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

基于铜胺的木材防腐剂，如碱性铜季铵化合物（ACQ），已被临时注册为消费者和住宅用途的铬酸铜砷酸盐的替代品。关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浸出抗性的加工变量，人们知之甚少。本研究旨在探讨铜胺防腐剂中铜及季铵化合物成分在木材中的固定机理，并借由分析铜在木材中的形态变化及对木材化学性质的影响。将评估温度、相对湿度、溶液浓度和木材种类等加工变量对组分稳定化速率和程度的影响。 由于质量控制程序对确保经处理的木材经过最佳稳定化处理的重要性，将制定和评价在处理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中防腐剂成分沥滤的影响，并将评价扩散模型预测木材在沥滤条件下有机和无机成分排放的能力。将调查通过从废木材中化学提取有效成分作为一种潜在的再循环办法来补救已处理的废弃木材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.