Soil cyanide and total cyanide-Determination of isonicotinic acid-pyrazolone spectrophotometric method (2)

Four, instruments and equipment

(1) Analytical balance: precision 0.

(2) Spectrophotometer: with 10nm cuvette

(3) Constant temperature water bath

(4) Electric furnace

(5) All-glass distiller, including round bottom distillation flask and serpentine condenser

(6) 100mL colorimetric tube with stopper

(7) 25mL colorimetric tube with stopper

(8) 250mL graduated cylinder

(9) 100mL volumetric flask

(10) Commonly used instruments and equipment in general laboratories

5.

(1) Collection and preservation

Collect soil samples in accordance with the relevant regulations of HJ/T166.

(2) Determination of dry matter content

According to the relevant regulations of HJ613, the soil sample is baked to constant weight at 105℃±5℃, and the dry matter and moisture content are calculated based on the difference in soil quality before and after drying

(3) Cyanide sample preparation

Weigh about 10g of dry weight sample (accurate to 0.

(4) Preparation of total cyanide sample

Weigh about 10g of dry weight sample (accurate to 0.