Physicochemical Study of the Sorption of Pesticides by Wood Components

Abstract

The sorption-desorption and interaction mechanisms of three non-ionic (linuron, alachlor, and metalaxyl) and two ionic (paraquat and dicamba) pesticides by three commercial lignins (hydrophobic macromolecule) and cellulose (hydrophilic macromolecule) as wood components were studied. Wood is a low-cost and environmentally friendly material proposed in recent years to immobilize pesticides in soils. The influence of sorbent and pesticide properties and the identification of the functional groups of the organic molecules involved in sorption were evaluated by a statistical approach and by Fourier transform infrared spectroscopy. The sorption isotherms of non-ionic pesticides by the lignins and cellulose fit the Freundlich model, and those of the ionic pesticides also fit the Langmuir model. The sorption constants of pesticides by cellulose were 62-, 9-, 24-, 119-, and 3-fold lower than those for the sorption by lignins. A predictive model of pesticide sorption indicated that 88.5% of the variability in the sorption coefficient normalized to the organic carbon content could be explained in terms of the variability of the polarity index and the octanol-water partition coefficient of sorbent and sorbate. The greater irreversibility observed for ionic pesticides was attributed to the involvement of simultaneous interaction mechanisms. The results obtained contribute the knowledge of sorption capacity of pesticides by lignin/cellulose, the main components of woods and ubiquitous materials in the environment.

Comparative fate of an organochlorine, chlordecone, and a related compound, chlordecone-5b-hydro, in soils and plants

“…Indeed, retention in root lipid materials (lignin, suberin) has been shown to play a key role in plant uptake of hydrophobic pollutants (Collins et al, 2006;Létondor et al, 2015). Likewise, the fiber content and the nature of the fibers, especially in the stem, are known to play a determining role in adsorption (Barak et al, 1983;Rodríguez-Cruz et al, 2009). A long fibrous stem (sugarcane vs. cabbage) could thus magnify the segregation due to the difference in adsorption on stem tissues, which would be consistent with the higher ratios we found in sugarcane stems than in cabbage stems.…”

Interaction of malathion, an organophosphorus pesticide with Rhizopus oryzae biomass

“…Thus intense research attention is now focused on cost effective, eco-friendly and easily available adsorbent particularly of biological origin. Different adsorbents such as agricultural byproducts, waste materials and microbial biomass have been utilized for removing different toxicants from wastewater [11][12][13][14][15][16][17][18][19].…”

Influence of novel lignocellulosic residues in a biobed biopurification system on the degradation of pesticides applied in repeatedly high doses

“…Lower degradation rates in biomixturescontaining PS could be attributed to the high lignin content of PS (Table 1), which may allow a greater adsorption of pesticides but decrease their bioavailability to be degraded by microorganisms. Rodríguez-Cruz et al (2009) reported that lignin has a greater adsorption capacity of both non-ionic and ionic pesticides than does cellulose, and a high correlation with the lignin content in the wood residues was found. Alternatively, the lower degradation in biomixtures with PS could be due to their high C/N ratio (51.8) (Table 2), causing a low availability of nutrients for the microorganisms, so that they establish themselves more slowly.…”