掺杂Li4SiO4材料的CO2吸附研究

Recycling and utilizing CO2 is very important significance to realizing energy saving and emission reduction. Lithium silicate (Li4SiO4) absorbents for CO2 were prepared by high-temperature solid-state reaction. Thermodynamic equilibrium of Li4SiO4 absorp-tion CO2was discussed using the HSC5.0 code. The capability of Li4SiO4 for absorption CO2 was investigated using the thermobalance instrument. The crystal structure and surface morphologies of the Li4SiO4were also analyzed by X-ray diffraction, SEM. The results showed: the absorption reaction is fast in the temperature range 600～720 ℃, the maximum absorption rate (w) was 29.16% ; and the desorption reaction began in 750 ℃, then Li4SiO4 is regenerated. The concentrations of CO2 obviously affect on the absorption speed and the maximum absorption rate; but the flow rate of CO2 little influences the absorption capability.     

K和Ca掺杂对硅酸锂高温吸收CO2性能的影响

以SiO2和Li2CO3,为反应原料,采用高温固相法,在掺杂不同比例的K或Ca元素的条件下合成了一系列可以直接吸收CO2的硅酸锂(Li4SiO4)材料.实验结果表明,掺杂K或Ca元素都可以提高(Li4SiO4)材料对CO2的吸附率,但K和Ca的最佳掺杂量不同.不同元素掺杂对Li4SiO4吸附稳定性的影响也有不同.采用x射线衍射(XRD)初步探讨了不同元素掺杂对Li4SiO4的吸附性能影响原因.