Carbon dioxide(CO2) capture using magnesium oxide(MgO)-based adsorbents at intermediate temperatures has been regarded as a very prospective technology for their relatively high adsorption capacity,low cost, and wide ...Carbon dioxide(CO2) capture using magnesium oxide(MgO)-based adsorbents at intermediate temperatures has been regarded as a very prospective technology for their relatively high adsorption capacity,low cost, and wide availability. During the past few years, great effort has been devoted to the fabrication of molten salts-modified MgO-based adsorbents. The extraordinary progress achieved by coating with molten salts greatly promotes the CO_2 capture capacity of MgO-based adsorbents. Therefore, we feel it necessary to deliver a timely review on this type of CO_2 capturing materials, which will benefit the researchers working in both academic and industrial areas. In this work, we classified the molten saltsmodified MgO adsorbents into four categories:(1) homogenous molten salt-modified MgO adsorbents,(2) molten salt-modified double salts-based MgO adsorbents,(3) mixed molten salts-modified MgO adsorbents, and(4) molten salts-modified MgO-based mixed oxides adsorbents. This contribution critically reviews the recent developments in the synthetic method, adsorption capacity, reaction kinetics, promotion mechanism, operational conditions and regenerability of the molten salts-modified MgO CO_2 adsorbents. The challenges and prospects in this promising field of molten salts-modified MgO CO_2 adsorbents in real applications are also briefly mentioned.展开更多
Herein we report a systematical investigation on the promoting effect of the carbon chain length of the intercalated carboxylic anions on the CO_2 capture performance of Mg-Al layer double hydroxides(LDHs).A series of...Herein we report a systematical investigation on the promoting effect of the carbon chain length of the intercalated carboxylic anions on the CO_2 capture performance of Mg-Al layer double hydroxides(LDHs).A series of organo-LDHs were successfully synthesized via co-precipitation and calcination-rehydration methods. All as-prepared samples were characterized by many techniques including XRD, ATR-FTIR, BET,and TGA. The XRD and ATR-FTIR studies indicated that organic anions were successfully intercalated into LDHs. The influence of some important parameters such as calcination temperature, adsorption temperature, and coating with(Li-Na-K)NO_3 molten salt was investigated. The results exhibited that when the number of carbon is greater than 10, the CO_2 capture capacity steadily increased with the increase in carbon number. After coating with 55 mol%(Li-Na-K)NO_3 molten salt, the CO_2 uptake of LDH-C16 sample with high Mg/Al ratios can be increased up to 3.25 mmol/g. The CO_2 adsorption/desorption cycling stability was also studied using temperature swing adsorption, which showed a stable CO_2 capture performance even after 22 cycles. Considering its high CO_2 capture capacity and good cycling stability, this novel CO_2 adsorbent is very promising in the sorption-enhanced water gas shift(SEWGS) processes.展开更多
基金the Fundamental Research Funds for the Central Universities (2016ZCQ03)Beijing Excellent Young Scholar (2015000026833ZK11)+1 种基金the National Natural Science Foundation of China (51622801, 51572029, and 51308045)the Xu Guangqi grant
文摘Carbon dioxide(CO2) capture using magnesium oxide(MgO)-based adsorbents at intermediate temperatures has been regarded as a very prospective technology for their relatively high adsorption capacity,low cost, and wide availability. During the past few years, great effort has been devoted to the fabrication of molten salts-modified MgO-based adsorbents. The extraordinary progress achieved by coating with molten salts greatly promotes the CO_2 capture capacity of MgO-based adsorbents. Therefore, we feel it necessary to deliver a timely review on this type of CO_2 capturing materials, which will benefit the researchers working in both academic and industrial areas. In this work, we classified the molten saltsmodified MgO adsorbents into four categories:(1) homogenous molten salt-modified MgO adsorbents,(2) molten salt-modified double salts-based MgO adsorbents,(3) mixed molten salts-modified MgO adsorbents, and(4) molten salts-modified MgO-based mixed oxides adsorbents. This contribution critically reviews the recent developments in the synthetic method, adsorption capacity, reaction kinetics, promotion mechanism, operational conditions and regenerability of the molten salts-modified MgO CO_2 adsorbents. The challenges and prospects in this promising field of molten salts-modified MgO CO_2 adsorbents in real applications are also briefly mentioned.
基金supported by the Fundamental Research Funds for the Central Universities (2016ZCQ03)Beijing Excellent Young Scholar (2015000026833ZK11)+1 种基金the National Natural Science Foundation of China (51622801,51572029,and 51308045)the Xu Guangqi Grant
文摘Herein we report a systematical investigation on the promoting effect of the carbon chain length of the intercalated carboxylic anions on the CO_2 capture performance of Mg-Al layer double hydroxides(LDHs).A series of organo-LDHs were successfully synthesized via co-precipitation and calcination-rehydration methods. All as-prepared samples were characterized by many techniques including XRD, ATR-FTIR, BET,and TGA. The XRD and ATR-FTIR studies indicated that organic anions were successfully intercalated into LDHs. The influence of some important parameters such as calcination temperature, adsorption temperature, and coating with(Li-Na-K)NO_3 molten salt was investigated. The results exhibited that when the number of carbon is greater than 10, the CO_2 capture capacity steadily increased with the increase in carbon number. After coating with 55 mol%(Li-Na-K)NO_3 molten salt, the CO_2 uptake of LDH-C16 sample with high Mg/Al ratios can be increased up to 3.25 mmol/g. The CO_2 adsorption/desorption cycling stability was also studied using temperature swing adsorption, which showed a stable CO_2 capture performance even after 22 cycles. Considering its high CO_2 capture capacity and good cycling stability, this novel CO_2 adsorbent is very promising in the sorption-enhanced water gas shift(SEWGS) processes.
