The release of K during thermal utilization of biomass can cause fouling, slagging, and other technical problems, while released K might be recaptured by biomass char. In this work, cellulose char was used as a raw material to avoid the effects of inorganic elements in biomass char. The capture of gaseous KCl by cellulose char was examined at 900–1000 °C in a double-layer fixed-bed reactor. The temporal capture pattern was obtained on the basis of an analysis of char samples after capture for different durations, and the stability and association of captured K were analyzed. Cellulose char showed a remarkable ability to capture gaseous KCl. The increase in the K content captured by the char was rapid at first, decreased with time, and eventually reached 0. With the temperature increasing from 900 to 1000 °C, the saturated content of captured K increased from 4.1 to 5.5% and reached saturation more rapidly. The capture abilities of char with different pyrolysis degrees were identical. The K/Cl ratio and scanning electron microscopy and energy-dispersive spectroscopy analysis of the captured char indicated that KCl capture by char occurred primarily through the reaction of the organic structure with KCl to generate char–K and through the adsorption of KCl. Under an Ar atmosphere, K captured in char was partially released again to the gas phase but an amount remained stable in the char in the form of char–K. This content was approximately 1.7% and was not related to the pyrolysis temperature. Captured K existed mainly as water-soluble and insoluble K. In the thermal stability experiment, both water-soluble and insoluble K can be partly released to gas but more insoluble K was released than water-soluble K, which meant that the ratio of water-soluble K in char obviously increased.

中文翻译：

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纤维素焦炭捕获气态氯化钾的研究

生物质热利用过程中释放的K会导致结垢，结渣和其他技术问题，而释放的K可能会被生物质炭捕获。在这项工作中，以纤维素炭为原料，避免了生物质炭中无机元素的影响。在双层固定床反应器中于900–1000°C下检查了纤维素焦炭对气态KCl的捕集。根据对不同持续时间捕获后的焦炭样​​品的分析，获得了时间捕获模式，并对捕获的钾的稳定性和缔合性进行了分析。纤维素焦炭表现出了出色的捕获气态氯化钾的能力。炭捕获的K含量起初迅速增加，随时间降低，最终达到0。随着温度从900升高到1000°C，捕获的钾的饱和含量从4.1％增加到5.5％，并更快地达到饱和。不同热解度的焦炭的捕集能力是相同的。捕获的焦炭的K / Cl比值，扫描电子显微镜和能谱分析表明，焦炭对KCl的捕获主要是通过有机结构与KCl的反应生成char-K以及通过KCl的吸附而发生的。在Ar气氛下，焦炭中捕获的K再次部分释放到气相中，但以焦炭-K的形式在焦炭中保持稳定。该含量为约1.7％，并且与热解温度无关。捕获的钾主要以水溶性和不溶性钾的形式存在。在热稳定性实验中，