Ataei-Germi Taher, Nematollahzadeh Ali
Chemical Engineering Department, University of Mohaghegh Ardabili, P.O. Box 179, Ardabil, Iran.
Chemical Engineering Department, University of Mohaghegh Ardabili, P.O. Box 179, Ardabil, Iran.
J Colloid Interface Sci. 2016 May 15;470:172-182. doi: 10.1016/j.jcis.2016.02.057. Epub 2016 Feb 27.
Bimodal meso/macro-porous silica microspheres (MSM) were synthesized by a modified sol-emulsion-gel method and then the surface was coated with polydopamine (PDA) nano-particles of 39nm in size. Focusing on the encouraging properties of the synthesized adsorbent, such as high specific surface area (612.3m(2)g(-1), because of mesopores), fast mass transfer (0.9-2.67×10(-3)mLmin(-1)mg, because of macropores), and abundant "adhesive" functional groups of PDA, it was used for the removal of methylene blue (MB) from aqueous solution in a fixed-bed column. The effect of different parameters such as pH, initial concentration, and flow rate was studied. The results revealed that an appropriate sorption condition is an alkaline solution of MB (e.g., pH 10) at low flow rate (less than 5mLmin(-1)). Furthermore, the compatibility of the experimental data with mathematical models such as Thomas and Adams-Bohart was investigated. Both of the models showed a good agreement with the experimental data (R(2)=0.9954-0.9994), and could be applied for the prediction of the column properties and breakthrough curves. Regeneration of the column was performed by using HCl solution with a concentration of 0.1M as an eluent.
采用改进的溶胶-乳液-凝胶法合成了双峰介孔/大孔二氧化硅微球（MSM），然后在其表面包覆了尺寸为39nm的聚多巴胺（PDA）纳米颗粒。鉴于合成吸附剂具有诸如高比表面积（由于介孔，为612.3m²g⁻¹）、快速传质（由于大孔，为0.9 - 2.67×10⁻³mLmin⁻¹mg）以及PDA丰富的“粘性”官能团等令人鼓舞的性能，将其用于固定床柱中从水溶液中去除亚甲基蓝（MB）。研究了不同参数如pH值、初始浓度和流速的影响。结果表明，合适的吸附条件是低流速（小于5mLmin⁻¹）下MB的碱性溶液（例如，pH 10）。此外，还研究了实验数据与托马斯和亚当斯-博哈特等数学模型的兼容性。这两个模型均与实验数据显示出良好的一致性（R² = 0.9954 - 0.9994），并且可用于预测柱性能和穿透曲线。使用浓度为0.1M的HCl溶液作为洗脱剂对柱进行再生。
