有机化工产品安息香生产废水中含有苯甲醛、氰化物、安息香和苯甲酸乙酯,在用异烟酸吡唑啉酮法对其进行氰化物测定时,由于油酯类的沸点较低,在预蒸馏过程中被蒸出和氰化物一起进入NaOH吸收液,使得吸收液产生大量泡沫和沉淀,严重干扰后续比色测定。作者采用氯仿萃取法对废水进行除油处理,使油水分离,再测定水中的氰化物,实验表明该方法重复性好,相对误差小、一致性好,是一条有效的消除油类有机物干扰的途径。

The w astew ater from gum benzion production contains benzaldehyde, cyanide, gum benzoin and ethyl benzoate.When the cy anide is determined by iso-nicotinic acid-py razalon method, the ethyl benzoate is distilled and goes into NaOH abso rptio n liquid w ith cy anide in the process of pre-distillation, because it s boiling point is low.Thus the absorption liquid produces a great deal of foam and feculence.This disturbs the sequent colorimetric determination seriously.To separate the g rease and water, chloroform ex t raction is used to remove the grease.Then the cyanide in w ater can be determined.Experiments show that this method has ideal unanimity,less errors, and high recurrence rate.It is an effective w ay to eliminate organic g rease disturbance.