摘要
目的:探讨蛤蜊壳羟基磷灰石(HA)对铅的吸附性能。方法:以废弃蛤蜊壳为原料,在常温下运用沉淀法制备羟基磷灰石,通过X射线衍射(XRD)、扫描电子显微镜(SEM)及红外光谱(FTIR)表征产物的晶相组成、形貌及化学组成等,并采用模拟Pb2+溶液,考察时间、pH值、温度及初始Pb2+质量浓度对吸附效果的影响,从动力学和热力学角度探讨其吸附规律。结果:在pH3.0时,吸附效果最好,酸性环境有利于吸附,随着pH值的增大吸附容量逐渐降低;反应30min时基本达到吸附平衡;吸附容量随着初始溶液Pb2+质量浓度的增大而增大,高温有利于吸附反应的进行。结论:以蛤蜊壳为原料制备的羟基磷灰石对Pb2+有良好吸附效果,其吸附规律可以用Langmuir吸附模型描述,符合拟二级动力学模型,是一个自发的吸热反应。
Purpose： To investigate the adsorption capacity of hydroxyapatite prepared from clam shell for Pb2＋.Methods： Hydroxyapatite was prepared from clam shell by precipitation method under room temperature,and its crystal phase composition,morphology and chemical composition were characterized by employing X-ray diffraction（XRD）,scanning electron microscopy（SEM）,Fourier transform infrared spectroscopy（FTIR）.Adsorption of Pb2＋ solution models by the hydroxyapatite adsorbent was investigated with respect to various parameters such as adsorption time,pH,temperature and initial Pb2＋ concentration and the adsorption kinetics and thermodynamics were also explored.Results： The best adsorption capacity was found at pH 3.0.An acidic environment favored Pb2＋ adsorption,and the adsorption capacity of hydroxyapatite was gradually reduced with increasing pH.The adsorption process reached equilibrium in 30 min.The adsorption capacity was directly proportional to initial Pb2＋ concentration.Higher temperatures were favorable for the adsorption reaction.Conclusion： The hydroxyapatite prepared in this study has good adsorption capacity for Pb2＋,and the adsorption process can be described by the Langmuir model and follows pseudo-second-order kinetic equation as a spontaneous endothermic process.
出处
《食品科学》
EI
CAS
CSCD
北大核心
2013年第13期39-44,共6页
Food Science
基金
"十二五"国家科技支撑计划项目(2012BAD28B05)
