Determination of Amount of Cyanide in Pipeline Gas of Fluid Catalytic Cracking Unit in Refinery

A method for the determination of amount of cyanide in pipeline gas of fluid catalytic cracking unit in refinery was proposed. The optimized conditions for the sample collection were as follows:6 mol·L-1 NaOH absorption solution (50 mL) was filled in the first two impingers;CdCO3 was added to the first impinger;volume of the gas collected was no larger than 0.1 m3;velocity of the gas was in the range of 2.0-2.5 L·min-1. The optimized distillation conditions were:100 g·L-1 EDTA-2Na solution (10 mL) was added in distillation flask;40 g·L-1 NaOH solution (10 mL) was added as absorption solution in receiving flask. The proposed method was applied to the absorbed sample,giving values of recovery in the range of 81.7%-92.0%.