Applications humic materials

In this chapter, we present the theory and results of measurements on humic acid fractions using fluorescence techniques. The fluorescence techniques are attractive for this application because of the natural fluorescence of humic materials, the hi sensitivity of fluorescence detection, and the ability to directly observe the morphology of the molecule in aqueous solutions without the need for drying or applying harsh chemical conditions. Several interesting types of information are obtained from fluorescence measurements ... 

Environmental applications of FIFFF have been carefully collected in a review by Gimbert et al. [35]. Separations of nanoparticles belong to the FIFFF tradition and this sector has recently found new, fully deserved impulse for microparticle separations. The FIFFF technique has been applied to analyze humic material and submicron Fe colloids. Coupled with ICP-MS, FIFFF has been applied to detect the major and trace element chemistry of aquatic colloids in groundwaters and to determine the trace element distribution in soil and compost-derived humic and colloidal fractions in municipal wastewater. Recently, the ICP-AES has also been proposed as a specific detector for FIFFF to analyze inorganic nanoparticles (Figure 12.12). 

Rice, J. A. (2008). Applications of fractals in the study of humic materials. In Bio-Physical Chemistry of Fractal Structures and Process in Environmental Systems, Senesi, N., and Wilkinson, K., eds., IUPAC Series on Analytical and Physical Chemistry of Environmental Systems, Vol. 11, John Wiley Sons, Chichester, pp. 221-238. 

Ultrafiltration (UF) is a technique that has been widely used for fractionation of HS on the basis of molecular size differences (Janos, 2003). Its application to quantify size and molecular weight characteristics of aquatic humic materials is reviewed in detail by Burba et al. (1998) and Guo and Santchi (2007). 

In 1989, the first applications of multidimensional NMR were applied to humic substances (Buddrus et al., 1989).This study involved the application of 13C detected J-resolved (J-Res) spectroscopy. The study was successful in that it showed multidimensional NMR was applicable to the study of humic substances. However, in 1989 the lack of various modern experiments and the corresponding hardware (mainly probes fitted with pulse field gradients) made applying NMR to humic materials very challenging. In 1997, Simpson et al. demonstrated that the more sensitive inverse-detected NMR experiments were applicable to NOM (Simpson et al., 1997). In this manuscript COSY,TOCSY and HMQC were applied (Simpson et al.,... 

Bound triazine residues are very resistant to decomposition. Nine years after application of 14C-atrazine to soil, about 50% of the 14C was still present in the bound form in humic materials (Capriel et al., 1985). Of this bound 14C-atrazine, hydroxyatrazine, deethylhydroxyatrazine, and deisopropylhydroxyatrazine could be detected in measurable quantities. Khan and Behki (1990) conducted a laboratory study showing that a Pseudomonas spp. could release bound 14C residues from soil treated with 14C-atrazine. 

The study of Lovgren et al. (1987) provides an example of the application of a discrete functional group approach to model the complexation of aluminium with humic substances found in bog-water. The acid-base titration behaviour of the humic material found in Swedish bog-water was modelled as a diprotic acid with the following reactions and acid dissociation constants ... 

Perdue, E.M. and Lytle, C.R. (1983a) A critical examination of metal-ligand complexation models application to defined multiligand mixtures. In Aquatic and Terrestrial Humic Materials (eds Christman, R.F. and Gjessing, E.T.). Ann Arbor Science, Ann Arbor, MI, pp. 295-313. 

This last point is one of the most significant and challenging areas in the development of adsorption technology today, at least with respect to field applications of the technology. In one approach, adsorption data are modeled in term of target organics, treating other compounds such as humic material as an unspecified but... 

Some of the first NMR spectroscopic applications in humic substance research involved the use of NMR for the examination of soluble humic substances.(5) The information obtained from NMR spectra of humic and fulvic acids dissolved in alkaline or neutral aqueous solutions has been quite useful in characterizing the aromatic and aliphatic structures of these complex materials. In as much as humic materials are inherently complex, the spectra show only broad signals with some fine structure which can be related to specific methyl, methylene, methine, and aromatic/olefinic hydrogens. Because NMR spectroscopy contains inherently more structural information for humic substances, the use of NMR has been limited since much of the work conducted prior to 1987. This is... 

Application of the TMAH/Thermochemolysis Procedure to Humic Materials... 

Visser, S. A. (1983a). Application of Von Krevelen s graphical-statistical method for the study of aquatic humic material. Environ. Sci. Technol. 17, 412-417. 

R161 J. Zakrzewska, Z. Zujovic and D. Vucelic, Application of NMR Spectroscopy for Structural Studies of Lignins, Humic Materials and Oil Shales , p. Pl/291... 

Alberts, J. J. and Giesy J.P., Conditional stability constants of trace metals and naturally occurring humic materials Application in equilibrium models and verification with field data. In Aquatic and Terrestrial Humic Materials, R.F. Christman and E.T. Gjessing (Eds.),Ann Arbor Science Publishers, Ann Arbor, Ml, 1983, pp538. 

Perdue, M. P., and C. R. Lytle (1983), A Critical Examination of Metal-Ligand Complexation Models Application to Defined Multiligand Mixtures, in R. F. Christman and E. T. Gjessing, Eds., Aquatic and Terrestrial Humic Materials, Ann Arbor Science, Ann Arbor, MI, Chapter 14. 

The application of 15N NMR to the structural determination of humic material is noted in Chapter 3 (Section 3.2.4)... 

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