Kinetics of Thermal Regeneration of SO2-Captured V2O5/AC

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• 作者：Daojun Zhang ; Leiming Ji ; Zhenyu Liu ; Qingya Liu
• 刊名：Industrial & Engineering Chemistry Research
• 出版年：2015
• 出版时间：September 30, 2015
• 年：2015
• 卷：54
• 期：38
• 页码：9289-9295
• 全文大小：372K
• ISSN：1520-5045

文摘

Carbon-based materials have been used for SO₂ removal from flue gases for several decades. In this process, SO₂ is captured by storing in the pores of carbons in the form of H₂SO₄, and regeneration of the SO₂-captured materials is necessary to recover SO₂ capture ability. V₂O₅-supported activated coke (V₂O₅/AC) has been reported to be highly active for SO₂ removal, and its regeneration has been investigated from the viewpoint of the reaction mechanism. This work studied the regeneration kinetics with the aid of a thermogravimetric analyzer coupled with a mass spectrometer. The SO₂-captured sample was prepared in a fixed-bed reactor with a simulated flue gas containing 1500 ppm of SO₂, 5% O₂, and 5% H₂O. The kinetic equation was obtained by fitting the H₂SO₄ conversion (伪) at different heating rates with nonisothermal kinetic methods called Flynn鈥揥all鈥揙zawa and Coats鈥揜edfern. The results indicated that the regeneration kinetic behavior varies with 伪. At 伪 = 0.1鈥?.4, regeneration follows first-order reaction model f(伪) = 1 鈥?伪 with an activation energy of about 85.7 kJ/mol. At 伪 = 0.5鈥?.8, regeneration follows three-dimensional diffusion model f(伪) = 1.5(1 鈥?伪)^2/3[1 鈥?(1 鈥?伪)^1/3]^鈭?, with the activation energy increasing from 88.9 kJ/mol at 伪 = 0.5 to 112.1 kJ/mol at 伪 = 0.8.