(1. 綠色化工過程教育部重點實驗室(武漢工程大學(xué))，武漢 430074；
2. 武漢工程大學(xué) 化工與制藥學(xué)院，武漢 430074)
摘 要: 為從高放廢液中分離富集鈀Pd(II)，考察纖維狀吸附材料Smopex？-102 FG對Pd(II)的靜態(tài)吸附行為，研究HNO3濃度、接觸時間、初始金屬離子濃度、溫度對Pd(II)吸附行為的影響，并考察吸附過程的動力學(xué)和熱力學(xué)。結(jié)果表明：在研究條件下，Smopex？-102 FG對Pd(II)的吸附分配系數(shù)Kd隨HNO3濃度的減小而逐漸增加，在HNO3濃度為0.001 mol/dm3時，分配系數(shù)Kd為142.0 cm3/g。Smopex？-102 FG吸附Pd(II)的動力學(xué)過程迅速，20 min即達到平衡狀態(tài)，且平衡吸附率(R)皆在70%以上，吸附動力學(xué)符合擬一階和擬二階動力學(xué)模型，理論平衡吸附量與實驗值(Qe=19.82 mg/g)基本吻合。Weber-Morris粒內(nèi)擴散模型表明，Pd(II)在纖維狀吸附材料Smopex？-102 FG的表面和顆粒內(nèi)的擴散共同控制吸附速率。與此同時，隨著初始金屬離子濃度的增大，Smopex？-102 FG對Pd(II)的平衡吸附量呈線性增加，而其對Pd(II)的吸附率卻隨之減小，吸附過程遵循Freundlich等溫吸附模型，為優(yōu)惠吸附。從熱力學(xué)實驗結(jié)果可知，該吸附是自發(fā)吸熱過程，溫度升高有利于吸附過程的進行。靜態(tài)吸附實驗表明，纖維狀吸附材料Smopex？-102 FG對鈀離子表現(xiàn)出良好的吸附性能，是一種適用于處理高放廢液中Pd(II)的吸附材料。
關(guān)鍵字: 鈀；纖維狀吸附材料；高放廢液；靜態(tài)吸附；動力學(xué)；熱力學(xué)
（1. Key Laboratory of Green Chemical Process (Wuhan Institute of Technology), Ministry of Education, Wuhan 430074, China;
2. School of Chemical Engineering & Pharmacy, Wuhan Institute of Technology, Wuhan 430074, China）
Abstract:Adsorption behavior of Pd(II) on fibrous Smopex？-102 FG adsorbent was investigated in order to separate and enrich Pd(II) from simulated high level liquid waste. Effects of HNO3 concentration, contact time, initial metal ions concentration and temperature on adsorption of Pd(II) using Smopex？-102 FG were investigated in HNO3 solution, as well as the adsorption characteristics from both kinetics and thermodynamics. The results show that distribution coefficient (Kd) of Pd(II) increases with the decrease of HNO3 concentration and Kd is 142.0 cm3/g in 0.001 mol/dm3 HNO3 solution. Pd(II) is absorbed with a rapid kinetics, and reached equilibrium state within 20 min, uptake ratio of Pd(II) is more than 70%. Adsorption behavior is fitted well with the kinetics model of pseudo-first-order and pseudo-second-order, controlled by the combination of film diffusion and intraparticle diffusion. Value of theoretical equilibrium adsorption capacity is similar to measured (Qe=19.82 mg/g). At the same time, the equilibrium adsorption amount increases but uptake ratio decreases with the increase of initial metal ion concentration. This adsorption process can be described well by Freundlich isothermal model which is a favorable adsorption. From adsorption thermodynamic parameters, it is a spontaneous endothermic process and high temperature is better for adsorption. Fibrous Smopex？-102 FG adsorbent will be a promising adsorbent using in partitioning of palladium from high level liquid waste.
Key words: palladium; fibrous adsorbent; high level liquid waste; static adsorption; kinetics; thermodynamics
