One-step synthesis of high capacity mesoporous Hg2+ adsorbents by non-ionic surfactant assembly

We report the first example of a one-step preparation route towards high capacity mesostructured heavy metal ion adsorbents with uniform mesopore diameters. The synthesis approach involved the co-condensation of TEOS and 3-mercaptopropyltrimethoxysilane in the presence of structure-directing non-ionic Triton-X100 surfactant micelles. One such material, denoted MP(2)-MSU-2, had a uniform pore diameter distribution centered at 28 Angstrom and a Hg2+ loading capacity of 2.3 mmol/g, making its effectiveness for mercury ion trapping comparable to that of the highest capacity materials previously reported. The total access of the Hg2+ ions to every complexation site in the adsorbents was also demonstrated. Treating the Hg-loaded adsorbents with concentrated HCl was found to remove the bound mercury ions and regenerate the material for further adsorption. (C) 2000 Elsevier Science B.V. All rights reserved.