Millions of people in poor areas are still under the threat of fluoride contamination.How to effectively separate fluorine in water is an important step to reduce the ecological risk.In this paper,we performed a syste...Millions of people in poor areas are still under the threat of fluoride contamination.How to effectively separate fluorine in water is an important step to reduce the ecological risk.In this paper,we performed a systematic DFT calculation focused on the defluorination behavior between the LiAl-and MgAl-LDHs.The results indicated that the LiAl-LDHs exhibited high chemical activity before the defluorination,because of the better electronic structure.After the defluorination,the LiAl-LDHs with adsorbed-F–were also more stable than the MgAl-LDHs.In addition,the existence of coordination covalent bond for the adsorbed-F–attached to the LiAl-LDHs was confirmed.This is an important reason for the high defluorination efficiency by the LiAl-LDHs.In addition,a series of weak interaction,including hydrogen bond and van der Waals interaction were also observed.Finally,a LiAl-LDHs with excellent fluoride removal properties were synthesized well by simple hydrothermal method.The results showed that our synthesized LiAl-LDHs with the capacity of 156.09 mg/g,could be effectively defluorinated in water.Notably,it surpasses most materials and has potential applications.展开更多
Because of its high mobility and difficult capture,gaseous arsenic pollution control has become the focus of arsenic pollution control.It mainly exists in the form of highly toxic As_(2)O_(3)in the flue gas.Therefore,...Because of its high mobility and difficult capture,gaseous arsenic pollution control has become the focus of arsenic pollution control.It mainly exists in the form of highly toxic As_(2)O_(3)in the flue gas.Therefore,removing gaseous As_(2)O_(3)from flue gas is of great practical significance for arsenic pollution control.Stabilizing gaseous As_(2)O_(3)on the surface of adsorbents by physical or chemical adsorption is an effective way to reduce the content of arsenic in the flue gas and alleviate arsenic pollution.Over the past few decades,various adsorbents have been developed to capture gaseous As_(2)O_(3)in the flue gas,and their adsorption mechanisms have been studied in detail.Thus,it is necessary to review the strategies of arsenic removal from flue gas by adsorption,which can inspire further research.Based on summarizing the morphological distribution of gaseous As_(2)O_(3)in the flue gas,this review further summarizes the removal of gaseous As_(2)O_(3)by several adsorbents and the effect of temperature and the main components of the flue gas on arsenic adsorption.In addition,the mechanism of arsenic removal based on adsorption in the flue gas is discussed in depth through theoretical calculations,which is the particular focus of this review.Finally,prospects based on the present research state of arsenic removal by adsorption are proposed to provide ideas for developing effective and stable adsorbents for arsenic removal from flue gas.展开更多
基金supported by the National Science Fund for Distinguished Young Scholars (No.52022111)the Natural Science Foundation of China (No.51974379)the Scientific and Technological Innovation Program of Hunan Province,Huxiang Youth Talent Project (No.2020RC_(3)012)。
文摘Millions of people in poor areas are still under the threat of fluoride contamination.How to effectively separate fluorine in water is an important step to reduce the ecological risk.In this paper,we performed a systematic DFT calculation focused on the defluorination behavior between the LiAl-and MgAl-LDHs.The results indicated that the LiAl-LDHs exhibited high chemical activity before the defluorination,because of the better electronic structure.After the defluorination,the LiAl-LDHs with adsorbed-F–were also more stable than the MgAl-LDHs.In addition,the existence of coordination covalent bond for the adsorbed-F–attached to the LiAl-LDHs was confirmed.This is an important reason for the high defluorination efficiency by the LiAl-LDHs.In addition,a series of weak interaction,including hydrogen bond and van der Waals interaction were also observed.Finally,a LiAl-LDHs with excellent fluoride removal properties were synthesized well by simple hydrothermal method.The results showed that our synthesized LiAl-LDHs with the capacity of 156.09 mg/g,could be effectively defluorinated in water.Notably,it surpasses most materials and has potential applications.
基金supported by the National Science Fund for Excellent Young Scholars of China (No.52022111)the Foundation for Innovative Research Groups of the National Natural Science Foundation of China (No.52121004)+1 种基金the Hunan High Tech Industry Science and Technology Innovation Leading Plan Project (No.2020SK2006)the Huxiang Youth Talent Support Program (No.2020RC3012)。
文摘Because of its high mobility and difficult capture,gaseous arsenic pollution control has become the focus of arsenic pollution control.It mainly exists in the form of highly toxic As_(2)O_(3)in the flue gas.Therefore,removing gaseous As_(2)O_(3)from flue gas is of great practical significance for arsenic pollution control.Stabilizing gaseous As_(2)O_(3)on the surface of adsorbents by physical or chemical adsorption is an effective way to reduce the content of arsenic in the flue gas and alleviate arsenic pollution.Over the past few decades,various adsorbents have been developed to capture gaseous As_(2)O_(3)in the flue gas,and their adsorption mechanisms have been studied in detail.Thus,it is necessary to review the strategies of arsenic removal from flue gas by adsorption,which can inspire further research.Based on summarizing the morphological distribution of gaseous As_(2)O_(3)in the flue gas,this review further summarizes the removal of gaseous As_(2)O_(3)by several adsorbents and the effect of temperature and the main components of the flue gas on arsenic adsorption.In addition,the mechanism of arsenic removal based on adsorption in the flue gas is discussed in depth through theoretical calculations,which is the particular focus of this review.Finally,prospects based on the present research state of arsenic removal by adsorption are proposed to provide ideas for developing effective and stable adsorbents for arsenic removal from flue gas.
