以小麦壳为基质的生物吸附材料的制备及其用于处理三苯甲烷类染料废水的研究

Preparation of Wheat Hulls-based Bioadsorption Material and Its Application in the Treatment of Triphenylmethane Dye Wastewater

以农业废弃物小麦壳为基质,使用柠檬酸对其进行化学改性制备出一种新型阳离子生物吸附材料,并利用扫描电镜、傅里叶红外光谱和X射线光电子能谱对所制备的材料进行表征分析。研究了该生物吸附材料对三苯甲烷类阳离子染料(甲基紫和孔雀石绿)的静态吸附行为,讨论吸附剂投加量、pH和吸附时间等条件的影响,并对其吸附机理进行探讨。结果表明:柠檬酸改性小麦壳生物吸附材料对甲基紫和孔雀石绿的去除率随着吸附剂用量增加而提高;随着pH值的升高去除率升高;吸附过程符合Langmuir等温吸附模型,吸附过程主要由化学吸附控制,单分子层最大吸附容量分别达到了1 250.00 mg·g^(-1)和1 666.67 mg·g^(-1),比改性前材料的吸附容量分别提升了3.7倍和3.3倍。

A new cationic biosorption material was prepared using agricultural waste wheat hulls as substrate by chemical modification with citric acid. And the prepared material was characterized and analyzed by scanning electron microscopy, Fourier infrared spectroscopy and X-ray photoelectron spectroscopy. The static adsorption behavior of the biosorption materials on the cationic dyes of triphenylmethane(methyl violet and malachite green) was investigated.The effects of the conditions of adsorbent dosage, pH and adsorption time on the dyes removal were discussed,and the adsorption mechanism was explored. The results showed that the removal rates of methyl violet and malachite green by citric acid modified wheat shell biosorption increased with the increase of adsorbent dosage;the removal rate increased with the increase of p H value;the adsorption process was in accordance with the Langmuir isothermal adsorption model, and the adsorption process was mainly controlled by chemisorption. The maximum adsorption capacities of the single molecular layer reached 1250.00 mg·g^(-1)and 1666.67 mg·g^(-1)respectively, which were 3.7 and 3.3 times higher than the adsorption capacities of the pre-modified material.