类水滑石Ti/Li/Al-LDHs的制备及其CO_2吸附性能

采用共沉淀法制备了一系列新型的类水滑石Ti/Li/Al-LDHs材料,通过原子吸收光谱(AAS)、X射线衍射(XRD)、扫描电镜(SEM)、热重分析(TG)和傅里叶变换红外光谱(FT-IR)等技术对其进行了表征,研究了不同金属元素比例和焙烧温度对该Ti/Li/Al-LDHs材料的结构、形貌及其CO_2吸附性能的影响。结果表明,当Ti/Li/Al比为1∶3∶4时,水滑石Ti/Li/AlLDHs的结晶度最好,形貌最规整,而Ti/Li/Al比为1∶3∶2、300℃下焙烧后得到的Ti_1Li_3Al_2-LDHs_(300)的CO_2吸附性能最好。Ti_1Li_3Al_2-LDHs_(300)上CO_2吸附量可达53.5 mg/g,10次循环吸附后,CO_2吸附量仅下降了2.4%。

Preparation of hydrotalcite-like Ti/Li/Al-LDHs and its performance in CO2 adsorption

A series of hydrotalcite-like Ti/Li/Al-LDHs materials were prepared by co-precipitation method and characterized by atomic absorption spectrophotometer (AAS), X-ray diffraction (XRD), scanning electron microscopy (SEM), thermal gravimetric analysis (TG) and Fourier transform infrared (FT-IR); the influence of metal composition and calcination temperature on the structure, morphology and CO₂ adsorption capacity of Ti/Li/Al-LDHs was investigated. The results showed that Ti₁Li₃Al₄-LDHs obtained with a Ti/Li/Al ratio of 1:3:4 displays the highest crystallinity and regular morphology, whereas Ti₁Li₃Al₂-LDHs₃₀₀ prepared with a Ti/Li/Al ratio of 1:3:2 and calcined at 300℃ exhibits the best adsorption performance towards CO₂. The CO₂ adsorption capacity over Ti₁Li₃Al₂-LDHs₃₀₀ reaches 53.5mg/g; in addition, the adsorption capacity is only decreased by 2.4% after adsorption for 10 cycles.