高压消解—ICP-AES测定木材及木制品中的铜铬砷

研究了木材及木制品的制备，样品被制成锯末，过孔径为0.5mm的筛，在105℃烘干4～5 h，采用方差分析法进行样品均匀性试验。比较了湿法、干法、高压消解(包括密闭微波消解系统和钢衬聚四氟乙烯消解罐消解)样品的前处理方法。从比较结果来看，湿法消解适用于测定样品中可溶性的铜铬砷，干法消解和高压消解适用于测定样品中总的铜铬砷，但干法消解使砷有挥发损失。探讨了酸度效应和基体效应。建立了高压消解—ICP-AES测定木材及木制品中铜铬砷总量的方法。铜铬砷的检出限(3σ)分别为：1.2，0.2，7.1 mg·kg-1,相对标准偏差为0.2％～1.5％，回收率为92％～106％。该方法为控制木材、木制品及其废弃物中有害物质提供了更为合理的结果，已应用于实际的检测工作。

Determination of Copper, Chromium and Arsenic in Wood and Its Products by High Pressure Digest-ICP-AES

Sample preparation was studied, samples were sawn to be sawdust, screened by a 35 mesh sieve, dryed 4-5 h at 105 degrees C, and its homogeneity was tested by variance analysis. Sample pretreatment methods were investigated with wet decomposition, dry ashing, high pressure digest (including microwave-assisted closed digestion and steel liner PTFE vessel digestion). According to the comparative results, wet decomposition is fit for testing soluble copper, chromium and arsenic. Dry ashing and high pressure digest are fit for testing total copper, chromium and arsenic, but arsenic is easy to lose in dry ashing. Acidity effect and matrix effect were discussed. A method was proposed for the determination of total copper, chromium and arsenic in wood and its products by high pressure digest-ICP-AES. The detection limit of copper, chromium and arsenic was 1.2, 0.2 and 7.1 mg x kg(-1), respectively, RSDs were in the range of 0.2%-1.5%, and recoveries were between 92% and 106%. Using this method, more reasonable results will be given for controlling toxic substances from wood and its products and their wastes. This method has been applied to practical sample analysis.