Abstract:The aim of this study is to solve the problem of the difficulty of accurate detection of CN- and SCN- due to the interference of multiple ions in the wastewater produced by coke oven gas desulfurization. To this end, based on the basic principles of analytical chemistry and elimination of inter-ionic interferences, this paper proposes a conventional inorganic chemical analytical method for the detection of CN-, SCN- in the alkaline wastewater generated from coking gas desulfurization by vacuum potassium carbonate method, including a pretreatment method and an instrumental detection step. Among them, the elimination of SCN-, S2-, SO32- and S2O32- from the interference of silver nitrate volumetric method on CN- was realized by the pretreatment method of the first acidification and distillation, and the second precipitation with distillation, and then the concentration of CN- was determined by silver nitrate volumetric method. The elimination of the interference of CN-, S2- and phenol on SCN- detection by precipitation, extraction and coordinated pretreatment methods is realized, on the basis of which SCN- is then determined spectrophotometrically using ferric thiocyanate. More explicit detection steps and discussion of influencing factors are also given, and the method can be used for the detection of CN- and SCN- in complex environmental samples, providing better technical support for the control of coke oven barren gas desulfurization process and wastewater treatment.