Enhancement of reactivity in Li4SiO4-based sorbents from the nano-sized rice husk ash for high-temperature CO2 capture
Enhancement of reactivity in Li4SiO4-based sorbents from the nano-sized rice husk ash for high-temperature CO2 capture
复制标题
提高纳米稻壳灰中 Li4SiO4 基吸附剂的反应活性，用于高温 CO2 捕获
DOI：
10.1016/j.enconman.2014.02.054
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发表时间：
2014-05
影响因子：
10.4
通讯作者：
Chao, Yang
中科院分区：
文献类型：
--
作者：
Guo, Xin;Li, Yimin;Han, Dongtai;Chao, Yang
以低成本、可再生的纳米级柠檬酸预处理稻壳灰（CRHA）为硅源，通过低温固相反应制备了高效的硅酸锂基高温CO2捕集剂（CRHA-Li 4SiO 4）。为了比较两种典型的原料（纳米结构的气溶胶和结晶石英粉）用于合成Li 4SiO 4吸附剂（气溶胶-Li 4SiO 4和石英-Li 4SiO 4）。通过分析技术研究了硅源、热处理原料和接收态Li 4SiO 4吸附剂的相组成行为、比表面积和形貌。采用热重分析仪（CO2气氛）和固定床反应器分别测试了其CO2吸附量和吸附-脱附性能。与原始样品相比，热处理后原料的形貌对其相组成、微观结构、比表面积和CO2吸附性能有较大影响。虽然煅烧后的石英样品保持了微米颗粒的结构，但其反应性不足以与Li 2CO 3完全反应。由于纳米颗粒的反应性更强，气溶胶-Li 4SiO 4呈现出纯Li 4SiO 4的形貌，而其颗粒较大，形貌致密，这是由于煅烧过程中SiO2纳米颗粒的明显熔融所致。相反，CRHA-Li 4SiO 4实现了亚微米颗粒的多孔团聚体，这是由于其煅烧的CRHA的高抗烧结特性。热重分析和固定床实验结果表明，CRHA-Li 4SiO 4的结构有利于提高CO2的吸附容量（6.92 mmol/g Li 4SiO 4，吸附效率83.1%），并具有较快的动力学行为和较好的再生性能（从第1次循环到第15次循环，吸附容量仅下降2.1 wt%）。
Using the cost-effective, renewable and nano-sized of citric acid pretreatment rice husk ash (CRHA) as silicon source, high efficient Li4SiO4(lithium orthosilicate)-based sorbents (CRHA-Li4SiO4) for high-temperature CO2capture were prepared through the solid-state reaction at lower temperature (700 °C). Two typical raw materials (nano-structured Aerosil and crystalline Quartz powders) were used to synthesize Li4SiO4sorbents (Aerosil-Li4SiO4and Quartz-Li4SiO4) for comparison purposes. The phase composition behavior, surface area, and morphology of the silicon sources, heat treated raw materials and as-received Li4SiO4sorbents were studied by analytical techniques. The CO2adsorption capacity and adsorption–desorption performance were tested by the thermo-gravimetric analyses (CO2atmosphere) and a fixed bed reactor, respectively. Compared with the case of its original samples, the morphology of heat treated raw materials had a greater effect on the phase composition, microstructure, special surface area and CO2adsorption properties of their resulting sorbents. Although the calcined Quartz sample maintained the structure of micron particles, its reactivity was not enough to react completely with Li2CO3. Due to the greater reactivity of nanoparticles, Aerosil-Li4SiO4presented pure of Li4SiO4whereas it obtained large particles with dense morphology, which was coming from the pronounced fusing of silica nanoparticles during the calcined process. Conversely, CRHA-Li4SiO4achieved porous agglomerates of submicron particles resulting from a high anti-sintering character of its calcined CRHA. This more favorable structure of CRHA-Li4SiO4could lead to the higher CO2adsorption capacity of 30.5 wt% (6.92 mmol/g Li4SiO4, corresponding to 83.1% efficiency), faster kinetic behavior and better regenerability (its adsorption capacity only decreased 2.1 wt% from the first cycle to the 15th cycle), which was illustrated by the thermogravimetric analyses and fix bed results.
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影响因子：
15.1
作者：
Huichao Chen;Changsui Zhao
通讯作者：
Huichao Chen;Changsui Zhao
用于高温 CO2 捕集的新型硅藻土 Li4SiO4 基吸附剂
影响因子：
5.2
作者：
Shan SY;Jia QM;Jiang LH;Wang YM;Peng JH
通讯作者：
Peng JH
影响因子：
10.4
作者：
Y. Ge;S. Tassou
通讯作者：
Y. Ge;S. Tassou
影响因子：
3.1
作者：
H. Pfeiffer;P. Bosch;S. Bulbulian
通讯作者：
H. Pfeiffer;P. Bosch;S. Bulbulian
影响因子：
4.2
作者：
Venegas, Miriam J.;Fregoso-Israel, Esteban;Pfeiffer, Heriberto
通讯作者：
Pfeiffer, Heriberto