水中痕量苯酚用粒度≤80 μm的活性炭从pH 6左右的介质中吸附富集,并用50 g·L-1氢氧化钠解吸后从pH 4的磷酸溶液中蒸馏分离.分取部分馏出液,在氨性缓冲介质中使苯酚与4-氨基安替比林和铁氰化钾反应生成橙红色络合物,在510 nm波长处对试剂空白测定其吸光度,标准曲线用苯酚标准溶液制备,其线性范围为0.5-12.5 μg(52.5 mL显色液中).方法的检出限为2.9×10-6g·L-1,应用此方法测定了4种水样中的苯酚,相对标准偏差在3.5%-4.7%之间,回收率在92%-107%之间.

Trace amounts of phenol in water were enriched by adsorption on active carbon (graininess ≤80 μm) in an acetate buffer medium of pH 6.The enriched phenol was desorbed from active carbon with 50 g·L-1 NaOH solution.The alkaline solution was adjusted to pH 4 with phosphoric acid,and phenol was separated by distillation.An aliquot of the distillate was taken and reacted with 4-amino-antipyrine and potassium ferricyanide in an ammoniacal buffer to give an orange-reddish colored complex,the absorbance of which was measured at the wavelength of 510 nm using a reagent blank as reference solution.Calibration curve was prepared with standard phenol solutions in the concentration range of 0.5 to 12.5 μg per 52.5 mL of the colored solution.Detection limit of this method was 2.9×10-6g·L-1.In the analysis of 4 water samples for their phenol contents by this method,RSD′s (n=7) found were in the range of 3.5%-4.7%,and recoveries in the range from 92%-107%.