Efficient and Reversible Absorption of Sulfur Dioxide of Flue Gas by Environmentally Benign and Stable Quaternary Ammonium Inner Salts in Aqueous Solutions

详细信息    查看全文

• 作者：Kai Zhang ; Shuhang Ren ; Lingyuan Meng ; Yucui Hou ; Weize WuYuyun Bao
• 刊名：Energy & Fuels
• 出版年：2017
• 出版时间：February 16, 2017
• 年：2017
• 卷：31
• 期：2
• 页码：1786-1792
• 全文大小：436K
• ISSN：1520-5029

文摘

Novel kinds of environmentally benign and stable absorbents, quaternary ammonium inner salts betaine (Bet) and l-carnitine (l-car) in aqueous solution, were designed and applied to efficiently and reversibly capture sulfur dioxide (SO₂) in flue gas. The effects of the inner salt concentration, absorption temperature, SO₂ concentration, and reuse cycle on the absorption of SO₂ by the two absorbents were investigated. The results show that SO₂ absorption capacities of the absorbents with 50% inner salt mass fraction were 0.155 mol of SO₂/mol of Bet for Bet aqueous solutions and 0.599 mol of SO₂/mol of l-car for l-car aqueous solutions, at 40 °C with a SO₂ concentration of 2%, and the absorption capacities of absorbents did not change after 5 absorption/desorption cycles. Furthermore, Fourier transform infrared spectroscopy and proton nuclear magnetic resonance results demonstrate that the SO₂ absorption follows the law that a strong acid (H₂SO₃) replaces a weak acid (−COOH). The absorbents could be used for more than 1 week without any change in the structure, indicating the promise for industrial applications in desulfurization of flue gas.