聚丙烯酸/羟基磷灰石复合吸附剂对Pb(Ⅱ)的吸附行为  

On the adsorption behavior of poly(acrylicacid)/hydroxyapatite composite absorbent for Pb(Ⅱ)

作　　者：王金磊[1,2] 王爱勤[1] 

机构地区：[1]中国科学院兰州化学物理研究所,兰州730000 [2]中国科学院研究生院,北京100039

出　　处：《安全与环境学报》2009年第2期29-32,共4页Journal of Safety and Environment

基　　金：国家自然科学基金项目(20877077);甘肃省科技厅科技支撑项目(0804GKCA03A)

摘　　要：以部分中和的丙烯酸(AA)和羟基磷灰石(HP)为原料,通过自由基聚合反应合成聚丙烯酸/羟基磷灰石(PAA/HP)复合吸附剂,研究溶液pH值、吸附时间、Pb(Ⅱ)初始浓度及HP含量对PAA/HP吸附性能的影响。结果表明,PAA/HP复合吸附剂的吸附量先随溶液pH值及Pb(Ⅱ)初始浓度的增加而增大,随后趋于恒定。30℃、pH=6.0、Pb(Ⅱ)初始浓度0.01 mol/L条件下,HP需6 h达到吸附平衡(平衡吸附量为99 mg/g),而PAA/HP复合吸附剂(HP质量分数为10%)只需15 min即可达到吸附平衡量(943 mg/g)的96%。当Pb(Ⅱ)初始浓度≥0.008 mol/L时,PAA/HP复合吸附剂的饱和吸附量随HP含量的增加而减小,但此时复合吸附剂的饱和吸附量高于PAA和HP饱和吸附量的平均值。HP及PAA/HP复合吸附剂对Pb(Ⅱ)的吸附过程均符合准二级动力学模型和Langmuir吸附等温模型。吸附机理分析表明,PAA/HP复合吸附剂对Pb(Ⅱ)的吸附主要是由于复合吸附剂中COO-基团与Pb(Ⅱ)的相互作用。研究表明,PAA/HP复合吸附剂可用于含Pb(Ⅱ)废水的处理。As a part of efforts oriented to extending the application of the composite organic-inorganic absorbents for sewage pollutants and reducing the consumption of petroleum-based polymers, this paper is aimed at studying the adsorption behavior and adsorption mechanism of a novel composite absorbent for Pb（II） from aqueous solution. By using partially neutralized acrylic acid （AA） and hydroxyapatite （HP） micropowder as raw materials, ammonium persulphate （APS） as an initiator and N, N＇ - methylenebisacrylamide （MBA） as a erosslinker, we have synthesized a series of poly （acrylic acid）/hydroxyapatite （PAA/HP） composite absorbents through aqueous solution polymerization method. At the same time, we have systematically studied the factors influencing the Pb（II） absorption process, such as the initial pH value of the Pb（II） solution, adsorption time, initial Pb（II） concentration and HP content. Results of our research have shown that the adsorption capacity of PAA/HP composite absorbent tends to grow with the increase of the pH value and the initial concentration of the Pb（II） solution, with the maximum adsorption capacity obtained at pH = 6.0 and the initial Pb（II） concentration being 0.01 mol/L. Under the same conditions of 30 ℃ , initial Pb（II） concentration being 0.01 mol/L and pH = 6.0, HP needs 6 h to achieve its adsorption equilibrium （99 mg/g）, but PAA/HP （HP mass fraction is 10% ） composite absorbent reaches 96% of its equilibrium adsorp- tion capacity （943 mg/g） within 15 min. It was found that the ad- sorption capacity of PAA/HP composite absorbent would drop with the increase of the HP content at the high initial Pb （II） concentration （≥0.008 tool/L）. However, the adsorption capacity of PAA/HP was higher than the average of those of PAA and HP. Furthermore, we have also studied the adsorption kinetics and isotherms, discovering that all the sorption processes for HP and composite absorbents tend to follow the pseudo-second-order equ

关 键 词：环境工程 吸附 羟基磷灰石 复合吸附剂 铅离子 

分 类 号：X703.1[环境科学与工程—环境工程]