研究了胡萝卜渣对Cr6+的吸附作用及吸附过程的影响因素、热力学和动力学行为,结果表明:吸附率随胡萝卜渣粒径的减少而增大；Cr6+初始质量浓度相同时,吸附率随加入胡萝卜渣量的增加而增大,胡萝卜渣加入量相同时,吸附率均出现两次极小值且初始质量浓度为15 mg/L时吸附率最佳；正交试验结果表明:3个因素影响程度依次为温度＞pH＞时间,最佳吸附条件为溶液pH2、温度60℃、浸泡时间10h；吸附等温线结果表明:胡萝卜渣对Cr6+的吸附以单分子层吸附占优势,Freundlich吸附等温式吸附热力学行为,吸附为吸热过程,胡萝卜渣对Cr6+的吸附热为53.6 kJ/mol；吸附动力曲线结果表明:二级动力学模型能较好地描述胡萝卜渣对Cr6+的吸附动力学行为.%The paper studied the adsorption of Cr6+ by carrot pomace, the influence factors, the thermodynamic and kinetic behaviors of the adsorption process. The results showed that the adsorption rate increased as the particle diameter of the carrot pomace was reduced; the adsorption rate increased with the increase of the amount of the carrot pomace under the condition of same Cr6+ initial concentration; the adsorption rate had two minimum values under the condition of same addition amount of carrot pomace, and had the largest value when the Cr6+ initial concentration was 15 mg/L. Orthogonal experiments showed that the order of the influence degree of the three factors was temperature, pH and time; and the optimum adsorption conditions were as follows: pH 2.0, temperature 60 ℃ and soaking time 10 hours. The result of adsorption isotherm showed that monolayer adsorption was predominant; the adsorption isotherm fit the thermodynamic behavior of Freundlich adsorption; the adsorption process was the endothermic process; and the adsorptive heat of Cr6+ was 53.6 kJ · mol-1. The adsorption kinetic curve showed that the second-order kinetic model could well describe the adsorption kinetic behavior of carrot pomace.
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