Cr is a necessary trace element for humans and animals, but high Cr concentrations of industrial waste are dangerous for human health and environment. In order to explore the adsorption property of Cr(VI) from aqueous solution by corncob, and provide a theoretical basis for removing Cr(VI) in water, in this study, three experiments were set up: adsorption test under different pH conditions, the isothermal adsorption test, and the thermodynamics test, meanwhile, the SEM and EDS before and after Cr(VI) adsorption on corncob were analyzed, which explored the adsorption mechanism of Cr(VI) adsorption on corncob. The results showed that lower pH has a promoting effect on the adsorption and the removal effect could be optimal under pH of 1.0. The maximum removal rate and the adsorption capacity were 94.35% and 23.944 0 mg·g-1. The adsorption isotherms were in good agreement with the Langmuir, Freundlich and Dubinin-Radushkevich models, while the Freundlich model fits best. The value of 1/n was 0.887 5, indicating moderate adsorption intensity. The value E=3.152 8 kJ·mol-1 of D-R model indicated physic-sorption process. Thermodynamic parameter ΔH cor -0.272 8 kJ·mol-1, and ΔS was 0.014 3 kJ·mol-1·K-1, indicating a spontaneously exothermic process of comcob. Furthermore, the increasing temperature was helpful for the reaction. The SEM topography showed that more hollow structure was produced on the surface corncob, as acidic adsorbate solution could make the hydrolysis of cellulose, and increased the specific surface area, formatting more conductive adsorption conditions. In addition, the electrostatic attractions of the protonated corncob and the cation affinity of the oxygen containing functional groups could adsorb the anionic forms of Cr(VI) and the cationic forms of Cr(III). It is feasible to remove the Cr(VI) from aqueous solution by corncob.%Cr是人和动物所必需的微量元素，但工业废水中的高浓度的Cr会对人类健康和生态环境都会造成严重的危害。为探讨玉米芯对废水中Cr(VI)的吸附特性，以期为应用玉米芯处理含Cr废水提供理论依据，在本研究中设置了3项试验：不同pH条件下的吸附试验、等温吸附试验和热力学试验，并对吸附前后的玉米芯进行扫描与能谱分析，探究玉米芯作为吸附剂对水中Cr(VI)的吸附机理。结果表明：低pH有利于玉米芯对Cr(VI)的吸附，在pH为1.0左右时，玉米芯对Cr(VI)有最佳吸附效果，最高去除率可达94.35%，最大吸附量可达23.9440 mg·g-1；玉米芯对Cr(VI)的吸附过程符合Langmuir、Freundlich和Dubinin-Radushkevich等温吸附模型，但以Freundlich模型的拟合效果为最优，1/n为0.8875，表明玉米芯对Cr(VI)的吸附强度适中；D-R模型中E=3.1528 kJ·mol-1，表明该吸附主要为物理吸附过程；热力学参数ΔH为-0.2728 kJ·mol-1，ΔS为0.0143 kJ·mol-1·K-1，表示玉米芯对Cr(VI)的吸附是一个自发的放热过程，且升高温度有利于吸附过程的进行；通过扫描电镜可以看出玉米芯表面产生了较多空洞结构，可能是酸性吸附质溶液可以使纤维素水解，增大了玉米芯的比表面积，形成了更有利于吸附的条件；另外玉米芯质子化的静电作用以及含氧官能团对阳离子的亲和性分别对阴离子形式的Cr(VI)和被还原成阳离子的Cr(III)有吸附作用。这些原因促进了玉米芯对Cr的吸附。
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