Analysis And Research Of Ferrocyanide In Coking Wastewater

Coking wastewater contains a certain amount of ferrocyanide. Accurate quantification of ferrocyanide is significant to study the composition of total cyanide and improve the process of desulfurization decyanation. In this paper, three methods are used to determine the content of ferrocyanide in coking wastewater. The methods are applied to the vacuum carbonate desulfurization wastewater and obtain certain results.In acidic medium, the potassium ferrocyanide and divalent iron ions react and generate Prussian blue. This article measures by spectrophotometry. The method is accurate and convenient. When the concentration of potassium ferrocyanide is2-22mg/L, the relationship between the absorbance and the concentration of potassium ferrocyanide is linearly related. Linear regression equation is A=0.0294C(mg/L)-0.0018. Correlation coefficient is0.9997. Molar absorptivity is12.4×103L· mol-1· cm-1. The detection limit is0.3mg/L.In acidic medium, this article use zinc sulfate standard solution and potassium ferricyanide solution together to titrate potassium ferrocyanide and use diphenylamine as an indicator. End point is indicated by color change. The method is simple, and eliminates the complex experimental apparatus. This method applies to the determination which needs less precision.Through the further improvement of the ordinary titration, this article chooses potentiometric titration to accurately determine the content of potassium ferrocyanide. The method has been successfully used for some sample determination which needs high precision. In addition, in potentiometric titration data processing, this article uses the C++computer language to realize the intelligent calculation of titration endpoint. It improves the accuracy of the method.In the three methods described above, optimal experimental conditions and miscellaneous ion impact of the various methods are investigated. And this article tests analog samples to verify the feasibility of the method under optimal conditions. The relative standard deviation of the actual sample by the three methods is between0.83%and4.27%. Coefficient of recovery is between95.36%and107.73%.This article finds different methods for determination of ferrocyanide through the analysis and study of the characteristics of ferrocyanide In order to provide a theoretical basis for the the coking wastewater...