 0.65 0.85 1 1.1
4.96 - - - - 0.8 0.9 0.975
5.55 - - - - - - 0

20. Result and discussion
Table 2. The everyday fungal growth rate of GT
concentration day
(mg L-1) 2 3 4 5 7 8 9 10 12 14 16 18 19
control 1.25 1.90 2.60 2.85 3.85 4.35 4.90 5.30 6.15 6.90 7.40 7.80 8.70
1.92 0.88 1.25 1.70 2.05 2.85 3.25 3.60 3.95 4.65 5.10 5.65 6.00 6.25
2.53 0.75 1.05 1.30 1.68 2.20 2.50 2.80 3.10 3.65 4.00 4.55 4.80 5.05
2.84 0.73 1.00 1.30 1.60 2.10 2.45 2.70 3.00 3.45 3.90 4.40 4.70 4.85
3.15 0.65 0.90 1.10 1.40 1.90 2.20 2.40 2.70 3.10 3.60 4.00 4.25 4.55
3.45 0.70 0.90 1.10 1.40 1.80 2.10 2.30 2.60 2.95 3.30 3.70 3.95 4.15
3.76 - 0.70 0.90 1.00 1.55 1.75 1.95 2.10 2.45 2.85 3.30 3.50 3.75
4.06 - 0.80 1.00 1.20 1.60 1.75 1.95 2.10 2.45 2.75 3.10 3.30 3.45
4.36 - - 0.80 0.95 1.20 1.40 1.50 1.75 2.00 2.25 2.50 2.70 2.80
4.66 - - 0.70 0.80 1.00 1.20 1.30 1.40 1.70 1.90 2.05 2.20 2.35
4.96 - - - 0.80 1.00 1.15 1.30 1.40 1.60 1.80 2.00 2.10 2.30
5.55 - - - 0.65 0.80 0.90 1.00 1.10 1.30 1.50 1.75 1.90 2.00
6.14 - - - - 0.65 0.75 0.85 0.95 1.15 1.40 1.60 1.80 1.90
7.3 - - - - - - - - - - - - 0

21. Result and discussion
Fig. 3. Antifungal effects of cycle 1 extraction liquid from different concentration (white rot fungi)

22. Result and discussion
Fig. 4. Antifungal effects of cycle 1 extraction liquid from different concentration brown rot fungi)

23. Result and discussion
100
90
80
Anti fungal index (%)
70
60
50
TV
40 GT
30
20
10
0
1.92 2.53 2.84 3.15 3.45 3.76 4.06 4.36 4.66 4.96 5.55 6.14 7.30 9.55 11.72
Copper concentration in medium (mg L-1)
Fig. 5. Plots of antifungal index (AI) versus copper concentration

24. Summary
 Acid extraction microwave treatment is a fast and
effective method to remove Cu, Cr and As from
CCA-treated waste wood.
 Soaking solution has the potential to continue
remove Cu, Cr and As from CCA-treated waste
wood.
 Soaking solution showed the antifungal activities
against white-rot and brown-rot fungi.

25. Thank you