Sorption of atrazine onto humic acids (HAs) coated nanoparticles

Abstract

a b s t r a c tWith the development of nanotechnologies, a large number of nano-materials with novel properties are being released into the environment. However, little is known about their fate, transport, toxicity and interactions with organic matters in aqueous environment. In this study, nano-SiO 2 or kaolinite, coated with soil humic acid (SHA) and peat humic acid (PHA), were used as sorbents. The original and HA-coated nanoparticles were characterized for particle size, TEM and electrophoretic mobility. Sequential ultrafiltration (UF) was used to characterize the molecular size fractionations of dissolved HAs. Sorption data of atrazine (AT) under various solution concentration, ionic strength and pH were well fitted with Freundlich model. Sorption amount of AT on HA-coated nanoparticles was significantly lower than that on original particles. The sorption maximum appeared at I = 0.001 mol/l (NaNO 3 ), pH 3. Size of nanoparticle aggregates, conformation of HA and specific surface area were factors affecting the sorption process. The compressed conformation of HA was more favorable for HA sorption than expanded one. Size of aggregation was not a determinant factor for the sorption process, while the specific surface areas of nano-sorbent was an important one. Results indicated that HA plays an important role in the transport and toxicity of nanoparticles and AT in aqueous environment.

Pb(II), Cr(VI) and atrazine sorption behavior on sludge-derived biochar: role of humic acids

“…The decrement became more substantial under a higher atrazine loading. In fact, the similar phenomenon was also reported by Lu et al (2009), who observed the amount of sorbed atrazine on humic acid-coated nanoparticles was significantly lower than that on the original ones. This can be partially ascribed to the increase in the hydrophility of the SDBC surface by humic acids.…”

Effect of Dispersion on Adsorption of Atrazine by Aqueous Suspensions of Fullerenes

“…Lu et al 29 reported that sorption of atrazine on HA-coated mineral nanoparticles was apparently lower than that on original particles. They found that the surface area of HA-coated nanoparticles was reduced due to the pore-blockage effect.…”

Tritium label in studying sorption of humic substances by carbon-based nanomaterials

“…All these fields are unified by one goal, which is the development of new materials with certain properties. To achieve this goal, a number of researchers investigate the interaction of HS with different colloids and nanoparticles [3][4][5][6]. In this aspect, carbon-based nanomaterianls should be taken into critical account.…”