超(亚)临界水处理白酒糟制备活性炭

Preparation of Activated Carbon from Distiller’s Grains by Sub-and Supercritical Water

以白酒糟为原料,采用超(亚)临界水处理法来制备多孔碳材料,通过考察温度、压力、停留时间对活性炭性能的影响,探讨技术的可行性。结果表明,超(亚)临界水活化法可用来制备活性炭,在超临界状态(450℃,25Mpa,10min)下可制得活性炭,其对碘的吸附值为624mg·g^-1,对亚甲基蓝的吸附值为118mg·g^-1。利用所制备的活性炭对模拟印染废水进行吸附性能研究,结果表明其可用来作为吸附染料废水的吸附剂,对甲基橙的吸附率随着pH的升高而降低,随活性炭用量增加而升高。吸附符合Langmuir吸附等温式,吸附动力学可通过准二级动力学模型描述,吸附过程主要由化学吸附控制。

The activated carbon was prepared by sub- and supercritical water activation method with white distiller's grains as raw material. By examining the effects of temperature, pressure and residence time on the performance of activated carbon, the feasibility of the technology is discussed.The results show that the sub- and supercritical water activation method can be used to prepare activated carbon. In the supercritical state (450℃, 25 Mpa,10 min), better activated carbon can be obtained. The iodine adsorption value is 624 mg·g^-1 , and the methylene blue adsorption value is 118 mg·g^-1 .At the same time, the activated carbon was used to adsorb the methyl orange molecules in the simulated printing and dyeing wastewater.Experiments show that the activated carbon prepared by the experiment can be used as an adsorbent for adsorbing dye wastewater. The adsorption rate of methyl orange decreases with the increase of pH, and increases with the increase of the amount of activated carbon. The adsorption is in accordance with the Langmuir adsorption isotherm, and the adsorption kinetics can be described by a quasi-secondary kinetic model. The adsorption process is mainly controlled by chemical adsorption, which is exothermic.