Fulvic adsorption effects

Rnauer, K. and Buffle, J. (2001). Adsorption of fulvic acid on algal surfaces and its effect on carbon uptake, J. Phycol., 37, 47-51. 

Using the aforementioned methodology, the electrode reaction of Mo(VI) has been studied in the presence of phenanthrohne and an excess of fulvic acids [105]. Both ligands exhibit a synergetic effect toward adsorption of the mixed complex of... 

In view of its importance, reductive dissolution of Fe oxides has been widely studied. Reductants investigated include dithionite, thioglycolic acid, thiocyanate, hydrazine, ascorbic acid, hydroquinone, H2S, H2, Fe ", tris (picolinato) V", fulvic acid, fructose, sucrose and biomass/bacteria (Tab. 12.3). Under the appropriate conditions, reductive dissolution may also be effected photochemically. As with protonation, the extent of reduction may be strongly influenced by ligand and proton adsorption on the oxide surface. 

Simeoni, M.A., Batts, B.D. and McRae, C. (2003) Effect of groundwater fulvic acid on the adsorption of arsenate by ferrihydrite and gibbsite. Applied Geochemistry, 18(10), 1507-15. 

Dissolved humic and fulvic acids can be isolated from the total DOC pool by adsorption onto resins as discussed by Aiken in Chapter 14 of this book. Muenster (1982) found that 77-86% of the DOC (measured by UV absorbance and organic carbon) adsorbed onto XAD resin at pH values of 2.0-3.0. Adsorption onto PVP resin was slightly less effective (70-76% at pH values of 2.0-3.0). These differences in adsorption efficiency may be explained by organic material other than humic substances being retained on these resins. 

Saito and Hayano (1979) published the results of a preliminary study of the fractionation of humic and fulvic acids with a Toyo Soda high-performance gel. They found that humic and fulvic acids were completely excluded from the gel pores by electrostatic effects when distilled water was used as an eluent. When the column was eluted with QAM NaCl, this exclusion was not observed, and they found no evidence of adsorption of the humic substances on the gel. From these results, the authors suggested that this gel... 

Staunton, S., and Roubaud, M. (1997). Adsorption of radiocaesium on montmorillonite and illite effect of charge compensating cation, ionic strength, concentration of potassium, caesium and fulvic acid. Clays Clay Miner. 45, 251-260. 

Randtke, SJ. andjepse, C.P. (1982). Effects of salts on activated carbon adsorption of fulvic acid./. Am. Water Works Assoc., 74, 84—93. 

Amal R., Raper J.A., Waite T.D. (1992), Effect of fulvic acid adsorption on the aggregation kinetics and structure of hematite particles. Journal of CoUoid and Interface Science, 151,1, 244-257. 

Studies of the adsorption of fulvic acids by clays are very limited but apparently the non-polysaccharide portion behaves much like humic acids. According to Evans and Russell (1959) the order of effectiveness of fulvic acid adsorption on bentonite was acid > Ca > Mg > K and Na systems. Only a small proportion of the fulvic acid carbon, as in the case of humic acid carbon, was adsorbed. Kaolin was also an active adsorbent, the order being acid > Ca > K, as in bentonite systems. 

Pignatello, J. J., S. Kwon, and Y. Lu. 2006. Effect of natural organic substances on the surface and adsorptive properties of environmental black carbon (char) Attenuation of surface activity by humic and fulvic acids. Environmental Science Technology 40, no. 24 7757-7763. doi 10.1021/es061307m. 

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