焦炉煤气脱硫废液中CN^(-)、SCN^(-)的测定  

Determination of CN^(-) and SCN^(-) in Coke Oven Gas Desulfurization Waste Liquid

作　　者：刘钲楠 付本全[2] 胡辉[1] 曾为一 王丽娜 黄浩 LIU Zhengnan;FU Benquan;HU Hui;ZENG Weiyi;WANG Lina;HUANG Hao(College of Environmental Science and Engineering,Huazhong University of Science&Technology,Wuhan,Hubei 430074,China;Wuhan Iron and Steel Research Institute,Wuhan,Hubei 430080,China)

机构地区：[1]华中科技大学环境科学与工程学院,武汉430074 [2]武汉钢铁(集团公司)研究院,武汉430080

出　　处：《中国无机分析化学》2024年第10期1369-1377,共9页Chinese Journal of Inorganic Analytical Chemistry

基　　金：湖北省技术创新专项项目(2019ACA158)。

摘　　要：为解决焦炉煤气脱硫产生的废水中多种离子干扰导致CN^(-)、SCN^(-)难以准确检测问题,基于分析化学和消除离子间干扰的基本原理,提出常规无机化学分析方法检测真空碳酸钾法焦化煤气脱硫产生的碱性废液中CN^(-)、SCN^(-),包括预处理方法和仪器检测步骤。其中,易释放氰化物通过第一次酸化蒸馏,第二次沉淀配合蒸馏的预处理方法实现了消除SCN^(-)、S^(2-)、SO_(3)^(2-)和S_(2)O_(3)^(2-)对硝酸银容量法检测CN^(-)过程中的干扰,再利用硝酸银容量法测定CN^(-)浓度。利用沉淀、萃取和配合的预处理方法实现CN^(-)、S^(2-)和苯酚对SCN^(-)检测干扰的消除,在此基础上再利用硫氰酸铁分光光度法测定SCN^(-)。还给出了更明确的检测步骤和影响因素讨论,方法可用于复杂环境样品中CN^(-)、SCN^(-)的检测,为焦炉荒煤气脱硫过程控制和废水处理提供更好的技术支持。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 proposed 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 pretreatment method and instrumental detection step.Among them,the elimination of SCN^(-),S^(2-),SO_(3)^(2-) and S_(2)O_(3)^(2-) 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^(-),S^(2-) and phenol on SCN^(-) detection by precipitation,extraction and coordinated pretreatment methods was realized,on the basis of which SCN^(-) was then determined spectrophotometrically by ferric thiocyanate.More explicit detection steps and discussion of influencing factors were also given.The method can be used for the detection of CN^(-) and SCN^(-) in complex environmental samples,which will provide better technical support for the control of coke oven barren gas desulfurization process and wastewater treatment.

关 键 词：氰根 硫氰酸根 干扰 荒煤气 脱硫废液 

分 类 号：O657.31[理学—分析化学] X132[理学—化学]