On-Line Sorting of Wood Treated with Chromated Copper Arsenate Using Laser-Induced Breakdown Spectroscopy

Abstract

This paper details the design, implementation, and field evaluation of an online detector system using laser-induced breakdown spectroscopy (LIBS) for the analysis of copper chromated arsenate (CCA) treated wood products. The LIBS-based instrument functioned by creating the laser-induced plasma directly on the sample surface while wood was translated under the detector system, and was successful in discriminating between CCA treated wood and untreated wood products based on the atomic emission signal of chromium. The system was optimized for plasma emission collection both in and out of the laser focal plane and temporally optimized for chromium analysis using a compact, non-intensified charge-coupled device (CCD)/spectrometer unit. Using either single laser pulse spectra or 5-shot and 10-shot spectral averages, the accuracy of LIBS-based analysis ranged from 92 to 100% for identifying both CCA treated and untreated wood samples from the waste stream at a construction and demolition debris recycling center. Additional implementation issues are discussed in the context of LIBS-based on-line sorting of construction and demolition wood debris.

Multivariate analysis of laser-induced breakdown spectroscopy chemical signatures for geomaterial classification

“…LIBS is an emerging technology for real-time chemical analysis that has found application in a variety of industrial [1][2][3][4][5], cultural [6][7] and security [8][9][10][11] applications and presently is under development for extraterrestrial exploration [12][13][14]. Over the past two decades, there have been a variety of applications of LIBS to geological materials, mostly focused on quantitative determination of a few elements [15][16][17][18][19][20][21][22][23][24][25].…”

Applications of High Resolution Laser: Induced Breakdown Spectroscopy for Environmental and Biological Samples

“…Another application that is of great interest to plant and forestry scientists is the chemistry of wood response to precipitation and forest fires that occur naturally in the environment or controlled fire events. The housing industry is very much interested in sorting preservative treated wood [21,[60][61][62]. The authors have shown that LIBS has practical applications in recycling facilities and on building sites.…”

Wood production, wood technology, and biotechnological impacts

“…Other newer developments concentrate on sophisticated techniques for sorting the contaminated material from acceptable wood waste. X-ray fluorescence spectroscopy (XFR) and laser-induced breakdown spectroscopy (LIBS) are promising detector technologies to identify CCA (chromated copperarsenate)-treated wood and CCA-containing paints on wood, and also other types of preservatives (Peek 1998, Peylo & Peek 1998, Uhl et al 2001, Blassino et al 2002, Moskal & Hahn 2002, Solo-Gabriele et al 2004, Block et al 2007, Dubey et al 2007). …”