The effect of Kaolinite’s structure on migration and release characteristics of sodium under oxy-fuel combustion condition
The effect of Kaolinite’s structure on migration and release characteristics of sodium under oxy-fuel combustion condition
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高岭石结构对全氧燃烧条件下钠迁移和释放特性的影响
DOI：
10.1016/j.fuel.2020.118154
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发表时间：
2020-10
期刊：
影响因子：
7.4
通讯作者：
Hongjian Tang
中科院分区：
文献类型：
--
作者：
Kaijun Yu;Cai Liang;Daoyin Liu;Tianyi Cai;Jiliang Ma;Xiaoping Chen;Hongjian Tang
研究高岭石对氯化钠的吸附性能对高钠煤的应用具有重要意义，但富氧燃烧气氛中高浓度的水蒸气增加了该过程的不确定性。而且，在相应条件下，煅烧和插层剥离后高岭石对钠离子的吸附性能研究还很少。因此，本文对高岭石的钠吸附特性进行了研究。本工作通过实验和DFT计算研究，进一步评估了H2O对其钠保留能力的影响。随着添加剂比例的增加，灰分中的钠含量也增加，但比例超过9%后，增加不明显。插层剥离后的高岭土对氯化钠的吸附性能得到了明显的改善。为了证实这一结论，本文还用纯氯化钠进行了吸附实验，得到了类似的结果。大气中水蒸气浓度（0 - 45%）的变化对氯化钠在高岭石表面的吸附有很强的影响。H2O与脱羟基表面的相互作用较强，能及时补充表面因高温而缺失的吸附位。实验结果表明，在20%的压力下，动平衡可以达到。然而，H2O和氯化钠在完全吸附表面上相互竞争，这降低了钠的固定。
Studying the adsorption properties of kaolinite on sodium chloride is of great significance for application of high sodium coal, but high concentration of steam in the oxy-fuel combustion atmosphere increases the uncertainty of this process. Moreover, under the corresponding condition, the research on the adsorption properties of sodium of kaolinite after calcination and intercalation-exfoliation is still scarce. Therefore, this paper carried out a study on sodium adsorption characteristics of kaolinite. This work further evaluated H2O influence on its Na retention ability via integrating experimental and DFT computational studies. As the proportion of additive increases, the sodium content in the ash also increases, but after the ratio exceeds 9%, the increase is not obvious. The kaolinite’s adsorption performance on sodium chloride has been significantly improved after the intercalation-exfoliation. In order to confirm this conclusion, this paper also carried out adsorption experiments using pure sodium chloride, and obtained similar results. Variations in the concentration of steam (0–45%) in the atmosphere have a strong effect on the adsorption of sodium chloride on the surface of kaolinite. Moreover, both acceleration and competition effects of H2O on surface-bound Na species were substantiated by DFT calculations·H2O showed a stronger interaction with the dehydroxylated surface, can promptly replenish the missing adsorption sites on the surface due to high temperature. The experimental results show that the dynamic balance can be achieved at 20%. However, H2O and sodium chloride compete with each other on the complete adsorption surface, which reduces the fixation of sodium.
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影响因子：
5.7
作者：
Chang’an Wang;Yinhe Liu;Xi Jin;D. Che
通讯作者：
Chang’an Wang;Yinhe Liu;Xi Jin;D. Che
中国西北部新疆准噶尔煤田南部和东部侏罗系煤的高品质：地球化学和矿物学特征
影响因子：
5.6
作者：
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Lei, Guoming
影响因子：
7.4
作者：
Z. Zeng;K. Natesan;Z. Cai;D. Rink
通讯作者：
Z. Zeng;K. Natesan;Z. Cai;D. Rink
影响因子：
7.4
作者：
K. Tran;K. Iisa;M. Hagström;B. Steenari;O. Lindqvist;J. Pettersson
通讯作者：
K. Tran;K. Iisa;M. Hagström;B. Steenari;O. Lindqvist;J. Pettersson
影响因子：
3.7
作者：
MONKHORST, HJ;PACK, JD
通讯作者：
PACK, JD