热改性高硅煤矸石对甲基橙的吸附性能研究

Study on Adsorption Properties of Methyl Orange by Thermal Modified High Silicon Coal Gangue

用煅烧的方法对高硅煤矸石进行热改性,制备出热改性煤矸石。采用吸附热力学模型拟合热改性煤矸石对甲基橙的吸附特性,并结合XRD和SEM分析表征手段探讨了其吸附机制。结果表明:热改性煤矸石结构变得疏松,孔隙率增加。在650℃煅烧2 h得到的热改性煤矸石对甲基橙的吸附量和去除率最大,其最佳吸附条件为:吸附温度为25℃(常温),吸附时间为1 h,热改性煤矸石加入量为6 g·L^(-1),甲基橙初始质量浓度为50 mg·L^(-1)。热改性煤矸石对甲基橙溶液的吸附符合Langmuir模型和Freundlich模型,但更适合用Langmuir模型进行表述,属于单分子层吸附。热改性煤矸石对甲基橙的吸附体系稳定性较差,但吸附过程易于进行。

Thermal modified coal gangue with high silicon was prepared by calcining method.The adsorption thermodynamics model was used to fit the adsorption characteristics of methyl orange by thermal modified coal gangue,and the adsorption mechanism was discussed by XRD and SEM analysis.It was found that the structure of thermal modified coal gangue became loose and the porosity increased.The thermal modified coal gangue obtained by calcination at 650℃for 2 h had the highest adsorption capacity and removal rate of methyl orange.The optimal adsorption conditions were as follows:the adsorption temperature was 25℃,the adsorption time was 1 h,the addition amount of thermal modified coal gangue was 6 g·L^(-1),and the initial mass concentration of methyl orange was 50 mg·L^(-1).The adsorption of methyl orange solution by thermal modified coal gangue conformed to Langmuir model and Freundlich model,but it was more suitable for Langmuir model,which belonged to single molecular layer adsorption.The stability of the adsorption system of methyl orange by thermal modified coal gangue was poor.But the adsorption process was easy to carry out.