Naslov
Interaction of Humic Substances and Aluminium Formation of Insoluble Associates

Autori
Petrović, Mira ; Kaštelan-Macan, Marija

Izvornik
Food technology and biotechnology (1330-9862) 34 (1996), 2-3; 81-85

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
Humic substances ; humic acids ; fulvic acids ; Al(III)ions interaction

Sažetak
The interaction of aluminum with soil humic (HA) and fulvic acids (FA) and formation of insoluble associates have been studied under laboratory conditions. The standard test procedure involved a series of experiments at one humic (and fulvic) concentration (50.0 mg/L and 68.5 mg/L, respectively) with varying concentrations of Al(III)-ions (0.5-5 mmol/L). The amounts of aluminum and humic substances precipitated where measured in the pH range from 2 to 10. It was found that, at any pH and regardless of mass ratio Al/HA, more than 85% of HA precipitate with aluminum. The formation of insoluble Al-fulvate is a pH-dependent reaction with precipitation maximum between pH=4-6. The principal mechanism in an acidic medium (pH<5) is complex formation through salicylate-type functional groups with binding capacity (at pH=4) 2 mmol Al/g HA and 3.8 mmol Al/g FA. At higher pH the reaction mechanism is primarily sorption of humic substances on "in situ" formed Al(OH)3.

Izvorni jezik
Engleski

Znanstvena područja
Kemijsko inženjerstvo

POVEZANOST RADA