摘要
研究超临界环境中物质在吸附剂颗粒中的动力学行为十分关键.用Langmuir吸附模型、修正的Langmuir等温吸附模型及Freundlich吸附模型对实验数据进行了拟合,结果表明这3个模型都能较好地拟合超临界CO2中介孔基材SBA-15对前驱物AgNO3和Cu(NO3)2的吸附,其中Freundlich模型拟合误差最小.在此基础上,建立了基材颗粒内部吸附动力学模型,基于质量平衡微分方程,使用Polymath软件对吸附的平衡浓度及平衡时间进行模拟,与实验测定结果吻合良好.采用修正的Langmuir模型拟合吸附量与浓度的关系,结合动力学模型进行模拟计算可以较好地描述介孔氧化硅在超临界氛围中对无机盐的吸附行为.
Kinetics study of precursor adsorbed on mesoporous material in supercritical supercritical fluid deposition process. The thermodynamic adsorption models including fluid is very important for Langmuir model, modified Langmuir model and Freundlich model were used to fit the experimental data about the system of Cu (NO3)2 (adsorbate)and SBA-15(adsorbent) as well as AgNO3 (adsorbate) and SBA-15 (adsorbent) in scCO2 The three models fit the experimental data well and Freundlich model gave the smallest error. In addition, the kinetics model of adsorption in the particles of substrates was established based on the mass balance differential equation. The equation was solved using Polymath and the simulation results including the equilibrium concentration and equilibrium time were consistent with the experimental data. It was found that the simulating results were closer to the experimental data when using Modified Langmuir model to describe the relationship between the amounts adsorbed and the equilibrium concentration in order to solve the differential equation for the kinetic model.
出处
《应用科技》
CAS
2011年第12期50-54,共5页
Applied Science and Technology
基金
国家自然科学基金资助项目(20976028)