Fluorescent clays—Similar transfer with sensitive detection

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Vol. 174; no. 1; pp. 482 - 488
• Main Authors: Gitis, Vitaly, Dlugy, Christina, Ziskind, Gennady, Sladkevich, Sergey, Lev, Ovadia
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier B.V 15-10-2011; Elsevier
• Subjects: adsorption; Applied sciences; Aquifers; Chemical engineering; clay; Decontamination. Miscellaneous; dyes; Exact sciences and technology; fluorescence; MMT; montmorillonite; polluted soils; Pollution; Residence time distribution; Rhodamine 6G; sand; Soil and sediments pollution; Subsoil; Turbidity; Subsoil; Residence time distribution; MMT; Rhodamine 6G; Turbidity; Dyes; Montmorillonite; Adsorption capacity; Fluorescence; Soil pollution; Aquifers; Transport process; Dilution; Colloid particle
• ISSN: 1385-8947; 1873-3212
• DOI: 10.1016/j.cej.2011.08.063

► Two orders of magnitude higher sensitivity in detection of turbidity particles with a new tool—dyed intercalated clays. ► Organic matter and clays do not compete for sites but restructure the porous media for better accumulation. ► Reduction in colloidal turbidity may not be the correct target for improving the tertiary treatment. ► Fluorescent-marked colloids are useful in analysis of transport of pathogens and organic matter in subsoils.
The significant probe dilution is one of the reasons to use soluble dyes and concentrated ion solutions for studies of colloid transport in subsoils and aquifers. We studied the clay transport in sand columns with Rhodamine 6G-intercalated montmorillonite (MMT). Our MMT-R exhibited transfer properties similar to the non-dyed clays but was detectable starting from 1
ppb by fluorescence and only from 0.5
ppm by turbidity. More contaminated soil adsorbed the MMT-R better than the pure one and therefore the reduction of influent turbidity may have the unintended effect of decreasing soil adsorption capacity.