Efficacy of Pentachlorophenol in Biodiesel versus Diesel

Pentachlorophenol (PCP) is widely used as a wood preservative for utility poles and other wood products. It has been proposed that a modified PCP carrier system based on a diesel/biodiesel mixture should be used in place of the conventional diesel/KB3 carrier, but questions exist as to whether this modified carrier system can provide the same service life as wood products treated with PCP/diesel/KB3. The main objective of this research was to evaluate the comparative decay resistance of wood treated with carrier formulations containing either diesel/KB3 or diesel/biodiesel. A 2-year efficacy study using an accelerated soil contact decay test was initiated to compare the performance of southern yellow pine wood treated with the conventional diesel/KB3 carrier and a modified diesel/biodiesel carrier, both with and without PCP. The residual hydrocarbon levels, PCP reduction, toxicity, and leaching of PCP of the samples remained approximately at the same level for treatments with similar PCP retentio...