An X-ray diffraction study of alkylammonium humate complexes

Abstract

By exchange of cations of different humates (synthetic, brown coal and compost humates) with an equivalent amount of long-chain organic cations, derivatives with the following alkylammonium ions were prepared: n-decyl, n-dodecyl, n-tetradecyl, n-hexadecyl and n-octadecyl ammonium ions. X-ray diffraction of the humic acids and the alkylammonium h umates revealed a behaviour similar to that of smectite-type clay minerals. The results seem to support the layer structure of humic substances. The layers of synthetic, brown coal and compost humate are about 0.60, 0.45 and 0.84 nm thick, and the bilayers of alkylammonium cations are bound to the carboxyl and phenolic hydroxyl groups. The chain tilt is 41-45 ~

Binding of cationic surfactants to humic substances

“…Previous studies performed on surfactant-HA interactions can be found in refs. [12,[20][21][22][23][24][25]. Koopal et al [12] and Adou et al [24] mention that humic acid is removed from the aqueous phase by forming neutral hydrophobic complexes with cationic surfactants.…”

Characterization of salt- and surfactant-containing sandy soil extracts by laser light methods

“…In our surfactant-containing system, either homogenous micelles (SDS-SDS, HS-HS) or mixed micelles (SDS-HS) can be formed (Tombácz et al, 1988) due to the solubilization process (Földényi et al, 2013;Senesi, 1993), which is caused here by the anionic surfactant. Mixed micelles are the result of interaction between the hydrophobic moieties of the surfactant and that of HS.…”

“…Humic substances (HS) are special and important components of natural organic matter (NOM) present in soil, water, and other geological deposits. Since HS molecules consist of an elongated hydrophobic portion with more anionic (carboxylate) groups, these compounds have amphiphilic character and therefore they can be considered as natural surfactants (Tombácz et al, 1988;Wandruszka, 2000). This character makes them able to form micelles; however, the critical micelle concentration (cmc) of humic acid was estimated to be as high as 10 g l -1 (Tschapek and Wasowski, 1984).…”

“…Since humic substances exhibit similar behaviour to surfactants (Tombácz et al, 1988;Wandruszka, 2000), the investigated compounds and HS can form mixed micelles resulting in alteration of the PSD curve and in the stability of the colloidal system. Therefore, we intended to make a detailed comparison between the adsorption isotherm generated on the soil and the PSD of the equilibrated soil extracts.…”

Humic acid–cetyltrimethylammonium bromide interaction: a fluorimetric study

“…Previous studies has been performed on surfactant-HA interactions, using alkylammonium-humate complexes by X-ray and interfacial tension measurements (31)(32)(33). Traina et al (34) studied the association of linear alkyl benzene sulphonates with humic substances, which increased with increasing chain length.…”