间接电解硫化氢新体系的研究

Research on a new system of indirect electrolytic hydrogen sulfide

关键词:  H₂S  间接电解  氢气  脱硫速率  电解效率

Key words:  hydrogen sulfide  indirect electrolysis  hydrogen  desulfurization rate  electrolytic efficiency

摘要:

在间接电解硫化氢(H₂S)新体系中,采用EDTA-Fe(Ⅲ)吸收液对H₂S进行吸收处理,将反应后的吸收液进行电解再生。考察了吸收剂质量分数、H₂S摩尔分数、吸收液pH值对脱硫速率的影响、不同电极对电解再生反应的影响及阴阳极再生过程中的电流效率。结果 表明:在吸收阶段,H₂S含量及吸收液pH值的升高使脱硫速率加快；在电解阶段,EDTA-Fe(Ⅱ)在电解电势大于-0.2 V时,氧化电流随电极电势增加快速上升,在石墨电极的电解再生体系下,阳极反应EDTA-Fe(Ⅱ)氧化为EDTA-Fe(Ⅲ)的电流效率随电极电势增加而增加,阴极为高纯度氢气。新体系兼有湿法吸收对H₂S的高吸收率,同时在吸收液再生时回收了氢资源,具有H₂S污染处理及高资源回收率的双重效果。 

Abstract:

In the new system of indirect electrolytic hydrogen sulfide, EDTA-Fe (Ⅲ) absorption liquid was used to absorb hydrogen sulfide, and the reaction absorption liquid was electrolytically regenerated. The effects of absorbent mass fraction, hydrogen sulfide molar fraction, and pH value of absorption liquid on the desulfurization rate, the effects of different electrodes on the electrolytic regeneration reaction, and the current efficiency of during cathode and anode regeneration were investigated. The results showed that at the absorption phase,the desulfurization rate increased with the raising of the content of hydrogen sulfide and the pH value of the absorption solution. At the electrolysis stage, when the electrolytic potential of EDTA-Fe (Ⅱ) was greater than -0.2 V vs SCE, the oxidation current rose rapidly with the increase of the electrode potential. Under the electrolytic regeneration system of graphite electrodes, the current efficiency of the anode reaction of EDTA-Fe(Ⅱ) to EDTA-Fe(Ⅲ) increased with the increase of electrode potential, and the cathode was high-purity hydrogen. The new system combines high absorption rate of hydrogen sulfide by wet absorption with recovering the hydrogen resources during the regeneration of the absorption liquid. It has the dual effects of hydrogen sulfide pollution treatment and high resource recovery rate.