Studies On Gas-Liquid Equilibrium Of Sulfur Dioxide In Aqueous Poly (Ethylene Glycol) Solutions

By the rapid development of industry, the consumption of sulfur fuel keeps increasing, leading to more and more emission of flue gas and other sulfur exhaust gas. As the main sulfur component of flue gas, the emission of SO₂ brings about serious environment pollution, which may threaten the human health. Therefore, how to remove SO₂ from flue gas has become the focus all over the world.In this work, the recent development of flue gas desulfurization technology was reviewed firstly, in which alcohol-amine method of desulfurization by organic solvent was mainly introduced. Using the gas-liquid equilibrium method, the absorption data of SO₂ in polyethylene glycol-400 (PEG-400) and polyethylene glycol + water system (PEGW) were investigated. And the interaction mechanism between SO₂ and two systems was discussed via spectra analysis. The work was divided into three parts as follows:(1) Density and viscosity were determined over the whole concentration range for the binary mixtures of PEG-400 + water in temperature range of 298.15 K to 323.15 K. The data of pure PEG-400 and water generally agreed with available literature data. These data have been used to compute excess properties of the system. The calculated VmE values for the aqueous PEG-400 solutions were negative at all temperatures and compositions. And the viscosity deviations (Δη) for PEG-400 + water system, were positive at all concentrations and temperatures.(2) Using gas-liquid equilibrium method, the absorption performance of SO₂ in PEG was investigated, and the equilibrium data were determined under 25℃and 122.60 kPa. The interaction mechanism was discussed via spectra analysis The results show that the absorption ability of SO₂ in PEG is charming and this is probably attributed to the hydrogen bonding association between the hydrogen atoms of PEG and the oxygen atoms of SO₂.(3) Using gas-liquid equilibrium method, the absorption capcity of SO₂ in PEGWs under different mas fraction of PEG were investigated. The absorption mechanism of SO₂ in PEGW was discussed via spectra analysis. The results show that when PEGW contains about 85 % polyethylene glycol in mass fraction (namely that the mole ratio of polyethylene glycol and water equals to 1∶4), a kind of special structure may be formed by hydrogen bonding association to result in unfavorable absorption for SO₂ in this PEGW solution.