Investigation of herbicide sorption-desorption using pristine and organoclays to explore the potential carriers for controlled release formulation

Santosh Kumar Paul; Yunfei Xi; Peter Sanderson; Amal Kanti Deb; Md Rashidul Islam; Ravi Naidu

doi:10.1016/j.chemosphere.2023.139335

Investigation of herbicide sorption-desorption using pristine and organoclays to explore the potential carriers for controlled release formulation

Chemosphere. 2023 Oct:337:139335. doi: 10.1016/j.chemosphere.2023.139335. Epub 2023 Jun 30.

Authors

Santosh Kumar Paul¹, Yunfei Xi², Peter Sanderson³, Amal Kanti Deb⁴, Md Rashidul Islam³, Ravi Naidu⁵

Affiliations

¹ Global Centre for Environmental Remediation (GCER), ATC Building, The University of Newcastle, Callaghan, NSW 2308, Australia; CRC for Contamination Assessment and Remediation of the Environment (CRC CARE), ATC Building, The University of Newcastle, Callaghan, NSW 2308, Australia; Agronomy Division, Bangladesh Agricultural Research Institute (BARI), Joydebpur, Gazipur 1701, Bangladesh.
² Central Analytical Research Facility (CARF) & School of Chemistry and Physics - Faculty of Science, Queensland University of Technology, Brisbane, QLD 4001, Australia.
³ Global Centre for Environmental Remediation (GCER), ATC Building, The University of Newcastle, Callaghan, NSW 2308, Australia; CRC for Contamination Assessment and Remediation of the Environment (CRC CARE), ATC Building, The University of Newcastle, Callaghan, NSW 2308, Australia.
⁴ Global Centre for Environmental Remediation (GCER), ATC Building, The University of Newcastle, Callaghan, NSW 2308, Australia; CRC for Contamination Assessment and Remediation of the Environment (CRC CARE), ATC Building, The University of Newcastle, Callaghan, NSW 2308, Australia; Institute of Leather Engineering and Technology, University of Dhaka, Dhaka 1000, Bangladesh.
⁵ Global Centre for Environmental Remediation (GCER), ATC Building, The University of Newcastle, Callaghan, NSW 2308, Australia; CRC for Contamination Assessment and Remediation of the Environment (CRC CARE), ATC Building, The University of Newcastle, Callaghan, NSW 2308, Australia. Electronic address: Ravi.Naidu@newcastle.edu.au.

PMID: 37394186
DOI: 10.1016/j.chemosphere.2023.139335

Abstract

Injudicious application of available commercial herbicide formulations leads to water, air and soil contamination, which adversely affect the environment, ecosystems and living organisms. Controlled release formulation (CRFs) could be an effective way to reduce the problems associated with commercially available herbicides. Organo-montmorillonites are prominent carrier materials for synthesising CRFs of commercial herbicides. Quaternary amine and organosilane functionalised organo-montmorillonite and pristine montmorillonite were used to investigate their potential as suitable carriers for CRFs in herbicide delivery systems. The experiment involved a batch adsorption process with successive dilution method. Results revealed that pristine montmorillonite is not a suitable carrier for CRFs of 2,4-D due to its low adsorption capacity and hydrophilic nature. Conversely, octadecylamine (ODA) and ODA-aminopropyltriethoxysilane (APTES) functionalised montmorillonite has better adsorption capacities. Adsorption of 2,4-D onto both organoclays is higher at pH.3 (232.58% for MMT1 and 161.29% for MMT2) compared to higher pH until pH.7 (49.75% for MMT1 and 68.49% for MMT2). Integrated structural characterisation studies confirmed the presence of 2,4-D on the layered organoclays. The Freundlich adsorption isotherm model fitted best to the experimental data, which revealed an energetically heterogeneous surface of the experimental organoclays, and adsorption which specifically involved chemisorption. The cumulative desorption percentages of adsorbed 2,4-D from MMT1_{(2,4-D loaded)} and MMT2_{(2,4-D loaded)} after seven desorption cycles were 65.53% and 51.45%, respectively. This outcome indicates: firstly, both organoclays are potential carrier materials for CRFs of 2,4-D; secondly, they have the ability to reduce the instantaneous release of 2,4-D immediately after application; and thirdly, eco-toxicity is greatly diminished.

Keywords: 2,4-D; Controlled release formulation (CRFs); Herbicide; Montmorillonite; Organoclays.

MeSH terms

2,4-Dichlorophenoxyacetic Acid
Adsorption
Aluminum Silicates / chemistry
Bentonite / chemistry
Clay
Delayed-Action Preparations
Ecosystem
Herbicides* / chemistry

Substances

Herbicides
Bentonite
Aluminum Silicates
Delayed-Action Preparations
Clay
2,4-Dichlorophenoxyacetic Acid