Pyrogenic carbon (PyC) nanoparticles are widespread in the environment, which is important to global carbon cycle. PyC can exist for millions of years and undergo various environmental aging processes. To better understand the roles of Fe oxyhydroxides and water content on the pristine and aged PyC transport, adsorption and column experiments were conducted under three saturations (100%, 70%, and 40%) and three pH (5, 7, and 9) in both clean and Fe oxyhydroxide-coated sand. At high water saturations (100% and 70%), the mobility of both the pristine and aged PyC was enhanced at high pH due to strong electrostatic repulsion, and the aged PyC showed higher mobility than the pristine PyC because of its more negative charge and hydrophilic surface. The coating of Fe oxyhydroxides on sand decreased the mobility of both the pristine and aged PyC due to weak electrostatic repulsion, large specific surface area, and high roughness. At low saturation (40%), solution pH showed little effect on both the pristine and aged PyC mobility, and water saturation became the main factor affecting PyC mobility. Almost no pristine or aged PyC transported out from the Fe oxyhydroxide-coated sand column because Fe oxide increased the roughness of the sand surface, which led to a sharp increase in the air-water-solid interface and retention sites. This study demonstrates that water content, environmental aging, and Fe oxyhydroxides are significant in the fate and transport of PyC nanoparticles in environments, which provides a good fundamental understanding for the assessment of pyrogenic carbon application in environmental protection and carbon sequestration.

热解碳（PyC）纳米粒子广泛存在于环境中，这对全球碳循环很重要。PyC 可以存在数百万年，并经历各种环境老化过程。为了更好地了解氢氧化铁和水含量对原始和老化 PyC 传输的作用，在三种饱和度（100%、70% 和 40%）和三种 pH 值（5、7 和 9）下进行了吸附和柱实验在干净的和氢氧化铁涂层的沙子中。在高水饱和度（100% 和 70%）下，由于强静电排斥，原始 PyC 和老化 PyC 在高 pH 值下的迁移率均得到增强，并且老化 PyC 显示出比原始 PyC 更高的迁移率，因为它具有更多的负电荷和亲水表面。由于静电斥力弱、比表面积大和粗糙度高，沙子上的羟基氧化铁涂层降低了原始和老化 PyC 的流动性。在低饱和度 (40%) 下，溶液 pH 值对原始和老化的热解碳迁移率几乎没有影响，水饱和度成为影响热解碳迁移率的主要因素。几乎没有原始或老化的 PyC 从 Fe oxyhydroxide 涂层砂柱中运出，因为 Fe 氧化物增加了砂表面的粗糙度，导致空气-水-固体界面和保留位点急剧增加。这项研究表明，水含量、环境老化和氢氧化铁对 PyC 纳米粒子在环境中的命运和运输具有重要意义，