The new copper-based preservative systems leach a relatively high level of copper and, thus, generate some environmental concerns. Polyvinyl alcohol (PVOH) is known to complex with copper(II) and is water soluble. The effect of co-addition of fully hydrolyzed PVOH on the leaching of copper from wood treated with three different copper salts was examined. Southern pine sapwood wafers were treated with copper sulfate, copper acetate, and ammoniacal copper carbonate, all with 1 percent elemental copper in the waterborne solution, with and without 2 percent PVOH. The wafers were then dried and water leached for 2 weeks. PVOH co-addition greatly reduced the copper leached from wood treated with alkaline ammoniacal copper carbonate but not from wood treated with a slightly acidic solution of copper acetate or highly acidic copper sulfate.
Contributor Notes
The authors are, respectively, Former Graduate Research Assistant and Professor, Forest Products Lab./FWRC, Mississippi State Univ., Mississippi State (dnicholas@cfr.msstate.edu); Professor, Dept. of Chemistry, Mississippi State Univ., Mississippi State (wph1@ra.msstate.edu); and Professor, Forest Products Lab./FWRC, Mississippi State Univ., Mississippi State (tschultz@cfr.msstate.edu). Approved for publication as Journal Article no. FP528 of the Forest and Wildlife Research Center, Mississippi State University. This paper was received for publication in April 2009. Article no. 10607.
*Forest Products Society member.