Migration and speciation transformation of K and Cl caused by interaction of KCl with organics during devolatilization of KCl-loaded model biomass compounds
Migration and speciation transformation of K and Cl caused by interaction of KCl with organics during devolatilization of KCl-loaded model biomass compounds
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负载 KCl 的模型生物质化合物脱挥发分过程中 KCl 与有机物相互作用引起的 K 和 Cl 的迁移和形态转化
DOI：
10.1016/j.fuel.2020.118205
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发表时间：
2020-10
期刊：
影响因子：
7.4
通讯作者：
Chuangzhi Wu
中科院分区：
文献类型：
--
作者：
Yanqin Huang;Huacai Liu;Hongyou Yuan;Xianchao Lv;Bin Xu;Weizhen Li;Jenjira Uttaruean;Xiuli Yin;Chuangzhi Wu
为了更好地理解由KCl与有机物的相互作用引起的K和Cl的迁移，使用固定床装置在300-800 °C内热解负载KCl的模型化合物（纤维素、木聚糖、木质素和果胶）。采用连续化学形态分析结合ICP-OES和IC对煤焦中K和Cl的不同化学形态进行了定量分析。通过XPS和SEM-EDS进一步研究了Cl和K的形态和存在方式。4个样品中K和Cl的迁移存在较大差异，这种差异与有机官能团的类型密切相关。在低于500 °C的温度下，从四个样品中释放出低比例的K，而大量的水溶性K通过不同的离子交换反应机制转化为有机结合形式，从而促进Cl释放。木质素和果胶焦中有机钾含量分别为46.93-53.31%和32.47-41.75%，明显高于木聚糖和纤维素焦。同时，掺杂果胶中Cl的释放量（71.98-81.83%）依次为木质素（35.12-52.34%）、纤维素（18.56-35.68%）和木聚糖（10.67-18.65%）。释放出的部分Cl被活性炭吸附，形成有机氯，C-Cl生成量顺序为木质素>木聚糖>纤维素>果胶。随着热解的进行，纤维素表现出最高的钾释放由于有机钾的分解，而相当一部分具有较高的热稳定性的焦炭钾仍然保留在其他样品。提出了KCl与有机物反应导致K、Cl迁移的机理。
To better understand migration of K and Cl caused by interaction of KCl with organics, KCl-loaded model compounds (cellulose, xylan, lignin and pectin) were pyrolyzed within 300–800 °C using a fixed-bed apparatus. The amounts of different chemical occurrences of K and Cl in chars were quantitatively determined by sequential chemical fraction analysis combined with ICP-OES and IC. Morphologies and occurrence modes of Cl and K were further examined via XPS and SEM-EDS. Big differences in K and Cl migration were observed among four samples, and the distinction was closely related to types of organic functional groups. At temperature of below 500 °C, a low proportion of K was released from four samples, while amounts of water-soluble K was transformed into organically-bounded form via different ion-exchange reaction mechanisms, thereby promoting Cl release. About 46.93–53.31% and 32.47–41.75% of organic-K, presumably formed by reaction of KCl and methoxyls, were detected in lignin and pectin chars, apparently higher than that in xylan and cellulose chars. At the same time, amounts (71.98–81.83%) of Cl was released from doped pectin, followed sequentially by lignin (35.12–52.34%), cellulose (18.56–35.68%), and xylan (10.67–18.65%). Part of released Cl was recaptured by active carbon sites, thereby forming organochlorine, and C-Cl generation followed a sequence of lignin > xylan > cellulose > pectin. As pyrolysis proceeded, cellulose exhibited highest K release due to decomposition of organic-K, while a considerable of char-K with high thermal stability still retained in other samples. Mechanism on migration of K and Cl caused by reaction of KCl with organics was proposed.
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DOI：
10.1016/j.proci.2014.07.020
发表时间：
2015
期刊：
--
影响因子：
--
作者：
M. U. Rahim;Xiangpeng Gao;Hongwei Wu
通讯作者：
M. U. Rahim;Xiangpeng Gao;Hongwei Wu
影响因子：
5.3
作者：
S. Saleh;Julie Pauline Flensborg;Tooran Khazraie Shoulaifar;Z. Sárossy;B. B. Hansen-B.;H. Egsgaard;N. Demartini;P. Jensen;P. Glarborg;K. Dam‐Johansen
通讯作者：
S. Saleh;Julie Pauline Flensborg;Tooran Khazraie Shoulaifar;Z. Sárossy;B. B. Hansen-B.;H. Egsgaard;N. Demartini;P. Jensen;P. Glarborg;K. Dam‐Johansen
影响因子：
7.4
作者：
Yang Wang;Hao Wu;Z. Sárossy;C. Dong;P. Glarborg
通讯作者：
Yang Wang;Hao Wu;Z. Sárossy;C. Dong;P. Glarborg
影响因子：
5.3
作者：
J. N. Knudsen;P. Jensen;A. W. Lin;K. Dam‐Johansen
通讯作者：
J. N. Knudsen;P. Jensen;A. W. Lin;K. Dam‐Johansen
影响因子：
7.2
作者：
Hou, Hongying;Wang, Suli;Sun, Gongquan
通讯作者：
Sun, Gongquan