TY - JOUR
T1 - Thermal decomposition behavior of MnO2/Mg-Al layered double hydroxide after removal and recovery of acid gas
AU - Kameda, Tomohito
AU - Kurutach, Tanya
AU - Takahashi, Yuriko
AU - Kumagai, Shogo
AU - Saito, Yuko
AU - Fujita, Satoshi
AU - Itou, Ichirou
AU - Han, Tianye
AU - Yoshioka, Toshiaki
N1 - Publisher Copyright:
© 2022 The Author(s)
PY - 2022/1
Y1 - 2022/1
N2 - Acidic gases such as HCl, SO2, and NOx are compounds that are generated through the incineration of waste products. Hence, an efficient method of removing such gases is highly desired. In this study, we present a novel method for treatment of acidic gases by using an MnO2/Mg-Al layered double hydroxide (MnO2/Mg-Al LDH), which provides several advantages in removing NO when compared to other removal methods, in addition to enabling the removal of HCl and SO2. We tested the recovery of acidic gases using the dry process, which separates the adsorbed gases from the LDH and recovers them as gases again, allowing them to be reused, and the adsorbent to be regenerated. To achieve this, we analyzed the pyrolysis behavior of MnO2/Mg-Al LDH at different temperatures and with various acidic gases adsorbed, using thermogravimetry (TG) and evolved gas analysis-mass spectrometry (EGA-MS), and further studied the recovery of adsorbed acidic gases. For HCl, NO, and SO2, outlet concentrations of 4000, 1000, and 950 ppm, respectively, were achieved, with recovery rates above 99% for all three. Additionally, we identified that for removal of both HCl and NO, MnO2/Mg-Al LDH desorbed the acid gas and generated Mg-Al layered double oxide (Mg-Al LDO) as the LDH structure collapsed. Furthermore, for SO2 removal, MgAl2O4 and MgO were generated. Overall, we confirmed that acidic gases such as HCl, NO, and SO2, can be recovered with high efficiency and at a high concentration by using MnO2/Mg-Al LDH. This method of removal can have many potential applications.
AB - Acidic gases such as HCl, SO2, and NOx are compounds that are generated through the incineration of waste products. Hence, an efficient method of removing such gases is highly desired. In this study, we present a novel method for treatment of acidic gases by using an MnO2/Mg-Al layered double hydroxide (MnO2/Mg-Al LDH), which provides several advantages in removing NO when compared to other removal methods, in addition to enabling the removal of HCl and SO2. We tested the recovery of acidic gases using the dry process, which separates the adsorbed gases from the LDH and recovers them as gases again, allowing them to be reused, and the adsorbent to be regenerated. To achieve this, we analyzed the pyrolysis behavior of MnO2/Mg-Al LDH at different temperatures and with various acidic gases adsorbed, using thermogravimetry (TG) and evolved gas analysis-mass spectrometry (EGA-MS), and further studied the recovery of adsorbed acidic gases. For HCl, NO, and SO2, outlet concentrations of 4000, 1000, and 950 ppm, respectively, were achieved, with recovery rates above 99% for all three. Additionally, we identified that for removal of both HCl and NO, MnO2/Mg-Al LDH desorbed the acid gas and generated Mg-Al layered double oxide (Mg-Al LDO) as the LDH structure collapsed. Furthermore, for SO2 removal, MgAl2O4 and MgO were generated. Overall, we confirmed that acidic gases such as HCl, NO, and SO2, can be recovered with high efficiency and at a high concentration by using MnO2/Mg-Al LDH. This method of removal can have many potential applications.
KW - Acid gas recovery
KW - Acid gas removal
KW - MnO/Mg-Al layered double hydroxide
KW - Thermal decomposition behavior
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U2 - 10.1016/j.rechem.2022.100310
DO - 10.1016/j.rechem.2022.100310
M3 - Article
AN - SCOPUS:85124709076
SN - 2211-7156
VL - 4
JO - Results in Chemistry
JF - Results in Chemistry
M1 - 100310
ER -