Adsorption Kinetics of Dibenzofuran in Activated Carbon Packed Bed

The adsorption of dibenzofuran （DBF） on three commercial granular activated carbons （GAC） was investigated to correlate the adsorption equilibrium and kinetics with the morphological characteristics of activated carbons. Breakthrough experiment was conducted to determine the isotherm and kinetics of dibenzofuran on the activated carbons. All-the experiment runs were performed in a fixed bed with a process temperature of 368 K. The effects of adsorbent morphological properties on the kinetics of the adsorption process were studied. The equilibrium data are found satisfactory fitted to the Langmuir isotherm. An intraparticle diffusion model based on the obtained Langmuir isotherm was＇developed for predicting the fixed bed adsorption of dibenzofuran. The result indicated that this model fit all the breakthrough curves well. The surface diffusion coefficients of dibenzofuran on the activated carbon are calculated, and a relationship with the microporosity is found. As it was expected, the dibenzofuran molecule finds more kinetic restrictions for the diffusion in those carbons with narrower pore diameter.

Development of Ni_(x)/Mg_(1-x)-MOF-74 for highly efficient CO_(2)/N_(2) separation

To enhance the separation selectivity of Mg-MOF-74 towards CO_(2) in a CO_(2)/N_(2) mixture,a series of Mg-MOF-74 and Ni_(x)/Mg_(1-x)-MOF-74 adsorbents were prepared by solvothermal synthesis in this paper.It was found that the adsorption capacity of Mg-MOF-74 for CO_(2) could be effectively increased by optimizing the amount of acetic acid.On this basis,the bimetal MOF-74 adsorbent was prepared by metal modification.The multi-component dynamic adsorption penetration analysis was utilized to examine the CO_(2) adsorption capacity and CO_(2)/N_(2) selectivity of the diverse adsorbent materials.The results showed that Ni0.11/Mg0.89-MOF-74 showed a CO_(2) adsorption capacity of 7.02 mmol/g under pure CO_(2) atmosphere and had a selectivity of 20.50 for CO_(2)/N_(2) under 15% CO_(2)/85%N_(2) conditions,which was 10.2% and 18.02% higher than that of Mg-MOF-74 respectively.Combining XPS,SEM and N_(2) adsorption-desorption characterization analysis,it was attributed to the effect of the more stable unsaturated metal sites Ni into the Mg-MOF-74 on the pore structure and the synergistic interaction between the two metals.Density Functional Theory(DFT)simulations revealed that the synergistic interaction between modulated the electrostatic potential strength and gradient of the material,which was more favorable for the adsorption of CO_(2) molecules with small diameters and large quadrupole moment.In addition,the Ni0.11/Mg0.89-MOF-74 showed commendable cyclic stability,underscoring its promising potential for practical applications.