氧化石墨烯/二氧化硅复合材料的制备及吸附性能

Preparation and adsorption properties of graphene oxide/silica composite

以改进的Hummers法制备的氧化石墨烯溶液为原料,十六烷三甲基溴化铵为模板剂,正硅酸乙酯为硅源,采用软模板法制备了氧化石墨烯/二氧化硅复合材料。借助红外光谱仪、扫描电子显微镜、X射线衍射仪对样品的物质结构和微观形貌进行分析表征。以亚甲基蓝模拟染料废水,石墨烯/二氧化硅复合材料为吸附剂,研究其在不同吸附时间、反应温度、ρ(亚甲基蓝)、吸附剂投加量、体系pH值下,对体系吸附量和去除率的影响。结果表明,复合材料出现了C-O-Si的特征峰,说明石墨烯与二氧化硅复合成功;且复合材料在温度为35℃,搅拌时间为90 min,pH=4,ρ(亚甲基蓝)=5 mg/L,投加量为50 mg时吸附性能最好,吸附量为22.75 mg/g,去除率为91%。

The graphene/silica composite was prepared by soft template method with the graphene oxide solution prepared by improved Hummers method as raw material,the cetyltrimethylammonium bromide as template and the TEOS as silicon source.The material structure and micro morphology of the samples were characterized by infrared spectrometer,scanning electron microscope and X-ray diffractometer.The effects of adsorption time,reaction temperature,methylene blue concentration,adsorbent dosage and system pH on the adsorption capacity and removal efficiency of graphene/silica composite were studied.The results show that there is a characteristic peak of C-O-Si in the composite,which indicates that graphene and silica are successfully compounded.When the temperature is 35 ℃,the stirring time is 90 minutes,the pH is 4,the methylene blue concentration is 5 mg/L,and the dosage is 50 mg,the composite has the best adsorption performance,the adsorption capacity is 22.75 mg/g,and the removal rate is 91%.