Removal of glyphosate herbicide from water using biopolymer membranes

Enormous amounts of pesticides are manufactured and used worldwide, some of which reach soils and aquatic systems. Glyphosate is a non-selective herbicide that is effective against all types of weeds and has been used for many years. It can therefore be found as a contaminant in water, and procedure...

Full description

Saved in:

Bibliographic Details
Published in:	Journal of environmental management Vol. 151; pp. 353 - 360
Main Authors:	Carneiro, Rafael T.A., Taketa, Thiago B., Gomes Neto, Reginaldo J., Oliveira, Jhones L., Campos, Estefânia V.R., de Moraes, Mariana A., da Silva, Camila M.G., Beppu, Marisa M., Fraceto, Leonardo F.
Format:	Journal Article
Language:	English
Published:	England Elsevier Ltd 15-03-2015 Academic Press Ltd
Subjects:	Adsorption Affinity Alginate Alginates Biopolymers Chemical contaminants Chemicals Chitosan Chitosan - chemistry Environmental management Glucuronic Acid Glycine - analogs & derivatives Glycine - chemistry Glyphosate Herbicides Herbicides - chemistry Hexuronic Acids Isotherms Kinetics Membranes Nutrient removal Solubility Sorption Water - chemistry Water contamination Water Pollutants, Chemical - chemistry Water pollution Water Purification - methods Water supply Water utilization Sorption Membranes Alginate Chitosan Glyphosate Water contamination
Online Access:	Get full text
Tags:	Add Tag No Tags, Be the first to tag this record!

Description
Summary:	Enormous amounts of pesticides are manufactured and used worldwide, some of which reach soils and aquatic systems. Glyphosate is a non-selective herbicide that is effective against all types of weeds and has been used for many years. It can therefore be found as a contaminant in water, and procedures are required for its removal. This work investigates the use of biopolymeric membranes prepared with chitosan (CS), alginate (AG), and a chitosan/alginate combination (CS/AG) for the adsorption of glyphosate present in water samples. The adsorption of glyphosate by the different membranes was investigated using the pseudo-first order and pseudo-second order kinetic models, as well as the Langmuir and Freundlich isotherm models. The membranes were characterized regarding membrane solubility, swelling, mechanical, chemical and morphological properties. The results of kinetics experiments showed that adsorption equilibrium was reached within 4 h and that the CS membrane presented the best adsorption (10.88 mg of glyphosate/g of membrane), followed by the CS/AG bilayer (8.70 mg of glyphosate/g of membrane). The AG membrane did not show any adsorption capacity for this herbicide. The pseudo-second order model provided good fits to the glyphosate adsorption data on CS and CS/AG membranes, with high correlation coefficient values. Glyphosate adsorption by the membranes could be fitted by the Freundlich isotherm model. There was a high affinity between glyphosate and the CS membrane and moderate affinity in the case of the CS/AG membrane. Physico-chemical characterization of the membranes showed low values of solubility in water, indicating that the membranes are stable and not soluble in water. The SEM and AFM analysis showed evidence of the presence of glyphosate on CS membranes and on chitosan face on CS/AG membranes. The results showed that the glyphosate herbicide can be adsorbed by chitosan membranes and the proposed membrane-based methodology was successfully used to treat a water sample contaminated with glyphosate. Biopolymer membranes therefore potentially offer a versatile method to eliminate agricultural chemicals from water supplies. •Membranes of chitosan and alginate were used to adsorb glyphosate herbicide.•Glyphosate adsorption is dependent of the type of biopolymer membrane.•The Freundlich isotherm model could fit Glyphosate adsorption by the chitosan membrane.
Bibliography:	ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23
ISSN:	0301-4797 1095-8630
DOI:	10.1016/j.jenvman.2015.01.005