一种高岭土基多孔硅材料的制备及其对Ca^(2+)和Mg^(2+)的吸附（英文）

Amorphous Silica Material Prepared from Kaolin and Its Adsorption Properties to Ca^(2+) and Mg^(2+)

成功合成了一种高岭土基新型多孔硅材料(ASM)并以FTIR,XRD,FE-SEM和N2吸附-脱附进行了系统的表征。ASM的制备过程涉及两步:SiO_3^(2-)提取和ASM的制备。SiO_3^(2-)提取的最优条件为煅烧温度为960℃,Na OH浓度为20%,反应温度为90℃,反应时间为90 min,在此条件下SiO_3^(2-)提取率为60.45%(w/w)。以此提取液为原材料,调整提取液中SiO_3^(2-)的浓度为12 g·L-1,反应温度为90℃,反应时间为60 min,然后再搅拌2 h可制得ASM。以此ASM对Ca^(2+)和Mg^(2+)进行吸附研究,脱除率分别可达94.99%和62.32%。

A novel amorphous silica material （ASM） was successfully prepared from kaolin and characterized by several techniques, including Fourier transform infrared spectroscopy （FTIR）, X-ray diffraction （XRD）, field emission scanning electron microscopy （FE-SEM）, and N2 adsorption-desorption. The preparation procedure of ASM involved two aspects： SiO3 2- leaching from kaolin and preparation of ASM. The optimum SiO3 2- leaching condition was confirmed at calcination temperature of 960 ℃, NaOH concentration of 20%, reaction temperature of 90 ℃ and reaction time of 90 rain. Under this condition, SiO3 2- leaching yield arrived at 60.45%（w/w）. The ASM was then easily prepared from SiO3 2- leaching at the silica concentration of 12 g.L-1, reaction temperature of 90 ℃, reaction time of 60 rain and aging time of 2 h. The removal behavior of Ca2＋ and Mg2＋ revealed that the removal rate of Ca2＋ and Mg2＋ on the ASM could arrived at 94.99% and 62.32%, respectively.