Wen-bo Liu,Guan-ning Cui,Hu Wang,Dong-mei Zhang,Rui-xue Wu,Ling Li,Xia Zhang,Yu-hua Fan
Adsorption is considered as one of the eco-friendly methods to effectively remove pollutants from water environment. 1 , namely ([Zn 3 (dpcp) 2 (1,4′-bmib) 2 ] n , dpcp = 3-(3,5-dicarboxylphenoxy)-5-carboxylpyridine and 1,4′-bmib = 1,4-bis(2-methylimidazol-1-yl) butane), was synthesized under simple solvothermal method and characterized by XRD , PXRD , TGA , FTIR, BET and Zeta potential . The influence of temperature and pH of the solution and the dye initial concentration on the adsorption process of 1 was investigated using Congo red (CR) as the adsorption object. Pseudo second-order kinetics and Langmuir isotherms more accurately described the adsorption process of 1 . The maximum adsorption capacity measured in the adsorption experiment was about 262.2 mg g -1 . Thermodynamic studies showed that the entire adsorption process was spontaneous. In addition, 1 released the CR dye by a simple organic solvent (ethanol solution of NaOH) and exhibited stable and high adsorption performance over 5 cycles. The subtle hydrogen bond between 1 and the dye promotes its selective adsorption of CR.
Nowadays, the reduction of dye contaminants in the aquatic environment has attracted widespread research attention. In this work, a novel mesoporous carbon nanospheres (MCNs)-based material as an adsorbent for dye removal was achieved by the carbonization of a composite of sucrose and aluminum sulfate without involving any hazardous activators. The as-obtained MCNs were analyzed by TG, XRD, FESEM, TEM, Raman, BET and XPS, meanwhile the batch experiments of Congo red (CR), Malachite green (MG) and Methylene blue (MB) on the MCNs were conducted to explore the impact of adsorption conditions on the adsorption process, respectively. Results show that the MCNs exhibit a uniform spherical morphology as well as partially graphitic structure with a large surface area of 449.25 m 2 /g, a relatively narrow pore size distribution and a high pore volume of 0.57 cm 3 g −1 . The unique porous structure of the MCNs endows it with high adsorption capabilities for dyes, including CR (1726.60 mg g −1 ), MG (980.55 mg g −1 ) and MB (708.82 mg g −1 ), suggesting its high adsorption capability for both anionic and cationic dyes. Meanwhile, the adsorption process is demonstrated to follow the Langmuir model and pseudo-second-order kinetic model, respectively, and the main adsorption mechanisms may involve pore filling, π-π conjugation, electrostatic attraction and hydrogen bonding. Furthermore, the as-synthesized adsorbent displays good recyclability performance for remaining relatively high sorption performance even after five regeneration cycles.
Melamine formaldehyde resin based on graphene oxide (GO@MF) was successfully prepared, then, Fe3O4 was introduced to synthesis a magnetic composite, which used for the adsorption of anionic dyes. The Fe3O4/GO@MF was characterized by SEM, FTIR, XRD and VSM. Adsorption behaviors affected by concentration, contact time, pH and ionic strength of the as-prepared composites for Congo red (CR) and methyl blue (MB) were systematically explored and discussed. The equilibrium adsorption data of CR and MB accorded better with the Langmuir model and the Freundlich model, respectively, while there kinetics adsorption data both fitted the pseudo-second-order model. The kinetic and equilibrium parameters were also calculated. The maximum adsorption capacities calculated by Langmuir model of CR and MB were 257.07 mg g−1, 418.41 mg g−1, respectively and the equilibrium adsorption capacities calculated by pseudo-second order were basically same to the experimental results. The adsorption capacities of CR and MB affected by the pH were significant which may due to the protonation or deprotonation of amino and secondary amino groups. In addition, the introduction of Fe3O4 into GO@MF composited endued it with excellent magnetic separation property. Fe3O4/GO@MF exhibited well adsorption selectivity on anionic acid dyes and stabilized regeneration performance.
危险品化学品经营许可证（带存储）