Acta Phys. -Chim. Sin. ›› 2012, Vol. 28 ›› Issue (06): 1432-1438.doi: 10.3866/PKU.WHXB201203151

• CATALYSIS AND SURFACE SCIENCE • Previous Articles     Next Articles

Synthesis of Hydrophobic Porous Silica for Removal of Organic Contaminations from Water

SUN Tao, GUO Yue, LI Wen-Cui, LU An-Hui   

  1. State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Faculty of Chemical, Environmental and Biological Science and Technology, Dalian University of Technology, Dalian 116024, Liaoning Province, P. R. China
  • Received:2011-12-15 Revised:2012-03-09 Published:2012-05-17
  • Contact: LU An-Hui E-mail:anhuilu@dlut.edu.cn
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (20873014, 21073026) and Program for New Century Excellent Talents in Universities of China (NCET-09-0254).

Abstract: A hydrophobic porous silica material was successfully synthesized using sodium silicate as silica source, hydrochloric acid as catalyst, and trimethylchlorosilane (TMCS) as a surface modifying agent, through sol-gel and surface modification processes. The structure and properties of the fabricated porous silica were analyzed by Fourier-transform infrared (FTIR) spectroscopy, contact-angle analyzer, liquid N2 adsorption, and scanning electron microscopy (SEM). The porous silica displayed a hierarchical porous structure and was super-hydrophobic, with contact angle as high as 156°. Specific surface area and pore volume were determined to be 566 m2·g-1 and 2.28 cm3·g-1, respectively. Moreover, the porous silica could adsorb up to 14 times its own mass of toluene, gasoline, diesel, and lube oil. The abundant mesopores and macropores allowed adsorption saturation to be reached within several minutes. In addition, the porous silica was extremely hydrophobic in gasoline-water mixture and thus preferentially adsorbed organic compounds other than water. This is an important requisite of good recyclability. It was verified that, following extraction with n-hexane, the regenerated porous silica retained its initial adsorption capacity. This porous silica, with good selectivity and excellent regeneration capability for oil removal, could find novel applications in the adsorption and separation of organics from polluted water.

Key words: Porous silica, Hydrophobic property, Adsorption, Organic contamination, Regeneration

MSC2000: 

  • O647