• 作者： 楊秋忠
• 作者服務機構： 國立中興大學土壤研究所
• 中文摘要： 欲從理化特性複雜的土壤中萃取存在極小量的農藥是非常困難的工作，而傳統的萃取方法手續煩長費時，又不適合大取樣數之分析，為了改進其缺點，本研究採用新的構想，利用Amberlite XAD-4樹脂萃取回收土壤中氯苯氧殺草劑，並研究尋求最有效之萃取手續及促進回收之方法。 試驗結果以樹脂與土壤混合，並調整pH至8.5及加入NaCl萃取2小時，再經浮取法分離出樹脂之回收氯苯氧殺草劑（2，4-D，2，4，5-及α，2，4，5-TP）為最佳。加NaCl增進過濾法之回收率，但對浮取法之增進則無顯著差異。增加pH值至8.5有助回收率，pH 8.5與pH 11之處理對回收率無顯著差異。殺草劑加入後不等的時間（2小時至7天）對樹脂法之萃取並無限制。台中砂頁岩沖積土及屏東枯板岩沖積土利用樹脂萃取法之回收率並無差異。2，4，5T及 α，2，4，5TP利用樹脂萃取法之回收率比傳統之酸－乙醚萃取法高出11－18％；2，4-D則較低，以88.7％對93.4％。由結果顯示利用樹脂萃取氯苯氧殺草劑是有效及簡便之方怯。
• 英文摘要： Herbicides play an important role in modern agriculture. To extract and determine a small quantityof herbicide in the soil, which is invariably a highly complicated chemical and physical entity, has alwaysbeen a difficult task. Recovery of herbicide applied to the soil by. conventional methods is usually timeconsuming. A new approach using Amberlite XAD-4 resin to extract chlorophenoxy herbicides from soilis tried in this study. The results showed that XAD-4 resin mixed with a soil sample and sodium chloride at pH 8.5 condi-tion for two hours extraction, and using the floatation method to separate the resin and the soil gave thehighest recovery of three chlorophenoxy herbicides (2,4-D, 2,4,5-T, and α,2,4,5-TP). The addition ofNaCl to the XAD-4 extraction increased the recovery of these herbicides by the filtration method, but notby the floatation method. The recovery of chlorophenoxy herbicides increased with the increasing pH ofextraction. However, there was no significant difference between pH 8.5 and pH 11 treatments. Therewas also no significant difference in the recovery of these herbicides by XAD-4 extraction between Taichungsandstone-shale alluvial soil and Pingtung slate alluvial soil. The recoveries of 2,4,5-T and α,2,4,5-TP by thenew method, except 2,4-D, were greater by 11-18％ than that by the conventional acid-ether extractionmethod. The recoveries of 2,4-D were 88.7％and 93.4％in the XAD-4 extraction and the acid-ether extrac-tion, respectively. The resin extraction is a reliable and quick method to recover chlorophenoxy herbicidesfrom soils.
• 中文關鍵字： amberlite XAD-4; chlorinated phenoxyalkanoic acids; herbicides; resin extraction; soil extraction; 2;4-D; 2;4;5-T; α;2;4;
• 英文關鍵字： --