高炉钛渣吸附废润滑油的动力学和热力学

Adsorption kinetics and thermodynamics of Ti-bearing blast furnace slag for waste lubricating oil

采用高炉钛渣作为吸附剂,以废润滑油中的酸性组分作为吸附质,利用液体石蜡和正辛酸配制模拟废润滑油,考察吸附剂投加量、吸附时间、搅拌转速和吸附质初始浓度等条件对吸附的影响,在此基础上进行了高炉钛渣吸附废润滑油的动力学和热力学研究。结果表明:高炉钛渣吸附废润滑油的动力学过程可用准二级动力学模型进行描述,吸附过程由液膜扩散和粒子内扩散共同控制;高炉钛渣吸附废润滑的过程更好的符合Langmuir吸附等温方程,具有单层吸附的吸附特征;热力学参数表明,高炉钛渣吸附废润滑油的吸附过程为自发进行的吸热过程,吸附过程受范德华力、氢键力和偶极间作用力的共同作用。

The influence of adsorbent dosage, adsorption time, agitation speed, and initial adsorbate concentra- tion on the adsorption effect of Ti-bearing blast furnace slag for waste lubricating oil （ simulated by liquid paraffin and n-caprylic acid） was analyzed, using the acidic component in waste lubricating oil as the adsorbate. On this basis, the adsorption kinetics and thermodynamics of Ti-bearing blast furnace slag for waste lubricating oil was investigated. Results indicate that the dynamic process of the adsorption of waste lubricating oil by Ti-bearing blast furnace slag can be described by the pseudo-second-order kinetics model, and that the adsorption process is controlled by liquid film and intra-particle diffusion. In addition, the adsorption process of Ti-bearing blast fur- nace slag for waste lubricating oil can be well described by the Langmuir isotherm equation, which has the char- acteristics of monolayer adsorption. Furthermore, the thermodynamic parameters show that the adsorption of waste lubricating oil by Ti-bearing blast furnace slag is a spontaneous endothermic process under the combined effect of the van der Waals force, the hydrogen bonding force, and the dipole force.