氯仿萃取法消除氰化物测定中的油干扰

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。

Elimination of grease disturbance in cyanide determination by chloroform extraction

The wastewater from gum benzion production contains benzaldehyde, cyanide, gum benzoin and ethyl benzoate. When the cyanide is determined by iso nicotinic acid pyrazalon method, the ethyl benzoate is distilled and goes into NaOH absorption liquid with cyanide in the process of pre distillation, because its 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 grease and water, chloroform extraction is used to remove the grease. Then the cyanide in water can be determined. Experiments show that this method has ideal unanimity, less errors, and high recurrence rate. It is an effective way to eliminate organic grease disturbance.