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摘要：将H-Beta用于处理含聚丙烯酰胺(PAM)的驱油废水,研究了PAM在H-Beta上的吸附动力学和热力学特征,并考察了吸附条件对吸附效果的影响.结果表明,吸附过程遵循准二级动力学模型;在低PAM初始浓度(100 mg · L^-1)时,吸附表观活化能>40 kJ · mol^-1,说明H-Beta对PAM的吸附以化学吸附为主;在高PAM初始浓度(200和500 mg · L^-1)时,吸附活化能降低,吸附向物理吸附转变.吸附等温线在低平衡浓度区符合Langmuir模型,25、40和50 ℃时的单层饱和吸附量分别达到70.2、76.9和90.9 mg · g^-1;在高平衡浓度区符合Freundlich模型,表现为多层吸附.吸附主要来自氢键作用,为自发的吸热过程.pH为2~4,吸附剂用量为5 g · L^-1时,具有更优的吸附效果.真实废水中油和盐类的存在对PAM在H-Beta上的吸附未产生不利影响.

Abstract：H-Beta molecular sieve was used to adsorb polyacrylamide (PAM) in oil field wastewater. The adsorption kinetics and thermodynamics of PAM on H-Beta and effects of different conditions on adsorption were investigated. The results showed that the adsorption kinetics can be well described by the pseudo-second-order kinetics model. At low initial PAM concentration (100 mg · L^-1), the apparent adsorption activation energy (E_a) was higher than 40 kJ · mol^-1, indicating chemical adsorption dominated. While E_a decreased at high PAM concentrations (200 and 500 mg · L^-1), suggesting physical adsorption was dominant in these conditions. Under low PAM equilibrium concentrations, the adsorption isotherms could be well fitted by Langmuir equation. The monolayer saturation adsorption capacity was 70.2 mg · g^-1 at 25 ℃, 76.9 mg · g^-1 at 40 ℃ and 90.9 mg · g^-1 at 50 ℃. Under high PAM equilibrium concentrations, the adsorption isotherms matched with Freundlich equation, indicating the multilayer adsorption. The adsorption was a spontaneous and endothermic process mainly caused by H-bonding. The optimal adsorption performance could be achieved under the conditions of pH value at 2~4 and adsorbent dosage at 5 g · L^-1.The adsorption performance of PAM on H-Beta was not affected by the oil and salts in the real PAM-containing wastewater.