含酚废水中有机酸的气相色谱测定

DETERMINATION OF CARBOXYLIC ACIDS IN WASTEWATER CONTAINING PHENOLS BY GC

本文报导从复杂的高浓度废水,特别是含高浓度酚的废水中分离测定有机酸的气相色谱分析方法。利用有机酸和酚在酸性上的差别,在水溶滚中加入适量的碳酸氢钠,用二氧甲烷萃取,有机酸留在水相,而酚类进入有机相.在水相中的羧酸用乙醚萃取,或经甲醇-硫酸甲酯化处理,得到羧酸酯类化合物,再用乙醚萃取.然后将萃取液进行气相色谱或色-质谱测定。 采用正交设计试验选择了最佳衍生化条件.一元羧酸和二元羧酸衍生化的收率分别为64—98%和60—91％.用本方法检出煤气化废水中的羧酸类化合物四十余种,并进行了定量测定.

Carboxylic acids and phenols in wastewater were separated by extraction with dichloromethane in the presence of sodium bicarbonate. After removal of phenols from the wastewater the aqueous phase was either extracted with ether, or derivatized with CH,OH-HiSO4 followed by extracting the resulting derivatives with ether.In either case,the extract was subjected to GC or GC/MS analysis.Optimum conditions for the derivatization of mono- and di-carboxylic acids were selected, the recovery percentages of derivatization were found to be 64-98% for most monocaboxylic acids and 60-91% for most dicarboxylic acids.By this method, more than forty carboxylic acids were detected in coal gasification wastewater and quantitatively determined.