학술논문

Understanding the Competitive Gas Absorption of CO2and SO2in Superbase Ionic Liquids
Document Type
Article
Source
Industrial & Engineering Chemistry Research; November 2018, Vol. 57 Issue: 50 p17033-17042, 10p
Subject
Language
ISSN
08885885; 15205045
Abstract
During this work, an original study of the CO2and SO2competitive gas absorption in three superbase ionic liquids (ILs), namely, trihexyltetradecylphosphonium 1,2,4-triazolide ([P66614][124Triz]), and trihexyltetradecylphoshonium benzimidazolide ([P66614][Benzim]), is reported for the first time. To initiate such a comprehensive study, the CO2and SO2mixed gas solubility in selected ILs was determined by using an original and accurate dynamic method coupled with mass spectrometry after several absorption and desorption cycles. This method has been validated by comparing the gravimetric uptake of CO2with the mass spectrometry data using trihexyltetradecylphosphonium benzotriazolide, 1,2,4-triazolide, and benzimidazolide ILs and shown to be consistent within 10% in mole ratio units. Solubility results clearly show that the presence of SO2in the gas stream decreases the CO2capture capability of the investigated ILs. Furthermore, the viscosity, chemical analysis (water content and sulfur content), and spectroscopic data (1H NMR, 13C NMR, attenuated total reflectance-infrared, and X-ray photoelectron spectroscopy) changes before and after absorption–desorption of the gases were determined and depicted to truly understand the reaction mechanism that occurs in the liquid phase, highlighting a clear competition between the SO2versus CO2chemical reaction and selected superbase ILs.