Optimizing processes and performance of chromium- and arsenic-free wood preservatives

铜胺类木材防腐剂，如碱性铜季铵化合物(ACQ)，已获得临时注册，作为消费和住宅用途的铬化砷酸铜的替代品。对于这些防腐剂在木材中的固定或稳定的基本模式，以及在处理厂和使用中提高防腐剂抗浸出性的工艺变量，人们知之甚少。本课题通过研究稳定化铜的形态及其对木材化学的影响，探讨了铜及铜胺类防腐剂季铵化合物组分在木材中的基本固定机理。将评估加工变量，如温度、相对湿度、溶液浓度和木材种类对成分稳定化的速度和程度的影响。由于质量控制程序对于确保处理过的木材进行最佳稳定化处理的重要性，将开发和评估在处理工厂评估稳定化程度的方法。将评估稳定化程序对使用中木材防腐剂成分淋失的影响，并将评估扩散模型预测木材在淋溶条件下有机和无机成分排放的能力。将研究通过从废旧木材中化学提取活性成分来修复处理后的木材作为一种潜在的回收选择的经济和技术可行性。

Copper amine based wood preservatives such as alkaline copper quaternary ammonium compound (ACQ) have been given temporary registration as alternatives to chromated copper arsenate for consumer and residential uses. Relatively little is known about the fundamental mode of fixation or stabilization of these preservatives in wood and on processing variables that result in improved resistance to preservative leaching at the treating plant and in service. This project investigates the fundamental fixation mechanism of copper and quaternary ammonium compound components of copper amine preservatives in wood, by examining the speciation of stabilized copper and the changes to the wood chemistry. Effects of processing variables such as temperature, RH, solution concentration and wood species on rate and extent of stabilization of components will be evaluated.  Because of the importance of quality control procedures to ensure that the treated wood has been processed for optimal stabilization, methods of assessing degree of stabilization at the treating plant will be developed and evaluated. Implications of stabilization procedures on leaching of preservative components from wood in service will be assessed and diffusion models will be evaluated for their ability to predict emissions of both organic and inorganic components from wood when exposed to leaching conditions. The economic and technical feasibility of remediating treated wood removed from service by chemical extraction of active ingredients from spent wood as a potential recycling option will be investigated.