聚丙烯酸钠在中空纤维超滤膜表面的吸附研究  

Adsorption Behavior of Poly (acrylic acid) Sodium on Hollow Fiber Ultrafiltration Membrane Surface

作　　者：曾坚贤[1] 叶红齐[1] 刘辉[1] 张赢超[1] 

机构地区：[1]中南大学化学化工学院

出　　处：《高校化学工程学报》2007年第4期563-568,共6页Journal of Chemical Engineering of Chinese Universities

基　　金：湖南省自然科学基金;湖南科技大学联合资助项目(05JJ40020);湖南省教育厅基金资助项目(05C170)

摘　　要：以KCl溶液为背景电解质液,测得聚砜中空纤维超滤膜等电点的pH值为2.9±0.1。当聚丙烯酸钠溶液pH值在等电点附近时,溶质在膜表面吸附量显著增大,导致膜通量迅速下降。研究了不同温度下膜表面吸附量随时间的变化,结果表明：吸附反应可用拟二级速率方程来描述,温度为293-308K时,速率常数在0.359-0.604m^2·g^-1·min^-1内递增。考察不同pH值和离子强度对吸附过程的影响可得：当pH值为2.6-9时,平衡吸附量由0.218下降至0.012g·m^-2;当离子强度为0.0-0.1mol·L/6-1时,平衡吸附量由0.218降低至0.154g·m^-2。进一步研究了平衡浓度对吸附量的影响,结果表明当聚丙烯酸钠浓度为0.05-5.0g·L^-1及pH≤4时,Langmuir吸附等温线对实验数据能较好地拟合,方程参数qm和b值的大小随膜表面吸附量的增大而增大。The adsorption behavior of poly（acrylic acid） sodium on hollow fiber ultrafiltration membrane （HFUM） surface was studied, It was found that, when KCI solution is used as background electrolyte solution, the pH value at the isoelectric point of polysulfone hollow fiber ultrafiltration membrane is 2.9±0.1, If the pH value of poly（acrylic acid） sodium solution is close to that of the isoelectric point of the HFUM, the membrane surface exhibits having high adsorption capacity to the solute, and membrane flux declines rapidly, The changes of adsorption capacity with time at various temperatures were investigated, The results indicate that the adsorption kinetics can be described by the pseudo-second-order rate model, and the rate constant is between 0,359 and 0,604 m2.g^-1·min^-1 when temperature is 293-308 K, Effects of pH value and ionic strength on the adsorption were studied, It was found that the equilibrium capacity decreases from 0.218 to 0,012 g·m^-2when pH varies from 2,6 to 9, and that decreases from 0,218 to 0,154 g·m^-2 when the ionic strength varies from 0,0 to 0.1 mol·L^-1, Moreover, effect of equilibrium concentration on the adsorption capacity was investigated, and results show that the Langmuir equation can be fit perfectly for the experimental data of the poly（acrylic acid） sodium solution with concentration of 0,05-5.0 g·L^-1 and pH≤4, and the values of equation parameters, qm and b, increase with increasing the adsorption capacity of membrane surface,

关 键 词：超滤 聚丙烯酸钠 吸附 流动电位 

分 类 号：TQ028.8[化学工程]