摘要
以氯化镁和水玻璃为原料,采用水热法制备了氧化镁含量低于10%的新型硅镁胶MgO·6SiO2,讨论了体系pH值、水热时间和温度等因素对产物硅镁物质的量之比的影响,通过比表面积分析、电位滴定法对样品进行了表征,用亚甲基蓝溶液评价其吸附性能.结果表明,MgO·6SiO2的最佳制备条件为:调节pH值到9.5左右、水热12 h、水热温度110℃,pH为控制产物硅镁物质的量之比的决定性因素;硅镁胶MgO·6SiO2是多孔材料,比表面积为285 m2·g-1,表面零电荷点pHzpc为10.4;25℃时,对亚甲基蓝的最大吸附量可达151.52 mg·g-1,吸附过程符合Langmuir吸附模型.
A new magnesium silicate gel adsorbent MgO·6SiO2 was synthesized by hydrothermal method from sodium metasilicate and magnesium chloride hexahydrate. Different factors affecting the preparation,i.e. pH,reaction temperature and reaction time were studied. Surface area and pHZPCof the product were investigated by BET and potentiometric titration,respectively. The adsorption behavior for methylene blue was systematically investigated. Results indicated that the hydrothermal reaction was expected to proceed under 110℃ for 12 h and pH was the decisive factor for Si /Mg mole ratios. The surface area of MgO·6SiO2 was 285 m2·g-1 and its pHZPCoccured around 10.4. At298K,the maximum adsorption capacity for methylene blue was 151.52 mg·g-1and the adsorption process was fitted to Langmuir isotherm.
出处
《环境化学》
CAS
CSCD
北大核心
2014年第6期985-991,共7页
Environmental Chemistry
基金
教育部博士点专项基金(20090132110009)资助
