title: Alkali-Doped Lithium Orthosilicate Sorbents for Carbon Dioxide Capture.
abstract: New alkali-doped (Na2 CO3 and K2 CO3 ) Li4 SiO4 sorbents with excellent performance at low CO2 concentrations were synthesized. We speculate that alkali doping breaks the orderly arrangement of the Li4 SiO4 crystals, hence increasing its specific surface area and the number of pores. It was shown that 10 wt % Na2 CO3 and 5 wt % K2 CO3 are the optimal additive ratios for doped sorbents to attain the highest conversions. Moreover, under 15 vol % CO2 , the doped sorbents present clearly faster absorption rates and exhibit stable cyclic durability with impressive conversions of about 90 %, at least 20 % higher than that of non-doped Li4 SiO4 . The attained conversions are also 10 % higher than the reported highest conversion of 80 % on doped Li4 SiO4 . The performance of Li4 SiO4 is believed to be enhanced by the eutectic melt, and it is the first time that the existence of eutectic Li/Na or Li/K carbonate on doped sorbents when absorbing CO2 at high temperature is confirmed; this was done using systematical analysis combining differential scanning calorimetry with in situ powder X-ray diffraction.
authors.affiliation: State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, 430074, Wuhan, PR China.
authors.forename: Xinwei
authors.initials: X
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, 430074, Wuhan, PR China. wenqiang.liu@hust.edu.cn.
authors.forename: Wenqiang
authors.initials: W
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, 430074, Wuhan, PR China.
authors.forename: Jian
authors.initials: J
authors.lastname: Sun
authors.affiliation: State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, 430074, Wuhan, PR China.
authors.forename: Yingchao
authors.initials: Y
authors.lastname: Hu
authors.affiliation: State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, 430074, Wuhan, PR China.
authors.forename: Wenyu
authors.initials: W
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, 430074, Wuhan, PR China.
authors.forename: Hongqiang
authors.initials: H
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, 430074, Wuhan, PR China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, 430074, Wuhan, PR China.
authors.forename: Xian
authors.initials: X
authors.lastname: Li
authors.affiliation: State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, 430074, Wuhan, PR China. mhxu@hust.edu.cn.
authors.forename: Minghou
authors.initials: M
authors.lastname: Xu
mesh_terms: D000085:Acetates / Q000737:chemistry; D002245:Carbon Dioxide / Q000737:chemistry*; D002254:Carbonates / Q000737:chemistry; D007700:Kinetics; D008094:Lithium / Q000737:chemistry*; D011188:Potassium / Q000737:chemistry; D017640:Silicates / Q000737:chemistry*
chemical_list: D000085:Acetates; D002254:Carbonates; D017640:Silicates; D002245:Carbon Dioxide; C005686:sodium carbonate; D008094:Lithium; C037593:potassium carbonate; C488804:lithium acetate; D011188:Potassium
keywords: absorption; carbon storage; carbonates; lithium silicate; sorbents