1. BTEX Sorption by Organo-Clays: Cosorptive Enhancement and Equivalence of Interlayer Complexes W. F. Jaynes and G. F. Vance Soil Science of America Journal 60:1742-1749 (1996) Anthony G. Benoit Lucas Hellerich

2. General Objectives of Organo-clay Research A clay mineral containing metal ions, such as Ca 2+, in the interlayer space is exchanged with organic cations. The resulting organo-clay compound has a greatly increased capacity to sorb organic contaminants from various water and vapor phase sources. Research is underway to elucidate the properties and applications of organo-clays.

3. What is a Clay ? Sposito & Grasso, in press

4. Organic Cations Used in Study Table 1: Chemical Formulas and molecular weights (MW) of organic cations used in the study Taken from Jaynes and Vance, 1996 Designation Cation NameFormulamw CDTMAcyclododecyltrimethylammoniumC 15 H 32 N + 226 DTMAdodecyltrimethylammoniumC 15 H 34 N + 228 HDTMAhexadecyltrimethylammoniumC 19 H 42 N + 285 DDDMAdidodecyldimethylammoniumC 26 H 56 N + 383 DODMAdioctadecyldimethylammoniumC 38 H 80 N + 551

5. BTEX Mixture Up to 24  L of BTEX mixture was added to 25 mL of distilled water: These proportions are consistent with 92 octane unleaded gasoline. Table 2: Contstituents of the BTEX mixture with C w sat values.

6. There was no relationship between surface area and sorption Data from Jaynes & Vance, 1996