Highly pure amorphous silica nano-disks from rice straw
Highly pure amorphous silica nano-disks from rice straw
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DOI：
10.1016/j.powtec.2012.04.002
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发表时间：
2012-07-01
影响因子：
5.2
通讯作者：
Hsieh, You-Lo
中科院分区：
文献类型：
--
作者：
Lu, Ping;Hsieh, You-Lo
白色灰，主要成分为SiO2，并含有微量的Al 2 O3、CaO、MgO、K2 O、P2 O 5等，通过以10 ℃/min的速度加热稻草并在250、325和575 ℃下保持以促进有机物的分解和气化同时避免自燃，成功地制备了高纯度的无定形二氧化硅。通过碱溶解和酸沉淀过程，以90.8%的产率（或11.47%来自稻草）从所得稻草灰得到高纯无定形二氧化硅。通过EDS和FTIR证实了SiO2的化学组成，并通过XRD证实了SiO2的无定形性质。硅胶的冷冻干燥产生具有5.8 nm平均孔径（2至22 nm孔径分布）和非常高的比表面积（509.5 m（2）/g BET和637.0 m（2）/g BJH）和孔体积（0.925 cm（3）/g）的中孔二氧化硅粉末。这些二氧化硅粉末可分散在水中，并显示出由平均直径为172 nm，厚度为3.09 nm的纳米盘，分别通过TEM和AFM测量。(C)2012爱思唯尔有限公司版权所有。
White ash, containing majority of SiO2 with trace amounts of Al2O3, CaO, MgO, K2O, P2O5, etc., was successfully produced by heating rice straw at 10 degrees C/min and holding at 250, 325 and 575 degrees C to facilitate decomposition and gasification of the organics while avoiding auto-ignition, Highly pure amorphous silica was derived from the resultant rice straw ash by a base dissolution and acid precipitation process at a 90.8% yield (or 11.47% from rice straw). The SiO2 chemical composition was confirmed by EDS and FTIR and the amorphous nature by XRD. Freeze-drying of silica gel produced mesoporous silica powders with a 5.8 nm average pore size (2 to 22 nm pore size distribution) and very high specific surface (509.5 m(2)/g BET and 637.0 m(2)/g BJH) and pore volume (0.925 cm(3)/g). These silica powders were dispersible in water and shown to consist of nano-disks with an average 172 nm diameter and 3.09 nm thickness as measured by TEM and AFM, respectively. (C) 2012 Elsevier B.V. All rights reserved.