Rapid Regeneration of Chelated Iron Desulfurization Solution

CATALYSIS, KINETICS AND REACTION ENGINEERING
Chinese Journal of Chemical Engineering, 22(2) 136—140 (2014)
DOI: 10.1016/S1004-9541(14)60005-7

Rapid Regeneration of Chelated Iron Desulfurization Solution Using
Electrochemical Reactor with Rotating Cylindrical Electrodes*
YU Yong (于永), LIU Youzhi (刘有智)** and QI Guisheng (祁贵生)
Research Center of Shanxi Province for High Gravity Chemical Engineering and Technology, North University of
China, Taiyuan 030051, China
Abstract A new electrochemical reactor with rotating cylindrical electrodes was designed and used to increase the regeneration efficiency of chelated iron desulfurization solution. The influence of operating parameters, such as the rotation speed of electrode, voltage, and inlet air and liquid flow rates, on the regeneration rate was investigated.
Compared with the traditional tank-type reactor, the regeneration rate with the new electrochemical reactor was increased significantly. Under the optimum conditions, the regeneration rate was increased from 45.3% to 84.8%.
Experimental results of continuous operation indicated that the new electrochemical regeneration method had some merits including higher regeneration efficiency, smaller equipment size and good stability in operation.
Keywords regeneration, desulfurization, chelated iron, electrochemistry, reactor

1

INTRODUCTION

H2S is a toxic, malodorous and sour gas emitted from industrial activities such as petroleum refining, pulp and paper manufacturing, food processing, natural gas treating and coal gasification, which leads to severe air pollution and results in great harm to people’s living and production. The removal of H2S has become a very important gas cleanup process in the chemical industry.
Several desulfurization methods, such as dry-, semidry- and wet-processes, have been proposed. The wet desulfurization method is the main technology used [1] due to larger treatment volume, easier recovery of sulfur and more

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